From: John Hernlund Subject: Re: [Fwd: [Fwd: Pymatuning, Ohio, Earthquake]] Date: Wed, 30 Sep 1998 14:28:29 -0700 (MST) Edward or Anyone Else, I take it there must not have been enough good data for a moment tensor solution? I have not seen one available, and I think it would be extremely interesting... ****************************************************************************** John Hernlund E-mail: hernlund@....... WWW: http://www.mc.maricopa.edu/academic/phy_sci/Geology/hernlund/ http://www.public.asu.edu/~hernlund/ "It is easier to excuse an ignorant person who claims that theory is unnecessary and dispensable in his supposed practice, than to excuse a Sophist who concedes its value to the schools (as, perhaps, only a mental exercise) but who at the same time maintains that matters are quite different in practice- that as one leaves school to enter the world, one will realize one has been pursuing empty ideals and philosophical dreams- and, in a word, that what sounds good in theory is of no practical use." -Immanuel Kant, On the Proverb: That May be True in Theory, But Is of No Practical Use ****************************************************************************** _____________________________________________________________________ Public Seismic Network Mailing List (PSN-L) From: Edward Cranswick Subject: Re: [Fwd: [Fwd: Pymatuning, Ohio, Earthquake]] Date: Wed, 30 Sep 1998 16:30:47 -0600 John- I've been so up to my ass in digital and bureaucratic alligators with our own aftershock program, I haven't had a chance to check. Let me know what you find. -Edward John Hernlund wrote: > Edward or Anyone Else, > I take it there must not have been enough good data for a moment tensor > solution? I have not seen one available, and I think it would be extremely > interesting... > > ****************************************************************************** > > John Hernlund > E-mail: hernlund@....... > WWW: http://www.mc.maricopa.edu/academic/phy_sci/Geology/hernlund/ > http://www.public.asu.edu/~hernlund/ > > "It is easier to excuse an ignorant person who claims that theory is > unnecessary and dispensable in his supposed practice, than to excuse a > Sophist who concedes its value to the schools (as, perhaps, only a mental > exercise) but who at the same time maintains that matters are quite > different in practice- that as one leaves school to enter the world, one > will realize one has been pursuing empty ideals and philosophical dreams- > and, in a word, that what sounds good in theory is of no practical > use." > -Immanuel Kant, On the Proverb: That May be True in Theory, But Is of No > Practical Use > > ****************************************************************************** > > _____________________________________________________________________ > > Public Seismic Network Mailing List (PSN-L) > > To leave this list email listserver@............. with the body of the > message: leave PSN-L -- Edward Cranswick US Geological Survey Golden, CO 80401 USA TEL: 303-273-8609 FAX: 303-273-8600 -------------------------------------------------------------- Pymatuning Earthquake Field Headquarters (1998 Sep 27 ... ) Cianci's Motel, 395 Mercer Rd (HWY#58), Greenville, PA 16125 TEL: 724-588-8550 _____________________________________________________________________ Public Seismic Network Mailing List (PSN-L) From: "Walt Williams" Subject: Those Pesky Little Geophones Date: Wed, 30 Sep 1998 19:49:22 +0000 Hello All, (they're back!) Could someone recommend book or paper which describe the geophone sensor? Thank you. Walt Williams, 98.09.30 dfheli@.............. _____________________________________________________________________ Public Seismic Network Mailing List (PSN-L) From: "Walt Williams" Subject: PSN-L: MagneTar Date: Wed, 30 Sep 1998 21:05:49 +0000 From: setv-l@........ To: seti-l@......... "'CS'" , "'FPS'" fpspace@.................>, "'ST'" Copies to: "'Don2'" , '''SK'" , "'ScottC'" Date sent: Wed, 30 Sep 1998 01:19:18 +0000 Subject: SETV-L:Tremendous GAMMA-Ray Flare Blasts Earth Send Copies to: Walt Williams Priority: normal Subject: SETI FW: TREMENDOUS GAMMA-RAY FLARE BLASTS EARTH Date sent: Tue, 29 Sep 1998 14:22:15 -0400 ---------- From: NASANews@........... Sent: Tuesday, September 29, 1998 2:10 PM To: undisclosed-recipients:; Subject: TREMENDOUS GAMMA-RAY FLARE BLASTS EARTH Donald Savage Headquarters, Washington, DC Sept. 29, 1998 (Phone: 202/358-1547) Tim Tyson Marshall Space Flight Center, Huntsville, AL (Phone: 256/544-0994) RELEASE: 98-172 TREMENDOUS GAMMA-RAY FLARE BLASTS EARTH An intense wave of gamma rays, emanating from a catastrophic magnetic flare on a mysterious star 20,000 light years away, struck the Earth's atmosphere on August 27, 1998, providing important clues about some of the most unusual stars in the Universe. Scientists said the gamma radiation posed no health risk to humans. The wave hit the night side of the Earth and ionized (or knocked electrons out of) the atoms in the upper atmosphere to a level usually seen only during daytime. This astonishing blast of ionization was detected by Prof. Umran Inan of Stanford University. "It is extremely rare for an event occurring outside the solar system to have any measurable effect on the Earth," Inan said. It was so powerful that it blasted sensitive detectors to maximum or off-scale on at least seven scientific spacecraft in Earth orbit and around the solar system. The wave of radiation emanated from a newly discovered type of star called a magnetar. Magnetars are dense balls of super- heavy matter, no larger than a city but weighing more than the Sun. They have the greatest magnetic field known in the Universe, so intense that it powers a steady glow of X-rays from the star's surface, often punctuated by brief, intense gamma-ray flashes, and occasionally by cataclysmic flares like the one observed on August 27. Astronomers think that all these effects are caused by an out-of-control magnetic field -- a field capable of heating, mixing, and sometimes cracking the star's rigid surface to bits. In June a team of scientists led by Dr. Chryssa Kouveliotou of NASA's Marshall Space Flight Center in Huntsville, AL, used NASA's Compton Gamma Ray Observatory to detect a series of about 50 flashes from the star, a type called a Soft Gamma Repeater (SGR), known as "SGR1900+14" in the constellation Aquila. During the flashing episode, Kouveliotou's team, in collaboration with Dr. Tod Strohmayer and his colleagues at NASA's Goddard Space Flight Center, Greenbelt, MD, pointed sensitive X-ray detectors aboard NASA's Rossi X-ray Timing Explorer satellite toward the star. They found faint X-rays coming from the star, which pulsed regularly in intensity every 5.16 seconds. These 5.16-second pulses already had been detected in April, when Dr. Kevin Hurley, University of California, Berkeley, aimed the Japanese/NASA Advanced Satellite for Cosmology and Astrophysics (ASCA) at the star. Comparisons of the ASCA and RXTE data showed that the X-ray pulses were gradually slowing down. The finding implies that the Soft Gamma Repeater has a magnetic field about 800 trillion times stronger than Earth's magnetic field, and about 100 times stronger than any found anywhere in the Universe. Kouveliotou and her team had earlier found that another SGR was also a magnetar. This was exactly what Dr. Robert Duncan, University of Texas, Austin, and Dr. Christopher Thompson, University of North Carolina, Chapel Hill, predicted in 1992 when they originated the "magnetar" theory. Before the NASA team could announce these conclusions, SGR1900+14 emitted the tremendous flare of August 27, which was observed by almost every spacecraft with a high-energy radiation detector in space. "Magnetars seem to answer several mysteries about the structure and evolution of stars," said Kouveliotou. "We think magnetars spend their first 10,000 years as Soft Gamma Repeaters. As they weaken with age and slow their rotation, they become Anomalous X-ray Pulsars -- stars that do not have enough 'juice' to flash anymore, but which emit a steady flow of X-rays for perhaps another 30,000 years. After that, they fade to black and drift for eternity through the heavens. The absence of observable pulsars in some supernova remnants just means that the pulsar's lights have gone out sooner than we expected." A magnetar forms from the explosion, or supernova, of a very large, ordinary star. The star's heavy center collapses under its own gravity into a dense ball of super-compressed matter 12 miles across. This "neutron star" consists mostly of neutrons in a dense fluid, but the outer layers solidify into a rigid crust of atoms about 1 mile deep, with a surface of iron. Even with this solid crust, a magnetar is incredibly unstable. Almost unimaginable magnetic fields, about 800 trillion times that of Earth's, cause the crust to crack and ripple in powerful starquakes. The energy released in these explosive starquakes streams out into space as intense flashes of gamma- rays. In the August 27 flare, pure magnetic energy was also released, as the star's entire crust was broken to bits. "A magnet this strong could erase the magnetic strip on the credit cards in your wallet or pull the keys out of your pocket from a distance halfway to the Moon," said Duncan. - end - EDITOR'S NOTE: Additional information on magnetars or the Aug. 27 event is available on the internet at: http://www1.msfc.nasa.gov/NEWSROOM/ and http://www.magnetars.com/ * * * NASA press releases and other information are available automatically by sending an Internet electronic mail message to domo@............ In the body of the message (not the subject line) users should type the words "subscribe press-release" (no quotes). The system will reply with a confirmation via E-mail of each subscription. A second automatic message will include additional information on the service. NASA releases also are available via CompuServe using the command GO NASA. To unsubscribe from this mailing list, address an E-mail message to domo@............ leave the subject blank, and type only "unsubscribe press-release" (no quotes) in the body of the message. _____________________________________________________________________ Public Seismic Network Mailing List (PSN-L) From: Greg Subject: Re: Those Pesky Little Geophones Date: Wed, 30 Sep 1998 22:03:33 -0700 Walt Williams wrote: > Could someone recommend book or paper which describe the > geophone sensor? I still have my sorry little FAQ up at: http://www.treefort.org/~ghost/geo.html You probably wanted something a bit more detailed... let me know what it is when you find it. ;) ,Greg _____________________________________________________________________ Public Seismic Network Mailing List (PSN-L) From: GeE777@....... Subject: Re: Those Pesky Little Geophones Date: Thu, 1 Oct 1998 11:29:29 EDT Hello, Try "ENCYCLOPEDIC DICTIONARY OF EXPLORATION GEIOPHYSICS" by R. E. Sheriff published by the Society of Exploration Geophysics, Tulsa OK, U. S. A. In a message dated 98-09-30 22:54:30 EDT, dfheli@.............. writes: << Could someone recommend book or paper which describe the geophone sensor? >> _____________________________________________________________________ Public Seismic Network Mailing List (PSN-L) From: lahr@.................. Subject: Mechanism of the Pymatuning, Ohio, Earthquake Date: Thu, 1 Oct 1998 09:30:46 -0600 (MDT) The Harvard mechanism indicates predominantly thrust due to northeast-southwest compression. JCLahr > From sipkin@gldage Thu Oct 1 09:25 MDT 1998 > Date: Thu, 1 Oct 1998 09:25:25 -0600 > From: sipkin@gldage (Stuart Sipkin) > To: lahr@.................. > Subject: Re: Ohio/Penn. EQ > > John, > > The following is from Harvard. > > Stuart > > ------------------------------------------------------------------------------- > > Here is a preliminary CMT solution for the recent OHIO earthquake. The solution > is calculated from intermediate period surface waves recorded on the USGS > National Seismic Network. > > September 25, OHIO, Mw=4.5 > > Goran Ekstrom > > CENTROID, MOMENT TENSOR SOLUTION > HARVARD EVENT-FILE NAME B092598X > DATA USED: NSN > L.P. BODY WAVES: 17S, 25C, T= 32 > CENTROID LOCATION: > ORIGIN TIME 19:52:55.3 0.2 > LAT 41.43N 0.04;LON 80.41W 0.03 > DEP 12.0 FIX;HALF-DURATION 1.0 > MOMENT TENSOR; SCALE 10**22 D-CM > MRR= 4.83 0.67; MTT= 0.95 0.71 > MFF=-5.77 0.31; MRT=-0.20 0.99 > MRF=-0.39 0.92; MTF= 5.92 0.38 > PRINCIPAL AXES: > 1.(T) VAL= 5.04;PLG=60;AZM=148 > 2.(N) 4.18; 30; 330 > 3.(P) -9.23; 1; 240 > BEST DOUBLE COUPLE:M0=7.1*10**22 > NP1:STRIKE=303;DIP=51;SLIP= 51 > NP2: 176; 53; 128 > > ###-------- > ######------------- > #######---------------- > ###-----#------------------ > --------########------------- > ---------###########----------- > --------##############--------- > ---------################-------- > ---------##################------ > ---------###################----- > ---------######### ########---- > ---------######## T #########-- > ------######## #########-- > P -------###################- > --------################## > --------############### > -------############ > -----###### > _____________________________________________________________________ Public Seismic Network Mailing List (PSN-L) From: Edward Cranswick Subject: Re: Mechanism of the Pymatuning, Ohio, Earthquake Date: Thu, 01 Oct 1998 12:17:57 -0600 John- I heard from someone that there was a large non-double-couple component to the mechanism (which could be the apparent result caused by near-surface, high-frequency wave-propagation complexities) which suggested that the event may have been caused by a collapse rather than by slip on a fault plane, and, hence, aftershocks are not to be expected. However, I believe that large collapses are dangerous and also need to be investigated. -Edward lahr@.................. wrote: > The Harvard mechanism indicates predominantly thrust due > to northeast-southwest compression. > > JCLahr > > > From sipkin@gldage Thu Oct 1 09:25 MDT 1998 > > Date: Thu, 1 Oct 1998 09:25:25 -0600 > > From: sipkin@gldage (Stuart Sipkin) > > To: lahr@.................. > > Subject: Re: Ohio/Penn. EQ > > > > John, > > > > The following is from Harvard. > > > > Stuart > > > > ------------------------------------------------------------------------------- > > > > Here is a preliminary CMT solution for the recent OHIO earthquake. The solution > > is calculated from intermediate period surface waves recorded on the USGS > > National Seismic Network. > > > > September 25, OHIO, Mw=4.5 > > > > Goran Ekstrom > > > > CENTROID, MOMENT TENSOR SOLUTION > > HARVARD EVENT-FILE NAME B092598X > > DATA USED: NSN > > L.P. BODY WAVES: 17S, 25C, T= 32 > > CENTROID LOCATION: > > ORIGIN TIME 19:52:55.3 0.2 > > LAT 41.43N 0.04;LON 80.41W 0.03 > > DEP 12.0 FIX;HALF-DURATION 1.0 > > MOMENT TENSOR; SCALE 10**22 D-CM > > MRR= 4.83 0.67; MTT= 0.95 0.71 > > MFF=-5.77 0.31; MRT=-0.20 0.99 > > MRF=-0.39 0.92; MTF= 5.92 0.38 > > PRINCIPAL AXES: > > 1.(T) VAL= 5.04;PLG=60;AZM=148 > > 2.(N) 4.18; 30; 330 > > 3.(P) -9.23; 1; 240 > > BEST DOUBLE COUPLE:M0=7.1*10**22 > > NP1:STRIKE=303;DIP=51;SLIP= 51 > > NP2: 176; 53; 128 > > > > ###-------- > > ######------------- > > #######---------------- > > ###-----#------------------ > > --------########------------- > > ---------###########----------- > > --------##############--------- > > ---------################-------- > > ---------##################------ > > ---------###################----- > > ---------######### ########---- > > ---------######## T #########-- > > ------######## #########-- > > P -------###################- > > --------################## > > --------############### > > -------############ > > -----###### > > > > _____________________________________________________________________ > > Public Seismic Network Mailing List (PSN-L) > > To leave this list email listserver@............. with the body of the > message: leave PSN-L -- Edward Cranswick US Geological Survey Golden, CO 80401 USA TEL: 303-273-8609 FAX: 303-273-8600 -------------------------------------------------------------- Pymatuning Earthquake Field Headquarters (1998 Sep 27 ... ) Cianci's Motel, 395 Mercer Rd (HWY#58), Greenville, PA 16125 TEL: 724-588-8550 _____________________________________________________________________ Public Seismic Network Mailing List (PSN-L) From: John Hernlund Subject: Re: Mechanism of the Pymatuning, Ohio, Earthquake Date: Thu, 01 Oct 1998 11:57:46 -0700 (MST) On Thu, 1 Oct 1998, Edward Cranswick wrote: > I heard from someone that there was a large non-double-couple component > to the mechanism (which could be the apparent result caused by near-surface, > high-frequency wave-propagation complexities) which suggested that the event > may have been caused by a collapse rather than by slip on a fault plane, > and, hence, aftershocks are not to be expected. However, I believe that > large collapses are dangerous and also need to be investigated. > -Edward That is very interesting indeed. The depth is given as 12.0 below, which would have to mean something collapse-able survived to that depth, provided that the depth is accurate. Are there any inferences from cross-sections, etc. that might guess what kind of structure is down there? I would guess mostly metamorphics, possibly metasedimentary rocks? I wonder how many old faults from the Appalachian episode might exist on the West side of the mountains... > > The Harvard mechanism indicates predominantly thrust due > > to northeast-southwest compression. > > > DEP 12.0 FIX;HALF-DURATION 1.0 > > > MOMENT TENSOR; SCALE 10**22 D-CM > > > BEST DOUBLE COUPLE:M0=7.1*10**22 > > > NP1:STRIKE=303;DIP=51;SLIP= 51 > > > NP2: 176; 53; 128 > > > ###-------- > > > ######------------- > > > #######---------------- > > > ###-----#------------------ > > > --------########------------- > > > ---------###########----------- > > > --------##############--------- > > > ---------################-------- > > > ---------##################------ > > > ---------###################----- > > > ---------######### ########---- > > > ---------######## T #########-- > > > ------######## #########-- > > > P -------###################- > > > --------################## > > > --------############### > > > -------############ > > > -----###### ****************************************************************************** John Hernlund E-mail: hernlund@....... WWW: http://www.mc.maricopa.edu/academic/phy_sci/Geology/hernlund/ http://www.public.asu.edu/~hernlund/ "It is easier to excuse an ignorant person who claims that theory is unnecessary and dispensable in his supposed practice, than to excuse a Sophist who concedes its value to the schools (as, perhaps, only a mental exercise) but who at the same time maintains that matters are quite different in practice- that as one leaves school to enter the world, one will realize one has been pursuing empty ideals and philosophical dreams- and, in a word, that what sounds good in theory is of no practical use." -Immanuel Kant, On the Proverb: That May be True in Theory, But Is of No Practical Use ****************************************************************************** _____________________________________________________________________ Public Seismic Network Mailing List (PSN-L) From: BZIMMERMAN@............ Subject: Re: Mechanism of the Pymatuning, Ohio, Earthquake Date: Thu, 01 Oct 1998 15:10:29 -0500 (EST) If you move closer to the surface the Salina Group salt beds come into play. Depth 3,000-5,000 feet here in Erie County and geetting deeper as you go south. How precise is the depth determination ? Brian Zimmerman _____________________________________________________________________ Public Seismic Network Mailing List (PSN-L) From: John Hernlund Subject: Re: Mechanism of the Pymatuning, Ohio, Earthquake Date: Thu, 01 Oct 1998 12:41:02 -0700 (MST) On Thu, 1 Oct 1998 BZIMMERMAN@............ wrote: > If you move closer to the surface the Salina Group salt beds come into > play. Depth 3,000-5,000 feet here in Erie County and geetting deeper as > you go south. > How precise is the depth determination ? Since local coverage is very poor, and the body waves complicated further as mentioned before I am sure it probably isn't very good. I like the idea of salt beds though... ****************************************************************************** John Hernlund E-mail: hernlund@....... WWW: http://www.mc.maricopa.edu/academic/phy_sci/Geology/hernlund/ http://www.public.asu.edu/~hernlund/ "It is easier to excuse an ignorant person who claims that theory is unnecessary and dispensable in his supposed practice, than to excuse a Sophist who concedes its value to the schools (as, perhaps, only a mental exercise) but who at the same time maintains that matters are quite different in practice- that as one leaves school to enter the world, one will realize one has been pursuing empty ideals and philosophical dreams- and, in a word, that what sounds good in theory is of no practical use." -Immanuel Kant, On the Proverb: That May be True in Theory, But Is of No Practical Use ****************************************************************************** _____________________________________________________________________ Public Seismic Network Mailing List (PSN-L) From: meredith lamb Subject: Hall scanned circuit/s is on web site Date: Thu, 01 Oct 1998 14:07:15 -0600 Hi guys, Now have rough scanned circuits of Robert Lamb's Hall amplifier on my web site. The main amplifier needs to be redrawn, but the gist of it is there. Redrew the simplified meter circuit. Thats all the electronics involved. No power supply circuit drawn and its presumed to be other equipment. The 10K resistor coming off terminal 9 feeds directly into Larry Cochranes board & SDR program; other programs/boards may have to be adjusted however. http://www.geocities.com/ResearchTriangle/Facility/1739/index.html The web site needs a gob more detail with the circuit description and operation, parts list, etc. Eventually it will come. Thanks, Meredith Lamb _____________________________________________________________________ Public Seismic Network Mailing List (PSN-L) From: S-T Morrissey Subject: vbb zero drift Date: Thu, 1 Oct 1998 18:59:18 -0500 (CDT) Barry, Regarding your questions about the need for frequent recentering of your VBB instrument and how this is done with commercial units: The key parameter that effects the thermal stability is the operating period. A 100 second sensor will be about 10 times more of a problem than a 10 second sensor, everything else being equal. So every effort is made in the design to reduce mechanical thermal effects as much as possible. This is one of the reasons that the commercial units are so expensive. But even when the commercial units specify an operating range of +,- 10 degC without re-zeroing, it actually means that the mass or boom will move through its full range during that temperature change. For these sensors, the mass position voltage may range +- 10 volts, but the diurnal earth tides may be 1% of this, equilavent to a temperature change of only 0.1 degC, which, of course, must be much less than this if one wants to record the tides without thermal noise. This is why very careful site selection and elaborate site prepartions are necessary, and sites in deep vaults or caverns are preferable. Link from the PSN site page re. "information, equipment, and software" to the "Guidelines for Installing Broadband Seismic Stations" by the Berkeley Seismo. Lab for a detailed discussion. In general the insulation, etc, should be sufficient so that no daily thermal effects are seen, but seasonal temperature changes might require recentering. The commercial sensors have automatic re-centering features that either drive a miniature motor or apply a DC correction to the displacement detector output. They also have a relatively long time recommended for them to reach thermal stability, like several days. The commercial sensors generally are digitized with 24-bit resolution, or 1 part per 16 million, so the output is always on-scale. The DC offset caused by temperature is removed in processing. But for 16-bit digitizers, a high-pass filter is necessary to keep the data within the range of the digitizer. If the filter period is at least 10 times the longest period of the data, it will not affect the response. So for the 100-second STM-8, I use a 2000-second (2x 4000 ufarad in series, with 1 megohm, a single-pole) high pass coupling into the output amplifier. My RS multimeter digitizer is +,- 200 mv full scale, with the LSB being 0.1 millivolt; the daily temperature drift of the VBB output ranges from 0.1 to 1 volt, but the filter keeps this from the digitizer. I haven't had to re-center the sensor operating in the basement for several weeks, although its output has wandered around by several volts. Regards, Sean-Thomas _____________________________________________________________________ Public Seismic Network Mailing List (PSN-L) From: Edward Cranswick Subject: Re: Mechanism of the Pymatuning, Ohio, Earthquake Date: Thu, 01 Oct 1998 20:11:24 -0600 Brian- Someone will quantify the depth uncertainty, I hope. Thank you for your remarks in your previous post; it was good to meet you. I think that, with your expertise in economic geology and your interest and knowledge of seismology in conjunction with your proximity, you are in a position to make a valuable contribution to the study of the Pymatuning Earthquake. -Edward BZIMMERMAN@............ wrote: > If you move closer to the surface the Salina Group salt beds come into > play. Depth 3,000-5,000 feet here in Erie County and geetting deeper as > you go south. > > How precise is the depth determination ? > > Brian Zimmerman > > _____________________________________________________________________ > > Public Seismic Network Mailing List (PSN-L) > > To leave this list email listserver@............. with the body of the > message: leave PSN-L -- Edward Cranswick US Geological Survey Golden, CO 80401 USA TEL: 303-273-8609 FAX: 303-273-8600 -------------------------------------------------------------- Pymatuning Earthquake Field Headquarters (1998 Sep 27 ... ) Cianci's Motel, 395 Mercer Rd (HWY#58), Greenville, PA 16125 TEL: 724-588-8550 _____________________________________________________________________ Public Seismic Network Mailing List (PSN-L) From: Greg Subject: Re: Dataq acquisition module Date: Fri, 02 Oct 1998 04:53:20 +0000 Gregory Bajuk wrote: > Dataq Instruments has an Internet special price promotion on a serial port > data acquisition module DI-150. Features 2 channels, +/- 10 volt input, The internet special is for the DI-150-SP. They also sell the DI-150-RS. The SP model is not stable in the +-100mv range. Luckily I got a sales guy that knew what was going on. Hopefully nobody bought something that they didn't want. ,Greg _____________________________________________________________________ Public Seismic Network Mailing List (PSN-L) From: "Steve Carniglia" Subject: Re: Dataq acquisition module Date: Fri, 2 Oct 1998 08:14:10 -0700 I sent the board to Ted Blank.....he tried to make his software work = with the DI190...He felt that the problem was in the video graphics area = so his software would not work. Other than that, Ted was able to see = the board. I do not know about the other software out there...please = let me know if you know of software that is compatible.... Thanks Steve =20 -----Original Message----- From: Francesco To: PSN-L Mailing List Date: Wednesday, September 30, 1998 11:22 AM Subject: R: Dataq acquisition module =20 =20 Which problem have the board using our software (Sdr or Emon or Wq?) = ? =20 Regards Francesco Nucera
I sent the board to Ted Blank.....he = tried to=20 make his software work with the DI190...He felt that the problem was in = the=20 video graphics area so his software would not work.  Other than = that, Ted=20 was able to see the board.  I do not know about the other software = out=20 there...please let me know if you know of software that is=20 compatible....
 
Thanks
Steve
 
-----Original = Message-----
From:=20 Francesco <franuc@......>
To: = PSN-L=20 Mailing List <psn-l@.............>
Dat= e:=20 Wednesday, September 30, 1998 11:22 AM
Subject: R: = Dataq=20 acquisition module

Which problem have the board = using our=20 software (Sdr or Emon or Wq?) ?
 
Regards
Francesco=20 Nucera
From: GeE777@....... Subject: Re: Those Pesky Little Geophones Date: Fri, 2 Oct 1998 12:24:26 EDT Hi, This is taken grom "Seismic Exploration Fundamentals" by J. A. Coffeen p66,67 <<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<< Geophone A geophone is a device for detecting sounds from the earth--geo, earth; phone, sound. The type of geophone generally used in seismic exploration on land consists of a strong permanent magnet and a coil of wire, around the magnet, all in a rugged case. The magnet is attached rigidly to the case, which can also retain the magnetic field. The coil, made of fine copper wire wound many times around, is connected to the case by a spring. The geophone is placed in firm contact with the ground. Then any shaking of the ground will shake the case and magnet. The coil, suspended on its spring, will not move as quickly. So the magnet moves up and down past the coil. Relative movement between magnet and coil generates electric current, on this small scale, just as it does in the dynamoes that power cities. The ends of the coil are connected to a "pigtail", a pair of wires extending from the case. to be connected, through the cable, to the recording equipment. The bits of current generated by the movements of the magnet make up the signal from the geophone. They are in proportion to the speed the magnet moves past the coil, so this type of detector is called a velocity geophone. Geophones are set out by recording helpers, "jug hustlers". The "string" of geophones for a group is put on the ground at a set distance from each other. Good contact with the ground is assured. Geophones often have spikes on the bottom, so they can be stabbed into the ground. For frozen ground, they may be flat-bottomed, and need to be pressed into place, or grass scraped aside. Assuring the good contact is "planting" the geophones. A good plant is one in which the contact will allow vibration to be transmitted well from the earth to the geophone. >>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>> I am retired from a major oil company research department. I have 8 patents concerning geophones. My expermints indicate that if a geophone can easilly be buried 10 to 20 cm below the surface, there is a much better coupling than on the surface. It is best to remove the "spike" before burying the geophone. This gives the geophone a better impedance match with the earth. You must remember, that most of the time we in the exploration industry are looking for higher frequencies than in the natural seismic studies. George Erich _____________________________________________________________________ Public Seismic Network Mailing List (PSN-L) From: S-T Morrissey Subject: new, revised schematics for VRDT Date: Fri, 2 Oct 1998 20:36:57 -0500 (CDT) Re: VBB schematics: I have just scanned some new and revised schematic drawings regarding the VRDT displacement detector for the VBB seismometer. The drawings are found on the "figures, schematics, drawings ..." page at: http://www.eas.slu.edu/People/STMorrissey/index.html Fig 5 is a hopefully final update of the precision sine wave oscillator that is used (at 5 khz output) with the VRDT. Fig 6 is a NEW drawing showing the connections of the VRDT in the bridge circuit between the oscillator and the amplifier/demodulator. Fig 7 is a final update of the bridge amplifier/demodulator/ DC amplifier, with specific attention to use with a VRDT. Fig 13 shows the results of a sine wave calibration of the 90-second VBB sensor compared with the response indicated by the transfer function. Fig 14 is a plot of the digital data for the sine calibration. A "constant velocity" method was used, which is explained. Regards, Sean-Thomas _____________________________________________________________________ Public Seismic Network Mailing List (PSN-L) From: "Rex Klopfenstein, Jr." Subject: VBB Schematics Date: Sat, 03 Oct 1998 11:47:06 -0400 Thanks a lot for the updated schematics, this really pulls the VBB electronics together! I would also like your opinion on breadboarding techniques. I have been using vector board (perf board with holes on .01" centers), IC sockets, and vector clips (small clips that are pushed into .01" holes of perf board & components are soldered on one side, wiring on other). I have been looking into a new system that works with surface-mount components, but it is rather expensive. Everything is soldered on small boards that are then attached to a large board that acts as a ground plane I realize that the above technique has to be done with some thought for high frequency applications; such as, 'large' power feeds (star connections) and try to avoid 'long' parallel runs. What about low noise techniques? I realize that an etched pc board is the best, but for one-shot applications it isn't economically feasible. Rex Klopfenstein, Jr Bowling Green, OH _____________________________________________________________________ Public Seismic Network Mailing List (PSN-L) From: barry lotz Subject: Re: vbb zero drift Date: Sat, 03 Oct 1998 10:21:26 -0700 Sean Thomas Thanks for the info on the commercial units. It would be nice to be able to set a unit down in the field in a reasonably level site and walk away. I am still hopefull. Regards Barry PS I picked up a small FB accelerometer from a gentleman with a company called CFX out of Pennsylvania. I have it hooked up adjacent to my VBB and Lehman. The output calibration shows a flat output from DC to 25 hz. It didn't pick up a 4.7 event in S. Cal @ 677k (did with Lehman) but I am hopeful on a teleseismic event. It did pick up a local Redding 3.1 event. It's about 1" in diameter and about 1.5" tall. It wasn't cheap ($170). It requires 6-12 vts @ about 8 ma. Regards Barry _____________________________________________________________________ Public Seismic Network Mailing List (PSN-L) From: S-T Morrissey Subject: prototype PC boards Date: Sat, 3 Oct 1998 13:52:30 -0500 (CDT) Rex, RE. prototyping circuit boards, aka one-of-a-kind specials: For quick evaluation of circuits I have been using the solderless breadboards (the square white push-in boards, as in Newark pg 1579, similarly available at Radio Shack) for many years. They can have flaky connections, especially if oversize wires/leads are forced into the holes, or if they have been exposed to dampness. THey can handle a few to a dozen ICs. But for a permanent prototype, or a few special circuits with ICs, I use the Vector boards that have some pre-printed foil patterns on one side, such as their 3677-6 (Newark pg 547, $21 for a 4.5 x 8" board). I cut them to size with an office paper cutter. There are many patterns available, but this seems to be the most generic, and the continuous busses can be used for DC supplies or ground. I have tried their spring-clip mounting, but they are unreliable the long run. I prefer to have things soldered in, and to use good quality IC sockets. I use "solder wick" to remove or change components, or a header in an IC socket for an experimental set of Rs and Cs for such things as a filter. For some digital interfaces, I have used the same boards with IC sockets with wire-wrap pins, and headers for components, and they have worked for years. But I think that a fully soldered epoxy-base board with quality IC sockets is just as good as an etched PC board wrt noise, etc., and we certainly are not pushing any high frequency considerations. I have little experience with the surface mount prototyping, since It seems to lock one into a rather inflexible style and component choice. My old eyes prefer more visible components anyhow. Regards, Sean-Thomas _____________________________________________________________________ Public Seismic Network Mailing List (PSN-L) From: frankcnd@.................... (Frank Condon) Subject: Salton Sink Hot-Spot Date: Sat, 3 Oct 1998 12:12:31 -0700 (PDT) Hello: I need you all to evaluate this GOES satellite information as relayed to me through the University of Hawaii Hot-Spot Web Page. Apparently, "Bombay Beach" is showing something that indicates to them possible volcanic activity under the Salton Sea. Note: the use of the word "Anaheim." Why isn't it titled as to the proper location under the Salton Sea? http://volcano1.pgd.hawaii.edu/goes/anaheim/latest.shtml What is this all about? Frank Condon "Located in the seismic corridor somewhere between Fontana and Mammoth Lakes" _____________________________________________________________________ Public Seismic Network Mailing List (PSN-L) From: "Charles R. Patton" Subject: Re: Breadboard techniques Date: Sat, 03 Oct 1998 12:40:13 -0700 Rex, you asked: =93I would also like your opinion on breadboarding techniques.=94 I would answer as follows: 1) Unless you have a space problem, I personally like the 0.1=94 hole center perf board because there are still huge quantities of parts with pinouts that fit this layout, from connectors to IC=92s. 2) When doing low frequency, perhaps 1 MHz or below, I use wire wrap, and above that frequency I start using point-to-point wire soldered on the pads. 3) And MOST IMPORTANT (and I cannot overemphasize this point) =96 Never use the plain perf board with just holes or holes with solder pads only. Get perf board with a ground plane on one side. This advice applies from DC to light! The ground plane is your best protection from all sorts of =93squirrely=94 behavior with problems ranging from hum to intermittent performance. At work I had special 9=94x9=94 breadboards la= id out and we buy them in quanity. I have only found two sources of something satisfactory in the marketplace. A few are Vector and generally are PC form factor plug-in breadboards with ground planes. These are in the $50 plus price range. The best deal I have found is from: Marlin P. Jones & Assoc. Inc. Phone: 561-848-8236 FAX: 561-844-8764 P.O.Box 12685 Lake Park, Florida 33403-0685 In their 98-4AB catalog on page 86 they have two 6.5=94 x 4.125=94 Proto cards, 0.062=94 Epoxy glass boards with ground plane one side and pads on the other side. I bought one of the 9033-PB boards and found it to be just fine. They are solder plated and routed to shape. Order no.: 9033-PB donut pads $8.95 9035-PB square pads $8.95 They have a $15.00 minimum order policy, but two of these boards will fill that. You can use most SMT parts on the 0.1=94 center pads since most IC=92s us= e 0.05=94 lead spacing. So you solder alternate leads to the adjacent pad row and the remaining leads to the next row over. I.e.: |______| -- IC U U U U -- leads O | O | O --0.1=94 center pads / / -- wire jumpers O O O --0.1=94 center pads Anyway, just a few comments on breadboarding. Hope they help. Charles R. Patton, Editor, Geo-Monitor _____________________________________________________________________ Public Seismic Network Mailing List (PSN-L) From: "Daryl P. Dacko" Subject: Re: Breadboard techniques Date: Sun, 04 Oct 1998 09:06:16 -0400 At 12:40 PM 10/3/98 -0700, you wrote: >3) And MOST IMPORTANT (and I cannot overemphasize this point) =96 Never >use the plain perf board with just holes or holes with solder pads >only. Get perf board with a ground plane on one side. This advice >applies from DC to light! The ground plane is your best protection from >all sorts of =93squirrely=94 behavior with problems ranging from hum to >intermittent performance.=20 I can get away without a ground plane, but I'm fairly good at laying out and adding enough bypass caps to stop such behavior... A very cheap, very good, but very ugly method of breadboarding is 'dead bug' style: Use unetched pc board with continious copper plateing and lay the IC's=20 on their back with the pin's (legs) straight up in the air. Use a=20 drop of instant glue to hold them in place. Solder componests directly to the pc board when you need a ground, and support the supply rails and long signal runs on bypass caps or high=20 ohmage resistors. Interconenct the components with their own leads or waste pieces of cut off leads. Probabaly the uglyest way to breadboard ever seen, but it has better=20 high frequency performance than any breadboarding system I've ever seen. I usually use two inch square pieces of board, with only one or two IC's on each 'module' and just interconnect as needed. This lets you try a=20 new low-noise front end, for example, while leaving the rest of your=20 lashup alone... Just another opinion/option/method ;') Daryl _____________________________________________________________________ Public Seismic Network Mailing List (PSN-L) From: ACole65464@....... Subject: Re: Breadboard techniques Date: Sun, 4 Oct 1998 11:29:13 EDT Daryl, Thanks for sharing the "dead bug" idea for breadboarding electronic circuits. It sounds simple. Ideas for circuit fabrication covers an area of design that many of us need to hear about. Allan Coleman _____________________________________________________________________ Public Seismic Network Mailing List (PSN-L) From: CARRJJ@....... Subject: Re: Breadboard techniques Date: Sun, 4 Oct 1998 13:09:40 EDT The problem with ground plane perf boards is component thru-lead shorts. Some catalogs where these things are sold also sell a little tool for scraping away the copper around a hole just a little bit. It helps a lot. Ditto on the comments about solving problems. Joe Carr _____________________________________________________________________ Public Seismic Network Mailing List (PSN-L) From: S-T Morrissey Subject: circuit boards Date: Sun, 4 Oct 1998 13:45:02 -0500 (CDT) Re: perforated boards with ground planes: Quite obviously the ground plane helps the noise figure, but my experience with it tends to be more related to hidden shorts of component leads, etc.. I have not found it to be necessary for sub-audio (ie seismic) amplifiers, especially when proper power supply by-passing, etc, is used. And when a perf-board proto is turned into a printed/etched board, any double-sided layout ups the complication ante, both for printing/etching proofs of the artwork in our darkroom, or getting them printed/drilled commercially. The component side layout is simulated and tested by copying the layout in reverse through the translucent mylar sheet. Also, for noise protection, we have to assume that the circuit has some external metal shielding/enclosure, and that the noise is contained by proper filtering/bypassing of the signal/power leads at the connector. I have used a variation of the "dead bug" construction technique for lightning suppression modules. Lightning loves a circuit board, and will flash over the entire surface unless it it very clean and dry and properly coated, vaporizing the foil conductors as it goes. SO for the DC power and analogue data lightning protection modules, we use a single high-barrier terminal strip with insulated "turret" style connections, further insulated with shrink tube as they pass through the holes drilled in the box, and mount the larger components (Varistors, inductors, etc) adjacent to the strip (ie on the inside of the cover of the aluminum box) with large gobs of RTV sealant. Smaller components mount directly to the terminal strip. For the UHF/VHF antenna coupler, all the components "hang" between the UHF/N/or BNC connectors at each end. The lightning cannot "bypass" the devices by flashing over an epoxy PC board. By the way, the PC artwork of the circuits of the VRDT oscillator and demodulator are available, both as the 2x original, which I can reduce to 1x on a transparency with the copier. I also have the reversed 1x printing films that can be copied to a transparency, but the result is not dark or dense enough to print a photo-resist. There is some progress in consolidating all the VBB electronics into one or two PC cards that would be available commercially. I believe these will be done with a CAD layout. Timetable ??. Regards, Sean-Thomas _____________________________________________________________________ Public Seismic Network Mailing List (PSN-L) From: Edward Cranswick Subject: Re: Lehmann sensor Date: Sun, 04 Oct 1998 22:01:41 -0600 You're a funny dude; hope your knees are still good. Ted Blank wrote: > Maybe the Lehman Scale could be defined in terms of how high you have to > jump in the garage to get a standard deflection on a Lehman sensor. -- Edward Cranswick Tel: 303-273-8609 US Geological Survey, MS 966 Fax: 303-273-8600 PO Box 25046, Federal Center cranswick@........ Denver, CO 80225-0046 USA E.M. Forster said, "Only connect". _____________________________________________________________________ Public Seismic Network Mailing List (PSN-L) From: "David A. Nelson" Subject: Re: Breadboard techniques Date: Tue, 06 Oct 1998 10:44:35 +1200 At 09:06 AM 10/4/98 -0400, you wrote: >At 12:40 PM 10/3/98 -0700, you wrote: >>3) And MOST IMPORTANT (and I cannot overemphasize this point) =96 Never >>use the plain perf board with just holes or holes with solder pads >>only. Get perf board with a ground plane on one side. This advice >>applies from DC to light! The ground plane is your best protection from >>all sorts of =93squirrely=94 behavior with problems ranging from hum to >>intermittent performance.=20 I use Veroboard (perf woth copper strips ) for seismic work, building up to 3 preamp channels side by side, without any difficulty at all. As Sean said at the very low freqs involved with seismic work track to track inductance/capacitance is not a problem so therefore stability has not been a prob. In hi gain audio and RF u CANNOT use "Vero" perfboard as u will very quickly get instability. Dave Co-ordinator: New Zealand Public Seismic Network Dave A. Nelson ZL4TBN 24 Jensen St., =20 Green Is., Dunedin, =20 South Is.. New Zealand. =20 http://psn.quake.net/dave/home.htm =20 IF there indeed are other parallel universes... I can now rest in the knowledge, that in at least one of them, I am filthy rich and drive a red Ferrari _____________________________________________________________________ Public Seismic Network Mailing List (PSN-L) From: meredith lamb Subject: Re: circuit boards Date: Mon, 05 Oct 1998 21:16:12 -0600 S-T Morrissey wrote: > There is some progress in consolidating all the VBB electronics into > one or two PC cards that would be available commercially. I believe > these will be done with a CAD layout. Timetable ??. > > Regards, > Sean-Thomas > Sean-Thomas, Am probably pushing it; but can you elaborate more on this? thanks, Meredith Lamb _____________________________________________________________________ Public Seismic Network Mailing List (PSN-L) From: meredith lamb Subject: Maximumius Glutomious Alligator bites Date: Mon, 05 Oct 1998 21:41:36 -0600 Edward Cranswick, Uhhh.....is there any cure out there in Ohio, for your bites? The weather back here in Colorado was only in the 50's today, and perhaps upon your return, the cool, will sooth the ruffles? Ha. Don't hear anything of aftershocks. Afterbites? Ha. Presume they send you off anywhere for these mainland quakes. Any interesting or noteworthy history stories to pass on of your experiences? Imagine some of the storys maybe quite interesting. Do you take gobs of equipment? Government plane? Thanks, Meredith Lamb _____________________________________________________________________ Public Seismic Network Mailing List (PSN-L) From: "Rex Klopfenstein, Jr." Subject: Seismometer Pictures Date: Tue, 06 Oct 1998 18:46:29 -0400 I found several web sites that have pictures of seismometer installations and equipement. These addresses point to homepages. At the Karlsruhe site, follow the Black Forest Observatory links http://www-gpi.physik.uni-karlsruhe.de http://www.geophys.uni-stuttgart.de Rex Klopfenstein, Jr Bowling Green, OH _____________________________________________________________________ Public Seismic Network Mailing List (PSN-L) From: meredith lamb Subject: Re: Seismometer Pictures Date: Tue, 06 Oct 1998 19:20:35 -0600 Rex Klopfenstein, Jr. wrote: > I found several web sites that have pictures of seismometer > installations and equipement. These addresses point to homepages. At > the Karlsruhe site, follow the Black Forest Observatory links > > http://www-gpi.physik.uni-karlsruhe.de > > http://www.geophys.uni-stuttgart.de > Rex, Went to the Stuttgart site and saw all. Nice "find" of a site with pictures. Perhaps the most "upsetting" was the pictures of the retired seismometers and equipment; including the type of Sprengnethers I use. Seems such a waste to just store them and not use them. Too add to the days mix of photos, I just got done with some web site construction of my own vault pictures. None have the covers off, but they aren't too bad I think. http://www.geocities.com/ResearchTriangle/Facility/1739/vault.html This site only has pictures and afew words; not like the Index.html, which seems to be overloaded-ha. Thanks, Meredith Lamb _____________________________________________________________________ Public Seismic Network Mailing List (PSN-L) From: meredith lamb Subject: Easiest web site construction I've seen Date: Tue, 06 Oct 1998 20:35:19 -0600 Hi all, Been using the http://www.geocities.com free web site deal for acouple of weeks. What I have is mostly the "old" html code approach. Acouple of days ago, I tried their new "GeoBuilder" program for creating html files. With that program, you can say GOODBYE to html code typeing stuff....it is actually fun to use!! Point, click, type words...no html to enter. This is a beta program, and requires that you have a computer with at least 133mghz and 24mg of ram, and windows 95 or 98, and java capability stuff. If you're experienced with Windows 95 and file manager housekeeping stuff, this shouldn't be tough to use. Oh yes, you need Internet Explorer or Netscape versions 4.0 along with your ISP. One can make a web site using just the stuff they give you. Of course it would be enhanced with any other accessories like camera, scanner or whatnot..... The main drawback I have seen is that it seems to be toooo popular, as, their can be trouble getting through on weekdays, weekends seem to be the best time to play with the program, or perhaps late at night. The last msg mention (RE:Seismometer Pictures) of the vault.html, is a example of the GeoBuilder program. Underneath that is a huge gob of html code, that the program creates by itself. One can reduce or enlarge or move pictures without leaving the program! Soooo.....if you have the right equipment, try it out, or keep it in mind, if you're aspiring for a web site eventually. I would expect to see more programs of this nature in the near future, begin to pop up alot with other hosts. Anyway.....my seismometers are "retired".....I'am "retired"... and now, html....is "retired". How about a retread job?-ha. Meredith Lamb _____________________________________________________________________ Public Seismic Network Mailing List (PSN-L) From: barry lotz Subject: Re: Easiest web site construction I've seen Date: Tue, 06 Oct 1998 22:43:23 -0700 Hi All I was also trying to put together a web page. Has anyone got a comment/recommendation about Adobe pagemill or Claris pagemaker? I think those are the program names. I would like to avoid HTML text if possible. Thanks Barry >meredith lamb wrote: > >.... > One can make a web site using just the stuff they give you. Of > course it would be enhanced with any other accessories like > camera, scanner or whatnot..... > > The main drawback I have seen is that it seems to be toooo > popular, as, their can be trouble getting through on weekdays, > weekends seem to be the best time to play with the program, > or perhaps late at night. > _____________________________________________________________________ Public Seismic Network Mailing List (PSN-L) From: Edward Cranswick Subject: Re: Easiest web site construction I've seen Date: Wed, 07 Oct 1998 00:37:53 -0600 PSN- We used MS FrontPage'97 to make the Pymatuning EQ website: http://groundmotion.cr.usgs.gov/pym/pym.htm -Edward barry lotz wrote: > Hi All > I was also trying to put together a web page. Has anyone got a > comment/recommendation about Adobe pagemill or Claris pagemaker? I think > those are the program names. I would like to avoid HTML text if > possible. > Thanks > Barry > >meredith lamb wrote: > > > >.... > > One can make a web site using just the stuff they give you. Of > > course it would be enhanced with any other accessories like > > camera, scanner or whatnot..... > > > > The main drawback I have seen is that it seems to be toooo > > popular, as, their can be trouble getting through on weekdays, > > weekends seem to be the best time to play with the program, > > or perhaps late at night. > > > > _____________________________________________________________________ > > Public Seismic Network Mailing List (PSN-L) > > To leave this list email listserver@............. with the body of the > message: leave PSN-L -- Edward Cranswick Tel: 303-273-8609 US Geological Survey, MS 966 Fax: 303-273-8600 PO Box 25046, Federal Center cranswick@........ Denver, CO 80225-0046 USA E.M. Forster said, "Only connect". _____________________________________________________________________ Public Seismic Network Mailing List (PSN-L) From: John Hernlund Subject: Re: Easiest web site construction I've seen Date: Wed, 07 Oct 1998 09:29:41 -0700 (MST) I try to avoid using those fancy "WYSIWYG" web page makers, because there is more going on behind the scene than it seems. There is a html language war being waged by different groups and software developers. The war is market driven of course, as businesses push hard for more commerce-friendly software online. I have tried most of the programs out there, and what I found is that generally: - Some programs made pages that only worked well with certain browsers - The file size of pages made from these programs was >3X larger than mine - The programs stuck in tags, which I hate, and slip in their name - Their tag syntax for items like tables differ - Sometimes they re-size images for a default page format - They are often way overpriced! I guess I am a more old-fashioned web person, but I simply prefer the ability to telnet into a folder, make text changes, and leave fast. This saves me a lot of time. I can also work several times faster than web developers using programs like Pagemill. I also have a preference for future web page syntax; I would love to see it incorporate some items similar to TeX on unix... ****************************************************************************** John Hernlund E-mail: hernlund@....... WWW: http://www.mc.maricopa.edu/academic/phy_sci/Geology/hernlund/ http://www.public.asu.edu/~hernlund/ "It is easier to excuse an ignorant person who claims that theory is unnecessary and dispensable in his supposed practice, than to excuse a Sophist who concedes its value to the schools (as, perhaps, only a mental exercise) but who at the same time maintains that matters are quite different in practice- that as one leaves school to enter the world, one will realize one has been pursuing empty ideals and philosophical dreams- and, in a word, that what sounds good in theory is of no practical use." -Immanuel Kant, On the Proverb: That May be True in Theory, But Is of No Practical Use ****************************************************************************** _____________________________________________________________________ Public Seismic Network Mailing List (PSN-L) From: Greg Subject: Re: Easiest web site construction I've seen Date: Wed, 07 Oct 1998 17:42:03 +0000 I agree with what John H. wrote to some extent. If I had to choose a commercial program (buy one) right now, I think I'd look into Adobe Pagemill. Otherwise download (for FREE) Netscape Communicator Standard Edition, use Composer to write the page and clean it up a little by hand. Composer makes way too many tags for simple things. For example instead of a page break
sometimes it puts in
or something similar. It only makes a couple of meta tags and they are very easy to delete. One is worth keeping. It also does stuff like instead of , but they both still work. Also Composer does tend to resize images when you save the HTML. I usually correct that by hand. If you open the image in Netscape it will show the dimensions in the title bar. _________________ More on topic. I'm within weeks of buy Larry's ADC board, but I don't know about the pre-amp. I'd love to do the following (which I realize involves very little construction) 1. Get a brand new 4.5 Hz geophone and put it in a PVC pipe outside under ground a little. I'll be digging with a pick-axe if I get that far ;) I need some old work songs. 2. Put a small pre-amp in the tube with the geophone. One like Sean-Thomas uses (long battery life) 3. Convert the geophone output to fiber optic and run the fiber to the house. I want fiber optic because of lightning and the ability to extend the distance. 4. Covert back to copper at the back of the computer. I doubt all that will happen soon though. For starters I'll be using my surplus geophone from one of those $10 kits everyone bought. Maybe someday I'll finish my metal Lehman. I don't have any place to put it right now, so it doesn't matter too much. Aside from Larry's pre-amp board for the Lehmans, is there some pre-built amp that I could use for the geophone and just run the risk of lightning with copper? I don't want to have to run power to the geophone preamp AND data to the computer. With a lot more money I could probably run it with a solar panel, but... Also I'm pretty bad with a soldering iron. From the back of the computer to where I want to burry the geophone is about 20-30 ft. I can even move the computer a little closer to the wall if it would help. ,Greg _____________________________________________________________________ Public Seismic Network Mailing List (PSN-L) From: "Walt Williams" Subject: Re: Easiest web site construction I've seen Date: Wed, 7 Oct 1998 15:16:08 +0000 Hello Meridith and John Hernlund, I agree with John in his view that hand coding is best. Over the past several years and numerous sites under my belt, I personally prefer to hand code the pages. My way is the old-fashioned, 'cut-paste-upload-test/look' method. I load WSFTP (upload software), a favorite editor, I hack for awhile, upload file to my website, and look at it with my web-browser --live. Guidelines: 1 - use 800 x 600 resolution - many monitors are running this res, 2 - use a template, and hack that up, 3 - do not use tiny text, many people wear glasses, set the res for them --everybody will benefit, 4 - do not use frames, many people hate it, (is ok for catalogs) 5 - do not use fancy colors unless you test, test, and test 6 - use a spelling checker, and click & clack all of your links 7 - if you have many pictures, put them on multiple pages or better, make small clickable 'thumb-nail's and use them to load the larger pictures, more work, but infinately better, 8 - unless absolutely lossless pictures are required such as X-Ray pictures, use jpeg type compression schemes to help reduce picture size, 9 - if you want a saavy, cool site, include a TEXT-ONLY version for those folks who are using non-graphic terminals. Miscellany: 10 - include META TITLE for book-marking, 11 - include META SEARCH KEYWORDS for search engines 12 - include last modification date and your e-mail address 13 - lastly, test, test, and test. Some programs which I find are acceptable: Inprise (Borland) "IntraBuilder", HotMetal Pro (hotdog html coders choice) HotDog -- (self explanatory) Micr$oft -- FrontPage, "HTML for Dummies" was fair book on subject with lots of templates on CD. And of course, vector to NetScape for the authoratative InterNet Engineering Task Force (IETF) compliant web code tags. ---------- Shameless braggadacio....check out website Scot Stride & I made at: http://www.jpl.nasa.gov/mpfmir/rovercom/rovcom.html or mirror at: http://mars.sgi.com/rovercom/rovcom.html Best Wishes, Walt Williams, 98.10.07 dfheli@.............. ========================================================== ------- Forwarded Message Follows ------- Date: Wed, 07 Oct 1998 09:29:41 -0700 (MST) From: John Hernlund Subject: Re: Easiest web site construction I've seen To: PSN-L Mailing List Reply-to: PSN-L Mailing List I try to avoid using those fancy "WYSIWYG" web page makers, because there is more going on behind the scene than it seems. There is a html language war being waged by different groups and software developers. The war is market driven of course, as businesses push hard for more commerce-friendly software online. I have tried most of the programs out there, and what I found is that generally: - Some programs made pages that only worked well with certain browsers - The file size of pages made from these programs was >3X larger than mine - The programs stuck in tags, which I hate, and slip in their name - Their tag syntax for items like tables differ - Sometimes they re-size images for a default page format - They are often way overpriced! I guess I am a more old-fashioned web person, but I simply prefer the ability to telnet into a folder, make text changes, and leave fast. This saves me a lot of time. I can also work several times faster than web developers using programs like Pagemill. I also have a preference for future web page syntax; I would love to see it incorporate some items similar to TeX on unix... ****************************************************************************** John Hernlund E-mail: hernlund@....... WWW: http://www.mc.maricopa.edu/academic/phy_sci/Geology/hernlund/ http://www.public.asu.edu/~hernlund/ --->deletia<--- _____________________________________________________________________ Public Seismic Network Mailing List (PSN-L) From: "Rex Klopfenstein, Jr." Subject: Re: Seismometer Pictures Date: Wed, 07 Oct 1998 19:34:14 -0400 I have a question, are you using the fiberglass 'stuff' used to make air ducts for your covers? I am thinking about using the duct board as an outside cover and fill inside with several layers of foam board. The taped joints really seal out drafts and also improve the appeareance of the units. Where is your vault located? I just cut a door in my basement wall into an old cystern for a vault. It has a separate slap from the house so it is better than nothing! Now I have to clean up and paint the walls. I am planning to build a pier similar to Sean's example. I am currently machining the parts for two SG's for the E-W and N-S axis. When I get these finished with these, I'm planning build a VBB. Just starting to collect the materials and making drawings. meredith lamb wrote: > Too add to the days mix of photos, I just got done with some web > site construction of my own vault pictures. > http://www.geocities.com/ResearchTriangle/Facility/1739/vault.html > _____________________________________________________________________ Public Seismic Network Mailing List (PSN-L) From: meredith lamb Subject: Re: Easiest web site construction I've seen Date: Wed, 07 Oct 1998 18:00:52 -0600 Barry, Edward, Walt, John and Greg, Thanks for the feedback on web page makers. Seems like the heavy concensus is leaning toward Adobe Pagemill. They do have a free trial 15 day, version of it on their web site for download. http://www.adobe.com/prodindex/pagemill/demodnld.html (choice of power Macintosh or windows, but you need to fill out a form first). I went ahead and downloaded it (~14mb) plus their "getting started" manuel (~1.5mb). Briefly ran it, and in many ways its alot like the GeoBuilder program on GeoCities; but with alot more controls and choices, and explanations. One main positive is that it can be done offline, whereas GeoBuilder has ALOT to do online, and with my ISP, 20 minutes goes whipping by.....sometimes I can resume and sometimes I have to redo, if I get switched off. Too me, Netscape Composer book seems to presume that the reader already knows everything (which I don't). No outside unacqainted pre-edition suggestions readers I think. John.....liked your very extensive site...alot of great educational material there, along with alot of scenic Arizona pictures. Walt.... Yimminy Jeepers!...All those mars rover pictures that go on and on........mars exploration fans heaven! Thanks, Meredith Lamb _____________________________________________________________________ Public Seismic Network Mailing List (PSN-L) From: ralvarez@........ (Raul Alvarez) Subject: Re: Easiest web site construction I've seen Date: Wed, 7 Oct 1998 18:20:35 -0600 (MDT) Hi Meredith, Enjoyed your web page, but those COOKIES can drive you nuts. Does the geocities site allow you to turn them off? Probably not as they collect info for themselves. Raul >Hi all, > >Been using the http://www.geocities.com free web site deal >for acouple of weeks. What I have is mostly the "old" html code >approach. > > ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ "My dreams are the seeds of my reality, nurtured in the womb of my soul" RJA, 1985 Raul J. Alvarez La Estrellita Observatory Bellvue, Colorado e-mail ralvarez@........ homepage www.frii.com/~ralvarez "The Renaissance Experimenter" doing research in: Radio and Optical Astronomy, Seismology, Weather, Computers, Instrumentation and Neat Stuff! ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ _____________________________________________________________________ Public Seismic Network Mailing List (PSN-L) From: meredith lamb Subject: Re: Seismometer Pictures Date: Wed, 07 Oct 1998 19:28:13 -0600 Rex Klopfenstein, Jr. wrote: > I have a question, are you using the fiberglass 'stuff' used to make air > ducts for your covers? I am thinking about using the duct board as an > outside cover and fill inside with several layers of foam board. The taped > joints really seal out drafts and also improve the appeareance of the units. No, on the two horizontals, I used the original Sprengnethers metal frames and simply covered them with layers of commercial "ReflexTex" aluminium/plastic/airbubbles insulation. I used 3M spray glue for attachment. The lower lining is surplus rubber strips to somewhat protect the insulation. However, on the vertical cover, I had to make my own frame cover. I just used peg board, aluminium angles, metal angle brackets, spray glue, 1 layer inside (with taped joints), and 2 layers outside. I salvaged the original round metal and glass viewing porthole (zero view), and stuck that on with bolts and nuts. The side closest to the viewer is actually the access "door", using drilled and tapped screws into the aluminum and pegboard substructure. Your idea of fiberglass could well work fine; but, perhaps you would still need a metal frame to connect too. > > > Where is your vault located? I just cut a door in my basement wall into an > old cystern for a vault. It has a separate slap from the house so it is > better than nothing! Now I have to clean up and paint the walls. I am > planning to build a pier similar to Sean's example. I am currently > machining the parts for two SG's for the E-W and N-S axis. When I get these > finished with these, I'm planning build a VBB. Just starting to collect the > materials and making drawings. > My vault is in the house's crawlspace corner. That way all I had to dowas build 2 short height addtional "walls", including the entrance in one. Ended up digging down an additional 6 inches, as the piers need to be more massive, and the seismometers covers needed room to lift off for servicing on the horizontals. Hope your cistern is large enough for the pier/s you may need. If not, your basement would probably work for any possible additions. Suggest thick plastic tarp underneath the piers to keep the water from being absorbed by your pier/s, and tilting stuff results/cycles. The S-G's you're building.... are you going to use Larry's capacitive sensor circuit amplifer and general size characteristics? Personally, my giant S-G's seem to work great, and the output seems to be a very close reflection of the output of the Sprengnethers horizontals; but with few short maintenance adjustments as the piers they're on, are alot smaller than the Sprengnether piers (which I need to fix), along with the throw on single styrafoam cover-ha. Good on the STM-8 VBB plans....the vertical is very important. I use my vertical as the trigger for the lot, as it doesn't show the closeby "Lawnmower quakes"-ha. Have fun... Meredith Lamb _____________________________________________________________________ Public Seismic Network Mailing List (PSN-L) From: meredith lamb Subject: Re: Easiest web site construction I've seen Date: Wed, 07 Oct 1998 19:50:02 -0600 Raul Alvarez wrote: > Hi Meredith, > > Enjoyed your web page, but those COOKIES can drive you nuts. > Does the geocities site allow you to turn them off? Probably not > as they collect info for themselves. > > Raul > Raul, You got me there....I don't know about shutting off the "cookies". Have had experience with them with programs, but I guess overall, they don't really present too much of a problem, but, yes sometimes, they are a real nusiance....especially if ones in a hurry. So..... hows the seismograph progress going there, with or without the giant IBM voice coil magnets? Hope it is coming along. Thanks, Meredith Lamb _____________________________________________________________________ Public Seismic Network Mailing List (PSN-L) From: barry lotz Subject: Re: Easiest web site construction I've seen Date: Wed, 07 Oct 1998 20:36:12 -0700 To All Also thanks for the feedback. I think I will create a page using a composer and then hand edit it. I like that Idea. Regards Barry Greg wrote: > > I agree with what John H. wrote to some extent. If I had to choose a > commercial program (buy one) right now, I think I'd look into Adobe > Pagemill. Otherwise download (for FREE) Netscape Communicator Standard > Edition, use Composer to write the page and clean it up a little by > hand. Composer makes way too many tags for simple things. For example > instead of a page break
sometimes it puts in >
or something similar. It only makes a couple of > meta tags and they are very easy to delete. One is worth keeping. It > also does stuff like > instead of , but they both still > work. Also Composer does tend to resize images when you save the HTML. I > usually correct that by hand. If you open the image in Netscape it will > show the dimensions in the title bar. > _____________________________________________________________________ Public Seismic Network Mailing List (PSN-L) From: ralvarez@........ (Raul Alvarez) Subject: Re: Easiest web site construction I've seen Date: Thu, 8 Oct 1998 17:56:03 -0600 (MDT) >So..... hows the seismograph progress going there, with or >without the giant IBM voice coil magnets? Hope it is coming >along. > >Thanks, Meredith Lamb > Hi Meredith, Not a whole lot of progress since my last posting to my web site. (www.frii.com/~ralvarez). Been real busy with other things this summer, but looking towards snowed in days to work on it!! Won't be long here in the mountains. Raul ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ "My dreams are the seeds of my reality, nurtured in the womb of my soul" RJA, 1985 Raul J. Alvarez La Estrellita Observatory Bellvue, Colorado e-mail ralvarez@........ homepage www.frii.com/~ralvarez "The Renaissance Experimenter" doing research in: Radio and Optical Astronomy, Seismology, Weather, Computers, Instrumentation and Neat Stuff! ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ _____________________________________________________________________ Public Seismic Network Mailing List (PSN-L) From: "Walt Williams" Subject: PSN-L: Website Construction Date: Thu, 8 Oct 1998 19:46:43 +0000 Hello Raul, I visited your website, you have an agressive agenda! I love the 2-meter antenna on your "solar page", very sexy. Cool security pictures. Good luck with your STM. Walt Williams, 98.10.08 dfheli@.............. http://www.pacificnet.net/~dfheli ------- Forwarded Message Follows ------- Date: Thu, 8 Oct 1998 17:56:03 -0600 (MDT) To: PSN-L Mailing List From: ralvarez@........ (Raul Alvarez) Subject: Re: Easiest web site construction I've seen Reply-to: PSN-L Mailing List >So..... hows the seismograph progress going there, with or >without the giant IBM voice coil magnets? Hope it is coming >along. > >Thanks, Meredith Lamb > Hi Meredith, Not a whole lot of progress since my last posting to my web site. (www.frii.com/~ralvarez). Been real busy with other things this summer, but looking towards snowed in days to work on it!! Won't be long here in the mountains. Raul ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ "My dreams are the seeds of my reality, nurtured in the womb of my soul" RJA, 1985 Raul J. Alvarez La Estrellita Observatory Bellvue, Colorado e-mail ralvarez@........ homepage www.frii.com/~ralvarez "The Renaissance Experimenter" doing research in: Radio and Optical Astronomy, Seismology, Weather, Computers, Instrumentation and Neat Stuff! ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ _____________________________________________________________________ Public Seismic Network Mailing List (PSN-L) _____________________________________________________________________ Public Seismic Network Mailing List (PSN-L) From: robert barns <75612.2635@..............> Subject: Pymatuning event Date: Fri, 9 Oct 1998 11:59:09 -0400 Why was the Ohio 'quake called "Pymatuning"? Bob Barns _____________________________________________________________________ Public Seismic Network Mailing List (PSN-L) From: lahr@.................. Subject: Re: Pymatuning event Date: Fri, 9 Oct 1998 10:34:02 -0600 (MDT) > > Why was the Ohio 'quake called "Pymatuning"? > Bob Barns > > _____________________________________________________________________ The location was just south of the south end of the Pymatuning reservoir, so Ed Cranswick et al. gave it that name. JCLahr _____________________________________________________________________ Public Seismic Network Mailing List (PSN-L) From: Edward Cranswick Subject: Pymatuning aftershock Date: Fri, 09 Oct 1998 15:16:55 -0600 Bob- Did you record the Pymatuning aftershock this morning? We have a link to the CERI records at the website: http://groundmotion.cr.usgs.gov/pym/pym.htm We have also included your records of the Pymatuning EQ and the Java teleseism at the website under PSN. -Edward -- Edward Cranswick Tel: 303-273-8609 US Geological Survey, MS 966 Fax: 303-273-8600 PO Box 25046, Federal Center cranswick@........ Denver, CO 80225-0046 USA E.M. Forster said, "Only connect". _____________________________________________________________________ Public Seismic Network Mailing List (PSN-L) From: Roger Baker Subject: The Hi-Q Gravimeter/Seismograph Date: Fri, 09 Oct 1998 17:41:13 -0500 Friends,=20 I wish to proudly announce that I finally got a web page up and running that illustrates many of the details of construction of my gravimeter/seismograph design that I discussed on this list some months ago.= =20 This is one big, slow-loading, long-winded page with enough text, digital photos, drawings and charts to satisfy the most curious, I hope, and with a chart of what I believe is the 5.6 magnitude quake of 11:54 GMT off the coast of Nicaragua this morning along with charts from Albuquerque, N.M., and Hockley, Texas for comparison. To access the page use the following URL: http://www.eden.com/~rcbaker Then go to the VERY BOTTOM of my file index and click "yourpage.html" dated Oct. 9. This will slowly load the latest version from today (I haven't learned how to delete the older stuff from my server yet. Just learning!).= =20 And you bet your boots I would love to get any comments from this group, critical or otherwise. Below you will find the introduction to my page as text. --Yours, Roger Baker ************************************************************************ The Hi-Q Gravimeter/Seismometer This is an amateur scientist-friendly design for an inexpensive vertical seismometer and gravimeter, based on a high-Q magnetic spring combined with force feedback, using optical displacement detection, and all mounted within a magnetically shielded isothermal enclosure.=20 =A0 This instrument, which I call the "Hi-Q", will work as either a teleseismic vertical seismograph or as a gravimeter. Its virtues are that it is relatively small, inexpensive, and easy to build. My design utilizes a very high-Q magnetic spring suspension in combination with active magnetic feedback in an isothermal enclosure to give a frequency response that extends to DC, making it also suitable for use as a gravimeter, able to see the daily background fluctuations in earth tide.=20 The only real problem with a gravimeter being used as a seismometer is that seismometers are designed to be so sensitive to vertical acceleration that slow drift and earth tides are likely to throw the readings off scale. A seismometer usually looks for the smallest possible acceleration changes, Since gravity is physically the same as acceleration, gravimeters are merely versions of seismometers with an infinitely long period response. My instrument is capable of recording acceleration or gravitational data at a fixed location for long periods of time with minor adjustment. My instrument works to detect teleseismic events that match known events recorded by official seismic stations.=20 The principle that=A0 I use employs the repulsion and attraction between magnets as a spring force to balance the force of gravity. I prefer this approach to the metal springs more commonly used in vertical seismographs. Such high-Q systems, even with fairly short periods, are an excellent match for force feedback, because the low mechanical losses associated with high-Q systems imply that they can efficiently capture kinetic energy over periods of time much longer than their own natural frequency. This are the basic virtue needed to sense slow teleseismic events with a physically small instrument.=20 My Hi-Q is fine-tuned to remain within its proper range, i.e. to keep the sensor output from going off-scale, by shifting the position of a ceramic magnet placed on top of the instrument. This is possible because the nickel alloy shield together with a large iron pipe which surrounds the both the instrument and the isothermal enclosure does not shield it completely from external magnetic influence. However, this double shield seems to be sufficient to prevent most practical problems arising from ambient magnetic field changes.=20 The Hi-Q is designed to operate from a small three amp, 12 VDC power supply. Most of the power actually goes to supply the resistance heater needed to maintain a constant temperature set just above ambient or room temperature inside the Styrofoam insulation enclosure. The entire seismograph feedback circuit by itself requires very little power. Since ceramic magnets such as those I use for the magnetic suspension are decidedly sensitive to temperature, my design must remain at a carefully controlled constant temperature. This can be easily done with good thermal insulation and a simple feedback thermistor/ temperature regulation circuit.= =20 Since both temperature control and magnetic shielding are necessary, my experimental designs have evolved in the direction of using a short stubby beam pivoting on a horizontal knife edge that can both be contained within a vertical nickel alloy magnetic shield tube 2.5 inches in diameter and 8 inches tall surrounded by the Styrofoam insulation enclosure.=20 =A0I anticipate the basic materials, exclusive of the magnetic shield and external electronics (mostly off the shelf from Radio Shack), to cost no more than about $25. Since everything is relatively small, it could also be sealed against barometric changes by hermetically sealing it inside a glass container at near atmospheric pressure.=20 I have also made progress in building a more miniaturized version of the instrument only about an inch in diameter, which appears to be nearer in its response characteristics to a geophone, but which remains sensitive to static displacements. The latter instrument is similar to the Hi-Q but smaller, and can be made to fit in a 6 inch tall section of iron pipe, 1.5 inch ID. Such a configuration is very compact and, with suitable adjustments, can be used at any angle from the vertical. My thinking is that the latter design is small enough so that these could be tilted at about a 45 degree angle and mounted in a common isothermal enclosure for full three axis recording with one instrument. For example, four of these could be aligned along the edges of a four-sided pyramid, and the outputs from opposite pairs of outputs added in such a way as to be able to calculate quake shocks as three-dimensional vectors of acceleration force. With computing power being relatively cheap, this should be practical.=20 *************************************************************************** _____________________________________________________________________ Public Seismic Network Mailing List (PSN-L) From: meredith lamb Subject: Re: The Hi-Q Gravimeter/Seismograph Date: Fri, 09 Oct 1998 21:29:44 -0600 Roger Baker, Congratulations on your new web site! Looks like one heck of a lot of work on your part. Magnificent mechanical drawing! Do suggest that the text be black instead of blue; kind of hard to read. (I also have Netscape) Its going to take awhile to read.......but.....in the meantime...... thanks for the huge data! Meredith Lamb _____________________________________________________________________ Public Seismic Network Mailing List (PSN-L) From: "Charles R. Patton" Subject: Re: The Hi-Q Gravimeter/Seismograph Date: Fri, 09 Oct 1998 21:59:38 -0700 Roger, I too, want to congratulate you on your site. And I too have to mirror Meredith=92s comment about the text. My old eyes have a hard time readin= g the light blue on black (Netscape 4.06 at work and 4.04 at home). Additionally, when I printed out the pages at work, the photos came through great on a B&W HP5SI at 600 dpi, but the text prints out in gray, making it hard to read on paper too. Keep up the good work, Charles R. Patton _____________________________________________________________________ Public Seismic Network Mailing List (PSN-L) From: Roger Baker Subject: Re: The Hi-Q Gravimeter/Seismograph Date: Sat, 10 Oct 1998 01:13:39 -0500 OK OK, I hear you guys. I wanted something to set off the photos a little and black is great for that at least. Since the text is long, maybe I'll try black on pale green or something easy on the eyes like that. Meanwhil= e, I think you can go to the edit button on the browser toolbar and down to "select all" and then dump it in a text file like Word. Details, details.= ... Meanwhile, what I want most is for somebody to get curious enough to replicate and improve the thing now that they can see that it exists and probably does work, and is fairly easy to build, and so on. But thats mostly behind me now; the next personal challenge is all the other instruments that need designing and building. I have years of good stuff that it would be neat to put up on a Science Hacker web page. Like how to gold plate the surface of water, to mention one interesting phenomenon I discovered a few years back, plus lots of others... --Yours, Roger =20 =20 *************************************************************************= * At 09:59 PM 10/9/98 -0700, you wrote: >Roger, >I too, want to congratulate you on your site. And I too have to mirror >Meredith=92s comment about the text. My old eyes have a hard time readi= ng >the light blue on black (Netscape 4.06 at work and 4.04 at home). >Additionally, when I printed out the pages at work, the photos came >through great on a B&W HP5SI at 600 dpi, but the text prints out in >gray, making it hard to read on paper too. > >Keep up the good work, >Charles R. Patton > > > >_____________________________________________________________________ > >Public Seismic Network Mailing List (PSN-L) > >To leave this list email listserver@............. with the body of the=20 >message: leave PSN-L > _____________________________________________________________________ Public Seismic Network Mailing List (PSN-L) From: GeE777@....... Subject: Re: The Hi-Q Gravimeter/Seismograph Date: Sat, 10 Oct 1998 12:39:02 EDT Hi Roger and All I have built a gravitymeter using a vertical geophone. The geophone has the same equipment that a gravity meter has, a mass, the coil, suspended on a spring. I applied a voltage to the geophone coil to deflect the coil till the coil hit the stop at the end of the coil travel space. An electronic switch removes the voltage from the coil and hooks the coil output to a recording device, a digital oscillascope. The coil, returning to its natural at rest position, outputs a pulse. The voltage of that pulse is determined by the distance the coil travels within the geophone magnetic field to the at rest position. If the gravity is greater. the coil will be at rest lower in the coil travel area. If the voltage raises the coil to the top of the travel area, the resulting pulse will be larger. To make it more sensitive, I applied an opposite polarity voltage to the coul to deflect it to the lower stop. With more gravity, the resulting pulse will be lower voltage. I then subtract this pulse from the pulse caused by the coil deflected up I have recorded earth tides with this device. Temperature sensitive? yes! I have been hand calculating the temperature effects out of the results. I am building a gravitymeter using four geophones, two connected to the output in the opposite polarity to reduce the effect of seismic noise. This model is almost ready for testing. George Erich Seismic Exploration Acquisition Consultant P. O. Box 2011, Norwalk, CA 90650, U. S. A. Phone (562) 868-6013 e-mail GeE777@....... 33 53.90N 118 04.53W _____________________________________________________________________ Public Seismic Network Mailing List (PSN-L) From: bzimmerman@............ Subject: Re: Pymatuning aftershock Date: Sat, 10 Oct 1998 13:02:15 -0500 (EST) Edward: No, I did not record the Pymatuning aftershock here in Edinboro. I spoke with Nano Seeber who thought it looked like about an M1 event. I would not expect to pick up an event that small considering I am about 50 km from the epicenter. Guess its time to start thinking about some more sophisticated equipment. Thanks for posting those records. On Fri, 9 Oct 1998, Edward Cranswick wrote: Brian Zimmerman > Did you record the Pymatuning aftershock this morning? We have a > link to the CERI records at the website: > > http://groundmotion.cr.usgs.gov/pym/pym.htm > > We have also included your records of the Pymatuning EQ and the Java > teleseism at the website under PSN. > -Edward > > -- > Edward Cranswick Tel: 303-273-8609 > US Geological Survey, MS 966 Fax: 303-273-8600 > PO Box 25046, Federal Center cranswick@........ > Denver, CO 80225-0046 USA E.M. Forster said, "Only connect". > > > > _____________________________________________________________________ > > Public Seismic Network Mailing List (PSN-L) > > To leave this list email listserver@............. with the body of the > message: leave PSN-L > _____________________________________________________________________ Public Seismic Network Mailing List (PSN-L) From: "David A. Nelson" Subject: LARGE QUAKE NOW Date: Mon, 12 Oct 1998 12:00:43 +1200 00:50 UTC 12 Oct 98 recording very large anplitude long period waves in Dunedin NZ Dave Co-ordinator: New Zealand Public Seismic Network Dave A. Nelson ZL4TBN 24 Jensen St., Green Is., Dunedin, South Is.. New Zealand. http://psn.quake.net/dave/home.htm IF there indeed are other parallel universes... I can now rest in the knowledge, that in at least one of them, I am filthy rich and drive a red Ferrari _____________________________________________________________________ Public Seismic Network Mailing List (PSN-L) From: "Francesco" Subject: R: LARGE QUAKE NOW Date: Mon, 12 Oct 1998 01:07:54 +0100 Until now, no signal from Italy stations. Francesco _____________________________________________________________________ Public Seismic Network Mailing List (PSN-L) From: meredith lamb Subject: Re: A Gravity meter using 4 Geophones Date: Sun, 11 Oct 1998 18:24:52 -0600 GeE777@....... wrote: > I have recorded earth tides with this device. Temperature sensitive? yes! I > have been hand calculating the temperature effects out of the results. I am > building a gravitymeter using four geophones, two connected to the output in > the opposite polarity to reduce the effect of seismic noise. This model is > almost ready for testing. > > George Erich > George Erich, I'd be very interested to hear/see more results of your combined 4 geophone instrument. What brand, frequency are you using? Seems like I recall Larry Cochrane using 2 geophones with a type of comparator electronics for regular seismic monitoring. Anyway, I hope the results are positive and its possible for you to submit the details somehow, sometime. Thanks for the new stuff! -- Meredith Lamb <><><><><><><><><><><><><><><><><><><><><><><><><><><><><><><><><><><><> Main Web site: http://www.users.uswest.net/~psnseismograph52/Index.html and secondary site: http://www.geocities.com/ResearchTriangle/Facility/1739/index.html <><><><><><><><><><><><><><><><><><><><><><><><><><><><><><><><><><><><> _____________________________________________________________________ Public Seismic Network Mailing List (PSN-L) From: "David A. Nelson" Subject: Re large quake Date: Mon, 12 Oct 1998 12:36:50 +1200 00:50 UTC 12 Oct 98 recording very large anplitude long period waves >in Dunedin NZ >Dave Update ....... lookes like the quake is between me and antartica, and prob closer to me. The aslwww seismogram from Scott Base Antartica shows the best record and an early estimate of the event size is between M5.5 and M6.0 this puts the quake within 1500 km odd of me the geophones didnt show it but strong low freq S and Surface waves on my recorder indicate that its probably a shallow event ie. 33km or less. It appeares to have been followed by an aftershock some 15 minutes later Dave Co-ordinator: New Zealand Public Seismic Network Dave A. Nelson ZL4TBN 24 Jensen St., Green Is., Dunedin, South Is.. New Zealand. http://psn.quake.net/dave/home.htm IF there indeed are other parallel universes... I can now rest in the knowledge, that in at least one of them, I am filthy rich and drive a red Ferrari _____________________________________________________________________ Public Seismic Network Mailing List (PSN-L) From: GeE777@....... Subject: Re: A Gravity meter using 4 Geophones Date: Sun, 11 Oct 1998 21:29:15 EDT Hello All One thing I failed to mention if someone wants to try this. When the voltage to deflect the coil is removed there is a strong short spike resulting from the emf collapsing around the coil. You don't want this as it is much stronger than the wavelet generated by the coil coming to rest. The electronic switch closed the circuit between the coil and the recording device after the spike and before the wavelet generated by the coil movement. To reduce errors, level the phone carefully and always keep on the same azimuth. I got 10 HZ phones But would like to try 4.5 HZ. In a message dated 10/11/98 5:31:31 PM Pacific Daylight Time, psnseismograph52@.......... writes: << I'd be very interested to hear/see more results of your combined 4 geophone instrument. What brand, frequency are you using? >> George Erich Seismic Exploration Acquisition Consultant P. O. Box 2011, Norwalk, CA 90650, U. S. A. Phone (562) 868-6013 e-mail GeE777@....... 33 53.90N 118 04.53W _____________________________________________________________________ Public Seismic Network Mailing List (PSN-L) From: John Hernlund Subject: Re: A Gravity meter using 4 Geophones Date: Sun, 11 Oct 1998 18:50:01 -0700 (MST) George, Excellent device!!! How accurate is it? milligals or microgals? What if you wanted to build a nanogal gravimeter? Do such things exist? ****************************************************************************** John Hernlund E-mail: hernlund@....... WWW: http://www.mc.maricopa.edu/academic/phy_sci/Geology/hernlund/ http://www.public.asu.edu/~hernlund/ "It is easier to excuse an ignorant person who claims that theory is unnecessary and dispensable in his supposed practice, than to excuse a Sophist who concedes its value to the schools (as, perhaps, only a mental exercise) but who at the same time maintains that matters are quite different in practice- that as one leaves school to enter the world, one will realize one has been pursuing empty ideals and philosophical dreams- and, in a word, that what sounds good in theory is of no practical use." -Immanuel Kant, On the Proverb: That May be True in Theory, But Is of No Practical Use ****************************************************************************** _____________________________________________________________________ Public Seismic Network Mailing List (PSN-L) From: barry lotz Subject: Re: Re large quake Date: Sun, 11 Oct 1998 19:17:02 -0700 Dave I picked up moderate waves in California foothills @ 00:20:18 UTC also Barry David A. Nelson wrote: > > 00:50 UTC 12 Oct 98 recording very large anplitude long period waves > >in Dunedin NZ > >Dave > > Update ....... > > lookes like the quake is between me and antartica, and prob closer to me. > The aslwww seismogram from Scott Base Antartica shows the best record > and an early estimate of the event size is between M5.5 and M6.0 > > this puts the quake within 1500 km odd of me the geophones didnt show it > but strong low freq S and Surface waves on my recorder indicate that > its probably a shallow event ie. 33km or less. > > It appeares to have been followed by an aftershock some 15 minutes later > > Dave _____________________________________________________________________ Public Seismic Network Mailing List (PSN-L) From: "J. D. Cooley" Subject: Re: Re large quake Date: Sun, 11 Oct 1998 20:22:40 -0700 Recent automated solutions from the International Data Centre: B Date Time Lat Lon Nph Depth Mag Region a 1998/10/12 00:28:49.0 18.31N 145.82E 7 267.2 mb 3.4 Mariana Islands a 1998/10/11 23:57:30.3 56.21S 143.31W 13 mb 4.7 Pacific-Antarctic Ridge a 1998/10/11 23:36:24.6 56.76S 142.77W 11 mb 4.7 Pacific-Antarctic Ridge a 1998/10/11 21:45:22.4 27.38S 62.55W 8 mb 4.7 Santiago Del Estero Prov., Arg. a 1998/10/11 21:43:13.8 27.72S 63.69W 16 mb 5.6 Santiago Del Estero Prov., Arg. I don't see the Mb5.6 on the aslwww seismograms, but certainly see the Pacific-Antarctic Ridge. At 07:17 PM 10/11/98 -0700, you wrote: >Dave > I picked up moderate waves in California foothills @ 00:20:18 UTC >also > Barry > > >David A. Nelson wrote: >> >> 00:50 UTC 12 Oct 98 recording very large anplitude long period waves >> >in Dunedin NZ >> >Dave >> >> Update ....... >> >> lookes like the quake is between me and antartica, and prob closer to me. >> The aslwww seismogram from Scott Base Antartica shows the best record >> and an early estimate of the event size is between M5.5 and M6.0 >> >> this puts the quake within 1500 km odd of me the geophones didnt show it >> but strong low freq S and Surface waves on my recorder indicate that >> its probably a shallow event ie. 33km or less. >> >> It appeares to have been followed by an aftershock some 15 minutes later >> >> Dave > >_____________________________________________________________________ > >Public Seismic Network Mailing List (PSN-L) > >To leave this list email listserver@............. with the body of the >message: leave PSN-L > > _____________________________________________________________________ Public Seismic Network Mailing List (PSN-L) From: barry lotz Subject: Red Puma Date: Sun, 11 Oct 1998 21:00:35 -0700 I lost the bookmark. Could someone pass it to me? Thanks Barry _____________________________________________________________________ Public Seismic Network Mailing List (PSN-L) From: peaches@............ (Donna Whitaker) Subject: Re: Red Puma Date: Sun, 11 Oct 1998 18:12:15 -1000 (HST) Barry, http://seismo.ethz.ch/redpuma/redpuma_ami_list.html >I lost the bookmark. Could someone pass it to me? > Thanks > Barry > >_____________________________________________________________________ > >Public Seismic Network Mailing List (PSN-L) > >To leave this list email listserver@............. with the body of the >message: leave PSN-L > > _____________________________________________________________________ Public Seismic Network Mailing List (PSN-L) From: meredith lamb Subject: Re: Red Puma Date: Sun, 11 Oct 1998 22:11:00 -0600 barry lotz wrote: > I lost the bookmark. Could someone pass it to me? > Thanks > Barry > http://seismo.ethz.ch/redpuma/redpuma-ami-list.html Use_ where- is shown. -- Meredith Lamb <><><><><><><><><><><><><><><><><><><><><><><><><><><><><><><><><><><><> Main Web site: http://www.users.uswest.net/~psnseismograph52/Index.html and secondary site: http://www.geocities.com/ResearchTriangle/Facility/1739/index.html <><><><><><><><><><><><><><><><><><><><><><><><><><><><><><><><><><><><>  

barry lotz wrote:

I lost the bookmark. Could someone pass it to me?
                    &nb sp;                    &nbs p; Thanks
                    &nb sp;                    &nbs p;   Barry
 
http://seismo.ethz.ch/redpuma/redpuma-ami-list.html
Use_ where- is shown.

--
Meredith Lamb
<><><><><><><><><><><><><><><><><><><><><><><><>< ;><><><><><><><><><><><>
Main Web site:  http://www.users.uswest.net/~psnsei smograph52/Index.html
                    &nb sp;         and secondary site:
   http://www.geocities.com/Research Triangle/Facility/1739/index.html
<><><><><><><><><><><><><><><><><><><><><><><><>< ;><><><><><><><><><><><>
  From: barry lotz Subject: Re: Red Puma Date: Sun, 11 Oct 1998 21:23:47 -0700 Thanks much! Barry >Donna Whitaker wrote: > > Barry, > > http://seismo.ethz.ch/redpuma/redpuma_ami_list.html > _____________________________________________________________________ Public Seismic Network Mailing List (PSN-L) From: GeE777@....... Subject: Re: A Gravity meter using 4 Geophones Date: Mon, 12 Oct 1998 05:34:51 EDT Hi John & All I started experimenting with this in my lab just before my retirement. Then I was called away to another job. I know that everything seemed to interfere with my results. Movement, rotating, etc. In a message dated 10/11/98 6:51:01 PM Pacific Daylight Time, hernlund@....... writes: << George, Excellent device!!! How accurate is it? milligals or microgals? What if you wanted to build a nanogal gravimeter? Do such things exist? >> <> George Erich Seismic Exploration Acquisition Consultant P. O. Box 2011, Norwalk, CA 90650, U. S. A. Phone (562) 868-6013 e-mail GeE777@....... 33 53.90N 118 04.53W _____________________________________________________________________ Public Seismic Network Mailing List (PSN-L) From: "J. D. Cooley" Subject: Large quake Date: Mon, 12 Oct 1998 05:02:08 -0700 It is interesting that the quake that occurred at approx. 23:50 UTC on 10/11/98 has not been reported by any agency (except the IDC) even though it has been over 12 hours now! I realize that the guys/gals at USGS are in bed, but usually there are a few automated, at least, solutions posted to RedPuma with a quake this size. Just observing! "JD" _____________________________________________________________________ Public Seismic Network Mailing List (PSN-L) From: "David A. Nelson" Subject: Re: Large quake Date: Tue, 13 Oct 1998 07:18:54 +1200 At 05:02 AM 10/12/98 -0700, you wrote: >It is interesting that the quake that occurred at approx. 23:50 UTC on >10/11/98 has not been reported by any agency (except the IDC) even though it has been over 12 hours now! >I realize that the guys/gals at USGS are in bed, but usually there are a few >automated, at least, solutions posted to RedPuma with a quake this size. >Just observing! >"JD" yeah !!! its common for that to happen wit h quakes in my part of the world. there are many M5-M6 and a reasonable munber of M6++ events that NEVER show up on the NEIC listings. I find it frustrating but as there is nothing i can do abt it i jst live with it. Yesterday's event that u speak of worked out to be ~Ms5.8 + - 0.2 as recorded on my SDR system. i apologise for the time error i reported yesterday too, i was 1 hr in advance, we jst changed to daylite time and i looked at the wrong clock (smile) my i hate daylight saving time !! Dave Co-ordinator: New Zealand Public Seismic Network Dave A. Nelson ZL4TBN 24 Jensen St., Green Is., Dunedin, South Is.. New Zealand. http://psn.quake.net/dave/home.htm IF there indeed are other parallel universes... I can now rest in the knowledge, that in at least one of them, I am filthy rich and drive a red Ferrari _____________________________________________________________________ Public Seismic Network Mailing List (PSN-L) From: S-T Morrissey Subject: Gravimeters Date: Mon, 12 Oct 1998 18:31:04 -0500 (CDT) Re: high resolution gravimeters The most recent commercial gravimeters have nanogal resolution at about 1/nanodollar prices. Some are absolute meters, the more clever of which tracks a falling corner cube reflector with a lasar interferometer to measure the acceleration of G. It is curious to "hear" it "plink" away while at work, as a little elevator device raises the cube in the vacuum column and drops it repeatedly about every 10 seconds. The lasar interferometer uses a reference mass on a "superspring" in the base to eliminate seismic disturbances. A computer does the statistics in real time, as well as correcting for environmental noise (temperature, etc.) After about 24 hours, sub-microgal noise levels are realized. For reference, earth tides are of the order of 100 to 200 microgals, where a microgal is an acceleration of 10^-8 m/sec^2. The instrument costs in excess of $100k. The highest resolution instruments levitate a superconducting sphere to measure G. A combination of magnetic and electrostatic feedback make detection levels of less than 1 nanogal (10^-11 m/sec^2) possible, with noise level power spectra of 10^-3 microgal^2 per cycle/hour possible at periods longer than 0.2 cycle/hour. With these instruments, many natural effects have to be removed, including the solid earth tides, ocean loading, barometric loading (0.3 microgal/millibar), etc. More affordable instruments are realized by incorporating electrostatic feedback into LaCoste-style instruments. Even the best Broadband vertical seismometer, the STS-1V, produces earth-tide data with microgal resolution, and its ultra long period seismic data is useful for studying the gravitational oscillations of the earth excited by large earthquakes. At the IRIS stations, the 24-bit digitizer resolution of the ULP data (at 150 seconds) is about 100 counts / microgal. The long period (20 to 60 second) surface waves produced by moderate (M=6 +) quakes are often about the amplitude of the earth tides. at 150 seconds. Regards, Sean-Thomas _____________________________________________________________________ Public Seismic Network Mailing List (PSN-L) From: John Hernlund Subject: Re: Large quake Date: Mon, 12 Oct 1998 17:35:04 -0700 (MST) On Tue, 13 Oct 1998, David A. Nelson wrote: > >I realize that the guys/gals at USGS are in bed, but usually there are a few > >automated, at least, solutions posted to RedPuma with a quake this size. > yeah !!! its common for that to happen wit h quakes in my part of the > world. there are many M5-M6 and a reasonable munber of M6++ events that > NEVER show up on the NEIC listings. I find it frustrating but as there is > nothing i can do abt it i jst live with it. This worries me, because I like to work with statistical analysis of seismicity, which depends very strongly on the accuracy, thoroughness, and coverage of the collected data. But, like you said, we get what we get... > Yesterday's event that u speak of worked out to be ~Ms5.8 + - 0.2 as > recorded on my SDR system. We all need more stations all over the globe to improve coverage. It would be nice to have as many stations as would be needed so that no magnitude 2.0 or greater event would escape detection anywhere... But we are probably talking mega-bucks here... ****************************************************************************** John Hernlund E-mail: hernlund@....... WWW: http://www.mc.maricopa.edu/academic/phy_sci/Geology/hernlund/ http://www.public.asu.edu/~hernlund/ "It is easier to excuse an ignorant person who claims that theory is unnecessary and dispensable in his supposed practice, than to excuse a Sophist who concedes its value to the schools (as, perhaps, only a mental exercise) but who at the same time maintains that matters are quite different in practice- that as one leaves school to enter the world, one will realize one has been pursuing empty ideals and philosophical dreams- and, in a word, that what sounds good in theory is of no practical use." -Immanuel Kant, On the Proverb: That May be True in Theory, But Is of No Practical Use ****************************************************************************** _____________________________________________________________________ Public Seismic Network Mailing List (PSN-L) From: S-T Morrissey Subject: Re: Geophone amps Date: Mon, 12 Oct 1998 19:41:46 -0500 (CDT) Greg, The micropower seismic preamp that we use here (I assume you saw my description of it, which I can repeat if necessary) has been made here and elsewhere, and was also made by Sprengnether at one time. I think they still make a pre-amp, but I don't know if it is micro-power. (www.sprengnether.com). The amplifier is simple enough that it can even be made on a perforated PC board in a few hours with just two MC1776 Amps, but using fixed gain/filter stages for simplicity and be able to run from photo-lithium batteries for a few years. I guess I could just do it and document it if there is any interest. The battery operation greatly simplifies the remote installation. I actually have several versions of the 4 amplifier design that were made by students on perf-board to fit inside the 1" diameter case of hydrophones (we once tried to detect tidal strains by using an air-gun in a well and timing the seismic pulse to stations several kilometers away). Maybe I should photograph the board and post it with documentation. The only consideration for use with a geophone is that more gain will be needed. We use 60 db (x 1000) and up with a L4-C with a 100v/m/sec pad. A geophone may need 10x more gain. The pre-amp can be configured for 80db, or x100 per stage, Its filters can also be made low pass at 1 hz or less to provide more response to distant earthquakes. Regards, Sean-Thomas _____________________________________________________________________ Public Seismic Network Mailing List (PSN-L) From: S-T Morrissey Subject: Re: Large quake Date: Mon, 12 Oct 1998 19:54:23 -0500 (CDT) In the defense of the USGS, I don't think that they have recently missed cataloging any magnitude 6 earthquake. The NEIS HAS listed the events near the Pacific-Antartic ridge of Oct. 11, at magnitudes 5.7 and 5.5, as well as a rare event this morning near the Artic circle, a M=4.8 north of Severnaya Zemlya. I believe that their current global catalogue is quite complete for events greater than magnitude 5. On the other hand, the earth could still use better coverage with calibrated broadband stations, which is where the PSN can make a serious scientific contribution. Regards, Sean-Thomas _____________________________________________________________________ Public Seismic Network Mailing List (PSN-L) From: "David A. Nelson" Subject: Re: Large quake Date: Tue, 13 Oct 1998 14:28:11 +1200 At 07:54 PM 10/12/98 -0500, you wrote: >In the defense of the USGS, I don't think that they have recently missed >cataloging any magnitude 6 earthquake. The NEIS HAS listed the events >near the Pacific-Antartic ridge of Oct. 11, at magnitudes 5.7 and >5.5, as well as a rare event this morning near the Artic circle, >a M=4.8 north of Severnaya Zemlya. I believe that their current >global catalogue is quite complete for events greater than magnitude 5. >On the other hand, the earth could still use better coverage with >calibrated broadband stations, which is where the PSN can make a >serious scientific contribution. >Regards, >Sean-Thomas Sorry Sean i have to STRONGLY dispute that as said in my previous e-mail there are many M5 - M6 and the occassional M6+ event in this part of the world that goes unnoticed. i could produce quite a substantial list of these events over even the last 10 yrs since i have been seriously involved in seismic recording. here is one example that didnt make it to the NEIC listing..... 210498 1134 6.3 39.02S 174.92E, 245KD, 33 km WSW of Taumarunui, Felt from Christchurch to Taranaki and Hawke's Bay. Shaking felt for about 45 seconds in Wellington (New Zealand) the only M6+ event onland in NZ so far this yr and it was missed IDC did log it but at a ridiculously low magnitude and very poor location now there have been at least 5 x M5.0 + events this yr alone that didnt make it to the NEIC d/m/y NZST Mb Lat Long Depth 090298 0626 5.3 45.06S 170.47E, 12KD, 250298 0517 5.4 41.92S 174.19E, 21KD, 250398 2018 5.0 38.29S 176.29E, 05KD, 060598 2056 5.0 44.91S 167.97E, 33KD, 140598 2127 5.0 38.47S 177.17E, 58KD, now this isnt all the NEIC's fault, from observations... the NZ seismo observatory dont seem to get the info passed on to the USA agencies very well. WHY ?? i dont know jst seems to be a lack of communications. im jst an amateur *smile* Dave Co-ordinator: New Zealand Public Seismic Network Dave A. Nelson ZL4TBN 24 Jensen St., Green Is., Dunedin, South Is.. New Zealand. http://psn.quake.net/dave/home.htm IF there indeed are other parallel universes... I can now rest in the knowledge, that in at least one of them, I am filthy rich and drive a red Ferrari _____________________________________________________________________ Public Seismic Network Mailing List (PSN-L) From: Edward Cranswick Subject: Re: Large quake Date: Mon, 12 Oct 1998 21:07:40 -0600 Thank you, Sean-Thomas. S-T Morrissey wrote: > In the defense of the USGS, I don't think that they have recently missed > cataloging any magnitude 6 earthquake. The NEIS HAS listed the events > near the Pacific-Antartic ridge of Oct. 11, at magnitudes 5.7 and > 5.5, as well as a rare event this morning near the Artic circle, > a M=4.8 north of Severnaya Zemlya. I believe that their current > global catalogue is quite complete for events greater than magnitude 5. > > On the other hand, the earth could still use better coverage with > calibrated broadband stations, which is where the PSN can make a > serious scientific contribution. > > Regards, > Sean-Thomas > > _____________________________________________________________________ > > Public Seismic Network Mailing List (PSN-L) > > To leave this list email listserver@............. with the body of the > message: leave PSN-L -- Edward Cranswick Tel: 303-273-8609 US Geological Survey, MS 966 Fax: 303-273-8600 PO Box 25046, Federal Center cranswick@........ Denver, CO 80225-0046 USA E.M. Forster said, "Only connect". _____________________________________________________________________ Public Seismic Network Mailing List (PSN-L) From: Edward Cranswick Subject: Re: Large quake Date: Mon, 12 Oct 1998 21:14:09 -0600 Dave- Interesting observations. I'll pass them along. -Edward David A. Nelson wrote: > At 07:54 PM 10/12/98 -0500, you wrote: > >In the defense of the USGS, I don't think that they have recently missed > >cataloging any magnitude 6 earthquake. The NEIS HAS listed the events > >near the Pacific-Antartic ridge of Oct. 11, at magnitudes 5.7 and > >5.5, as well as a rare event this morning near the Artic circle, > >a M=4.8 north of Severnaya Zemlya. I believe that their current > >global catalogue is quite complete for events greater than magnitude 5. > >On the other hand, the earth could still use better coverage with > >calibrated broadband stations, which is where the PSN can make a > >serious scientific contribution. > >Regards, > >Sean-Thomas > > Sorry Sean i have to STRONGLY dispute that as said in my previous > e-mail there are many M5 - M6 and the occassional M6+ event in this part > of the world that goes unnoticed. > > i could produce quite a substantial list of these events over even the > last 10 yrs since i have been seriously involved in seismic recording. > > here is one example that didnt make it to the NEIC listing..... > > 210498 1134 6.3 39.02S 174.92E, 245KD, 33 km WSW of Taumarunui, Felt > from Christchurch to Taranaki and Hawke's Bay. Shaking felt for about 45 > seconds in Wellington (New Zealand) > > the only M6+ event onland in NZ so far this yr and it was missed > IDC did log it but at a ridiculously low magnitude and very poor location > > now there have been at least 5 x M5.0 + events this yr alone that > didnt make it to the NEIC > > d/m/y NZST Mb Lat Long Depth > 090298 0626 5.3 45.06S 170.47E, 12KD, > 250298 0517 5.4 41.92S 174.19E, 21KD, > 250398 2018 5.0 38.29S 176.29E, 05KD, > 060598 2056 5.0 44.91S 167.97E, 33KD, > 140598 2127 5.0 38.47S 177.17E, 58KD, > > now this isnt all the NEIC's fault, from observations... the NZ > seismo observatory dont seem to get the info passed on to the USA > agencies very well. WHY ?? i dont know jst seems to be a lack of > communications. > im jst an amateur *smile* > > Dave > > Co-ordinator: > New Zealand > Public Seismic Network > Dave A. Nelson ZL4TBN > 24 Jensen St., > Green Is., Dunedin, > South Is.. New Zealand. > > http://psn.quake.net/dave/home.htm > > IF there indeed are other parallel universes... I can now rest in the > knowledge, that in at least one of them, I am filthy rich and drive a red > Ferrari > > _____________________________________________________________________ > > Public Seismic Network Mailing List (PSN-L) > > To leave this list email listserver@............. with the body of the > message: leave PSN-L -- Edward Cranswick Tel: 303-273-8609 US Geological Survey, MS 966 Fax: 303-273-8600 PO Box 25046, Federal Center cranswick@........ Denver, CO 80225-0046 USA E.M. Forster said, "Only connect". _____________________________________________________________________ Public Seismic Network Mailing List (PSN-L) From: "James M Hannon" Subject: Re: Large quake Date: Tue, 13 Oct 1998 07:26:57 -0500 That explains why I was confused. I looked at my watch and thought either my watch was set wrong or you had discovered a new way to predict quakes :)! Jim Hannon "David A. Nelson" on 10/12/98 02:18:54 PM Please respond to PSN-L Mailing List To: PSN-L Mailing List cc: Subject: Re: Large quake i apologise for the time error i reported yesterday too, i was 1 hr in advance, we jst changed to daylite time and i looked at the wrong clock (smile) my i hate daylight saving time !! Dave Co-ordinator: New Zealand Public Seismic Network Dave A. Nelson ZL4TBN 24 Jensen St., Green Is., Dunedin, South Is.. New Zealand. _____________________________________________________________________ _____________________________________________________________________ Public Seismic Network Mailing List (PSN-L) From: "J. D. Cooley" Subject: Re: Large quake Date: Tue, 13 Oct 1998 06:39:27 -0700 At 02:28 PM 10/13/98 +1200, you wrote: [good sized snip] > >here is one example that didnt make it to the NEIC listing..... > >210498 1134 6.3 39.02S 174.92E, 245KD, 33 km WSW of Taumarunui, Felt >from Christchurch to Taranaki and Hawke's Bay. Shaking felt for about 45 >seconds in Wellington (New Zealand) The University of Washington (IRIS) has data and some very impressive seismograms of a quake occurring on (using your convention for date): 200498 23:34:13.0 38.31S 173.8E 245KD M5.5 Could this be the quake you are referring to? I don't know if the USGS has it in any of their listings, but the most impressive seismogram of this quake was by CTAO which is listed as: Charters Towers, Queensland, Australia and below that is: IRIS-USGS. It also says that this seismometer is on the BRS Network which is the University of Queensland, Brisbane, Australia. I didn't check the other quakes you listed below, just the one. "JD" > > the only M6+ event onland in NZ so far this yr and it was missed > IDC did log it but at a ridiculously low magnitude and very poor location > > now there have been at least 5 x M5.0 + events this yr alone that >didnt make it to the NEIC > >d/m/y NZST Mb Lat Long Depth >090298 0626 5.3 45.06S 170.47E, 12KD, >250298 0517 5.4 41.92S 174.19E, 21KD, >250398 2018 5.0 38.29S 176.29E, 05KD, >060598 2056 5.0 44.91S 167.97E, 33KD, >140598 2127 5.0 38.47S 177.17E, 58KD, > > now this isnt all the NEIC's fault, from observations... the NZ >seismo observatory dont seem to get the info passed on to the USA >agencies very well. WHY ?? i dont know jst seems to be a lack of >communications. > im jst an amateur *smile* > >Dave > _____________________________________________________________________ Public Seismic Network Mailing List (PSN-L) From: taber@............. (John Taber) Subject: Re: Large quake Date: Wed, 14 Oct 1998 12:25:50 +1300 Dave Nelson wrote: >Sorry Sean i have to STRONGLY dispute that as said in my previous >e-mail there are many M5 - M6 and the occassional M6+ event in this part >of the world that goes unnoticed. > > i could produce quite a substantial list of these events over even the >last 10 yrs since i have been seriously involved in seismic recording. > >here is one example that didnt make it to the NEIC listing..... > >210498 1134 6.3 39.02S 174.92E, 245KD, 33 km WSW of Taumarunui, Felt >from Christchurch to Taranaki and Hawke's Bay. Shaking felt for about 45 >seconds in Wellington (New Zealand) > > the only M6+ event onland in NZ so far this yr and it was missed > IDC did log it but at a ridiculously low magnitude and very poor location > >now this isnt all the NEIC's fault, from observations... the NZ >seismo observatory dont seem to get the info passed on to the USA >agencies very well. WHY ?? i dont know jst seems to be a lack of >communications. I think there are several reasons that earthquakes from the southwest Pacific don't show up in the NEIC catalogue. The first is that as Dave mentioned, NEIC magnitudes are lower than NZ local magnitudes. For example, the IRIS magnitude for the above event is 5.5 (note that the above time and date is NZDT, it's 200498 2334 UTC). I don't know the reason for the mismatch, but I think the NZ local magnitude gives a better estimate of the moment magnitude than does the NEIC magnitude. This means that many events in the M5-6 range according to the NZ scale are below M5 on the NEIC scale and so don't get included. The NZ Seismological Observatory sends preliminary locations of larger events to NEIC every two weeks. This means the NZ locations won't show up in the daily listings and maybe not the weekly but they should be in the monthly listings. Cheers, John Taber School of Earth Sciences Victoria University of Wellington New Zealand _____________________________________________________________________ Public Seismic Network Mailing List (PSN-L) From: "Rex Klopfenstein, Jr." Subject: VBB Leaf Spring Mount Question Date: Tue, 13 Oct 1998 19:49:16 -0400 Sean: I am looking at your "Hinge and Leaf Spring Mounting Detail" (large scale). I have a small question on the alignment of the spring attachment. I understand the overall concept, my question has to do with the orientation of the leaf spring flexures with the 3/16" square tube. It appears that your drawing shows the sq tube rotated slightly to accommodate the curvature of the spring; that is, the flexure does not form a 90 degree angle with the face of the square tube. Looking at the photographs, I can't make out the actual detail of the flexure/tube alignment. Thanks in advance Rex Klopfenstein, Jr Bowling Green, OH _____________________________________________________________________ Public Seismic Network Mailing List (PSN-L) From: S-T Morrissey Subject: Re: Geophone amps Date: Tue, 13 Oct 1998 19:29:05 -0500 (CDT) Rick. Here is the info I previously posted about the amplifier: Re. micropower seismic amplifier: (Oct12rev). Since 1981 we have been using a micropower seismic amplifier for all the telemetry stations. It is based on the LM4250CN micropower amplifier. It uses four amplifiers, with the total current drain of 80 microamps at +-4.05 volts. The first two amps are for DC gains of 18 to 54 db and 6 to 36 db. The second two amps are a 4-pole low pass filter at 20 hz. The first and second gain stages are AC coupled at a 60-second corner to remove the DC offset, and the output is similarly AC coupled for input to the VCO. The noise referred to the input at 60db (gain of 1000) is 1 microvolt. For most stations using the L4-C seismometer (pre-scaled for 100v/m/s output) the gains range from 60 to 72 db. The additional gain available up to 90 db (gain of 31 600) is useful for smaller geophones. The schematic is posted on the PSN info page at: http://www.eas.slu.edu/People/STMorrissey/index.html The original is an old pencil drawing, so the quality is not very good. If you want to send a SASE with 4 or 5 stamps, I can mail a copy, along with the circuit board artwork. I will try to post a photo of the board. I have also started a CAD redrawing of it.... (Unfortunately I don't have time to get into the hardware business, like getting the board reprinted for sale. And I expect that we would need an interest in 50 assembled boards to be able to have Sprengnether make them and sell them, for which they would probably charge $100 per. I will ask them about it.) For use as an isolated amplifier, (installed in the borehole near the seismometer or geophone), photo-lithium batteries can be used. A battery pack of 6 of the the AA size, configured for +,- 4.8 volts, will provide 80 microamps for 30 months or more. The AA size costs about $6 per pair. Larger lithiums will last for years, or the shelf life: 80 microamps is about the level of the internal leakage. Motorola makes a pin-compatible micro-power amp, the MC1776, available from Newark. The main caveat for using these micro- powered (we run them at 20 microamps) amps is that soldering them into a circuit board usually will make them very noisy, so sockets are always used. In fact, we test the amplifiers for noise, and use the quietest as the first amplifier. We will go through a tube of 50 amps, and maybe 10 will have about 1/10th the noise of the rest, and maybe another 10 will be 10x noisier than the mean, and get used in the milliwatt DC-DC converter instead of the seismic amp. The other important detail for electronics buried in a sealed container with the seis or geophone is that it must be kept VERY dry, which requires fresh active desiccant AND a Humidity indicator. We use the paper-strip type with graduations of 10% steps. In the "mug shot" on my web home page you can see a container of fresh desiccant near my right knee, and the ABS "pipe vault" covers the hook on my left arm. The cap of the "pipe vault" is attached with a 3" hubless clamp, which is never reused in the remote sites that are opened only every other year. The complete telemetry system is in the aluminum container that is about the size of a "Pringles" can. Regards, Sean-Thomas _____________________________________________________________________ Public Seismic Network Mailing List (PSN-L) From: Greg Subject: Re: Geophone amps Date: Wed, 14 Oct 1998 00:50:59 +0000 S-T Morrissey wrote: > (Unfortunately I don't have time to get into the hardware > business, like getting the board reprinted for sale. And I > expect that we would need an interest in 50 assembled boards to > be able to have Sprengnether make them and sell them, for which > they would probably charge $100 per. I will ask them about it.) I emailed Sprengnether on Sunday. No response yet. Maybe if a couple of people hit them at once, it might peak their interest a bit more. I may end up using Larry's amp yet. If these things can't be had easily for a reasonable price. I might try asking if someone would build one for a reasonable fee, based on the schematic on Sean-Thomas's web site. The parts look pretty cheap, but if only 1 in 50 amps is good enough to use... ,Greg _____________________________________________________________________ Public Seismic Network Mailing List (PSN-L) From: S-T Morrissey Subject: Re: VBB Leaf Spring Mount Question Date: Tue, 13 Oct 1998 19:55:43 -0500 (CDT) Rex, The drawing is not perfect. The square tube is orthogonal with the end of the spring, and the flexures are at right angles to it. But this puts the flexure at an angle from the vertical, since the ends of the spring will be to the left of the fixed rod at the upper end, and to the right of the fixed rod at the lower end (here again, the drawing detail is wrong: the lower end is too long and low). The approximate alignment of the flexures is along a line drawn between the centerlines of the two fixed rods. But since the fixed rods are free to rotate when the spring is installed, they will align themselves. I usually "twang" the spring a few times after installation so it will find its most relaxed position. I'm taking notes for updating the drawing. I need to do an overhead view to clarify many details. Regards, Sean-Thomas _____________________________________________________________________ Public Seismic Network Mailing List (PSN-L) From: S-T Morrissey Subject: Re: Geophone amps Date: Tue, 13 Oct 1998 20:06:56 -0500 (CDT) Greg, I need to clarify the selection of amplifiers for noise: they are all good enough to use, but when the chance to push the envelope gets into the hands of a perfectionist, why not quickly screen them? The main point was that soldering them in to the PC board usually makes them noisier. Regards, Sean-Thomas _____________________________________________________________________ Public Seismic Network Mailing List (PSN-L) From: lahr@.................. Subject: NEIS Catalog Date: Thu, 15 Oct 1998 10:56:29 -0600 (MDT) I checked with Waverly Person about the event of April 21, 1998 at 39.02S 174.92E that was not included in any catalogs. The problem was human error -- it happens some times. This event will be included in the monthly listing for April 1998. I'm not sure why the other five mb 5+ events were not published, although their actual magnitudes could be much smaller. It could be due to very poor solution quality. Waverly told me that mb magnitudes are systematically too large if computed for regional distances (anything less than about 16 degrees). This may account for the difference between the Wellington mb's and the final magnitude determined by NEIS. Also ML magnitudes are not used if the depth is greater than 33 km (except for Alaska, where the depth can be as great as 70 km). Coda magnitudes are another option and are not limited by depth. Dave Nelson, if you see this happen again, let me know right away while the event is still in the system and there are printouts with notes to look at. I'll see if I can find out what is happening. Cheers, JCLahr _____________________________________________________________________ Public Seismic Network Mailing List (PSN-L) From: "Rex Klopfenstein, Jr." Subject: VBB Transfer Function References Date: Thu, 15 Oct 1998 21:23:30 -0400 Sean I have been reading your draft of "A High Resolution Broadband Vertical Seismometer Constructed from Hardware Store and Consumer Electronics Components" list on your page. Prior to the section describing the "The Transfer Function", a reference is made to two articles (thesis?). One is by J.M. Stein and the other by Wielandt and Steim. Could you provide a complete reference to these two articles? Thanks Rex Klopfenstein, Jr Bowling Green, OH _____________________________________________________________________ Public Seismic Network Mailing List (PSN-L) From: Edward Cranswick Subject: Re: SVJrH Gilroy Seismic/Weather Station Date: Thu, 15 Oct 1998 20:56:08 -0600 Jan & Ted- Have either of you heard from AGU about your December poster presentation with the school? I have been distracted by various things such as the Pymatuning EQ , but I think we should start checking with AGU about getting passes for a bunch of the students. Please let me know about what the status is. -Edward Jan Froom wrote: > Larry - Steve.... I've decided to put my commercial vertical & horizontal > devices over at SVJH along with Dick's shoe box horizontal & maybe one of my > home brew horizontals too. After all, it a School of Science & Technology ! > Let's give them some Technology along with the science....... > > What I need to know from Larry is.... What all will I need to setup something > like you and Steve are suggesting ? Do I need to buy one of your (Larry's) > cards ? Or can I keep using EMON ? What size PC ? How will it get linked > into the Weather Internet Server ? How will the kids interface to it. ? Are > you going to come down to help me set it up.... maybe I should say, are you > going to come down so I can watch you set it up ? I think I can spring for > Dinner and your gas ! > > Also wondering if you've tried the WWVB RS232 Clock (like the Radio Shack one > except with a RS232 interface), I have and it's duck soup to use.... > > We ordered the Weather Station last week..... and while I know you two boo & > hiss the fact that it comes with WINDOWS 98 you have to remember we're not as > sharp as you two... And I'm trying to spare Larry the trips from Redwood City > to Gilroy. The school has practically given me a whole room to set up the > Seismic & Weather Station in and it's all wired for the internet. > > I appreciate all of your help and enthusiasm and am really excited about > getting this set up going at SVJH! > > Jan > "Credo Quia Absurdum" > I Believe Because It Is Absurd -- Edward Cranswick Tel: 303-273-8609 US Geological Survey, MS 966 Fax: 303-273-8600 PO Box 25046, Federal Center cranswick@........ Denver, CO 80225-0046 USA E.M. Forster said, "Only connect". _____________________________________________________________________ Public Seismic Network Mailing List (PSN-L) From: Edward Cranswick Subject: Re: Maximumius Glutomious Alligator bites Date: Thu, 15 Oct 1998 21:41:52 -0600 Meredith- Sorry about the delay in responding to your question about what happened during the Pymatuning EQ aftershock investigation, but here are some email bytes: In the middle of Sept, I spent a couple of weeks in a kind of spiritual retreat, including 8 days of solitary existence in the mountains inhabiting a circle 108' in diameter during which I fasted for 5 days ... the day after I returned to my apartment in Golden, 25 Sep, there was a magnitude 5.2 earthquake in Pennsylvania (eastern US), and I spent the next week in a motel room at the epicentral area, surrounded by computers in my motel room, swigging coffee and chomping chocolate bars 18-20 hrs/day, with TV stations arriving in droves to interview us, including a helicopter with the camera crew that landed in the field behind the motel -- it was like James Bond ... I was waiting for Pussy Galore to jump out. Check out: ; we put this website together in the field during the aftershock investigation which, as far as I know, is a first (also, there were no aftershocks, which is also a first; so we had a virtual aftershock study .... I'll forward the email about my virtual love affair). Subject: Re: The Show Date: Fri, 09 Oct 1998 21:31:27 -0600 From: Edward Cranswick Organization: US Geological Survey, Golden, CO To: Debi Kilb CC: Ann Metzger , Joan Gomberg , john armbruster , Jon Cox , Katherine Stanley , Kaye Shedlock , leonardo seeber , "Mark E. Meremonte" , "Mitchell M. Withers" , Stephen Horton , bodin@........................ References: 1 Debi- The show went well. I hung the bra just to right of the projector screen but didn't mention it until the very end of the talk, sort of as an afterthought (despite your recomendation, I decided not to model it with my USGS hat and sweatshirt during the presentation). I explained how I found it hanging on the outside of my motel room door and that you denied any knowledge of it. I advanced my theory that, after collapsing in semi-coma sometime after 3:30 AM from too much nerding-out in my motel-room computer center, I had been abducted by Space Alieness's in flying saucers and forced to commit unspeakable sexual acts (I considered consulting a hypnotherapist to have these repressed X-rated memories restored). I also, for the sake of "scientific and empirical" completeness reported John & Nano's alleged story that they had discovered the bra under the bed in their room and had hung it on my door in honor of my advanced seismological studies at Lamont -- the only award I have so far received from that institution for the 4 years I trudged towards an infinitely distant Ph.D. Other than on matters regarding this vital issue, Kaye and John did most of the talking (see revised talk promo below), and I did most of the gesticulating. I think the point was well made that the Web can and should be used to dynamically interact with the public during a mainshock/aftershock sequence. As I remarked at a meeting today about our seismic hazard investigations in Seattle, many PIs have a very "static" view of their research and their audience (whoever they think that is: it is not clear) -- it is as if they don't really believe that there will be an earthquake there ... if so, why are we being funded? I did make some other remarks about the increasing virtuality of it all, particularly of reality, but I did not advance the idea of a website, the Pymatuning one or others in general, as being a dynamic document that automatically gives credit to all concerned. ... and then this morning there was the aftershock, and so the show goes on ... -Edward Debi Kilb wrote: > Edward, > > So ... how did it go yesterday? > > Cheers, > Debi > Subject: > ENTRY LEVEL CONFERENCE ROOM: PYMATUNING EATHQUAKE TALK ***TODAY***] > Date: > Thu, 08 Oct 1998 11:56:59 -0600 > From: > Edward Cranswick > Organization: > US Geological Survey, Golden, CO > To: > geo_haz_gld@.................. > > > > > Because of the continuing absence of aftershocks, we are trying to keep > things rolling by moving the talk to the > > ENTRY LEVEL CONFERENCE (LUNCH) ROOM > (ANOTHER change of venue) > Thursday, 8 Oct 1998, 2:00 PM > > (actually the people -- Susan Rhea, Pam Detra, and Lynn Highland -- > putting the booth together for USGS GeoHazards at GSA kindly allowed us > to interrupt their schedule for an hour; thank you) > > -- > Edward Cranswick Tel: 303-273-8609 > US Geological Survey, MS 966 Fax: 303-273-8600 > PO Box 25046, Federal Center cranswick@........ > Denver, CO 80225-0046 USA E.M. Forster said, "Only connect". > > > > Subject: > ***TODAY*** PYMATUNING EATHQUAKE TALK ***TODAY*** > Date: > Thu, 08 Oct 1998 09:30:10 -0600 > From: > Edward Cranswick > Organization: > US Geological Survey, Golden, CO > To: > geo_haz_gld@.................. > > > > Jon Cox, Kaye Shedlock, Mark Meremonte (special guest appearance) and > Edward Cranswick will present a summary of the Pymatuning Earthquake. > Kaye will present the material about the mainshock and tectonic > background that she prepared for briefings. Mark will present himself. > Jon and Edward will focus on the virtual aspect on of the event, > including the field investigation and website: > > > THE 1998 SEP 25 PYMATUNING EARTHQUAKE AND ITS VIRTUAL AFTERSHOCK > SEQUENCE > > Thursday, 8 Oct 1998, 2:00 PM > (change of venue) > 4th Floor Conference Room > > -- > Edward Cranswick Tel: 303-273-8609 > US Geological Survey, MS 966 Fax: 303-273-8600 > PO Box 25046, Federal Center cranswick@........ > Denver, CO 80225-0046 USA E.M. Forster said, "Only connect". > -- Edward Cranswick Tel: 303-273-8609 US Geological Survey, MS 966 Fax: 303-273-8600 PO Box 25046, Federal Center cranswick@........ Denver, CO 80225-0046 USA E.M. Forster said, "Only connect". meredith lamb wrote: > Edward Cranswick, > > Uhhh.....is there any cure out there in Ohio, for your bites? > The weather back here in Colorado was only in the 50's today, > and perhaps upon your return, the cool, will sooth the ruffles? > Ha. > > Don't hear anything of aftershocks. Afterbites? Ha. > > Presume they send you off anywhere for these mainland quakes. > Any interesting or noteworthy history stories to pass on of your > experiences? Imagine some of the storys maybe quite interesting. > Do you take gobs of equipment? Government plane? > > Thanks, > > Meredith Lamb > > _____________________________________________________________________ > > Public Seismic Network Mailing List (PSN-L) > > To leave this list email listserver@............. with the body of the > message: leave PSN-L -- Edward Cranswick Tel: 303-273-8609 US Geological Survey, MS 966 Fax: 303-273-8600 PO Box 25046, Federal Center cranswick@........ Denver, CO 80225-0046 USA E.M. Forster said, "Only connect". _____________________________________________________________________ Public Seismic Network Mailing List (PSN-L) From: Edward Cranswick Subject: Re: Phantom Postings Date: Thu, 15 Oct 1998 22:09:16 -0600 Bob- I have been meaning to reply to your message, which arrived during the height of my email difficulties, for months, but I have procrastinated as usual. With respect to Mono Lake, the first Californian and, hence, "real" earthquake I chased was the 25 May 1980 Mammoth Lakes sequence that consisted of 3 M6+ events that Sunday and the largest, a M6.4 which I felt in the town of Mammoth and which is still the largest earthquake I have experienced (most seismologists are to earthquakes like Catholic priests are to sex -- the authorities on the subject though they have never experienced it), the following Tuesday. All the skiers had vacated the town of Mammoth on Sunday night and been replaced by seismologists on Monday morning. I am conjecturing from your name that you are of Armenian descent ... and that is another story of earthquakes which, though they have wreaked havoc in Armenia, constititute only a part of the past and recent drama of the Armenian people. So what were you doing in Mono Lake with Lou Pakiser? I saw him two months ago, in August 1998, at the retirement party for my ex-father-in-law, Jack Evernden, but since I was quite distracted at the time by the presence there of my Russian ex-wife and ex-stepdaughter and their new husband/stepfather, I did not think of mentioning your email to Lou. -Edward Robert Avakian wrote: > I, too am seeing the same thing, I write and don't see it. However, I > thought my posts were simply being edited out by the moderator. Now I > wonder. You seem to be coming in loud and clear. > > It almost looks like the software omitts the originating address when it > sends the meassage out to the list. > > Did you see my post about Mono LAke in conjunction with the Owens lake > rewatering post? I figured they edited it out as tooo far afield. > > I was at the lake in 1970 with Lou Parkeser(sp?) from Menlo Park and > about five USGS trucks for a weekend of seiemic work. There were still > a number of bird carasses on shore from some water charges they had set > a year or two before. At 5:30 AM, we totally overloaded Lee Vining's > resources, especaily the cafe. > > Take care > > Bob Avakian -- Edward Cranswick Tel: 303-273-8609 US Geological Survey, MS 966 Fax: 303-273-8600 PO Box 25046, Federal Center cranswick@........ Denver, CO 80225-0046 USA E.M. Forster said, "Only connect". _____________________________________________________________________ Public Seismic Network Mailing List (PSN-L) From: Greg Subject: Re: Geophone amps Date: Fri, 16 Oct 1998 04:55:19 +0000 S-T Morrissey wrote: > > Greg, > I need to clarify the selection of amplifiers for noise: they > are all good enough to use, but when the chance to push the Good, that'll mean that mine will be slightly cheaper. 4 x $2.50 amps is one thing, but more than 50 is absurd for the benefits to me. > The main point was that soldering them in to the PC board usually > makes them noisier. A lot of these messages get kept in my "PSN-archive folder" because of useful little bits like that. I got a response from Sprengnether today. They sent a simple fax, that looks like it came out of a brochure. It's a little difficult to read, but there is a picture and some text about one amp. The model number is AS-110. It looks like it goes into some kind of rack mounting and not in the hole with the instrument. It has three dials for setting the gain (in 6 dB steps from 60 to 120), high cutoff frequency (5, 10, 30, and 100 Hz), and low cutoff (.2, 5 and 10 Hz). The card requires +- 15 VDC and uses 6mA (from what I read). The output is up to +- 10 V. It says PC-card configuration, but that's not PCMCIA in the picture. No price although I did ask for one, which makes me worry a bit. Still plenty of shopping days before the holiday season ;) Buy yourselves something super nice. I am. ;) ,Greg _____________________________________________________________________ Public Seismic Network Mailing List (PSN-L) From: Joe Irvine Subject: Fwd: SOHO IS NEARLY BACK IN BUSINESS Date: Thu, 15 Oct 1998 22:54:41 -0700 >Date: Wed, 14 Oct 1998 17:10:25 -0400 (EDT) >From: NASANews@........... >Subject: SOHO IS NEARLY BACK IN BUSINESS >Sender: owner-press-release@................. >To: undisclosed-recipients:; > >Don Savage >Headquarters, Washington, DC October 14, 1998 >(Phone: 202/358-1727) > >Bill Steigerwald >Goddard Space Flight Center, Greenbelt, MD >(Phone: 301/286-5017) > >Simon Vermeer >European Space Agency Headquarters, Paris, France >(Phone: 33-1-5369-7155) > >RELEASE: 98-190 > > >SOHO IS NEARLY BACK IN BUSINESS > > High-quality new pictures of the Sun, taken earlier this >week from the Solar and Heliospheric Observatory (SOHO), have >raised hopes that the mission may soon be returned to scientific >operations. Engineers have successfully reactivated nine of the >12 instruments on the European Space Agency (ESA)/NASA SOHO >mission, which has been out of commission for nearly four months >after contact was lost on June 24. > > Images from the Michelson Doppler Imager and the Extreme >Ultraviolet Imaging Telescope on SOHO are posted on the Internet >at: http://sohowww.nascom.nasa.gov > > "Scientists on both sides of the Atlantic have waited >anxiously for the recovery of SOHO," commented Roger Bonnet, ESA's >director of science. "Thanks to the extraordinary determination >and skill of ESA and NASA personnel, with industrial contractors >and scientific teams also playing their part, the world has >recovered its chief watchdog on the Sun. SOHO is needed more than >ever, because the Sun is rapidly becoming stormier with a mounting >count of sunspots." > > "It's very exciting to see these images again after so >many weeks of concern. We hope that all the SOHO scientific >instruments can be returned to the same level of health, so we can >resume normal scientific operations in the near future," said Dr. >Joseph Gurman, the U.S. project scientist for SOHO, and co- >investigator on the Extreme Ultraviolet Imaging Telescope (EIT). > > "As of today, nine of the 12 instruments on board SOHO >have been turned on. Four of them are already fully functional; >the other five are still undergoing careful recommissioning >activities. But so far no signs of damage due to thermal stress >during the deep freeze have been detected. I tip my hat to the >engineers who built this spacecraft and these sensitive but robust >instruments," said Dr. Bernhard Fleck, the ESA project scientist >for SOHO. The remaining three instruments will be switched on >over the next few weeks.. > > The images are the latest success for the team during a >complex, challenging recovery sequence. On July 23, SOHO was >located using radar techniques with the 305-meter Arecibo, Puerto >Rico, radio telescope of the U.S. National Astronomy and >Ionosphere Center as a transmitter and a 70-meter dish of the NASA >Deep Space Network as a receiver. SOHO first responded to radio >transmissions on August 3, and telemetry from SOHO was received >August 8, telling controllers the condition of the spacecraft and >its instruments. The spacecraft's frozen hydrazine fuel was >gradually thawed, and on September 16, SOHO's thrusters were fired >to stop its spin and to place it in the correct orientation >towards the Sun. > > Prior to the interruption, instruments on SOHO had taken >about two million images of the Sun, an activity representing over >a terabyte (a trillion bytes) of data. After its launch on Dec. >2, 1995, SOHO revolutionized solar science by its special ability >to observe simultaneously the interior and atmosphere of the Sun, >and particles in the solar wind and the Sun's outer atmosphere. > > SOHO observations have been the subject of more than 200 >papers submitted to refereed, scientific journals. Apart from >discoveries about flows of gas inside the Sun, giant "tornadoes" >of hot, electrically charged gas, and clashing magnetic field- >lines, SOHO also proved its worth as the chief watchdog for the >Sun, giving early warning of eruptions that could affect the >Earth. > > SOHO operates at a special vantage point 1.5 million >kilometers (about one million miles) out in space, on the sunward >side of the Earth. The spacecraft was built in Europe and it >carries both European and American instruments, with international >science teams. SOHO was launched on an Atlas IIAS rocket and is >operated from NASA's Goddard Space Flight Center in Greenbelt, >Maryland. > > In April 1998, SOHO's scientists celebrated two years of >successful operations and the decision of ESA and NASA to extend >the mission to 2003. The extension enables SOHO to observe >intense solar activity, expected when the count of sunspots rises >to a maximum around the year 2000. > > - end - > >The first EIT image taken in the Fe IX/X line at 171 A is >available at: > >http://sohowww.estec.esa.nl/operations/Recovery/eit_171_981013.gif > and > >http://sohowww.nascom.nasa.gov/operations/Recovery/eit_171_981013. >gif > >The MDI image can be found at: > http://soi.stanford.edu > >The latest SOHO EIT images can be found on the Web at: > http://umbra.nascom.nasa.gov/eit/eit_full_res.html > >Details about the operations and about SOHO in general, can be >found at: > http://sohowww.estec.esa.nl > and > http://sohowww.nascom.nasa.gov > >Information on the recovery of SOHO can be found at: >http://sohowww.nascom.nasa.gov/operations/Recovery//operations/Rec >overy/ > > * * * > >NASA press releases and other information are available automatically >by sending an Internet electronic mail message to domo@............ >In the body of the message (not the subject line) users should type >the words "subscribe press-release" (no quotes). The system will >reply with a confirmation via E-mail of each subscription. A second >automatic message will include additional information on the service. >NASA releases also are available via CompuServe using the command >GO NASA. To unsubscribe from this mailing list, address an E-mail >message to domo@............ leave the subject blank, and type only >"unsubscribe press-release" (no quotes) in the body of the message. > _____________________________________________________________________ Public Seismic Network Mailing List (PSN-L) From: Edward Cranswick Subject: Re: Geophone amps Date: Thu, 15 Oct 1998 23:58:19 -0600 Greg- What is Sprengnether's website URL? -Edward Greg wrote: > ... > I got a response from Sprengnether today. ... -- Edward Cranswick Tel: 303-273-8609 US Geological Survey, MS 966 Fax: 303-273-8600 PO Box 25046, Federal Center cranswick@........ Denver, CO 80225-0046 USA E.M. Forster said, "Only connect". _____________________________________________________________________ Public Seismic Network Mailing List (PSN-L) From: "Al Allworth" Subject: Suggestion for seismo base Date: Thu, 15 Oct 1998 23:16:09 -0700 Earlier this year there was a lot of discussion about suitable material for a stable pier for a seismometer mounting. About the same time I bought a granite surface plate but never thought at that time of using one for a pier surface. Granite is very stable and the prices of surface plates has really taken a dive with China now as a supplier. The one I bought was around $90.00. It is 18" x 24" x 3" and weighs 145 lbs. They also have one 12" x 18" x 3" at $30.00 and one 9" x 12" x 3" for $20.00. The surface accuracy is around 0.0001". The company I bought from is Industrial Pipe and Steel in El Monte, Calif. http://ipstool.com I think any machine shop supply company would have them. The American made ones sell for nearly 10 times these prices. Just a thought for those building piers. Al Allworth _____________________________________________________________________ Public Seismic Network Mailing List (PSN-L) From: Karl Cunningham Subject: Re: Suggestion for seismo base Date: Fri, 16 Oct 1998 09:02:54 -0700 Al -- Your comments brought back an old memory: Companies that cut granite slabs for surface plates (and other things) sometimes have discards that they cannot use because of inclusions, cracks, etc. I saw one used by an amateur laser experimenter that was about 3' by 6' by 4" thick, weighed about 1000#, and it cost him about $100. The surface wasn't mirror smooth, but as good as a concrete floor. He was trying to isolate his apparatus from earth noise and thus supported the plate with inflated inner tubes. Presumably, setting such a plate in grout could do the opposite. Karl Cunningham La Mesa, CA. PSN station #40 karlc@....... At 11:16 PM 10/15/98 -0700, you wrote: > >Earlier this year there was a lot of discussion about suitable material for >a stable pier >for a seismometer mounting. About the same time I bought a granite surface >plate but never thought at that time of using one for a pier surface. >Granite is very stable and the prices of surface plates has really taken a >dive with China now as a supplier. The one I bought was around >$90.00. It is 18" x 24" x 3" and weighs 145 lbs. They also have one 12" x >18" x 3" at $30.00 and one 9" x 12" x 3" for $20.00. The surface accuracy >is around 0.0001". The company I bought from is Industrial Pipe and Steel in >El Monte, Calif. http://ipstool.com _____________________________________________________________________ Public Seismic Network Mailing List (PSN-L) From: Greg Subject: Re: Geophone amps Date: Fri, 16 Oct 1998 17:32:08 +0000 Edward Cranswick wrote: > > Greg- > What is Sprengnether's website URL? http://www.sprengnether.com/ I didn't see that amp on their website though. A lot of their "product information" is a request more information form. I hate that. They had time to make the form, but not to type in the product information? As long as I'm looking through the bookmarks: This is the first amateur instrument I ever found. I was very happy to find the PSN site. http://met.univnorthco.edu/resource/seismo.htm ,Greg _____________________________________________________________________ Public Seismic Network Mailing List (PSN-L) From: S-T Morrissey Subject: Re: VBB Transfer Function References Date: Fri, 16 Oct 1998 18:00:27 -0500 (CDT) Rex, The references you seek are: Steim, J.M., "The Very-Broadband Seismograph"; Doctoral Thesis, Harvard University, Cambridge, Massachusetts, 1986. (161 pages) Steim, J.M., and E. Wielandt, "Report of the Very Broad Band Seismograph", Harvard University, Cambridge, Massachusetts, February, 1985. (unpublished progress report). Wielandt,E and G. Streckeisen, "The Leaf-Spring Seismometer: Design and Performance", Bull. Seism. Soc. Am., 72, 2349-2367, December 1982 Also of interest is: Usher, M.J, Guralp,C, Burch, R.F., "The design of miniature wideband seismometers" Geophys. J.R. Astro. Soc., 55, 605-613; 1978 RE: Amplifier/Demodulator schematic: Also, on another subject, I have been investigating a problem with excessive noise from the VRDT of the VBB seis when I open up the bandwidth, for high frequency response. I have found that the amplifier/demodulator schematic has several errors with respect to the connections of the MC14066 demodulator, causing jitter in the demodulated carrier. I believe I have solved this noise problem, reducing the noise to less than the equilavlent displacement of 1 nanometer, (less than 5 millivolts peak-peak, DC to 100 hz, at the x40 VBB output with a VRDT sensitivity of 5000mv/micron) This noise was not a problem for the tiltmeters, which were heavily filtered at 20 seconds. I will post a revised schematic next week. regards, Sean-Thomas _____________________________________________________________________ Public Seismic Network Mailing List (PSN-L) From: S-T Morrissey Subject: preamplifier images Date: Fri, 16 Oct 1998 19:25:44 -0500 (CDT) Re: Seismic preamplifier images: I have scanned the actual circuit boards of the micropower seismic preamplifier along with the foil side of the PC board. I also included an image of a perforated board assembly of the same amplifier, and placed them on the ... PSN INFO ... page at: http://www.eas.slu.edu/People/STMorrissey/index.html The jpeg image is 78k. I am surprised that the HP scanner can produce a useful image of a shallow object; the depth of field is about 1 cm. It sure beats trying to photograph it and then scan it. I should try this more often with circuit boards. Any suggestions? regards, Sean-Thomas _____________________________________________________________________ Public Seismic Network Mailing List (PSN-L) From: meredith lamb Subject: Re: preamplifier images; the scanning of Date: Fri, 16 Oct 1998 21:16:50 -0600 S-T Morrissey wrote: > Re: Seismic preamplifier images: > > I have scanned the actual circuit boards of the micropower seismic > preamplifier along with the foil side of the PC board. I also included > an image of a perforated board assembly of the same amplifier, and > placed them on the ... PSN INFO ... page at: > http://www.eas.slu.edu/People/STMorrissey/index.html > The jpeg image is 78k. > > I am surprised that the HP scanner can produce a useful image of > a shallow object; the depth of field is about 1 cm. It sure beats > trying to photograph it and then scan it. I should try this more > often with circuit boards. Any suggestions? > > regards, > Sean-Thomas > Sean, I tried the same routine with my HP Scanjet 6200/6250c and also got the general same results. For bright copper patterns, however, it turned out black, and the color of the circuit board was the same tan color of the actual board. Think you may have used some other model of HP scanner where the copper turns out a same copper color. Another trial of a board with limited parts came out pretty good also. Here the color of the copper leaded circuit leads (gray), did not show up very well, compared to the bright copper of the circuit above. As is, any circuit layout could be displayed reasonably well, and could be a nice guide to wiring. Perhaps if one used white wires on the underside of a commercially available board like the Radio Shack 276-170, $2.99 or similar, it might work out OK, for web site display. That board doesn't have a ground plane though. This board has bright copper leads. Of course there is a world of general purpose add on circuit boards, but the cost can skyrocket over the span. Basically, I'am only suggesting use of a commercial board and white wires for visual contrast, of your preamp, for web display. That way the cost comes way down, but the home adoptee has to do alittle effort to save money. Thanks, Meredith Lamb _____________________________________________________________________ Public Seismic Network Mailing List (PSN-L) From: Brett Nordgren Subject: Vertical barometer fix Date: Sun, 18 Oct 1998 14:03:09 -0400 Hello all, I've been following the seismo activities of my neighbor Bob Barns, and he pointed me here to the PSN list. The vertical instruments have always interested me, though until Sean-Thomas designed his beautifully simple device, I hadn't thought it would be practical to build one. One fundamental difficulty with verticals, is that they record barometric changes along with everything else, "floating" and "sinking" as the air density varies. I had an idea for a possible solution that involves adding a float to compensate the barometric effect. If you add a secondary boom attached to the main boom, going in the opposite direction, across the main hinge, and then you attach a sealed float to that boom at the proper distance from the hinge, the barometric effects on the float should be able to approximately balance the effects on the main system. A plain glass Christmas tree ball, with its opening flame-sealed should make a handsome float. Very rough calculations on the STM-8 indicate that a 3" ball on the end of a 3.5" boom should be about right. The secondary boom system could be quite light; it only needs to be stiff enough to have no mechanical resonances lower than those of the main boom. The secondary boom length would have to be adjustable to permit exact calibration. In fact, calibration may not be so easy unless you have access to a pressure/vacuum chamber. Possibly, careful calculation could get it close enough. If anyone with a vertical is interested (read: foolish enough) to want to try this, I'd be happy to go through the numbers, and would be very interested to hear how well/if it works. Brett Nordgren _____________________________________________________________________ Public Seismic Network Mailing List (PSN-L) From: S-T Morrissey Subject: barometric floats Date: Sun, 18 Oct 1998 19:39:17 -0500 (CDT) Brett, It seems that good ideas come around again and again, and someday someone will make them work. Regarding your ideas re pressure noise: I have been experimenting with the barometric floatation compensation for some time on the STM-8, with rather mixed results. Some excerpts from previous notes: (last April) Re the seis barometric compensation with sealed pill jars installed on the back side of the hinges: again, an experiment with an indefinite result. It seemed to help, but not notably; I suspect that they were actually flexing (plastic caps) with small changes of pressure. And figuring the correct volume*moment wrt. the boom and the seis mass was an ambiguous endeavor. I have thought of trying a copper toilet tank float if a real lightweight could be found. Or even some very low density but impervious solid. (last July) Re the pill jar (plastic) barometric flotation compensation: as I mentioned, figuring out the volume*distance of all the mass + boom + coils + etc. is nearly impossible. And trial + error methods cannot approximate the complex integration. And I believe that other pressure-induced noise sources play a major role, like the breathing of the coil-magnet assembly with pressure change. I'm only seeing 10 to 20 mv of noise, which amounts to about 12 to 24 nanometers of displacement (with 400 mv/micron and 2x gain in the line driver output). I also think that wherever the "sealed" wooden shelf board box breathes, it makes minute jets of air that blow the mass around. If I observe the high-gain output of the microbarometer, I don't see a consistently repeatable correlation with the noise. So the "counter-flotation" scheme may have some benefit, but is not a solution. (today:) At the suggestion of ?? (I lost the reference), I substituted glass xmas tree balls for the pill jars, and again tried to calculate the compensation effect. A 6 cm ornament has a volume of 113cm^3. I figured the seismometer mass volume (53cm^3) times the distance from the hinge (3.76cm) as a moment*volume of 2019cm^3*cm. I used two ornaments, epoxied together at the necks with a 5mm length of small brass tube; they have to be 8.9 cm from the hinge. THis is about the same volume that you estimated (your 3" ornament is 231.6cm^3?). This seemed to help for long term barometric change, which was evident when I manually logged the pressure and position, as well as temperature, at hourly intervals or so for 5 days. But the short term noise, of the order of 60 to 100 seconds, was little changed. So I believe that "breathing" of the box, the coil-magnet assembly, etc., are blowing the boom around. Once I get the seis into the contaiment (a terrarium) I can lightly pressureize it (by blowing on a tube) to get better info on pressure correction. But the problem with any enclosure or contaiment is that it MUST be absolutely airtight, since the slightest leak will cause an air jet that will blow the mass, the boom, etc., (and the ornaments) around, which usually causes asymetrical bumps when the pressure increases, which is what I see in the data. Today was windy here, and whenever the wind blew the storm doors open (they are not latched, since my dogs use them), the data would take a positive excursion. But air exiting a from a small hole will be less of a jet inside the box. Except that an air pressure drop will blow the coil up out of the magnet gap, ventilate the coils of the VRDT, make the zeroing gearmotor case wheese, and every tapped hole with a screw in it will vent. Not to mention what the enclosure/pier interface is doing to the base of the seismometer (my enclosure floats on foam strips, and the seis feet go through holes in the bottom, closed with foam collars, and rest directly on the pier tiles). Regards, Sean-Thomas _____________________________________________________________________ Public Seismic Network Mailing List (PSN-L) From: Brett Nordgren Subject: Re:Barometric floats and flat springs Date: Sun, 18 Oct 1998 22:15:21 -0400 Sean-Thomas, Much appreciate your calling my float suggestion "a good idea coming around again" rather than "stale common knowledge". Must have missed it scanning the archives. I'd wondered if that float would make a pretty good sail for the stray breezes. Sounds like it might, indeed. On another subject: I'd been working on an analysis of flat springs such as used in the STM-8 and have had some reasonable results computing the force vs length curves. Larry Cochrane kindly archived two files which document my results to date. This, too, I'm sure has been done before, but am hoping I can perhaps shed a bit more light on the problem. http://psn.quake.net/incoming/spring1.pdf deals with the math for the calculations. http://psn.quake.net/incoming/spring2.pdf contains some spreadsheet calculations and graphs for a spring similar to the STS-8 as well as some calculated vs actual data on a narrower spring as measured by Bob Barns. I'm hoping to combine these results with a future graphical analysis of the "zero-length" geometry in order to be able to somewhat predict the natural characteristics of a given setup. Regards, Brett Nordgren _____________________________________________________________________ Public Seismic Network Mailing List (PSN-L) From: Karl Cunningham Subject: Re: VBB Transfer Function References Date: Sun, 18 Oct 1998 21:32:57 -0700 At 06:00 PM 10/16/98 -0500, Sean-Thomas wrote: >The references you seek are: > >Wielandt,E and G. Streckeisen, "The Leaf-Spring Seismometer: Design and >Performance", Bull. Seism. Soc. Am., 72, 2349-2367, December 1982 Made the trip to a local university library and found the reference above. Very interesting reading! I looked for: Wielandt, E., and Steim, J. M. A digital very-broad-band seismograph. Annales Geophysicae 4b, 227-232, 1986 but they did not have that publication in that year. Is there anyone out there that has access to it and would be willing to send me a copy? I would, of course, pay for postage, expenses, and trouble. Thanks, Karl Cunningham La Mesa, CA. PSN Station #40 karlc@....... _____________________________________________________________________ Public Seismic Network Mailing List (PSN-L) From: Warner Subject: Re:Barometric floats and flat springs Date: Mon, 19 Oct 1998 04:55:17 -0700 (PDT) Brett, Nice job on the leaf spring information. Thank You! --Warner Puget Sound Country _____________________________________________________________________ Public Seismic Network Mailing List (PSN-L) From: Keith Payea Subject: Vertical barometer fix Date: Mon, 19 Oct 1998 12:56:16 -0400 For those who want to experiment with this idea, I stumbled across more goodies in the "Small Parts Inc" catalog (1-800-220-4242). They have some stainless steel floats in various shapes and sizes. A 3" spherical float costs about $20. It's good up to 500psi, and weighs 2.7 oz. Part number is A-MFX-64. = Not affiliated with them, just a satisfied customer. Cheers, Keith Keith Payea Port Hadlock Design Group phdg@.............. (425) 822-0673 _____________________________________________________________________ Public Seismic Network Mailing List (PSN-L) From: John Hernlund Subject: Re: VBB Transfer Function References Date: Mon, 19 Oct 1998 09:49:16 -0700 (MST) On Sun, 18 Oct 1998, Karl Cunningham wrote: > At 06:00 PM 10/16/98 -0500, Sean-Thomas wrote: > >The references you seek are: > >Wielandt,E and G. Streckeisen, "The Leaf-Spring Seismometer: Design and > >Performance", Bull. Seism. Soc. Am., 72, 2349-2367, December 1982 > Made the trip to a local university library and found the reference above. > Very interesting reading! > Wielandt, E., and Steim, J. M. > A digital very-broad-band seismograph. > Annales Geophysicae 4b, 227-232, 1986 > but they did not have that publication in that year. Is there anyone out > there that has access to it and would be willing to send me a copy? I > would, of course, pay for postage, expenses, and trouble. Karl, ASU library has this issue according to their catalog. Since I am interested in getting more info myself I'll go make some copies... Let me know where to send it... ****************************************************************************** John Hernlund E-mail: hernlund@....... WWW: http://www.mc.maricopa.edu/academic/phy_sci/Geology/hernlund/ http://www.public.asu.edu/~hernlund/ ****************************************************************************** _____________________________________________________________________ Public Seismic Network Mailing List (PSN-L) From: Karl Cunningham Subject: Re:Barometric floats and flat springs Date: Mon, 19 Oct 1998 10:40:57 -0700 Brett, Great work on the leaf spring analysis! Timely too, since I've been fiddling with a .031" floor scraper blade lately. I'll crank up my spreadsheet and play with some numbers. Thanks for analysis, and for posting it. Karl Cunningham La Mesa, CA. PSN station #40 karlc@....... _____________________________________________________________________ Public Seismic Network Mailing List (PSN-L) From: Doug Crice Subject: Re: Vertical barometer fix Date: Mon, 19 Oct 1998 11:45:39 -0700 I just noticed that aluminum coke cans weigh almost nothing once you take the coke out. You could punch a pinhole, drain the coke, then put a little glue over the hole. Use diet coke so there's no sugar residue. -- Doug Crice web site http://www.georadar.com GeoRadar Inc. e-mail dcrice@............ 19623 Via Escuela Drive phone 408-867-3792 Saratoga, CA 95070 USA fax 408-867-4900 _____________________________________________________________________ Public Seismic Network Mailing List (PSN-L) From: "Roger Vaught" Subject: Re: Vertical barometer fix Date: Mon, 19 Oct 1998 18:45:47 -0500 I just joined the list this afternoon. Is there an archive of messages? FAQ's? The Vertical barometer topic sounds interesting. Unfortunately, I'm in the dark as to what it is all about. Thanks, Roger - Houston -----Original Message----- From: Keith Payea To: PSN-L Mailing List Date: Monday, October 19, 1998 12:01 PM Subject: Vertical barometer fix >For those who want to experiment with this idea, I stumbled across more >goodies in the "Small Parts Inc" catalog (1-800-220-4242). SNIP _____________________________________________________________________ Public Seismic Network Mailing List (PSN-L) From: Brett Nordgren Subject: Re: Vertical barometer fix Date: Mon, 19 Oct 1998 20:34:36 -0400 Roger, I was using the term to describe a vertical seismometer that's responding more to barometric pressure changes than to ground motion. I had re-invented an idea to compensate the effect with small "float". It had been previously covered earlier this year. Try http://psn.quake.net/maillist.html#archives Brett Nordgren >The Vertical barometer topic sounds interesting. Unfortunately, I'm in the >dark as to what it is all about. > >Thanks, >Roger - Houston _____________________________________________________________________ Public Seismic Network Mailing List (PSN-L) From: barry lotz Subject: Re: VBB Transfer Function References Date: Mon, 19 Oct 1998 18:02:47 -0700 John I am interested also. Is it possible to scan it? Barry John Hernlund wrote: > On Sun, 18 Oct 1998, Karl Cunningham wrote: > > At 06:00 PM 10/16/98 -0500, Sean-Thomas wrote: > > >The references you seek are: > > >Wielandt,E and G. Streckeisen, "The Leaf-Spring Seismometer: Design and > > >Performance", Bull. Seism. Soc. Am., 72, 2349-2367, December 1982 > > Made the trip to a local university library and found the reference above. > > Very interesting reading! > > Wielandt, E., and Steim, J. M. > > A digital very-broad-band seismograph. > > Annales Geophysicae 4b, 227-232, 1986 > > but they did not have that publication in that year. Is there anyone out > > there that has access to it and would be willing to send me a copy? I > > would, of course, pay for postage, expenses, and trouble. > > Karl, > ASU library has this issue according to their catalog. Since I am > interested in getting more info myself I'll go make some copies... > > Let me know where to send it... _____________________________________________________________________ Public Seismic Network Mailing List (PSN-L) From: barry lotz Subject: Re: Barometric floats and flat springs Date: Mon, 19 Oct 1998 18:13:03 -0700 Brett I have been working with two of Sean Thomas' VBB style units for a couple of months now. It seems that the biggest variation I have found ( as Sean Thomas has mentioned in the past ) is temperature. I think that the temperature affects the stiffness of the spring by changing the length or modulus. I have yet to find data that support the fact that metal(steel) under stress may have a modulus which varies slightly with temperature. I did a rough calc and the length change appears to me second order. Regards Barry Brett Nordgren wrote: > Sean-Thomas, > > Much appreciate your calling my float suggestion "a good idea coming around > again" rather than "stale common knowledge". Must have missed it scanning > the archives. > > I'd wondered if that float would make a pretty good sail for the stray > breezes. Sounds like it might, indeed. > > On another subject: > > I'd been working on an analysis of flat springs such as used in the STM-8 > and have had some reasonable results computing the force vs length curves. > Larry Cochrane kindly archived two files which document my results to date. > This, too, I'm sure has been done before, but am hoping I can perhaps shed > a bit more light on the problem. > > http://psn.quake.net/incoming/spring1.pdf deals with the math for the > calculations. > > http://psn.quake.net/incoming/spring2.pdf contains some spreadsheet > calculations and graphs for a spring similar to the STS-8 as well as some > calculated vs actual data on a narrower spring as measured by Bob Barns. > > I'm hoping to combine these results with a future graphical analysis of the > "zero-length" geometry in order to be able to somewhat predict the natural > characteristics of a given setup. > > Regards, > Brett Nordgren _____________________________________________________________________ Public Seismic Network Mailing List (PSN-L) From: "Walt Williams" Subject: Re: VBB Transfer Function References Date: Mon, 19 Oct 1998 18:06:41 +0000 John, Count me in there also, as a 'me-to'. Thank you. Walt Williams, 98.10.19 dfheli@.............. ------- Forwarded Message Follows ------- Date: Mon, 19 Oct 1998 18:02:47 -0700 From: barry lotz To: PSN-L Mailing List Subject: Re: VBB Transfer Function References Reply-to: PSN-L Mailing List John I am interested also. Is it possible to scan it? Barry John Hernlund wrote: > On Sun, 18 Oct 1998, Karl Cunningham wrote: > > At 06:00 PM 10/16/98 -0500, Sean-Thomas wrote: > > >The references you seek are: > > >Wielandt,E and G. Streckeisen, "The Leaf-Spring Seismometer: Design and > > >Performance", Bull. Seism. Soc. Am., 72, 2349-2367, December 1982 > > Made the trip to a local university library and found the reference above. > > Very interesting reading! > > Wielandt, E., and Steim, J. M. > > A digital very-broad-band seismograph. > > Annales Geophysicae 4b, 227-232, 1986 > > but they did not have that publication in that year. Is there anyone out > > there that has access to it and would be willing to send me a copy? I > > would, of course, pay for postage, expenses, and trouble. > > Karl, > ASU library has this issue according to their catalog. Since I am > interested in getting more info myself I'll go make some copies... > > Let me know where to send it... _____________________________________________________________________ Public Seismic Network Mailing List (PSN-L) _____________________________________________________________________ Public Seismic Network Mailing List (PSN-L) From: Brett Nordgren Subject: Leaf spring analysis Date: Mon, 19 Oct 1998 21:18:58 -0400 Recently, I included this in a reply to Sean-Thomas. Have some new information to add, so will start it a thread of its own. I'd been working on an analysis of flat springs such as used in the STM-8, and have had some reasonable results computing the force vs length curves. Larry Cochrane kindly archived three files which document my results to date. This, I'm sure has been done before, but am hoping I can perhaps shed a bit more light on the problem. Although deriving the equations is a seriously hard problem, (and is mostly not included here) the results are just a matter of some easy algebra and an elliptic integral table. This is only done for springs attached by hinges at the ends. If I ever get feeling sufficiently masochistic, I might try the clamped-end analysis. ftp://psn.quake.net/incoming/spring1.pdf deals with the math for the calculations. ftp://psn.quake.net/incoming/spring2.pdf contains some spreadsheet calculations and graphs for a spring similar to the STS-8 as well as some calculated vs actual data on a narrower spring as measured by Bob Barns. ftp://psn.quake.net/incoming/Elliptic.txt is a tab-delimited text file of the first four columns of my spreadsheet data. They represent a table of elliptic integrals to import if you want to try a similar analysis on your own spreadsheet. Saves a couple of hours of typing. I'm hoping to combine these results with a future graphical analysis of the "zero-length" geometry in order to be able to somewhat predict the natural characteristics of a given setup. Note: The .pdf files can be viewed with the Adobe Acrobat Reader. If you don't already have it, it's available for most platforms by free download from: http://www.adobe.com/prodindex/acrobat/readstep.html Brett Nordgren _____________________________________________________________________ Public Seismic Network Mailing List (PSN-L) From: S-T Morrissey Subject: vbb.loop.analysis & spring Date: Mon, 19 Oct 1998 20:45:18 -0500 (CDT) Brett, The feedback world is full of notable disasters when the loop parameters hit the wall; most notable recently was the new Ariane rocket that blew up when someone programmed the loop limits on g for the smaller previous rockets. When the VBB seis has such problems, it goes momentarily ballistic, or at least wonderfully non-linear, like when a 20-ton gravel truck rumbles down the street 10 meters from the seis. This actually clips the signals at the voltage limits of the electronics, and I get a one-sided long period response at the effective period. if nothing clips, the signal is OK, which proves the hugh dynamic range of the VBB system. (Which is why filters are a no-no for it) I think that your effort to delve into the details of the feedback system will be interesting for everyone. A number of members have been looking into variations on the theme, and I am hoping that you can clarify theoretically some of the things I know only experimentally. I am rather unfamiliar with the fine nuances and mathematical realites of feedback systems, so I won't be much help. My background is physics and electronics, with all the calc and diffeq that goes with it, but I was always weak on the engineering math. But I have done some dissecting of the VBB seismometer response with MATHCAD by iterating on any and all of the parameters to see how they affect the response. Like when the first broadbands came out, all the instrument companies tried it on their current hardware, but it didn't work. I found out why: if the feedback coil resistance is at all significant (in context), the loop is unstable. I have a cabinet full of nice compact seismometers that can't be used with feedback because their coils are in the 1K ohm and up range. I assume that you have my mathcad version of the transfer function. (http://www.eas.slu.edu/People/STMorrissey/etc_export has an rtf version) You can iterate on any of the terms to fine tune them, or just put in a 100kg mass and "sink" the response. If you need the iterated versions (on r,Rp,Cp,Rf,TI,RI, etc) let me know. All they do is plot a suite of responses with, for example, Cp set from 1 to 10 uf by 1uf steps. An early article on the ideas of using feedback to make a force-balance system is "The Sensitivity and Dynamic Range of Inertial Seismographs", by Ben S, Melton; Rev. of Geophysics, vol 14, no 1, Feb. 1976. It does point out why a single force feedback loop is not successful: DC drift (thermal, tilt, etc.,) saturate the output well above the microseism or earth tidal signals of 1 micron/sec^2 that we are looking for. At that time, before good op-amps, his general conclusion was that galvanometric photo-tube amplifiers were the best way to go. But I have found that the VBB feedback is highly interactive, in the sense that one parameter or component value shows up in many terms of the response, making for interesting trade offs. And if the response of the transfer function shows an instability, the VBB seis will show it, like if Rp is infinite, the damping goes low, and the boom will actually oscillate at the effective period. And conversely, since I found no information or input about the mechanical characteristics of the spring in the transfer function, other than the mechanical period it controls, I was confident that almost any well behaved leaf spring would work if a "near" zero length (where the restoring force is nearly constant) behavior could be found without involving the rigidity if the spring, which is why I came up with the fully flexured mounting of it. By the way, the Wielandt and Streckeisen BSSA paper mentions making part of the STS-1 spring from "elinvar", as a material with a positive temperature coefficient (TC), to offset the negative TC of the rest of the spring. I'm not sure if anyone makes drywall taping knives from elinvar, though. The STS-1 still has a significant temperature problem. The bi-metallic garden thermostat coil I'm using on the STM-8 is a major improvement; I just bought some more to install in parallel, since I still haven't actually over corrected the leaf spring. Its on the list; I'm currently exploring all the nuances of the intrinsic noise of the VRDT, which is about 0.2 nanometers at 1 hz p-p. PS: If anyone didn't see the note, the schematic I posted for the demodulator has errors; I will try to get a revision up this week. Regards, Sean-Thomas _____________________________________________________________________ Public Seismic Network Mailing List (PSN-L) From: John Hernlund Subject: Re: VBB Transfer Function References Date: Mon, 19 Oct 1998 19:16:38 -0700 (MST) On Mon, 19 Oct 1998, Walt Williams wrote: > Count me in there also, as a 'me-to'. > Walt Williams, 98.10.19 > > I am interested also. Is it possible to scan it? > John Hernlund wrote: > > Karl, > > ASU library has this issue according to their catalog. Since I am > > interested in getting more info myself I'll go make some copies... > > Let me know where to send it... Alright. Sounds like a plan! Is everyone able to access it if I scan and upload it as .jpeg files on the web??? (They will have to be some what large to be legible...) Karl? Walt? Everybody else? ****************************************************************************** John Hernlund E-mail: hernlund@....... WWW: http://www.mc.maricopa.edu/academic/phy_sci/Geology/hernlund/ http://www.public.asu.edu/~hernlund/ ****************************************************************************** _____________________________________________________________________ Public Seismic Network Mailing List (PSN-L) From: Brett Nordgren Subject: Re: Barometric floats and flat springs Date: Mon, 19 Oct 1998 22:10:58 -0400 Barry, Yes, I agree that the elastic modulus of the spring probably does change with temperature. You could infer that by noting that expensive mechanical watches have balance wheel hairsprings made from a material called Elinvar, described as an alloy which has an elastic modulus that doesn't vary with temperature. I think I remember reading that the Streckeisen STS-1 vertical (and possibly others) uses a leaf spring made of Elinvar. Does anyone know who makes Elinvar or anything about its mechanical properties? It would be interesting to find out how much a small sheet would cost. Could be that, if there's enough interest, one could get together an order large enough for the manufacturer's minimums. Regards, Brett > I think that the temperature >affects the stiffness of the spring by changing the length or modulus. I have >yet to find data that support the fact that metal(steel) under stress may have >a modulus which varies slightly with temperature. I did a rough calc and the >length change appears to me second order. > >Regards > >Barry _____________________________________________________________________ Public Seismic Network Mailing List (PSN-L) From: barry lotz Subject: Re: Barometric floats and flat springs Date: Mon, 19 Oct 1998 19:58:51 -0700 Brett I am aware of invar(I think that's how it's spelled). We use a 0.75"x11" cylinder of it at work for a reference length in measuring the movement of concrete. I'll check McMaster Carr. Regards Barry Brett Nordgren wrote: > Barry, > > Yes, I agree that the elastic modulus of the spring probably does change > with temperature. You could infer that by noting that expensive mechanical > watches have balance wheel hairsprings made from a material called Elinvar, > described as an alloy which has an elastic modulus that doesn't vary with > temperature. > > I think I remember reading that the Streckeisen STS-1 vertical (and > possibly others) uses a leaf spring made of Elinvar. > > Does anyone know who makes Elinvar or anything about its mechanical > properties? > > It would be interesting to find out how much a small sheet would cost. > Could be that, if there's enough interest, one could get together an order > large enough for the manufacturer's minimums. > > Regards, > > Brett _____________________________________________________________________ Public Seismic Network Mailing List (PSN-L) From: "Al Allworth" Subject: RE: Barometric floats and flat springs Date: Mon, 19 Oct 1998 21:00:15 -0700 > -----Original Message----- > From: barry lotz [mailto:gbl@........ > Sent: Monday, October 19, 1998 6:13 PM > To: PSN-L Mailing List > Subject: Re: Barometric floats and flat springs > > > Brett > I have been working with two of Sean Thomas' VBB style units > for a couple > of months now. It seems that the biggest variation I have found ( as Sean > Thomas has mentioned in the past ) is temperature. I think that > the temperature > affects the stiffness of the spring by changing the length or > modulus. I have > yet to find data that support the fact that metal(steel) under > stress may have > a modulus which varies slightly with temperature. I did a rough > calc and the > length change appears to me second order. > > Regards > > Barry Barry and all, I mentioned the idea of plating copper on one side of the spring to temperature compensate it. Has anyone given further thought to this? Copper is easy to plate and could be done at home. The problem of how much copper to plate should not be too difficult to resolve. Al Allworth _____________________________________________________________________ Public Seismic Network Mailing List (PSN-L) From: barry lotz Subject: Re: Barometric floats and flat springs Date: Mon, 19 Oct 1998 21:20:04 -0700 Al I have had pretty good results with a thermometer bymetal coil with the coil center fixed to the base and the free end resting under or over the sensor beam. The trick is how far to put it from the hinge so as to not over compensate. Sean Thomas has discussed this prior. It works pretty well. I haven't tried other options as yet. Regards Barry Al Allworth wrote: > Barry and all, > > I mentioned the idea of plating copper on one side of the spring > to temperature compensate it. Has anyone given further thought to > this? Copper is easy to plate and could be done at home. The problem > of how much copper to plate should not be too difficult to resolve. > > Al Allworth > > ___________________________________________ _____________________________________________________________________ Public Seismic Network Mailing List (PSN-L) From: Greg Subject: Re: Barometric floats and flat springs Date: Tue, 20 Oct 1998 04:48:23 +0000 Brett Nordgren wrote: > Does anyone know who makes Elinvar or anything about its mechanical > properties? I searched around the internet for you a bit. I found the following: http://www.elinvar.com/ is a company named after the metal, but having nothing really to do with it. They are a temp agency. http://asuwlink.uwyo.edu/~metal/invar.html is a description of invar that mentions Elinvar. ,Greg _____________________________________________________________________ Public Seismic Network Mailing List (PSN-L) From: "Al Allworth" Subject: RE: Geophone amps Date: Mon, 19 Oct 1998 22:11:55 -0700 S-T Morrissey I don't know if you mentioned it before but I have a question: When you remove the flat spring from your seis does it completely straighten or is it deformed by the bending? I tried the metal of a cheap looking taping knife and it appeared to stay somewhat bent. I didn't buy it because of that. They also had some similar things called paint guards or something like that. They were blued steel but also seemed too soft for a spring. Al Allworth _____________________________________________________________________ Public Seismic Network Mailing List (PSN-L) From: Brian Chesire Subject: Re: Barometric floats and flat springs--Elinvar Date: Tue, 20 Oct 1998 07:49:57 -0700 I think what he's refering to is "ELGILOY" a trademark of "Eligiloy Limited Partenership", It was an outgrowth of the Elgin or Hamilton watch company. As I understand it, Elgiloy was developed as zero temperature coefficient spring material for pre-digital chronometers and watches. I don't know if they have a web site but they are located in Elgin, IL. Brian WA5PPO Tucson, AZ _____________________________________________________________________ Public Seismic Network Mailing List (PSN-L) From: meredith lamb Subject: PSN TRADING POST; pre-web site/page start up Date: Tue, 20 Oct 1998 11:24:46 -0600 Hi All, Have volunteered to do the web page maintenance of the PSN Trading Post on Larry Cochranes generiously hosted Redwood City PSN site: http://psn.quake.net/ The page is ready to go, but FIRST, we need some "advertisements" to fill the block spaces, and then the html file can be placed on his system. So....if you have some items that maybe of interest to others, please submit them as soon as possible to myself, via e-mail to: psnseismograph52@.......... Or regular mail: Meredith Lamb 715 S. Pecos St. Denver, Colorado USA 80223 The following text is the present makeup and guidelines of the page yet to appear: ******************************************************************** PSN Trading Post Last update: --/--/98 The followings is a list of items PSN'ers or creditable outside partys have submitted for Sale/Trade or they want. Any additions, mistakes corrections, subtractions, conflicts between partys, and international shipping and monetary exchange problems of items hereon are SOLELY the responsiblity of the individual submission/answering partys involved. I ask that any one individual submit no more than 2 items at a time per block available. Any inactive item over 1 month of posting age will be deleted unless judged to be of substantial PSN interest. Please make the items words as short and concise as possible and include your email address or complete address if necessary. Please...only submit Sale/Trade items with a real or potential seismological use or as an accessory/assistance item, i.e.; computers, PC-cards, earth science books etc: hmmm..you might have to even explain its relationship-ha. Be aware that alot of answering individuals may be starting their own stations and have little or no equipment to trade. Above all....have fun checking the list! ............................................................................................................................... .. Example: 11/1/98... For trade: 1 used home brew.......seismometer, up to 15s period, oil damping. Size 2' X 3' X 1.5' high normally, condensed on shipment. Weighs 70lbs. Send email to........., see the critters photo at my web site, http://www................internet address, or, (address). Want........in exchange or, contact me with what you offer, and we'll go from there. ............................................................................................................................... ...... Please send you final corrected draft of the PSN Trading Post E-Mail item too: Meredith Lamb, at: psnseismograph52@.......... OR 715 S. Pecos St. Denver, Colorado USA 80223 ............................................................................................................................... ...... Submitting individuals items follow this heading and text and are set in block spaces. **************************************************************************** Hopefully over time, the items listed can assist all individuals interested in either starting up their stations, or adding on to their improvement. Who knows....maybe some of the professional stations, nets, government sources, may even sometime list their unused equipment, and it could find its way into amateur hands.....wouldn't that be something!!! If you're an "old timer" with unused equipment, and can list some items, it can go along ways toward helping start others with strong interests, but who face a lack of equipment sources, at (hopefully) a reasonable price/trade range. The appearance of the web page on the site now depends on submissions to the page. So......go ahead and put me to work......I'll try to put them on the page asap. Who knows it maybe just days till then??? Uhhhh.....what do you have or want???, send to me, and NOT, to the PSN mailing list please. Any suggestions or improvements to the makeup of the page will be seriously considered of course; changes to this or anything are realistically inevitable, as with everything. If your have more than 2 items; and they would realistically be considered of intense interest by, say a beginner; due consideration will be extended to expanding the block on the web page of course. Thanks, Meredith Lamb Hi All,

Have volunteered to do the web page maintenance of the PSN Trading Post on
Larry Cochranes generiously hosted Redwood City PSN site:  http://psn.quake.net/
The page is ready to go, but FIRST, we need some "advertisements" to fill the block
spaces, and then the html file can be placed on his system.  So....if you have some
items that maybe of interest to others, please submit them as soon as possible to
myself, via e-mail to:       psnseismograph52@..........     Or regular mail:
Meredith Lamb    715 S. Pecos St.   Denver, Colorado  USA   80223

The following text is the present makeup and guidelines of the page yet to appear:
********************************************************************
PSN Trading Post
Last update:  --/--/98
The followings is a list of items PSN'ers or creditable outside partys have submitted
for Sale/Trade or they want.
Any additions, mistakes corrections, subtractions, conflicts between partys, and
international shipping and monetary exchange problems of items hereon are
SOLELY
the responsiblity of the individual submission/answering partys involved.  I ask that
any one individual submit no more than 2 items at a time per block available.  Any
inactive item over 1 month of posting age will be deleted unless judged to be of
substantial PSN interest.  Please make the items words as short and concise as
possible and include your email address or complete address if necessary.
Please...only submit Sale/Trade items with a real or potential seismological use or as
an accessory/assistance item, i.e.; computers, PC-cards, earth science books etc:
hmmm..you might have to even explain its relationship-ha.  Be aware that alot of
answering individuals may be starting their own stations and have little or no
equipment to trade.  Above all....have fun checking the list!
........................................................................................................................... .....
Example: 11/1/98... For trade: 1 used home brew.......seismometer, up to 15s
period, oil damping.  Size 2' X 3' X 1.5' high normally, condensed on shipment.
Weighs 70lbs.  Send email to........., see the critters photo at my web site,
http://www................internet address, or, (address).  Want........in exchange or,
contact me with what you offer, and we'll go from there.
........................................................................................................................... .........
Please send you final corrected draft of the PSN Trading Post E-Mail item too:
Meredith Lamb, at: psnseismograph52@..........   OR   715 S. Pecos St.
Denver, Colorado USA  80223
........................................................................................................................... .........
Submitting individuals items follow this heading and text and are set in block spaces.
****************************************************************************

Hopefully over time, the items listed can assist all individuals interested in either starting up
their stations, or adding on to their improvement.  Who knows....maybe some of the
professional stations, nets, government sources, may even sometime list their unused
equipment, and it could find its way into amateur hands.....wouldn't that be something!!!

If you're an "old timer" with unused equipment, and can list some items, it can go along
ways toward helping start others with strong interests, but who face a lack of equipment
sources, at (hopefully) a reasonable price/trade range.

The appearance of the web page on the site now depends on submissions to the page.  So......go ahead and put me to work......I'll try to put them on the page asap.  Who knows it maybe just days till then???   Uhhhh.....what do you have or want???, send to me, and NOT, to the PSN mailing list please.  Any suggestions or improvements to the makeup of the page will be seriously considered of course; changes to this or anything are realistically inevitable, as with everything.

If your have more than 2 items; and they would realistically be considered of intense interest by, say a beginner; due consideration will be extended to expanding the block on
the web page of course.

Thanks,

Meredith Lamb
  From: GeE777@....... Subject: Seismic Event TEST TEST Date: Tue, 20 Oct 1998 15:16:15 EDT THE FOLLOWING IS A TEST I AM ABLE TO SEND A GRAPH OF MY RECORDED SEISMIC EVENTS OVER AOL I DON"T KNOW IF IT WORKS OUT OF AOL THIS IS A TEST TO SEE IF IT MAKES SENSE ON THE NET Recorded a seismic event at this station. Approximate Time XX XX XX Estimated strength- YYYY Estimated distance from this station- ZZZZZ Station coordinance 33 Deg. 53.87 min North 118 Deg. 04.50 min. West George Erich Seismic Exploration Consultant P. O. Box 2011 Norwalk, CA 90650 U. S. A. e-mail GeE777@....... END OF TEST _____________________________________________________________________ Public Seismic Network Mailing List (PSN-L) From: Karl Cunningham Subject: Re: Barometric floats and flat springs--Elinvar Date: Tue, 20 Oct 1998 13:34:16 -0700 Thought you all might be interested in the following: There are several alloys that exhibit near zero temperature coefficient of modulus of elasticity, at least over the range near room temperature. According to the Machinery Handbook, 22rd edition, they are: Elinvar (Trade name of Society Anon. de Commentry Fourchambault et Decazeville, Paris, France) -- The first constant-modulus alloy used for hairsprings in watches. Variations are known by Elinvar Extra, Durinval, Modulvar, and Nivarox. Ni-Span C (Trade name of International Nickel) -- Very popular constant-modulus alloy. Useful up to 60K - 80K psi stress. Iso-Elastic (Trade name of John Chatillon & Sons) -- Useful to 40K to 60K psi. Used in dynamometers, instruments, and food-weighing scales. Elgiloy (Trade name of Elgin National Watch Co) -- Also known as 8J Alloy, Durapower, and Cobenium. NON-MAGNETIC alloy useful up to 75K psi stress. Used in watches and instrument springs. Dynavar (Trade name of Hamilton Watch Co) -- Also NON-MAGNETIC. Similar characteristics and uses as Elgiloy. I'd be very interested in going in with others to purchase some metal. Karl Cunningham La Mesa, CA. PSN station #40 karlc@....... _____________________________________________________________________ Public Seismic Network Mailing List (PSN-L) From: meredith lamb Subject: Magnets source.... Date: Tue, 20 Oct 1998 17:28:07 -0600 Received the latest Herbach and Rademan surplus catalog today. Pages 78 & 79, show a variety of magnets. http://www.herbach.com You can order a catalog via the internet on their bottom home page. If you're into S-G type seismo construction, via the original construction, I see Alnico bar magnets of 3 sizes/diameters/lengths. They also have a variety of much stronger gauss fields bar neodymium magnets of various diameters, but not long lengths. Don't see any 4 pole variety neodymium magnets here, but they do have the 2 pole variety, which could work for some projects. Catalog comes wide spectrum....mechanical, power supplies, other electronics etc...115 pages. -- Meredith Lamb <><><><><><><><><><><><><><><><><><><><><><><><><><><><><><><><><><><><> Main Web site: http://www.users.uswest.net/~psnseismograph52/Index.html and secondary site: http://www.geocities.com/ResearchTriangle/Facility/1739/index.html <><><><><><><><><><><><><><><><><><><><><><><><><><><><><><><><><><><><> _____________________________________________________________________ Public Seismic Network Mailing List (PSN-L) From: meredith lamb Subject: Two web sites with "zero" temp coeff metals Date: Tue, 20 Oct 1998 18:21:27 -0600 http://www.thomasregister.com/olc/eaglealloys/alloys.htm Eagle Alloys Corp. lists Elgiloy, various invar compositions, nickel 902 (Ni-Span-C). Site does little more than list the items it can sell. Why are commercial sites so empty??-ha Another web site: http://www.springs.co.uk/product.htm Doig Spring & Engineering co. ltd. They make coil & leaf springs. They list elgiloy and Ni-Span-C. Meredith Lamb <><><><><><><><><><><><><><><><><><><><><><><><><><><><><><><><><><><><> Main Web site: http://www.users.uswest.net/~psnseismograph52/Index.html and secondary site: http://www.geocities.com/ResearchTriangle/Facility/1739/index.html <><><><><><><><><><><><><><><><><><><><><><><><><><><><><><><><><><><><> _____________________________________________________________________ Public Seismic Network Mailing List (PSN-L) From: "David A. Nelson" Subject: large NZ quake today Date: Wed, 21 Oct 1998 12:33:56 +1200 U.T.: 1998 October 20 2002 NZST: 1998 October 21 9.02 a.m. Lat, Long: 43.49S 169.08E Location: 44 km north of Haast Focal depth: 12 km Magnitude: 6.1 Felt widely in the lower South Island with some damage reported. Dave this event overloaded all my sensors, one day i will get a strong motion seismometer Co-ordinator: New Zealand Public Seismic Network Dave A. Nelson ZL4TBN 24 Jensen St., Green Is., Dunedin, South Is.. New Zealand. http://psn.quake.net/dave/home.htm IF there indeed are other parallel universes... I can now rest in the knowledge, that in at least one of them, I am filthy rich and drive a red Ferrari _____________________________________________________________________ Public Seismic Network Mailing List (PSN-L) From: Brett Nordgren Subject: Re: Barometric floats and flat springs--Elinvar Date: Tue, 20 Oct 1998 20:31:43 -0400 Karl, Thanks for that most excellent report on Elinvar, etc. But there's good news and bad news. The good news is obviously that there exist spring materials which have a stable elastic modulus. The bad news is that those materials are only good for, say, 75,000 psi stress (vs 180,000 or so for spring steel). The computer says that if you reduce the spring thickness to .011" you can get down to 75,113 psi in the assumed STM-5 configuration. However that makes the force go down to 1.13 pounds. To get it back to the originally assumed 4.95 pounds, you have to increase the spring width from 3.5" to 15". Ouch! Makes great watch hairsprings, though. Brett _____________________________________________________________________ Public Seismic Network Mailing List (PSN-L) From: "Rex Klopfenstein, Jr." Subject: Oscillator Circuit Update Date: Tue, 20 Oct 1998 20:48:20 -0400 Sean I have just completed the assembly and tested of the oscillator portion of the VRDT circuit you have posted on your web page. I seems to work (will have to wire into the VRDT coils to see what sine wave looks like under load). I however did find several circuit errors. The first, the two 1N914 diodes on either side of the 10K pot in the voltage reference section. They are shown backwards. The other error is in the area of the 4018 counter. First, the lead connecting the 100K resistor to pin 1 of 4018 should be disconnected. The wire from the 100K resistor should be connected to common. The wire that connects the 100K/309K/221K/309K resistors and .001mF capacitor to pin 11 of 4018 should be removed from pin 11. The rest of the circuit remains unchanged. Finally, install a jumper between pin 1 and 11. A complete discussion of sine wave generation can be found in "CMOS COOKBOOK" by Don Lancaster (Howard Sam, Indianapolis) 1977, page 325-330. The exact circuit used is shown except all resistors are smaller by exactly a factor of 10. Maybe this resistance increase is to reduce the current demand? I will try to update the schematic I have on my web page this weekend and post. Rex Klopfenstein, Jr. Bowling Green, OH rklofen@......... www.wcnet.org/~rklopfen _____________________________________________________________________ Public Seismic Network Mailing List (PSN-L) From: S-T Morrissey Subject: leaf spring material Date: Tue, 20 Oct 1998 20:02:33 -0500 (CDT) Al, Karl, and company. Al asked if the spring material I have used exhibited any residual deformation. In general it does not, even if it is bent into a closed arc. In some of my earlier designs, I was able to form an angle across the end with the vise. But I have noticed that some of the hardware store scrapers are not really blued spring steel, but softer material or even stainless. Karl has done some fine research on elinvar and other constant- modulus with temperature materials. I noticed the Chantillion and Sons company: they have long been a supplier for iso-elastic coiled "zero-length" springs for commercial seismometers. I'm not sure that such materials are available in sheet form for use as a leaf spring. I guess we will have to see if Bretts' analysis would show that a constant modulus will help. I have long thought, perhaps in error, that the problem with the fully curved leaf spring is that the outer surface is in fact stretched more than the inside surface, so is in effect longer on the outside, which would expand more with temperature. This would give it the negative temperature behavior that we see: the spring lowers the boom as the temperature increases. From what I have seen of other leaf spring applications, the curvature is minimized, but one end is clamped. Regards, Sean-Thomas _____________________________________________________________________ Public Seismic Network Mailing List (PSN-L) From: barry lotz Subject: Re: leaf spring material Date: Tue, 20 Oct 1998 18:40:54 -0700 Sean Thomas That is what I originally thought also. I checked it by figuring the length of the inside and outside circumference and the length change of each for a reasonable temp change. I then figured the new diameter based on the new lengths and got very little change, though it was in the correct direction Regards Barry S-T Morrissey wrote: > Snip---. > I guess we will have to see if Bretts' analysis would show that a > constant modulus will help. I have long thought, perhaps in error, that > the problem with the fully curved leaf spring is that the outer surface > is in fact stretched more than the inside surface, so is in effect longer > on the outside, which would expand more with temperature. This would give it > the negative temperature behavior that we see: the spring lowers the > boom as the temperature increases. From what I have seen of other leaf > spring applications, the curvature is minimized, but one end is clamped. > > Regards, > Sean-Thomas > _____________________________________________________________________ Public Seismic Network Mailing List (PSN-L) From: barry lotz Subject: New Event? Date: Tue, 20 Oct 1998 19:29:48 -0700 Hi All Is anyone picking a teleseismic event now? (about 1:30 UTC). Regards Barry _____________________________________________________________________ Public Seismic Network Mailing List (PSN-L) From: George Harris Subject: Re: Barometric floats and flat springs Date: Mon, 19 Oct 1998 23:27:24 +0000 Al Allworth wrote: > > I mentioned the idea of plating copper on one side of the spring > to temperature compensate it. Has anyone given further thought to > this? Copper is easy to plate and could be done at home. The problem > of how much copper to plate should not be too difficult to resolve. > > Al Allworth > Al, The problem with plated copper would be that it is very soft. Since it would be on the surface and thus highly stressed, it would cause a hysteresis effect, I suspect. George Harris _____________________________________________________________________ Public Seismic Network Mailing List (PSN-L) From: david alexander Subject: Re: New Event? Date: Tue, 20 Oct 1998 21:09:34 -0700 don't have any instruments yet but i do think that i felt it north of seattle. thought that the dryer was running but when i looked nothing was running but the house was shaking a little. will be interesting to see where it was. dave alexander k7da barry lotz wrote: > > Hi All > Is anyone picking a teleseismic event now? (about 1:30 UTC). > Regards > Barry > > _____________________________________________________________________ > > Public Seismic Network Mailing List (PSN-L) > > To leave this list email listserver@............. with the body of the > message: leave PSN-L _____________________________________________________________________ Public Seismic Network Mailing List (PSN-L) From: "J. D. Cooley" Subject: Re: New Event? Date: Wed, 21 Oct 1998 06:07:20 -0700 At 07:29 PM 10/20/98 -0700, you wrote: >Hi All > Is anyone picking a teleseismic event now? (about 1:30 UTC). > Regards > Barry > > > I don't know where you live, Barry, but probably this is the one: == PRELIMINARY EARTHQUAKE REPORT == Rapid Earthquake Location Service U.S. Geological Survey, Menlo Park, California U.C. Berkeley Seismological Laboratory, Berkeley, California Version 2: Updates lower and earlier versions of this earthquake report This event has been reviewed by David Oppenheimer-USGS A LIGHT EARTHQUAKE OCCURRED AT 01:31 AM PDT Wednesday, Oct 21, 1998. THE MAGNITUDE 4.5 (ML) EVENT IS LOCATED 13 MILES WSW OF PORTOLA, CA THE HYPOCENTRAL DEPTH IS 12.6 MILES. Earthquake location is poorly constrained because it occurs near edge of seismic network. PRINCIPAL EARTHQUAKE PARAMETERS _______________________________ Magnitude : 4.49 ML Event Date & Time : 10/21/1998 01:31:01 AM PDT 10/21/1998 08:31:01 UTC Location : 39.7247 N, 120.6768 W : (39 deg. 43.48 min. N, 120 deg. 40.61 min. W) Depth : 20.2 km. deep ( 12.6 miles) Location Quality : Fair 20 km ( 13 miles) WSW (242 degrees) of Portola, CA 33 km ( 20 miles) SE (136 degrees) of Quincy, CA 38 km ( 23 miles) W (278 degrees) of Loyalton, CA 52 km ( 32 miles) SSE (153 degrees) of Greenville, CA 59 km ( 37 miles) NNE ( 29 degrees) of Nevada City, CA 65 km ( 41 miles) NNE ( 30 degrees) of Grass Valley, CA ADDITIONAL EARTHQUAKE PARAMETERS ________________________________ number of phases : 213 rms misfit : 0.07 seconds horizontal location error : 0.9 km vertical location error : 2.6 km maximum azimuthal gap : 219 degrees distance to nearest station : 58. km In region 2 (062) WALKER LANE event ID: 40081380 "JD" _____________________________________________________________________ Public Seismic Network Mailing List (PSN-L) From: Brett Nordgren Subject: Re: Barometric floats and flat springs Date: Wed, 21 Oct 1998 09:22:18 -0400 Sean-Thomas, I think I've satisfied myself that the major temperature effect on the spring performance is change of elastic modulus and not thermally-induced stresses, by the following arguments. In his "Theory of Elasticity" book, in analyzing the stress effects of *non uniform* temperatures, Timoshenko states that for analysis, thermal effects can be treated separately from "spring" effects and then combined at the end. Following that approach, a *uniform* temperature change could be analyzed by imagining that we could start out with a second spring that's been permanently bent so that it can be removed from the seismograph, and still retain the exact shape of the installed spring with no force applied. When heated *uniformly* it expands in all dimensions, just as if you had changed the scale factor in the drafting program. If you warmed it by 10 degrees C, all its dimensions would increase by slightly more than 0.01%, *including the opening*. In effect, "length" will tend to increase with temperature, thus increasing the force once it's been pushed back to its original length and summed with the installed spring. Opposite what you're seeing, I think. In Shanley, "Strength of Materials" he describes five characteristics of the Modulus of Elasticity. Number 4 is: "The modulus of elasticity decreases with increasing temperature - This can be explained by atomic theory, but for engineering purposes the value of E is best determined experimentally at the desired temperature". Shanley also states that there are no spring forces (stresses) which result directly from uniform thermal expansion (thermal strain). There are only those which arise when you try to constrain the expansion in some way. The difficulty that's arising in using alloys designed for stable elastic modulus, is that they aren't as strong as spring steel, by a factor of two or three. A 0.018" x 12 " sheet, bent past 180 degrees would either break or permanently bend. So the problem is more than just replacing the steel blade with an identical one made from a new material. Found an excellent Web site with properties for all kinds of materials, not just metals. http://www.matls.com/ (That's "L" as in MATLS) For NI-SPAN-C / Alloy 902, one of the alloys that's been discussed, the direct URL is: http://www.matls.com/SpecificMaterial.asp?bassnum=NINC83&group=General Well, back to the drawing board. Brett _____________________________________________________________________ Public Seismic Network Mailing List (PSN-L) From: robert barns <75612.2635@..............> Subject: Re: Barometric floats and flat springs Date: Wed, 21 Oct 1998 10:07:40 -0400 Brett, I tried excite, altavista and infoseek to get data about Elinvar and found nothing interesting except a possible clue to sources. Maybe the Hamilton Watch Co. or the Waltham Watch Co. As you indicated, watch makers are intensely interested in the elastic modulus as a function of temperature. The following quote is from "The Science of Clocks & Watches" by AL Rawlings, 3rd., ed., 1993. (Fascinati= ng reading for those interested in mechanical devices.) "If l is the length of a spring, t its thickness, b its breadth (the section being supposed rectangular) and E its modulus of elasticity, then= Q =3D C * t^3*b*E/l where C is some constant depending on the units chosen. "A rise in temperature in the case of steel, will have the effect of increasing all three dimentions of the spring by the same proportion. Th= e changes in b and l will cancel out, but the increase in t^3 will make the= spring stiffer. The expansion of steel is given in the tabel on p 46 [gives 11ppm/deg C]. If we take three times this expansion, we shall get= approx. the corresponding change in the value of t^3 and therefore of Q, namely 33 ppm increase due to the change in dimensions of the spring caus= ed by the temp, rise of 1 deg C, provided that E remains constant. This mak= es the vibration quicker with increased temperature. "But E for steel also varies with temp., for the material becomes more yielding as it gets warmer. It has been found that at normal temps. E decreases about 240 ppm/deg C. This will make the period of vibration longer and the watch will lose from the effect of heat on the hairspring.= " Starting on p 193 is a long discussion of other alloys. Guillaume devised an alloy of iron and nickel called Invar (he got a Nobel prize fo= r this in 1920) and another called Elinvar (iron, nickel, chromium, mangane= se and tungsten). There are other alloys used in watch hairsprings--Nivarox= and Conel are mentioned. In all of these alloys, heat treatment affects the temp. coe. of E. The National Assoc. of Watch and Clock Collectors site at www.nawcc.c= om is interesting. Bob Barns _____________________________________________________________________ Public Seismic Network Mailing List (PSN-L) From: Brett Nordgren Subject: Re: Barometric floats and flat springs Date: Wed, 21 Oct 1998 12:45:26 -0400 Bob, That's great info. It's just what's needed to put together the whole picture. By the way, In my previous note to Sean-Thomas, I'd completely forgotten the obvious fact that the gross dimensions of the spring, in particular the thickness, do change with temperature, and that effects the stiffness of the spring and needs to be considered. Just tried a brute-force approach and put the changes into the spreadsheet for the STM-8 and looked at the changes in the results. If the thickness, length and width are all increased by 11 ppm and E is decreased by 240 ppm as you suggest, then near the (12cm, 2.25kg) point, the force changes by about -198ppm and the gap increases by 11ppm. After the spring is squeezed back to its original gap, the net force change comes out as about -161ppm or to be accurate, -161ppm/degC That's about -0.36mg/degC in the spring force. (or the corresponding in Newtons or dynes with a "g" in there somewhere). Anywhere close to what's being observed? Brett At 10:07 AM 10/21/98 -0400, you wrote: The expansion of steel is given in the tabel on p 46 >[gives 11ppm/deg C]. If we take three times this expansion, we shall get >approx. the corresponding change in the value of t^3 and therefore of Q, >namely 33 ppm increase due to the change in dimensions of the spring caused >by the temp, rise of 1 deg C, provided that E remains constant. This makes >the vibration quicker with increased temperature. > "But E for steel also varies with temp., for the material becomes more >yielding as it gets warmer. It has been found that at normal temps. E >decreases about 240 ppm/deg C. This will make the period of vibration >longer and the watch will lose from the effect of heat on the hairspring." _____________________________________________________________________ Public Seismic Network Mailing List (PSN-L) From: "James M Hannon" Subject: Re: Leaf spring analysis Date: Wed, 21 Oct 1998 13:37:03 -0500 Brett, I have been trying to understand your leaf spring analysis and something is troubling me about the spring force curves. My understanding of the mechanical period of the mass spring combination is that if you want a long period you need the rate at which the force changes with amount of bending to be small. I may be all wet but I expected to see a portion in the middle of the curve that was almost vertical. This is based on my crude attempts at measuring a spring, bending one with my fingers and the mechanical period that is described as being obtainable with this sort of spring. On the other hand I attempted to calculate the period based on your theoretical curves for the STM-8 spring and came out with 1.3 seconds at the STM-8 operating point marked on the data. Sean's mathcad worksheet shows using 2.0 seconds for the mechanical period, which agrees well enough with the calculation of 1.3 sec. Jim Hannon _____________________________________________________________________ Public Seismic Network Mailing List (PSN-L) From: S-T Morrissey Subject: Re: Oscillator Circuit Update Date: Wed, 21 Oct 1998 15:15:56 -0500 (CDT) Rex, Thanks for the update on the oscillator schematic. Since it is a new drawing from the original hand drawings, I suspected that there would be typos. However, we made about 50 of them, and they still work. THe temp comp diodes are clearly reversed. In fact, we don't actually use a pot for the LM136, but a 10k R on one side of the adjustment pin, and select the resistor for the other side with a decade box, and use the closest 1% from our collection. Also. the PC board is laid out for the 4047, and we carved the foils to adapt it for the Statek rather than re-printing it. Regarding the 4018, the error is the connection between the three output Rs and the 100k from pin 1 to pin 11. The values were changed, and 100k was used rather than a jumper, to conserve power. THe remote tiltmeter systems in Alaska had to run for two years from the battery pack, so our power budget was 55 ma at 13 volts, or about 700 milliwatts total. The amplifier used at A1 for the regulated voltage is actually a micropower LM4250 with a 1meg current programming R in the original version. I have corrected the my drawing and will post it later this week, along the corrections of the amplifier/demodulator. Regards, Sean-Thomas _____________________________________________________________________ Public Seismic Network Mailing List (PSN-L) From: CARRJJ@....... Subject: Re: New Event? Date: Wed, 21 Oct 1998 16:25:57 EDT There was a Richter 3.3 event in Farmville, VA overnight. _____________________________________________________________________ Public Seismic Network Mailing List (PSN-L) From: "Rex Klopfenstein, Jr." Subject: Re: Oscillator Circuit Update Date: Wed, 21 Oct 1998 16:37:05 -0400 S-T Morrissey wrote: >100k from pin 1 to pin 11. I will try the 100K in place of jumper and see how it works. I will modify my schematic accordingly. -- Rex Klopfenstein, Jr. Bowling Green, OH rklopfen@......... www.wcnet.org/~rklopfen _____________________________________________________________________ Public Seismic Network Mailing List (PSN-L) From: "Giacomo Sperandini" Subject: R: large NZ quake today Date: Wed, 21 Oct 1998 22:43:38 +0200 thanks for information david. -----Messaggio originale----- Da: David A. Nelson A: psn-l@............. Data: mercoledì 21 ottobre 1998 2.29 Oggetto: large NZ quake today > > U.T.: 1998 October 20 2002 > NZST: 1998 October 21 9.02 a.m. > Lat, Long: 43.49S 169.08E > Location: 44 km north of Haast > Focal depth: 12 km > Magnitude: 6.1 > Felt widely in the lower South Island with some damage reported. > > > Dave > > this event overloaded all my sensors, one day i will get a strong motion >seismometer > > >Co-ordinator: >New Zealand >Public Seismic Network > Dave A. Nelson ZL4TBN > 24 Jensen St., > Green Is., Dunedin, > South Is.. New Zealand. > >http://psn.quake.net/dave/home.htm > >IF there indeed are other parallel universes... I can now rest in the >knowledge, that in at least one of them, I am filthy rich and drive a red >Ferrari > > >_____________________________________________________________________ > >Public Seismic Network Mailing List (PSN-L) > >To leave this list email listserver@............. with the body of the >message: leave PSN-L _____________________________________________________________________ Public Seismic Network Mailing List (PSN-L) From: barry lotz Subject: Re: New Event? Date: Wed, 21 Oct 1998 19:22:24 -0700 Actually that event blew my 16 bit card of the chart. I'll post it in a bit. Barry J. D. Cooley wrote: > > I don't know where you live, Barry, but probably this is the one: > > A LIGHT EARTHQUAKE OCCURRED AT 01:31 AM PDT Wednesday, Oct 21, 1998. > THE MAGNITUDE 4.5 (ML) EVENT IS LOCATED 13 MILES WSW OF PORTOLA, CA > THE HYPOCENTRAL DEPTH IS 12.6 MILES. > > Earthquake location is poorly constrained because it occurs near edge > of seismic network. > _____________________________________________________________________ Public Seismic Network Mailing List (PSN-L) From: S-T Morrissey Subject: leaf spring compensation Date: Wed, 21 Oct 1998 21:26:13 -0500 (CDT) Brett, You asked about the magnitude of the force change caused by temperature, suggesting about 0.36mg/degC. My experience is that it is considerably larger, at least on the prototypes. I originally used slider weights that weigh about 10 grams to trim the mass position . The trim mass effect of course depends on the mechanical period. It takes about 1cm of position change near the center of the boom, 10 cm from the hinges, to compensate for a 1 degC change. This force would be about doubled if applied above the lifting point of the spring, about 4 cm from the hinges. Of course, all this assumes that nothing else is contributing temperature changes. The motor driven weight of 20 grams needs about 7 turns at 32tpi, or about 0.5cm to compensate for about half the 1 degC temperature range, which causes a 7-volt offset of the mass position output, or about 200 microns with the feedback turned off. I need to modify the 4-second (BETA) unit with the period adjustment feature of the Gamma units to study this effect at longer periods. It may make matters worse. Since I have the motorized zeroing, I can repeat the experiment with more accuracy, since my microthermometers have milli-degree resolution, and I know the pitch of the thread of the translating rod, and can determine the weight. Unfortunately, I will have to disable the bimetallic compensation and the feedback first. With the single bimetallic spring compensation, the mass position change (with the feedback ON) is 20 microns/degC. I guess I will have to experiment on a prototype other than the one I am recording from. (by the way, did someone turn off the teleseisms greater than M=6 again?). Regarding the application of elinvar or a similar metal, the article in BSSA by Wielandt and Streckeisen describes the use of two metals installed in parallel which seems to accomplish the "cold thermostat" they describe. There is a photo of the sensor, as well as a diagram with dimensions of the semi-elliptical configuration. I have only seen the actual STS-1V spring momentarily while installing them: they don't work very well with the covers off. So we need to find some common material that gets more rigid as its temperature goes up. Currently, either the bimetallic element(s) or active electronic thermal feedback, with a very long time constant, have reduced the large temperature effect. Regards, Sean-Thomas _____________________________________________________________________ Public Seismic Network Mailing List (PSN-L) From: barry lotz Subject: N. Calif events Date: Wed, 21 Oct 1998 21:12:20 -0700 Hi All I was looking at the recent N.Cal events. It looks like the Sierra Nevada Fault may be trying to connect with the Mendocino Fault. I don't particularly want a front row seat. Regards Barry Separate Geographic comment: There are no members from two of the most seismicly active areas: South/Central America and Eastern Asia. . _____________________________________________________________________ Public Seismic Network Mailing List (PSN-L) From: Bonnie Subject: GeE777@........ Date: Wed, 21 Oct 1998 22:14:51 -0600 PSN-L@.............. Seismic Event TEST TEST Hi, that must have been the test that was held on television around 9:00 or 10:00 a.m. I live very near to Norwalk, CA. Thanks Bonnie the crafty crafter Net-Tamer V 1.10 - Registered _____________________________________________________________________ Public Seismic Network Mailing List (PSN-L) From: John Hernlund Subject: Re: N. Calif events Date: Wed, 21 Oct 1998 23:42:41 -0700 (MST) On Wed, 21 Oct 1998, barry lotz wrote: > I was looking at the recent N.Cal events. It looks like the Sierra > Nevada Fault may be trying to connect with the Mendocino Fault. I don't > particularly want a front row seat. > Regards > Barry Hi Barry, What was the time span you were looking at??? Which coordinates??? I would like to look at this also... ****************************************************************************** John Hernlund E-mail: hernlund@....... WWW: http://www.mc.maricopa.edu/academic/phy_sci/Geology/hernlund/ http://www.public.asu.edu/~hernlund/ ****************************************************************************** _____________________________________________________________________ Public Seismic Network Mailing List (PSN-L) From: Norman Davis WB6SHI Subject: Oh good grief... Date: Thu, 22 Oct 1998 07:40:28 I was wondering why I wasn't getting any traffic from this list. I gess when I left the last time I forgot to log back on. Old timers desease... Norman Davis WB6SHI Shingle Springs, Ca normd@............. http://www.directcon.net/normd/index.htm _____________________________________________________________________ Public Seismic Network Mailing List (PSN-L) From: Brett Nordgren Subject: Re: Leaf spring analysis Date: Thu, 22 Oct 1998 10:59:09 -0400 Jim, Good point. You are exactly right *if* the spring were the only factor. I've convinced myself that the "zero-length spring" (awful term) effect arises from a *combination* of the spring and the geometry. I'm currently trying to work that out for the STM-8. From what I have seen, period-extending geometries tend to have the spring acting at an angle to the boom, closer to the hinge at the top than at the bottom, and they usually have the mass set higher than the boom hinge. I'm hoping to get those numbers from Sean-Thomas, to see to what degree that's the case in his design. Then, using that geometry, you can graph the force required between the spring mounting points to balance the vertical force acting on the mass, vs the distance between those points, as the boom is rotated up and down. That gives you a second force-length curve. If that curve is adjusted to be tangent to the spring force-length curve at the equilibrium point, there will be virtually no net restoring force on the system as the boom moves slightly off equilibrium. That's the infinite-period situation you're looking for. If you set it up so that the curves intersect at a shallow angle, then the effective restoring force is finite, but small, and the natural period will just be extended. This will be a lot easier to see, once someone's done the graphs; but that's a few weeks off yet, for mine. Good luck with your project. Brett > > >Brett, >I have been trying to understand your leaf spring analysis and something is >troubling me about the spring force curves. My understanding of the >mechanical period of the mass spring combination is that if you want a long >period you need the rate at which the force changes with amount of bending >to be small. I may be all wet but I expected to see a portion in the >middle of the curve that was almost vertical. This is based on my crude >attempts at measuring a spring, bending one with my fingers and the >mechanical period that is described as being obtainable with this sort of >spring. > > On the other hand I attempted to calculate the period based on your >theoretical curves for the STM-8 spring and came out with 1.3 seconds at >the STM-8 operating point marked on the data. Sean's mathcad worksheet >shows using 2.0 seconds for the mechanical period, which agrees well enough >with the calculation of 1.3 sec. > >Jim Hannon > _____________________________________________________________________ Public Seismic Network Mailing List (PSN-L) From: "L&B Orme" Subject: Re: N. Calif events Date: Thu, 22 Oct 1998 09:01:42 -0700 I, too, would be interested in hearing all comments. I *have* a front row seat... Barb in Chico, CA. 98/10/14 15:05:46 40.84N 123.57W 26.1 4.0 8 mi SSE of WILLOW CREEK 98/10/17 06:32:14 39.37N 120.55W 11.5 3.4 20 mi W of TRUCKEE 98/10/19 07:01:43 40.45N 125.65W 4.9 3.3 69 mi W of PUNTA GORDA 98/10/19 08:16:28 40.48N 122.39W 0.0 2.2Md C* 11 km S of Redding, CA 98/10/19 08:21:47 40.21N 122.70W 12.8 2.1Md C* 38 km W of Red Bluff, CA 98/10/19 12:28:47 39.97N 120.88W 9.2 2.5Md D* 6 km NE of Quincy, CA 98/10/19 21:40:28 40.75N 122.31W 3.9 2.1Md C* 20 km NNE of Redding, CA 98/10/20 04:06:40 40.85N 123.33W 28.2 2.5Md B* 35 km WNW of Weaverville, CA 98/10/20 18:39:23 39.73N 120.65W 0.1 2.8Md C* 17 km WSW of Portola, CA 98/10/21 08:31:01 39.72N 120.68W 20.2 4.1Mw C* 20 km WSW of Portola, CA 98/10/21 08:36:03 39.75N 120.65W 12.4 3.0Md C* 17 km WSW of Portola, CA 98/10/21 09:02:25 39.75N 120.66W 6.8 2.6Md D* 17 km WSW of Portola, CA -----Original Message----- From: John Hernlund Date: Wednesday, October 21, 1998 11:44 PM >On Wed, 21 Oct 1998, barry lotz wrote: >> I was looking at the recent N.Cal events. It looks like the Sierra >> Nevada Fault may be trying to connect with the Mendocino Fault. I don't >> particularly want a front row seat. >> Regards >> Barry > >Hi Barry, > What was the time span you were looking at??? Which coordinates??? I >would like to look at this also... > >*************************************************************************** *** > > John Hernlund _____________________________________________________________________ Public Seismic Network Mailing List (PSN-L) From: John Hernlund Subject: Annales Geophysicae Article Date: Thu, 22 Oct 1998 09:07:22 -0700 (MST) For everyone that was interested, I posted the Annales Geophysicae Article at the following URL: http://www.public.asu.edu/~hernlund/articles/ The six pages are jpegs around 500 k in size... I didn't spend much time compressing them. ****************************************************************************** John Hernlund E-mail: hernlund@....... WWW: http://www.mc.maricopa.edu/academic/phy_sci/Geology/hernlund/ http://www.public.asu.edu/~hernlund/ ****************************************************************************** _____________________________________________________________________ Public Seismic Network Mailing List (PSN-L) From: "James M Hannon" Subject: Re: Leaf spring analysis Date: Thu, 22 Oct 1998 11:13:25 -0500 Brett, I suspect you are right about the geometry. I had convinced myself that for the leaf spring arrangnment the geometry didn't matter because of the very small displacments involved but it's the only way to get to the long periods. Since I want to tilt the whole insturment up at an angle I had better sit down and figure things out before I get too far along. Thanks, Jim Hannon Brett Nordgren on 10/22/98 09:59:09 AM Please respond to PSN-L Mailing List To: PSN-L Mailing List cc: Subject: Re: Leaf spring analysis Jim, Good point. You are exactly right *if* the spring were the only factor. I've convinced myself that the "zero-length spring" (awful term) effect arises from a *combination* of the spring and the geometry. I'm currently trying to work that out for the STM-8. From what I have seen, period-extending geometries tend to have the spring acting at an angle to the boom, closer to the hinge at the top than at the bottom, and they usually have the mass set higher than the boom hinge. I'm hoping to get those numbers from Sean-Thomas, to see to what degree that's the case in his design. Good luck with your project. Brett _____________________________________________________________________ Public Seismic Network Mailing List (PSN-L) From: Greg Subject: SDR and amps and such Date: Thu, 22 Oct 1998 17:27:31 +0000 I finally got my ADC card in my computer. Nothing is connected yet. I plan on playing with WWV this weekend and maybe an unamplified geophone. I was playing with the new SDR 2.5 last night and I pressed "E" to make it record an event. The question I have is, how do I go from the raw data file to an event file? The raw data is recorded as a file, but Winquake won't show it in the file window. I changed the directory, but appearantly it ignores everything that's not an event file. Maybe you can do it with SDR? I'm still flipping coins on an amplifier. I have at least four choices now. 1. Get Larry's amp. I like the idea of just giving him some more money and getting an amp that works quickly, but I'd like to burry the thing eventually. Larry's amp requires a power line. Unless I put it inside of all kinds of conduit and pipes and boxes, there's a fire hazard. 2. Try and make one like Sean-Thomas uses. I have to have the board laid out and manufactured. Then I have to buy all of the components and solder them in. As I've mentioned before, I can't solder very well. 3. Try and make a simpler one like http://met.univnorthco.edu/resource/amp.htm Similar problems with #2. I don't know enough about electronics so the qualities are a bit of an unknown. The parts are only about $20 though. 4. Talk to some really generous local electronics student and try and get them to design one for me. For a small fee of course. Students can mess things up and take a long time. An EE would cost too much almost certainly. So I guess I need some oppinions. I might remind you that I'll be connecting to a geophone. When I have a little more room, I might finish my Lehman and connect it up. TIA, Greg _____________________________________________________________________ Public Seismic Network Mailing List (PSN-L) From: S-T Morrissey Subject: seis drawing Date: Thu, 22 Oct 1998 12:50:08 -0500 (CDT) Brett, For your info and for the list: May I again ask that large binary attachments, such as .jpeg files, not be included in the email. I read mail at home here, on an old 486 dialed into the unix server at the U on an old modem that connects to an equally old modem on the server that has priority zip, so it shuts down if anything else happens on the mailhost access. I usually try to catch large emails by their size and aviod them, but sometimes I try to read a message that has a large embedded attachment, and can only wait for all the gibberish to go by, or hope the modem disconnects, which it did on your .jpeg file. Unfortunately, a number of people have sent me things that I have no way of opening or reading. If they were put somewhere that I can download them when I am using Netscape, I could look at them. Unfortunately, I am a bit old fashioned wrt PC,s; my computer experience began in 1960 on an IBM 1360 with punched cards and object decks, etc., but I have never had the time to get really saavy with what is currently available. Regarding your autosketch drawing: I assume that you have seen the current drawing of the seismometer geometry that I have posted. It has all the pertinent dimensions, but needs some corrections, like the proper angle of the suspensions at the ends of the leaf spring, and the bimetallic compensation has to be shown. I can update the drawing, which is autosketch, and export it as a .dxf file, and put it at: http://www.eas.slu.edu/People/STMorrissey/etc.export. It is done to scale, so unknown dimensions can be read with autosketch. Later I will clarify exactly what a "zero length" spring actually is, which will show why the leaf spring cannot actually be one. Regards, Sean-Thomas _____________________________________________________________________ Public Seismic Network Mailing List (PSN-L) From: W6JRF@....... Subject: Re: Oh good grief... Date: Thu, 22 Oct 1998 14:14:28 EDT Of all the things I have lost, I miss my mind the most..........Welcome Back Norm. I'm glad to see I not the only one that does things like that! But theres hope, you remembered how to get back!!!!! 73's Bob, W6JRF _____________________________________________________________________ Public Seismic Network Mailing List (PSN-L) From: meredith lamb Subject: Re: SDR and amps and such Date: Thu, 22 Oct 1998 13:01:45 -0600 > > > 1. Get Larry's amp. I like the idea of just giving him some more money > and getting an amp that works quickly, but I'd like to burry the thing > eventually. Larry's amp requires a power line. Unless I put it inside of > all kinds of conduit and pipes and boxes, there's a fire hazard. > Greg: I have one of Larrys 3 amp circuits. It should be close to the seismometer, but it doesn't have to be with the seismometer....i.e., bury the seismo (geophone), and have the amplifier as close to the output wires coming out of the ground as you can, or, use shielded wire cable to where ever you can put it safely. Larrys amplifiier is reliable, thats for sure. If you homebrew, as things normally go....it, or whatever homebrew circuit you try...may need repair, corrections etc....especially for people like me, who have little electronics experience. Reliable means less time, effort and really money in the long run. > 2. Try and make one like Sean-Thomas uses. I have to have the board laid > out and manufactured. Then I have to buy all of the components and > solder them in. As I've mentioned before, I can't solder very well. > > 3. Try and make a simpler one like > http://met.univnorthco.edu/resource/amp.htm > Similar problems with #2. I don't know enough about electronics so the > qualities are a bit of an unknown. The parts are only about $20 though. Greg: If I remember right, this circuits main IC, the chopper is obsolete, and no longer easily available. A substitute would have to installed, but, with that could come problems of a suitable matchup....and I'am no expert either. I like the circuit and text on this one mainly for the explanations given though....anything helps. That type of IC, is I think not even replaceable now. > > > 4. Talk to some really generous local electronics student and try and > get them to design one for me. For a small fee of course. Students can > mess things up and take a long time. An EE would cost too much almost > certainly. > > So I guess I need some oppinions. I might remind you that I'll be > connecting to a geophone. When I have a little more room, I might finish > my Lehman and connect it up. > > TIA, > Greg -- Meredith Lamb _____________________________________________________________________ Public Seismic Network Mailing List (PSN-L) From: Norman Davis WB6SHI Subject: Re: Oh good grief... Date: Thu, 22 Oct 1998 14:53:44 At 02:14 PM 10/22/98 EDT, you wrote: >Of all the things I have lost, I miss my mind the most..........Welcome Back >Norm. >I'm glad to see I not the only one that does things like that! But theres >hope, you remembered how to get back!!!!! 73's Bob, W6JRF > Good time to ask the question, Did ted ever get the emon working for the 150rs moduals? Norman Davis WB6SHI Shingle Springs, Ca normd@............. http://www.directcon.net/normd/index.htm _____________________________________________________________________ Public Seismic Network Mailing List (PSN-L) From: Norman Davis WB6SHI Subject: Re: N. Calif events Date: Thu, 22 Oct 1998 14:56:05 > >>On Wed, 21 Oct 1998, barry lotz wrote: >>> I was looking at the recent N.Cal events. It looks like the Sierra >>> Nevada Fault may be trying to connect with the Mendocino Fault. I don't >>> particularly want a front row seat. >>> Regards >>> Barry >> >>Hi Barry, >> What was the time span you were looking at??? Which coordinates??? I >>would like to look at this also... >> Yea, Its been nice and quiet til now. Looks like the whole state is starting back up from the map this week. Norman Davis WB6SHI Shingle Springs, Ca normd@............. http://www.directcon.net/normd/index.htm _____________________________________________________________________ Public Seismic Network Mailing List (PSN-L) From: Ted Blank Subject: Re: Oh good grief... Date: Thu, 22 Oct 1998 16:27:11 -0700 (PDT) Hi, Sorry, that little project didn't work out. The support for serial port I/O in the MS QuickBasic compiler is pretty spare, so after several weeks of trying I had to give up. It would have been nice to be able to collect data from a portable PC via serial port. Ted Blank San Jose, California On Thu, 22 Oct 1998, Norman Davis WB6SHI wrote: > At 02:14 PM 10/22/98 EDT, you wrote: > >Of all the things I have lost, I miss my mind the most..........Welcome Back > >Norm. > >I'm glad to see I not the only one that does things like that! But theres > >hope, you remembered how to get back!!!!! 73's Bob, W6JRF > > > Good time to ask the question, Did ted ever get the emon working for the > 150rs moduals? > > > Norman Davis WB6SHI > Shingle Springs, Ca > normd@............. > http://www.directcon.net/normd/index.htm > > > _____________________________________________________________________ > > Public Seismic Network Mailing List (PSN-L) > > To leave this list email listserver@............. with the body of the > message: leave PSN-L > _____________________________________________________________________ Public Seismic Network Mailing List (PSN-L) From: Ian Smith Subject: Re: Oh good grief... Date: Thu, 22 Oct 1998 13:59:44 -1000 Ted Blank wrote: > Hi, > Sorry, that little project didn't work out. The support for serial > port I/O in the MS QuickBasic compiler is pretty spare, so after several > weeks of trying I had to give up. It would have been nice to be able to > collect data from a portable PC via serial port. > Hi, I actually have my seismic pc running compiled QB and reading data from a serial port. Works great, 19200 baud 8 bit etc. I can forward the 1 line of code when I get home if you like. cheers _____________________________________________________________________ Public Seismic Network Mailing List (PSN-L) From: barry lotz Subject: Re: N. Calif events Date: Thu, 22 Oct 1998 18:59:34 -0700 John I was just looking at the USGS Menlo Park calif/nevada plot of recent events. My comment was part serious and part tongue in cheek. I have compiled a couple hundred years of calif/nevada events/ reported events but that's another story. Regards Barry John Hernlund wrote: > On Wed, 21 Oct 1998, barry lotz wrote: > > I was looking at the recent N.Cal events. It looks like the Sierra > > Nevada Fault may be trying to connect with the Mendocino Fault. I don't > > particularly want a front row seat. > > Regards > > Barry > > Hi Barry, > What was the time span you were looking at??? Which coordinates??? I > would like to look at this also... _____________________________________________________________________ Public Seismic Network Mailing List (PSN-L) From: Greg Subject: Re: SDR and amps and such Date: Fri, 23 Oct 1998 02:01:25 +0000 Thanks very much for the comments and responses. I'm still not certain about the preamp, because now there's another choice. ;) Next time I'll read the manual on SDR. You'd think I'd know better or something. ,Greg _____________________________________________________________________ Public Seismic Network Mailing List (PSN-L) From: Brett Nordgren Subject: Re: seis drawing Date: Thu, 22 Oct 1998 22:38:58 -0400 Sean-Thomas, Awfully sorry about the attachment, I'd hoped 19k wouldn't cause you any problems. I do have vertseis5.gif, if that's the drawing you were referring to, but was having a little difficulty finding a couple of the dimensions that I wanted. If sometime you could put the .dxf file in your export directory, I'd be most happy to get it and scale it directly. Regarding temperature effects: I will now write a hundred times "Kilograms times 1000 gives grams. Kilograms times 1,000,000 gives milligrams". Re-did the thermal effect computation a little more carefully. Final result at the 12 cm, 2.25 kg point is a spring force change of -193 ppm per degree C. Times 2.25 kg gives -433mg per degree C. I'm still not sure that completely agrees with your observations, but now at least I'm closer by three orders of magnitude. In looking at the period-lengthening geometry, I am getting a gut feeling that extending the natural period may also amplify the effects of thermal changes. That very much remains to be proven, but it's one of the things I want to look into. Until you mentioned it, I didn't know that the STS-1 had a multiple-material spring; and until I saw the numbers, yesterday, it wouldn't have made any sense. However, consider making a spring out of Ni-Span-C, and assume that it has a perfectly stable elastic modulus, E. Due to its coefficient of linear expansion of +7.6 ppm / deg.C its force will go up with temperature, a little more than 7.6 x 4, say +33 ppm per degree C. Perhaps by cleverly combining that with spring steel, which has a force that goes down with temperature, you can get them to offset each other's effects. Bet it's not easy! With all this discussion about temperature effects on the spring, we haven't talked about thermal expansion effects on other parts of the system, like for example boom-length. Have a feeling that's not trivial, either. Regards, Brett Nordgren _____________________________________________________________________ Public Seismic Network Mailing List (PSN-L) From: Edward Cranswick Subject: [Fwd: High school student participation at AGU] Date: Thu, 22 Oct 1998 22:28:52 -0600 -- Edward Cranswick Tel: 303-273-8609 US Geological Survey, MS 966 Fax: 303-273-8600 PO Box 25046, Federal Center cranswick@........ Denver, CO 80225-0046 USA E.M. Forster said, "Only connect". Catherine- One of the PSN presentations at December AGU (Blank & Froom): 11428 Ted Blank S 6605 7294 Seismic Monitoring in the Classroom - A Complement to the Traditional Middle School Earth Science Curriculum plans to include students from Almaden High School as presenters of their poster. How can we make an arrangement with AGU to give passes to the designated students? -Edward -- Edward Cranswick Tel: 303-273-8609 US Geological Survey, MS 966 Fax: 303-273-8600 PO Box 25046, Federal Center cranswick@........ Denver, CO 80225-0046 USA E.M. Forster said, "Only connect". From: Edward Cranswick Subject: Re: High school student participation at AGU Date: Thu, 22 Oct 1998 22:30:52 -0600 Catherine- Thank you very much for your help in this matter. You would think that if AGU supports outreach and education, they would want to start at home, so to speak, i.e., at AGU meetings. Do you know any other people that I also ahould contact about this? -Edward Catherine Johnson wrote: > Dear Edward, > > I'm forwarding your email to someone at AGU who will > know what to do about this. I don't think that there > is currently a satisfactory mechanism in place for > getting high school students to the meeting. I think > that technically they would have to register as non-members > which is really expensive (~$300 for the week). However, > AGU, after much persuasion has finally instigated an > undergraduate registration fee of $15 for one day and $30 for > the week, so I'm wondering if we can somehow get this kind of > rate. > > I'll let you know if I get any info from the folks at AGU. > > Best regards, > Catherine > > ----------------------------------------- > Dr. Catherine Johnson > Education and Outreach Program Manager > IRIS > 1200, New York Ave., #800 > Washington DC 20005 > > Tel: (202) 682 2220 > Fax: (202) 682 2444 > Email: catherine@........ > Web: http://www.iris.washington.edu/EandO > Personal web page: http://magellan.ciw.edu > ----------------------------------------- -- Edward Cranswick Tel: 303-273-8609 US Geological Survey, MS 966 Fax: 303-273-8600 PO Box 25046, Federal Center cranswick@........ Denver, CO 80225-0046 USA E.M. Forster said, "Only connect". _____________________________________________________________________ Public Seismic Network Mailing List (PSN-L) From: Edward Cranswick Subject: Re: Magnets source.... Date: Thu, 22 Oct 1998 23:48:45 -0600 My God, Meredith, I just checked out your websites, and I don't know what hit me!!! meredith lamb wrote: > Main Web site: http://www.users.uswest.net/~psnseismograph52/Index.html > > and secondary site: > http://www.geocities.com/ResearchTriangle/Facility/1739/index.html -- Edward Cranswick Tel: 303-273-8609 US Geological Survey, MS 966 Fax: 303-273-8600 PO Box 25046, Federal Center cranswick@........ Denver, CO 80225-0046 USA E.M. Forster said, "Only connect". _____________________________________________________________________ Public Seismic Network Mailing List (PSN-L) From: Edward Cranswick Subject: Re: Students at the AGU meeting. Date: Fri, 23 Oct 1998 00:12:11 -0600 Catherine- I have been out of the office for the last couple of days, picking up our instruments deployed to monitor the Pymatuning Earthquake , and so I am reading/replying to all your messages now. I will pass on this information about the AGU registration and membership. Thank you for your help. -Edward Catherine Johnson wrote: > Dear Ed, > > Here's the reply from AGU. The most $-effective option > is for the students to become AGU members and then they > can register as undergrads. Please let me know the names > of people who will be doing this so that I can pass the > info onto Frank Ireton at AGU in case there are any problems. > > Best regards, > > Catherine > > >From: FIreton@....... > >Date: Wed, 21 Oct 1998 09:49 -0400 (EDT) > >Subject: Students at the AGU meeting. > >To: catherine@........ > >MIME-version: 1.0 > >Status: > > > > Catherine, > > > > Sorry for the delay getting back to you. We had to get approval from > > Fred. He said that if they will join AGU they can register as > > undergraduate students. That will be a significant saving over > > member's registration prices. That information can be found on the AGU > > home page. Please keep me posted on the outcome. > > > > Frank > > > > ----------------------------------------- > Dr. Catherine Johnson > Education and Outreach Program Manager > IRIS > 1200, New York Ave., #800 > Washington DC 20005 > > Tel: (202) 682 2220 > Fax: (202) 682 2444 > Email: catherine@........ > Web: http://www.iris.washington.edu/EandO > Personal web page: http://magellan.ciw.edu > ----------------------------------------- -- Edward Cranswick Tel: 303-273-8609 US Geological Survey, MS 966 Fax: 303-273-8600 PO Box 25046, Federal Center cranswick@........ Denver, CO 80225-0046 USA E.M. Forster said, "Only connect". _____________________________________________________________________ Public Seismic Network Mailing List (PSN-L) From: Ian & Liz Subject: Re: Oh good grief...QB serial i/o Date: Thu, 22 Oct 1998 19:38:31 -1000 Hi, the magic line of QB for serial i/o is: OPEN "COM1:19200,N,8,2,CS,DS,RB64000,TB10240" FOR RANDOM AS #1 obviously in this case, 19200 baud, no parity, 8 bits data, 2 stop bits. CS and DS are important, they tell the port not to hardware handshake. Without them it will try to handshake with the connected device, and chances are those lines of the serial cable won't even be connected, causing the port to lock, and giving the appearance of being dead. RB and TB specify the size of the i/o buffers. Very useful for data taking as data will still buffer (at interrupt level) when the pc is busy doing other things (in most cases). If your system still appears to be dead then swap pins 2 and 3 on the 25 way D type connector. These are the Rx/Tx lines, and may be the wrong way round. Swap them back if that doesn't work and think again. It seems to be a law of physics that 1: it takes a minimum of 2 hours to get a serial line to work, 2: once working, never go wrong! Hope that helps. cheers Ian Smith _____________________________________________________________________ Public Seismic Network Mailing List (PSN-L) From: Larry Cochrane Subject: Re: Magnets source.... Date: Thu, 22 Oct 1998 23:27:10 -0700 I think it looks like the insides of a UFO.... Wheres Art Bell when you need him . -Larry PS: For those of you who don't know, Art Bell is (or was, he just went off the air for some reason) a radio talk show host that talks about anything weird. IMHO, a real nut case.... At 11:48 PM 10/22/98 -0600, Edward wrote: >My God, Meredith, I just checked out your websites, and I don't know what >hit me!!! > >meredith lamb wrote: > >> Main Web site: http://www.users.uswest.net/~psnseismograph52/Index.html >> >> and secondary site: >> http://www.geocities.com/ResearchTriangle/Facility/1739/index.html > _____________________________________________________________________ Public Seismic Network Mailing List (PSN-L) From: CARRJJ@....... Subject: Re: High school student participation at AGU Date: Fri, 23 Oct 1998 10:55:47 EDT There is also Project Inspire for high school student. It hunts for spherics and whistlers (natural radio signals). Bill Pine at Chaffey High School in Ontario, CA is the director. They can be found on the NASA web site. _____________________________________________________________________ Public Seismic Network Mailing List (PSN-L) From: lahr@.................. Subject: Re: QB serial AD input Date: Fri, 23 Oct 1998 10:31:23 -0600 (MDT) Ian, Which serial AD are you using? I'm interested in using the serial input for a portable display of a geophone for educational purposes. Basically the computer is just used as an oscilloscope. What sets the sampling rate? Would this same code work with Visual Basic? Thanks, JCLahr ################################## John C. Lahr ################################# Seismologist ################################ U.S. Geological Survey ############################### Geologic Hazards Team, MS966 ############################## PO Box 25046 #############################/############################## ############################/############################### Denver, Colorado 80225-0046 ################################ Phone: (303) 273-8596 ################################## Fax: (303) 273-8600 ################################### lahr@........ ##################################### http://giseis.alaska.edu/lahr http://lahr.org/john-jan Ian writes: The magic line of QB for serial i/o is: OPEN "COM1:19200,N,8,2,CS,DS,RB64000,TB10240" FOR RANDOM AS #1 obviously in this case, 19200 baud, no parity, 8 bits data, 2 stop bits. _____________________________________________________________________ Public Seismic Network Mailing List (PSN-L) From: GeE777@....... Subject: Re: QB serial AD input Date: Fri, 23 Oct 1998 12:55:23 EDT Hi I'll just add my two bits here. I use Vernier Software Multipurpose Lab Interface Program for Windows. It includes a interface board, MPLI Connector Box & test leads. I built a preamp much like they show on page 53 of their instruction manual and added an anti-aliasing filter. The Hardware has 3 inputs thus is suited for three component recording. They are located at- Vernier Software 8565 S. W. Beverton-Hillsdale Hwy Portland, Oregon 97225-2429 Phone (503) 297-5317 Fax (503) 297-1760 George Erich Seismic Exploration Consultant P. O. Box 2011, Norwalk, CA 90650, U. S. A. Phone (562) 868-6013 e-mail GeE777@....... 33 53.90N 118 04.53W In a message dated 10/23/98 9:32:26 AM Pacific Daylight Time, lahr@.................. writes: << I'm interested in using the serial input for a portable display of a geophone for educational purposes. Basically the computer is just used as an oscilloscope. >> _____________________________________________________________________ Public Seismic Network Mailing List (PSN-L) From: meredith lamb Subject: From (UFO) Teleseisms Control...?? Date: Fri, 23 Oct 1998 10:58:17 -0600 S-T Morrissey wrote: > (by the way, did someone turn off > the teleseisms greater than M=6 again?). Yes....I did it. I'am still looking for some "advertisers" for the PSN Trading Post deal, and well...I haven't seen hide nor hair of anything from anybody yet. So......this means all of you people are being forced under denial of any more teleseisms.... till some of you cough up some material for sale/trade or want; too me. Sorry......but thats the law of the wild west. Occasionally I might turn it on again to test some of my junkque here, but..... remember every time its teleseismically quiet, that I need some more stuff, to stuff, the understuffed list....ha. If this goes on long enough, I might even have to get back to my concrete stepping stone idea for a seismometer base....and come out with a lengthy, rambling, unqualified and meaningless message on the results. Shudder!! (Are you motivated now?) Hmm..... some of you might even want to read it?? Besides....my seismometers also need the long period seismic exercise too. I'am getting tired of binking the masses with my (UFO) tektite, to see if they still work. I now return control of your email to you.....or.....beam me back to earth..... Meredith Lamb, the PSN Trading Post spam man _____________________________________________________________________ Public Seismic Network Mailing List (PSN-L) From: Ian Smith Subject: Re: QB serial AD input Date: Fri, 23 Oct 1998 09:13:18 -1000 Hi, I'm actually using something completely non-standard (in this group). It's an old cast-off Omega standalone DAQ. You plug it in, it has it's own cpu(8086!), you send it commands over the serial interface and it sends back data. 12 bits, 16 channels etc. The advantage is it takes the load off the pc (the daq can also do things like mean multiple samples and the timing), the disadvantage is it's something else to leave switched on (fire hazard). I know you can get pcmcia a/d cards, if your portable display is on a laptop then that would be a solution, I just can't remember who sells them at the moment. You can obviously get modern versions of what I have, http://www.omega.com/products/prodlist.html is one web page of interest. I've never played with Visual Basic, so I don't know if the code for serial i/o will look like the QB one. I use mathcad for non-realtime but digitally filtered data display. cheers Ian Smith _____________________________________________________________________ Public Seismic Network Mailing List (PSN-L) From: lahr@.................. Subject: Re: QB serial AD input Date: Fri, 23 Oct 1998 13:28:30 -0600 (MDT) Ian, Thanks for the extra details. I'll check out Omega's page. I'm interested in a very inexpensive AD that attaches to either the serial or parallel ports and a program in Visual Basic to display the trace. I have one called LPT1 that connects to the parallel port. It consists of only one chip on a board inside the the parallel port plug. However, I don't have any source code to go with it. JCLahr _____________________________________________________________________ Public Seismic Network Mailing List (PSN-L) From: Greg Subject: Re: QB serial AD input Date: Fri, 23 Oct 1998 19:40:11 +0000 Ian Smith wrote: > something else to leave switched on (fire hazard). I know you can get > pcmcia a/d cards, if your portable display is on a laptop then that would be > a solution, I just can't remember who sells them at the moment. Of course none of these would work with SDR but, he just wanted a computer oscope. There are the serial port DI-150RS and USB port models at DATAQ : http://www.dataq.com/ I found a couple PCMCIA models at : http://www.adac.com/background/navigate.html#PIB Some PCMCIA boards at : http://www.keithley.com/ also. ,Greg _____________________________________________________________________ Public Seismic Network Mailing List (PSN-L) From: Gregory Bajuk Subject: Re: QB serial AD input Date: Fri, 23 Oct 1998 16:03:46 -0700 (PDT) I received the DATAQ Instruments serial port a/d waveform recording system last week and it is excellent. The internet special price of $49.95 includes serial hookup cable, The DI-150RS A/D module(exact same as radio shack is selling for $99.95) the recording/display/analysis software, a thermistor for temperature measurement, and full documentation and use manual. It is a two channel system. One nice feature is that you can change channel amplification with the click of the mouse, and it has a times 100 amplification feature. I hooked up a vertical magnet, spring coil arrangement and recorded footsteps 20 feet away with no external amplifier. The system was easily measuring disturbances at the millivolt level without external amplification. Anyway its a cheap way to record signals without installing a card in your computer. Greg Bajuk On Fri, 23 Oct 1998 lahr@.................. wrote: > > Ian, > > Which serial AD are you using? I'm interested in using the > serial input for a portable display of a geophone for > educational purposes. Basically the computer is just used > as an oscilloscope. > > What sets the sampling rate? > > Would this same code work with Visual Basic? > > Thanks, > JCLahr > ################################## John C. Lahr > ################################# Seismologist > ################################ U.S. Geological Survey > ############################### Geologic Hazards Team, MS966 > ############################## PO Box 25046 > #############################/############################## > ############################/############################### > Denver, Colorado 80225-0046 ################################ > Phone: (303) 273-8596 ################################## > Fax: (303) 273-8600 ################################### > lahr@........ ##################################### > http://giseis.alaska.edu/lahr > http://lahr.org/john-jan > > Ian writes: > > The magic line of QB for serial i/o is: > > OPEN "COM1:19200,N,8,2,CS,DS,RB64000,TB10240" FOR RANDOM AS #1 > > obviously in this case, 19200 baud, no parity, 8 bits data, 2 stop bits. > > _____________________________________________________________________ > > Public Seismic Network Mailing List (PSN-L) > > To leave this list email listserver@............. with the body of the > message: leave PSN-L > _____________________________________________________________________ Public Seismic Network Mailing List (PSN-L) From: "Rex Klopfenstein, Jr." Subject: VBB Oscillator Circuit Date: Fri, 23 Oct 1998 20:24:47 -0400 I have just posted my revised circuits of Sean Morrissey's circuit on on my web page. I have wired it as shown and it appears to work. -- Rex Klopfenstein, Jr. Bowling Green, OH rklopfen@......... http://www.wcnet.org/~rklopfen _____________________________________________________________________ Public Seismic Network Mailing List (PSN-L) From: Ian Smith Subject: Re: QB serial AD input Date: Fri, 23 Oct 1998 15:23:37 -1000 Gregory Bajuk wrote: > I received the DATAQ Instruments serial port a/d waveform recording system > It looks quite exciting. Do you know if the software runs on NT? I downloaded http://www.dataq.com/upgrade/wdqcemps.exe to see what the software looked like, but got an error message saying that the software was not for my machine type. What does the noise level look like on the sampled waveform? Presumably the rs232 "power lines" are filtered to remove the digital noise from the pc(?). Thanks for alerting me to that. cheers Ian smith _____________________________________________________________________ Public Seismic Network Mailing List (PSN-L) From: S-T Morrissey Subject: Re: VBB Oscillator Circuit Date: Fri, 23 Oct 1998 21:20:44 -0500 (CDT) Rex, You beat me to it; I was going to wait until next week. So I just now scanned my revisions of both the VRDT oscillator and the VRDT amplifier/demodulator to: http://www.eas.slu.edu/People/STMorrissey/index.html (to the figures.... page) I'm sure that the parts list you have made will be of great help; do you intend to fill it out with source and price info? I am still working on the demodulator noise problem, but I doubt that I can improve it much more. The displacement noise is now about 0.1 nanometers in the 10hz to 10 second range, increasing as expected with the period ( ie. 1/f noise). Regards, Sean-Thomas _____________________________________________________________________ Public Seismic Network Mailing List (PSN-L) From: Pete Subject: Re: QB serial AD input Date: Fri, 23 Oct 1998 23:23:27 -0700 Ian, I use the DI150RS, it works well and the noise appears to be low. They do have an NT version. The viewer software is very powerful! Pete Fleming Ian Smith wrote: > Gregory Bajuk wrote: > > > I received the DATAQ Instruments serial port a/d waveform recording system > > > > It looks quite exciting. Do you know if the software runs on NT? I > downloaded http://www.dataq.com/upgrade/wdqcemps.exe to see what the > software looked like, but got an error message saying that the software was > not for my machine type. > > What does the noise level look like on the sampled waveform? Presumably the > rs232 "power lines" are filtered to remove the digital noise from the pc(?). > > Thanks for alerting me to that. > > cheers > > Ian smith > > _____________________________________________________________________ > > Public Seismic Network Mailing List (PSN-L) > > To leave this list email listserver@............. with the body of the > message: leave PSN-L _____________________________________________________________________ Public Seismic Network Mailing List (PSN-L) From: "Rex Klopfenstein, Jr." Subject: Re: VBB Oscillator Circuit Date: Sat, 24 Oct 1998 09:58:39 -0400 This is not a bad idea! People might be able to find better prices. I will attempt to post a spreadsheet with prices and sources I used. S-T Morrissey wrote: > > do you intend to fill it out with source and price info? > -- Rex Klopfenstein, Jr. Bowling Green, OH rklopfen@......... www.wcnet.org/~rklopfen _____________________________________________________________________ Public Seismic Network Mailing List (PSN-L) From: "Francesco" Subject: WINQUAKE GIF FORMAT Date: Sat, 24 Oct 1998 18:45:32 +0100 I have a serious problem using winquake. When save the file in gif = format, the program communicates this error: "error making gif image: = unsupported bits/pixel =3D 32." I use a pc pentium 350 with video resolution of 600X800, but the same = thing also happens with a pentium 133 with small resolution; not, with a = Ibm Think Pad notebook . Does nobody have had the same problem? Thank you for the help. Francesco - I.E.S.N. PSN Italy

I have a serious problem using = winquake. When=20 save the file in gif format, the program communicates this error: =20 "error making gif image: unsupported bits/pixel =3D = 32."
 
I use a pc pentium 350 with video=20 resolution  of 600X800, but the same thing also happens with a = pentium 133=20 with small resolution; not, with a Ibm Think Pad=20 notebook .
 
Does nobody have had the same=20 problem?
 
Thank you for the help.
 
Francesco  -  I.E.S.N. PSN = Italy
From: Greg Subject: Re: WINQUAKE GIF FORMAT Date: Sat, 24 Oct 1998 11:32:01 -0700 > Francesco wrote: > > I have a serious problem using winquake. When save the file in gif > format, the program communicates this error: "error making gif image: > unsupported bits/pixel = 32." I just tried to make an image in Winquake 2.5.2 32bit. My screen is set to 1024x768x32bits/pixel. I used copy while an event was on the screen and the image moved to the clipboard. I then pasted it into another program which made a jpeg from it. It worked. Then I tried to save as gif 600x800 and it gave me your error message. So a workaround would be the above until Larry fixes it, I guess. For Larry: I have a an old PCI 4 Meg Matrox Millenium. This is under Windows 95. Let me know if you want me to try it at a lower color depth. ,Greg _____________________________________________________________________ Public Seismic Network Mailing List (PSN-L) From: Ted Blank Subject: Re: Oh good grief...QB serial i/o Date: Sat, 24 Oct 1998 18:33:24 -0700 (PDT) Thanks, Ian. Ted Blank San Jose, California On Thu, 22 Oct 1998, Ian & Liz wrote: > Hi, > > the magic line of QB for serial i/o is: > > OPEN "COM1:19200,N,8,2,CS,DS,RB64000,TB10240" FOR RANDOM AS #1 > > obviously in this case, 19200 baud, no parity, 8 bits data, 2 stop bits. > > CS and DS are important, they tell the port not to hardware handshake. Without > them it will try to handshake with the connected device, and chances are those > lines of the serial cable won't even be connected, causing the port to lock, and > giving the appearance of being dead. > > RB and TB specify the size of the i/o buffers. Very useful for data taking as data > will still buffer (at interrupt level) when the pc is busy doing other things (in > most cases). > > If your system still appears to be dead then swap pins 2 and 3 on the 25 way D type > connector. These are the Rx/Tx lines, and may be the wrong way round. Swap them > back if that doesn't work and think again. > > It seems to be a law of physics that 1: it takes a minimum of 2 hours to get a > serial line to work, 2: once working, never go wrong! > > Hope that helps. > > cheers > > Ian Smith > > > > > > _____________________________________________________________________ > > Public Seismic Network Mailing List (PSN-L) > > To leave this list email listserver@............. with the body of the > message: leave PSN-L > _____________________________________________________________________ Public Seismic Network Mailing List (PSN-L) From: Larry Cochrane Subject: Re: WINQUAKE GIF FORMAT Date: Sat, 24 Oct 1998 22:31:42 -0700 At 06:45 PM 10/24/98 +0100, Franceso wrote: >>>> I have a serious problem using winquake. When save the file in gif format, the program communicates this error: "error making gif image: unsupported bits/pixel = 32." I use a pc pentium 350 with video resolution of 600X800, but the same thing also happens with a pentium 133 with small resolution; not, with a Ibm Think Pad notebook . Does nobody have had the same problem? Thank you for the help. Francesco - I.E.S.N. PSN Italy <<<<<<<< This is a problem with the GIF "C" function library I'm using. It only handles 16 color, 256 color and I think 65K color modes. You probably have your system set for "True Color" mode. You can either change the number of bits per pixels, using the Display settings in the Control panel, to either 256 colors or maybe 65k colors. Or you can use the systems clipboard and transfer the bitmap image to another program like LView Pro and save the image as a GIF file from there. In WinQuake you use the View / Copy menu items to copy the image to the clipboard. -Larry Cochrane Redwood City, PSN _____________________________________________________________________ Public Seismic Network Mailing List (PSN-L) From: Larry Cochrane Subject: Re: SDR and amps and such Date: Sun, 25 Oct 1998 00:28:38 -0700 At 05:27 PM 10/22/98 +0000, Greg wrote: >I finally got my ADC card in my computer. Nothing is connected yet. I >plan on playing with WWV this weekend and maybe an unamplified geophone. >I was playing with the new SDR 2.5 last night and I pressed "E" to make >it record an event. The question I have is, how do I go from the raw >data file to an event file? The raw data is recorded as a file, but >Winquake won't show it in the file window. I changed the directory, but >appearantly it ignores everything that's not an event file. Maybe you >can do it with SDR? > There are two file types involved with SDR. One is the daily record file(s). This contains all of the data (samples) from each channel and is not readable by WinQuake. SDR uses these files, a new one is created each day, too create PSN formatted event files that WinQuake can read. Event files are created when the system is triggered from an event, using the replay feature (the "r" key), or pressing the "E" key to force an event file(s). Event files show up in a directory based on the root directory supplied by the "Event File(s) Dir:" setting under the F5 settings and the year and month (YYMM). An event file this month would show up in the directory \root\9810\. If you network your data logging system and your main computer you can set up SDR so that your event files show up on your main computer system. This way you won't need to use floppies to transfer event files. You do need to keep two systems running all the time for this too work...See the documentation for more info. >I'm still flipping coins on an amplifier. I have at least four choices >now. > >1. Get Larry's amp. I like the idea of just giving him some more money >and getting an amp that works quickly, but I'd like to burry the thing >eventually. Larry's amp requires a power line. Unless I put it inside of >all kinds of conduit and pipes and boxes, there's a fire hazard. > >2. Try and make one like Sean-Thomas uses. I have to have the board laid >out and manufactured. Then I have to buy all of the components and >solder them in. As I've mentioned before, I can't solder very well. > >3. Try and make a simpler one like >http://met.univnorthco.edu/resource/amp.htm >Similar problems with #2. I don't know enough about electronics so the >qualities are a bit of an unknown. The parts are only about $20 though. > >4. Talk to some really generous local electronics student and try and >get them to design one for me. For a small fee of course. Students can >mess things up and take a long time. An EE would cost too much almost >certainly. > >So I guess I need some oppinions. I might remind you that I'll be >connecting to a geophone. When I have a little more room, I might finish >my Lehman and connect it up. This is what I would do... First; try running the cable from the sensors into the house and have the amp / filter card there. Geophones are fairly low impedance and high output voltage so it maybe able to drive the cable without having to place the amp / filter outside. Maybe with some good quality cable, and if the length isn't to long, you might be able to get away with this. If this does'nt work, I would place the amp near the sensor, but not burry it. The few feet of wire, unless you can burry the sensor very deep, between the sensor and the amp will not effect things. Too power the amp, you could run 3 more wires (or two wire + shield cable) and have the AC power transformer inside. The amp board requires a center tapped 24 to 26 volt VAC transformer to power it. This low voltage should be safe to run between the house and the amp card. You could also place two fuses at the transformer end. Another way to power the board is to use a dc to dc converter located in the box with the amp. This could take +5 or +12 volts in, from a wall mounted dc power supply inside the house, and supply the need +- 15 to +- 20 volts needed to power the on board +-12 volt power regulators. The converter would need 400ma (or more) of output current. This way you would only need to run two more wires, or a single coax wire to power the board. A note about water proofing.. A friend of a friend once said about placing electronic equipment in a water tight box. "Do whatever you can too keep the water out. Then drill a hole at the lowest point of the box so that the water can run out". -Larry Cochrane Redwood City, PSN _____________________________________________________________________ Public Seismic Network Mailing List (PSN-L) From: Karl Cunningham Subject: Re: SDR and amps and such Date: Sun, 25 Oct 1998 07:53:32 -0800 At 12:28 AM 10/25/98 -0700, Larry wrote: >A note about water proofing.. A friend of a friend once said about placing >electronic equipment in a water tight box. "Do whatever you can too keep >the water out. Then drill a hole at the lowest point of the box so that the >water can run out". My $.02 here: Put a bag of dessicant inside the "waterproof" enclosure. Otherwise you may get condensation when it cools off, and with the voltages present you'll get electrolysis that will quickly ruin the board. Take the dessicant out once in a while and bake it in the oven at low temp for a while to dry it out, then put it back in. Karl Cunningham La Mesa, CA. PSN Station #40 karlc@....... _____________________________________________________________________ Public Seismic Network Mailing List (PSN-L) From: barry lotz Subject: Re: Barometric floats and flat springs Date: Sun, 25 Oct 1998 13:47:15 -0800 Brett et al Does anyone know what the change in modulus of spring steel vs temp might be ? Regards, Barry Brett Nordgren wrote: > snip--- > In Shanley, "Strength of Materials" he describes five characteristics of > the Modulus of Elasticity. Number 4 is: "The modulus of elasticity > decreases with increasing temperature - This can be explained by atomic > theory, but for engineering purposes the value of E is best determined > experimentally at the desired temperature". > snip--- _____________________________________________________________________ Public Seismic Network Mailing List (PSN-L) From: Brett Nordgren Subject: Re: Barometric floats and flat springs Date: Sun, 25 Oct 1998 17:22:32 -0500 Barry, The only number I've ever seen was one Bob Barns quoted from a book, that he posted last Wednesday. Since E itself is very similar among different varieties of steel, it wouldn't surprise me if the tempco of E was also pretty similar. From R. Barns: > The following quote is from "The >Science of Clocks & Watches" by AL Rawlings, 3rd., ed., 1993. (Fascinating >reading for those interested in mechanical devices.).............. ............................ > "But E for steel also varies with temp., for the material becomes more >yielding as it gets warmer. It has been found that at normal temps. E >decreases about 240 ppm/deg C. This will make the period of vibration >longer and the watch will lose from the effect of heat on the hairspring." .......................... If anyone comes up with a good source on the subject, I would be very interested, too Regards, Brett At 01:47 PM 10/25/98 -0800, you wrote: >Brett et al > Does anyone know what the change in modulus of spring steel vs temp might >be ? > >Regards, > Barry > _____________________________________________________________________ Public Seismic Network Mailing List (PSN-L) From: barry lotz Subject: Re: Barometric floats and flat springs Date: Sun, 25 Oct 1998 15:07:14 -0800 Brett After I posted the question I went back to my college books and found a reference in Elements of Material Science by Van Vlack, Addison Wesley 1966. He references: A.G.Guy,Elements of Physical Metallurgy, Addison Wessley 1959. The graph shows the modulus of iron,copper,& aluminum vs temp. The approx slope for iron is -0.007E6/degree C. This is more than what Robert had said (- .000240/degree C.). You might try to calculate the position change with both to see. Regards Barry Brett Nordgren wrote: > Barry, > > The only number I've ever seen was one Bob Barns quoted from a book, that > he posted last Wednesday. > Since E itself is very similar among different varieties of steel, it > wouldn't surprise me if the tempco of E was also pretty similar. > > >From R. Barns: > > > The following quote is from "The > >Science of Clocks & Watches" by AL Rawlings, 3rd., ed., 1993. (Fascinating > >reading for those interested in mechanical devices.).............. > ........................... > > "But E for steel also varies with temp., for the material becomes more > >yielding as it gets warmer. It has been found that at normal temps. E > >decreases about 240 ppm/deg C. This will make the period of vibration > >longer and the watch will lose from the effect of heat on the hairspring." > ......................... > > If anyone comes up with a good source on the subject, I would be very > interested, too > > Regards, > > Brett > _____________________________________________________________________ Public Seismic Network Mailing List (PSN-L) From: Brett Nordgren Subject: Re: Barometric floats and flat springs Date: Sun, 25 Oct 1998 19:00:52 -0500 Barry, As I calculate it -0.007E6 per degree C out of 29E6 (typical value of E for steel) is roughly -241 ppm/degree C. That's close enough to Bob's number for me. Data point #2! Brett At 03:07 PM 10/25/98 -0800, you wrote: >Brett > After I posted the question I went back to my college books and found a >reference in Elements of Material Science by Van Vlack, Addison Wesley 1966. He >references: A.G.Guy,Elements of Physical Metallurgy, Addison Wessley 1959. The >graph shows the modulus of iron,copper,& aluminum vs temp. The approx slope for >iron is -0.007E6/degree C. This is more than what Robert had said (- >.000240/degree >C.). You might try to calculate the position change with both to see. > Regards _____________________________________________________________________ Public Seismic Network Mailing List (PSN-L) From: "Rex Klopfenstein, Jr." Subject: Bridge Amp/Demodulator Question Date: Sun, 25 Oct 1998 20:45:16 -0500 Sean I have just printed out your modified bridge amplifier/demodulator circuit. I have one question. It is in the area of opamps A2 and A3. Am I right to assume that the inputs to these opamps (via 10K resistors) come from each phase of the output transformer located in the oscillator circuit? -- Rex Klopfenstein, Jr. Bowling Green, OH rklopfen@......... www.wcnet.org/~rklopfen _____________________________________________________________________ Public Seismic Network Mailing List (PSN-L) From: barry lotz Subject: Re: Barometric floats and flat springs Date: Sun, 25 Oct 1998 17:50:42 -0800 Brett I appreciate the clarification on how Bob was representating the change in E w/ temp. I reviewed your spring files and came up with the following: Using the STM8 operating point line in your STM-8 spring analysis table as a start. If we now keep the force the same (assuming gravity doesn't change) and vary K**2 to take into account a change of E(so I don't have to calculate the integral). I then interpolated to find a new gap opening for a change in K**2 equal 29.007/29. I came up with a gap change of 0.0035"/degree C or a force of 0.55 gms to return the spring to the original position. Seems reasonable Sean Thomas. regards Barry Brett Nordgren wrote: > Barry, > > As I calculate it -0.007E6 per degree C out of 29E6 (typical value of E for > steel) is roughly -241 ppm/degree C. That's close enough to Bob's number > for me. Data point #2! > > Brett > _____________________________________________________________________ Public Seismic Network Mailing List (PSN-L) From: S-T Morrissey Subject: Re: Bridge Amp/Demodulator Question Date: Mon, 26 Oct 1998 19:48:30 -0600 (CST) Rex, That is correct. The references to pin 6 and pin 7 at the input to the switch drivers is the same as shown at the left of the drawing, with ph (phase) 1 and phase 2, which are the two outputs of the transformer of the oscillator. Connected this way eliminates the phase jitter of the previous cascaded amplifiers/inverter. There are still a few minor adaptations for a VRDT rather than a tiltmeter, like the calibrate resistors: I need to come up with an estimate, which will be something like 3 ohms = 4 microns. The secondary gain loops of A1 and A5 (the variable resistor) do not seem to be necessary with the VRDT. The gain of A6 is set with 2.2megs in the feedback to about 5.5 to get 250 millivolts/micron. I also just re-scanned the two drawings, using the "B&W drawing" settings rather than the B&W photo mode, which produced a rather poor result last Friday. You should find them more readable. Also, regarding the noise study, I found that to push it below the 1 nanometer level (from 10 hz to 10 seconds), a good shielded box is necessary around the electronics, as well as a very clean +,- 9V DC power supply. I substituted a pair of 9-volt batteries to evaluate the power supply noise by comparison. regards, Sean-Thomas _____________________________________________________________________ Public Seismic Network Mailing List (PSN-L) From: Clark Wockner Subject: neis quake notice Date: Mon, 26 Oct 1998 20:20:36 -0600 HI All: Has anyone gotten a notice from the NEIC lately. I think I may have been dropped from the list server. Clark _____________________________________________________________________ Public Seismic Network Mailing List (PSN-L) From: Seisguy@....... Subject: Re: neis quake notice Date: Mon, 26 Oct 1998 21:28:16 EST The last one I got was for the M3.3 Virginia event last week. Mike _____________________________________________________________________ Public Seismic Network Mailing List (PSN-L) From: S-T Morrissey Subject: Re: neis quake notice Date: Tue, 27 Oct 1998 00:52:18 -0600 (CST) Someone turned off the teleseisms, unless Meredith's Inter-Gallactic Seismometer is channeling them into his mega-magnetic drive and is going to release them all on halloween. In the mean time, NEIS hasn't had much to report. Regards, Sean-Thomas _____________________________________________________________________ Public Seismic Network Mailing List (PSN-L) From: Gregory Bajuk Subject: Dataq Instruments free software update Date: Mon, 26 Oct 1998 23:04:37 -0800 (PST) Dataq Instruments www.dataq.com has just issued an update to its free WinDaq/Lite waveform acquisition, recording, analysis software. The update includes the capability to trigger waveform recording at a specified level, and to continue recording for a specified time or number of samples after the trigger event has occurred. ie. record for one hour after an event is triggered for example, and then stop recording until the next event is triggered. This trigger/record feature can be used with the DI-150RS serial port A/D module that is available as an Internet special for 49.95. (same as the Radio Shack model which sells for 99.99). The nice thing about this system is that it is powered from the serial port, has adjustable gain of 1 or 100, 2 channels, and is sensitive to millivolt or below signals. I hooked it up directly to my simple vertical sensor (5000 ft of magnet wire wound around a plastic peanut butter jar, a 20 oz speaker magnet suspended inside the jar from a spring-1.5 sec mechanical period- and damped by covering the magnet with antifreeze.) It can detect footsteps 20 ft away without using an external amplifier. The sensor puts out more than +- .7 volts if I move the magnet by hand. The WinDaq software (Win95/98/3.1/NT versions) displays data acquisition continuously in real time, while recording or not, and the recorded file can be reviewed in real time. Nice feature since only one computer and one program running is needed. You can keep the computer and acquisition program running continuously and turn off the monitor when not using it. This module uses a Pic 16C54A-04/P Microcontroller and has a 12 bit A/D for conversion. Overall its a great system for getting started in earthquake data recording and the price is right especially with the new triggered feature. Greg Bajuk _____________________________________________________________________ Public Seismic Network Mailing List (PSN-L) From: Greg Subject: Re: Dataq Instruments free software update Date: Tue, 27 Oct 1998 17:32:13 +0000 Gregory Bajuk wrote: > This trigger/record feature can be used with the DI-150RS serial port > A/D module that is available as an Internet special for 49.95. (same as > the Radio Shack model which sells for 99.99). When I called them to order the Internet Special, the salesman said that the model number is the DI-150SP. The DI-150RS is still about $100. The difference is the DI-150SP has some kind of offset or drift problem at the highest internal gain setting. Maybe he was wrong if you're having such good results? I already bought Larry's 16-bit board anyway. Speaking of buying stuff... I've got someone hunting for geophones right now. He found some used untested 4.5 Hz models for about $25. Probably not including shipping. Let me know if you're interested and I can return his address. I have him looking for lower frequency models right now. I have my 10 Hz geophone hitched up without an amp or filter and the noise is huge. Here's an odd bit. I put the geophone on top of the SDR computer and the noise was lower than when I put it on my old Lehman prototype base. The base has long wood screws that go into the carpet a lot more than the flat bottom of the running computer. You'd think that the computer would be a lot noisier. Also when the geophone was on top of the computer you could see what was happening in the room a lot better. Now it doesn't show up or is buried in noise? The next step is trying it out on the tile floor. Then I'll need to buy an amp/filter. ,Greg _____________________________________________________________________ Public Seismic Network Mailing List (PSN-L) From: Ian Smith Subject: Re: Dataq Instruments free software update Date: Tue, 27 Oct 1998 08:21:12 -1000 Hi, I'm looking for a couple of geophones, I'd appreciate the info on them. Thanks Ian Smith > Speaking of buying stuff... I've got someone hunting for geophones right > now. He found some used untested 4.5 Hz models for about $25. Probably > not including shipping. Let me know if you're interested and I can > return his address. I have him looking for lower frequency models right > now. _____________________________________________________________________ Public Seismic Network Mailing List (PSN-L) From: Ian Smith Subject: Re: Dataq Instruments free software update Date: Tue, 27 Oct 1998 08:49:03 -1000 Greg wrote: > I have my 10 Hz geophone hitched up without an amp or filter and the > noise is huge. Here's an odd bit. I put the geophone on top of the SDR > computer and the noise was lower than when I put it on my old Lehman > prototype base. The base has long wood screws that go into the carpet a > lot more than the flat bottom of the running computer. You'd think that > the computer would be a lot noisier. Also when the geophone was on top > of the computer you could see what was happening in the room a lot > better. Now it doesn't show up or is buried in noise? The next step is > trying it out on the tile floor. Then I'll need to buy an amp/filter. I had a similar experience. Not being an expert in emf etc I didn't solve it, but it seemed to me that the metal base of the seismograph was acting as an attenna. I encased the sensor lead in a Faraday cage (cooke box and aluminium foil!), and that made it worse! Perhaps there is an emf expert in our midst who could explain? cheers Ian Smith _____________________________________________________________________ Public Seismic Network Mailing List (PSN-L) From: Gregory Bajuk Subject: Re: Dataq Instruments free software update Date: Tue, 27 Oct 1998 16:53:24 -0800 (PST) Not True. The internet special delivers the DI-150RS module. When you click on the internet special (which says DI-150SP) the page that comes up shows the DI-150RS information. When talking to the sales rep he verified that I would be getting the RS model if I ordered it. I put in an order and received the RS model. Greg Bajuk On Tue, 27 Oct 1998, Greg wrote: > Gregory Bajuk wrote: > > > This trigger/record feature can be used with the DI-150RS serial port > > A/D module that is available as an Internet special for 49.95. (same as > > the Radio Shack model which sells for 99.99). > > When I called them to order the Internet Special, the salesman said that > the model number is the DI-150SP. The DI-150RS is still about $100. The > difference is the DI-150SP has some kind of offset or drift problem at > the highest internal gain setting. Maybe he was wrong if you're having > such good results? > > I already bought Larry's 16-bit board anyway. > > Speaking of buying stuff... I've got someone hunting for geophones right > now. He found some used untested 4.5 Hz models for about $25. Probably > not including shipping. Let me know if you're interested and I can > return his address. I have him looking for lower frequency models right > now. > > I have my 10 Hz geophone hitched up without an amp or filter and the > noise is huge. Here's an odd bit. I put the geophone on top of the SDR > computer and the noise was lower than when I put it on my old Lehman > prototype base. The base has long wood screws that go into the carpet a > lot more than the flat bottom of the running computer. You'd think that > the computer would be a lot noisier. Also when the geophone was on top > of the computer you could see what was happening in the room a lot > better. Now it doesn't show up or is buried in noise? The next step is > trying it out on the tile floor. Then I'll need to buy an amp/filter. > > ,Greg > > _____________________________________________________________________ > > Public Seismic Network Mailing List (PSN-L) > > To leave this list email listserver@............. with the body of the > message: leave PSN-L > _____________________________________________________________________ Public Seismic Network Mailing List (PSN-L) From: Edward Cranswick Subject: Re: VBB Oscillator Circuit Date: Tue, 27 Oct 1998 18:15:50 -0700 Rex- Did you record, feel, or otherwise sense the Pymatuning EQ? Where is Bowling Green, OH? (and where is Ed the Cat?) -Edward Rex Klopfenstein, Jr. wrote: > I have just posted my revised circuits of Sean Morrissey's circuit on on > my web page. I have wired it as shown and it appears to work. > > -- > Rex Klopfenstein, Jr. > Bowling Green, OH > rklopfen@......... > http://www.wcnet.org/~rklopfen > > _____________________________________________________________________ > > Public Seismic Network Mailing List (PSN-L) > > To leave this list email listserver@............. with the body of the > message: leave PSN-L -- Edward Cranswick Tel: 303-273-8609 US Geological Survey, MS 966 Fax: 303-273-8600 PO Box 25046, Federal Center cranswick@........ Denver, CO 80225-0046 USA E.M. Forster said, "Only connect". _____________________________________________________________________ Public Seismic Network Mailing List (PSN-L) From: Doug Crice Subject: Re: Dataq Instruments free software update Date: Tue, 27 Oct 1998 13:26:50 -0800 Geophones with natural frequencies lower than say 20 Hz only work properly when they are right side up (depending on which way is up for a particular geophone). If you turn one sideways, they still work but the signal is a lot smaller (and lacks the low frequencies) -- Doug Crice web site http://www.georadar.com GeoRadar Inc. e-mail dcrice@............ 19623 Via Escuela Drive phone 408-867-3792 Saratoga, CA 95070 USA fax 408-867-4900 _____________________________________________________________________ Public Seismic Network Mailing List (PSN-L) From: Edward Cranswick Subject: AGU Participation of HIGH SCHOOL STUDENTS at AGU meetings Date: Tue, 27 Oct 1998 18:40:18 -0700 Catherine- I think that if AGU wants to send the message to high school students that they should check out the Earth sciences, then it does not make sense to charge these students so much to attend and participate in an AGU meeting that they have to first either get an NSF grant or sell dope on the side to support their science habit. Do you have any advice about how else we can convince AGU to allow high school students to attend and participate in AGU meetings at a price they can afford? I, for one, would be willing to make a special contribution in my annual AGU dues for high school students, much as we already do with AGU support for minorities. -Edward > Subject: > Re: I know you're there > Date: > Tue, 27 Oct 1998 08:41:44 -0800 (PST) > From: > Ted Blank > To: > Edward Cranswick > > > > > Hi, yes here in spirit...we are just starting a "Quake Trackers" club at > the school. 10 kids signed up, so I would expect that about half of them > would be interested in the poster session. The teacher is very > supportive, at least that's a plus. However he's been very busy, and a > friend has been in the hospital so it's been pretty crazy. I read your > notes about joining the AGU and then registering. What would that mean > in terms of $$$ for the kids? $300 was just unthinkable. Thanks. > > > Ted Blank > San Jose, California > > On Sat, 24 Oct 1998, Edward Cranswick wrote: > > > Ted- > > What is the staus of your PSN presentation? How many students do you > > anticipate will participate? > > -Edward > > > > -- > > Edward Cranswick Tel: 303-273-8609 > > US Geological Survey, MS 966 Fax: 303-273-8600 > > PO Box 25046, Federal Center cranswick@........ > > Denver, CO 80225-0046 USA E.M. Forster said, "Only connect". > > > > > > > Catherine Johnson wrote: > Dear Ed, > > Here's the reply from AGU. The most $-effective option > is for the students to become AGU members and then they > can register as undergrads. Please let me know the names > of people who will be doing this so that I can pass the > info onto Frank Ireton at AGU in case there are any problems. > > Best regards, > > Catherine > > >From: FIreton@....... > >Date: Wed, 21 Oct 1998 09:49 -0400 (EDT) > >Subject: Students at the AGU meeting. > >To: catherine@........ > >MIME-version: 1.0 > >Status: > > > > Catherine, > > > > Sorry for the delay getting back to you. We had to get approval from > > Fred. He said that if they will join AGU they can register as > > undergraduate students. That will be a significant saving over > > member's registration prices. That information can be found on the AGU > > home page. Please keep me posted on the outcome. > > > > Frank > > > > ----------------------------------------- > Dr. Catherine Johnson > Education and Outreach Program Manager > IRIS > 1200, New York Ave., #800 > Washington DC 20005 > > Tel: (202) 682 2220 > Fax: (202) 682 2444 > Email: catherine@........ > Web: http://www.iris.washington.edu/EandO > Personal web page: http://magellan.ciw.edu > ----------------------------------------- -- Edward Cranswick Tel: 303-273-8609 US Geological Survey, MS 966 Fax: 303-273-8600 PO Box 25046, Federal Center cranswick@........ Denver, CO 80225-0046 USA E.M. Forster said, "Only connect". _____________________________________________________________________ Public Seismic Network Mailing List (PSN-L) From: S-T Morrissey Subject: geophone sensitivity Date: Tue, 27 Oct 1998 19:55:53 -0600 (CST) Most geophones are made in both vertical and horizontal configurations; the difference being in how the upper suspension is configured. You can sometimes find an H stamped on the case of a horizontal. You can also tell which is which by shaking it and listening for the coil to hit the stops. A vertical will hit both stops as it is shaken vertically along the axis of the instrument; obviously a horizontal needs to be moved horizontally for the same effect. As the frequency response is increased, the geophone is much more tolerant of tilt, as Doug pointed out. For the Geospace HS series, all the phones above 15 hz can operate with 90 degrees of tilt, while the 4.5 hz has a max of 15deg, and the 10hz has a max of 30deg.. For longer periods, like the 1hz L4-C, the tilt angle directly affects the natural period. Regards, Sean-Thomas _____________________________________________________________________ Public Seismic Network Mailing List (PSN-L) From: "Rex Klopfenstein, Jr." Subject: Re: VBB Oscillator Circuit Date: Tue, 27 Oct 1998 21:34:59 -0500 I don't know of anybody that felt the quake in the Bowling Green area. Several people I know who work in Toledo (about 20 miles north) felt the quake. They also work in large building that most likely amplified the tremor. Over the years I can't remember feeling the one or two large (for Ohio) quakes. Maybe this is because we are located in an old swamp (Black Swamp) that was formed when the glacier retreated. The old swamp was filled with gravel retreating glacier and later with sand from an ancient lake. Ed the Cat is an old, overweight cat whose only goal in life is to sleep and eat! About the only thing in nature that gets his attention is when a thunderstorm approaches, he's under the bed for the duration!! Edward Cranswick wrote: > Did you record, feel, or otherwise sense the Pymatuning EQ? Where is > Bowling Green, OH? (and where is Ed the Cat?) > -Edward -- Rex Klopfenstein, Jr. Bowling Green, OH rklopfen@......... www.wcnet.org/~rklopfen _____________________________________________________________________ Public Seismic Network Mailing List (PSN-L) From: Edward Cranswick Subject: Re: High school student participation at AGU Date: Tue, 27 Oct 1998 20:24:32 -0700 CARRJJ- Would you please tell me the URL of that NASA website. Thank you. -Edward CARRJJ@....... wrote: > There is also Project Inspire for high school student. It hunts for spherics > and whistlers (natural radio signals). Bill Pine at Chaffey High School in > Ontario, CA is the director. They can be found on the NASA web site. > > _____________________________________________________________________ > > Public Seismic Network Mailing List (PSN-L) > > To leave this list email listserver@............. with the body of the > message: leave PSN-L -- Edward Cranswick Tel: 303-273-8609 US Geological Survey, MS 966 Fax: 303-273-8600 PO Box 25046, Federal Center cranswick@........ Denver, CO 80225-0046 USA E.M. Forster said, "Only connect". _____________________________________________________________________ Public Seismic Network Mailing List (PSN-L) From: Norman Davis WB6SHI Subject: Re: Dataq Instruments free software update Date: Tue, 27 Oct 1998 20:10:11 At 11:04 PM 10/26/98 -0800, you wrote: >Dataq Instruments www.dataq.com has just issued an update to >its free WinDaq/Lite waveform acquisition, recording, analysis software. >The update includes the capability to trigger waveform recording at a >specified level, and to continue recording for a specified time or number >of samples after the trigger event has occurred. ie. record for one hour >after an event is triggered for example, and then stop recording until the >next event is triggered. Greg I and another fellow over hear near sacramento has been using the di-150rs for some time now and I did send a message to windaq about adding this feature to the software. They came through rather quickly with the added change. Now my question is, how do you get it to record. I downloaded the new software and installed it and it works like the old one did. I checked trigger storage but it doesn't ask for a file name. I turned on recording but it seems to record all the time just as it did before. Norman Davis WB6SHI Shingle Springs, Ca normd@............. http://www.directcon.net/normd/index.htm _____________________________________________________________________ Public Seismic Network Mailing List (PSN-L) From: GeE777@....... Subject: Re: geophone sensitivity Date: Wed, 28 Oct 1998 06:49:29 EST Hi All, The vertical geophone is much more tolerant of tilt than the horizonial phones are. As phones are tilted, the coil does not rest in the center of its travel area and the output becomes less linear. I have a patent on using two vertical geophones placed 45 degrees from vertical in opposite directions, that is 90 degrees from each other. By adding these geophone outputs, one gets vertical traveling waves. Subtract one from the other one gets H (Shear) waves. I think there is an error in the statement below. Tilting a vertical geophone 90 degrees will not work as the coil will be hitting the top stop when at rest. Same with tilting a horizontal phone 90 degrees, the coil will rest on the stop. In a message dated 10/27/98 5:57:33 PM Pacific Standard Time, sean@........... writes: << As the frequency response is increased, the geophone is much more tolerant of tilt, as Doug pointed out. For the Geospace HS series, all the phones above 15 hz can operate with 90 degrees of tilt, while the 4.5 hz has a max of 15deg, and the 10hz has a max of 30deg.. >> George Erich Seismic Exploration Consultant P. O. Box 2011, Norwalk, CA 90650, U. S. A. Phone (562) 868-6013 e-mail GeE777@....... 33 53.90N 118 04.53W _____________________________________________________________________ Public Seismic Network Mailing List (PSN-L) From: Jim Hannon Subject: Re: High school student participation at AGU Date: Wed, 28 Oct 1998 06:08:14 -0600 Edward Cranswick wrote: > > CARRJJ- > Would you please tell me the URL of that NASA website. > Thank you. > -Edward > http://ssdoo.gsfc.nasa.gov/education/inspire/inspire.html Is the Inspire site. -- Jim Hannon http://soli.inav.net/~jmhannon/ 42,11.90N 91,39.26W WB0TXL _____________________________________________________________________ Public Seismic Network Mailing List (PSN-L) From: Brett Nordgren Subject: New web site - Leaf springs, etc. Date: Wed, 28 Oct 1998 10:20:27 -0500 To all, I've been slowly proceeding with some more number-crunching on the STM-8 and on feedback instruments in general. Have made a somewhat improved version of the leaf-spring analysis spreadsheet, as well as some other stuff. To simplify the process of sharing these files, I've put up a very small, relatively private, Web site from which you can review or download my files, at: http://members.home.net/nordgren/public/ Downloads are via your Web browser's file-transfer system. Direct anonymous ftp doesn't appear to be allowed. I am hoping that by sharing some of this work, I'll be able to discover my errors more quickly and perhaps get some new ideas. Please let me know where you think there are problems, either with the data or with the Web page. Many of the files are in .pdf form. If .rtf is better, please let me know and I'll add that where I can. Since I am hoping to update this every few days, if you're interested, please check back often. Brett Nordgren _____________________________________________________________________ Public Seismic Network Mailing List (PSN-L) From: John Lahr Subject: Re: Dataq Instruments free software update Date: Wed, 28 Oct 1998 09:11:45 -0700 (MST) I just ordered the Dataq DI-150SP and the salesman said that this unit had a larger offset (drift?) than the DI-150RS unit. In all other respects it is the same and will run the same software. For my needs for a "table-top seismology demo" I don't expect that the offset will not be a problem. JCLahr ################################## John C. Lahr ################################# Seismologist ################################ U.S. Geological Survey ############################### Geologic Hazards Team, MS966 ############################## PO Box 25046 #############################/############################## ############################/############################### Denver, Colorado 80225-0046 ################################ Phone: (303) 273-8596 ################################## Fax: (303) 273-8600 ################################### lahr@........ ##################################### http://giseis.alaska.edu/lahr http://lahr.org/john-jan _____________________________________________________________________ Public Seismic Network Mailing List (PSN-L) From: S-T Morrissey Subject: geophone tilting Date: Wed, 28 Oct 1998 11:38:59 -0600 (CST) George: Re: tilting geophones: The statements I posted are correct, since the data was taken directly from the data sheet for the Geospace HS-1-LT geophones. We are using these phones for a number of experiments to broaden the response. I could scan the sheet, but it would not be legible. Of course the specs are different for Mark Products and others, and I have not dug them out. It can be observed that as the natural period of the geophone is made shorter or the frequency higher, like greater than than 15 hz, the suspension becomes more rigid or less compliant, so the change in force from gravity on the suspension from vertical to horizontal is not enough to cause the coil to travel to its stops. Conversely, a longer period or lower frequency phone has a very "soft" or compliant suspension, and the coil will travel to the stops with little change in the amount of g that results from tilting. For a horizontal phone, the tilt tolerance is much less than for the vertical because of this, as would be expected. Reading from the data sheet: the maximum tilt angle for a 4.5hz vertical is 15deg, horizontal is +,- 2.5deg; at 7.5hz: vertical 20deg, horiz: +,- 3.5deg; 10hz: vertical 30deg; horiz: +,- 7.5 deg. For the 15, 20,and 28hz geophones, the maximum tilt for "All Models" (quoting the sheet) is "+,- 90 degrees". Perhaps you have not seen of these specifications. I can mail a copy. These LT (long travel) phones have a minimum peak-peak travel of 5.1mm. This applies to all the models. OF course, other phones will have different specifications, so the user should be aware of them. Regards, Sean-Thomas _____________________________________________________________________ Public Seismic Network Mailing List (PSN-L) From: Gregory Bajuk Subject: Re: Dataq Instruments free software update Date: Wed, 28 Oct 1998 10:03:22 -0800 (PST) John, let us know if you receive the SP or RS version. I ordered the internet special (SP was on the web site) but when I talked to the salesman I pointed out that the information page about the SP showed the information on the RS module, and told him I wanted the RS module since that is what they advertised. They sent me the RS module. By the way you can null offset thru software. connect a jumper wire between Ch1 and ground and then do a low cal on that channel setting that to 0.00 volts. Do the same to Ch2. Save the settings as Default in the Edit menu. Greg Bajuk On Wed, 28 Oct 1998, John Lahr wrote: > > I just ordered the Dataq DI-150SP and the salesman said that this > unit had a larger offset (drift?) than the DI-150RS unit. In all > other respects it is the same and will run the same software. For > my needs for a "table-top seismology demo" I don't expect that the > offset will not be a problem. > > JCLahr > ################################## John C. Lahr > ################################# Seismologist > ################################ U.S. Geological Survey > ############################### Geologic Hazards Team, MS966 > ############################## PO Box 25046 > #############################/############################## > ############################/############################### > Denver, Colorado 80225-0046 ################################ > Phone: (303) 273-8596 ################################## > Fax: (303) 273-8600 ################################### > lahr@........ ##################################### > http://giseis.alaska.edu/lahr > http://lahr.org/john-jan > > > > _____________________________________________________________________ > > Public Seismic Network Mailing List (PSN-L) > > To leave this list email listserver@............. with the body of the > message: leave PSN-L > _____________________________________________________________________ Public Seismic Network Mailing List (PSN-L) From: Karl Cunningham Subject: Re: New web site - Leaf springs, etc. Date: Wed, 28 Oct 1998 10:27:24 -0800 Brett -- Very concise, detailed analysis of feedback systems. Thank you for generating and posting it. Since you've asked for comments, I have a couple of very minor ones regarding the following paragraph taken from your feedback-systems analysis: You wrote: >>>> Physical considerations dictate that as frequency is increased, a frequency will eventually be reached where the magnitude of the loop gain A(s)B(s) has fallen to unity. That frequency is called the gain-crossover frequency. If, at the gain-crossover frequency, the phase shift in A(s)B(s) has lagged by 180 deg (or more) from the initial 180 deg. associated with the negative polarity of the feedback, the system will oscillate. <<<< I like to express one of the points slightly differently: If the phase shift of the feedback reaches 180 degrees while the loop gain is above unity, the system will oscillate. Also, the system will oscillate at 180 degrees of either leading or lagging phase shift. Thank you for doing all this work. I am very anxious to see what you come up with regarding the STM-8 feedback system. I am particularly curious how the various terms of the equation are derived, with respect to the hardware. A more thorough understanding of the relationship of the hardware and feedback equations will help those of us who don't have ideal VBB hardware and would like to adjust things to try to make the equations work with what we have. Thanks again, Karl Cunningham La Mesa, CA. PSN station #40 karlc@....... _____________________________________________________________________ Public Seismic Network Mailing List (PSN-L) From: Doug Crice Subject: Re: geophone sensitivity Date: Wed, 28 Oct 1998 08:18:41 -0800 Sean is correct, sensitivity to tilt is a function of natural frequency. To get geophones to resonate at higher frequencies, you make the springs stiff. When you make the springs stronger, they can hold up the mass better against gravity. While there are non-linearities related to getting the moving coil off center, the real change comes when the coil runs up against the mechanical stops. Geophones with a high resonant frequency will even operate upside down. Low frequency geophones have soft springs, because relatively low restoring force is part of the natural frequency equation. They bottom out with small amounts of tilt. -- Doug Crice web site http://www.georadar.com GeoRadar Inc. e-mail dcrice@............ 19623 Via Escuela Drive phone 408-867-3792 Saratoga, CA 95070 USA fax 408-867-4900 _____________________________________________________________________ Public Seismic Network Mailing List (PSN-L) From: Karl Cunningham Subject: Re: Dataq Instruments free software update Date: Wed, 28 Oct 1998 10:34:08 -0800 For what it's worth, I ordered the "Internet Special" from Dataq Instruments about three weeks ago and got the DI-150RS model. Haven't done any temperature testing, but it doesn't seem to drift much just sitting on the bench. Karl Cunningham La Mesa, CA. PSN station #40 karlc@....... At 10:03 AM 10/28/98 -0800, Greg Bajuk wrote: >John, let us know if you receive the SP or RS version. I ordered the >internet special (SP was on the web site) but when I talked to the >salesman I pointed out that the information page about the SP showed the >information on the RS module, and told him I wanted the RS module since >that is what they advertised. They sent me the RS module. By the way you >can null offset thru software. connect a jumper wire between Ch1 and >ground and then do a low cal on that channel setting that to 0.00 volts. >Do the same to Ch2. Save the settings as Default in the Edit menu. _____________________________________________________________________ Public Seismic Network Mailing List (PSN-L) From: Gregory Bajuk Subject: Re: Dataq Instruments free software update Date: Wed, 28 Oct 1998 10:48:13 -0800 (PST) Norman, first you might check to see that you downloaded the right version as the DATAQ web site has a couple of places which list software for download. Once on the home page www.dataq.com select Software Updates, then go down thru the table of software list to the entry- WinDaq/Lite(including WWB) 11 Sep 98- and download this file. When you are initially setting up a channel for recording (Set-Up) mode you select several parameters such as Channel, sample rate, low and high cal, Channel gain and measurement range, and selecting, Option, enable trigger mode(then set trigger levels and number of post trigger samples-set enough post trigger samples to correspond to a time. ie maybe a half-hour to an hour to insure you will record the whole event) Next go to File, and choose set as Default. This saves all your Set-up information as default and prevents you from recording a channel using some previous Set-up settings. Now before recording open a NEW file and then choose Record from the File menu. The Record mode will be displayed at the bottom of the screen and have an asterisk next to it. When the trigger level is exceeded the asterick will disappear and recording to disk starts. Recording will continue as long as the number of samples(time) you selected when setting up the trigger mode. I used the thermocouple input to test the trigger level feature. Once the file is recorded it can be reviewed and manipulated using the Dataq waveform browser software. Also file exporting to disk allows nine diferent modes( including ASCII, binary, spreadsheet, ASYST, DADiSP,CALC, NSoft Dac). I hope one of these formats can be easily converted for use in Larry Cockrane' PSN event format so that these files can be used with WINQuake. Also, I will keep working with DATAQ to see if they can expand the trigger features to be more like that available in SDR. Perhaps those on the list who have DATAQ products could do the same. Greg Bajuk On Tue, 27 Oct 1998, Norman Davis WB6SHI wrote: > At 11:04 PM 10/26/98 -0800, you wrote: > >Dataq Instruments www.dataq.com has just issued an update to > >its free WinDaq/Lite waveform acquisition, recording, analysis software. > >The update includes the capability to trigger waveform recording at a > >specified level, and to continue recording for a specified time or number > >of samples after the trigger event has occurred. ie. record for one hour > >after an event is triggered for example, and then stop recording until the > >next event is triggered. > > Greg > I and another fellow over hear near sacramento has been using the > di-150rs for some time now and I did send a message to windaq about adding > this feature to the software. They came through rather quickly with the > added change. Now my question is, how do you get it to record. I downloaded > the new software and installed it and it works like the old one did. I > checked trigger storage but it doesn't ask for a file name. I turned on > recording but it seems to record all the time just as it did before. > > > Norman Davis WB6SHI > Shingle Springs, Ca > normd@............. > http://www.directcon.net/normd/index.htm > > > _____________________________________________________________________ > > Public Seismic Network Mailing List (PSN-L) > > To leave this list email listserver@............. with the body of the > message: leave PSN-L > _____________________________________________________________________ Public Seismic Network Mailing List (PSN-L) From: Brett Nordgren Subject: Re: New web site - Leaf springs, etc. Date: Wed, 28 Oct 1998 14:06:54 -0500 Karl, Many thanks for the kind comments and suggestions. > >I like to express one of the points slightly differently: If the phase >shift of the feedback reaches 180 degrees while the loop gain is above >unity, the system will oscillate. Let me think about this one. I'm going to try to find a counter-example of such a loop that is stable. (if I can) > >Also, the system will oscillate at 180 degrees of either leading or lagging >phase shift. > I absolutely agree. I'm just used to working with loops where you're fighting the lagging phase due to a loop gain function that falls with rising frequency. Brett _____________________________________________________________________ Public Seismic Network Mailing List (PSN-L) From: John Lahr Subject: Re: Dataq Instruments SP vs RS Date: Wed, 28 Oct 1998 12:22:54 -0700 (MST) I just spoke to John at Dataq about the SP vs RS confusion. Apparently they only make one model, which is labeled DI-150RS. If the unit has more than 30 mv offset on the 100 mv range, then it is sold for half price as a DI-150SP (without changing the labeling etc.) JCLahr ################################## John C. Lahr ################################# Seismologist ################################ U.S. Geological Survey ############################### Geologic Hazards Team, MS966 ############################## PO Box 25046 #############################/############################## ############################/############################### Denver, Colorado 80225-0046 ################################ Phone: (303) 273-8596 ################################## Fax: (303) 273-8600 ################################### lahr@........ ##################################### http://giseis.alaska.edu/lahr http://lahr.org/john-jan _____________________________________________________________________ Public Seismic Network Mailing List (PSN-L) From: Edward Cranswick Subject: Re: Dataq Instruments free software update Date: Wed, 28 Oct 1998 14:38:33 -0700 DataQ Enthusiasts- In late 1993 or early 1994, about the time of the Northridge EQ, I purchased a "sample" DataQ A/D board and software for $50. It was 12-bit, single channel, and connected to the serial port. I believe (or maybe to the parallel port). Tom Bice here at USGS, Golden, rigged up a nice little pre-amp for it and the necessary cabling, etc., to connect it to a 4.5 Hz vertical geophone. Altogether, with its software, it worked very nicely, displaying traces in realtime in either DOS or Windows 3.1 and recording timeseries to a disk file, but I don't believe it had an trigger capability. Steve Hammond and I were going to use it as part of our PSN/highschool project, and I demonstrated it and left it with him in August 1994. However, what with the demands of the Northridge EQ study and the vicissitudes of the Silicon Valley economy and public school system, we never got further with the project. However, it was a simple and straightforward piece of hardware/software that worked well, and the recent correspondence about DataQ reminded me of it. -Edward Gregory Bajuk wrote: > Dataq Instruments www.dataq.com has just issued an update to > its free WinDaq/Lite waveform acquisition, recording, analysis software. > The update includes the capability to trigger waveform recording at a > specified level, and to continue recording for a specified time or number > of samples after the trigger event has occurred. ie. record for one hour > after an event is triggered for example, and then stop recording until the > next event is triggered. > > This trigger/record feature can be used with the DI-150RS serial port > A/D module that is available as an Internet special for 49.95. (same as > the Radio Shack model which sells for 99.99). > > The nice thing about this system is that it is powered from the serial > port, has adjustable gain of 1 or 100, 2 channels, and is sensitive to > millivolt or below signals. I hooked it up directly to my simple vertical > sensor (5000 ft of magnet wire wound around a plastic peanut butter jar, a > 20 oz speaker magnet suspended inside the jar from a spring-1.5 sec > mechanical period- and damped by covering the magnet with antifreeze.) It > can detect footsteps 20 ft away without using an external amplifier. The > sensor puts out more than +- .7 volts if I move the magnet by > hand. > > The WinDaq software (Win95/98/3.1/NT versions) displays data acquisition > continuously in real time, while recording or not, and the recorded file > can be reviewed in real time. Nice feature since only one computer and > one program running is needed. You can keep the computer and acquisition > program running continuously and turn off the monitor when not using it. > > This module uses a Pic 16C54A-04/P Microcontroller and has a 12 bit A/D > for conversion. > > Overall its a great system for getting started in earthquake data > recording and the price is right especially with the new triggered > feature. > > Greg Bajuk > > _____________________________________________________________________ > > Public Seismic Network Mailing List (PSN-L) > > To leave this list email listserver@............. with the body of the > message: leave PSN-L -- Edward Cranswick Tel: 303-273-8609 US Geological Survey, MS 966 Fax: 303-273-8600 PO Box 25046, Federal Center cranswick@........ Denver, CO 80225-0046 USA E.M. Forster said, "Only connect". _____________________________________________________________________ Public Seismic Network Mailing List (PSN-L) From: "Francesco" Subject: EVENT IT'S COMING Date: Wed, 28 Oct 1998 22:45:26 +0100 LARGE SURFACE WAVE IT'S COMING NOW - NO P START HERE AT 22.39 SOMEONE HAVE THE SAME REGISTRATION? I.E.S.N. PSN ITALY STATION: OSIMO, 43.290N 13.294E FRANCESCO
LARGE SURFACE WAVE IT'S COMING = NOW  - =20 NO P
START HERE  AT = 22.39
SOMEONE HAVE THE SAME=20 REGISTRATION? 
 
I.E.S.N. PSN ITALY
STATION:  OSIMO,  43.290N  = 13.294E
 
FRANCESCO
From: "Francesco" Subject: EVENT IN PROGRESS Date: Wed, 28 Oct 1998 23:04:03 +0100 22.38 UTC M ~4 LOC: BALKAN REGION I.E.S.N. PSN ITALY
22.38  UTC
M ~4
LOC: BALKAN REGION
 
I.E.S.N.   PSN = ITALY
From: johnccole@........ (john c cole) Subject: Re: EVENT IN PROGRESS Date: Wed, 28 Oct 1998 20:22:36 -0600 What is the latitude and longitude of the Balkan ? quake recorded at 22:38 UTC 28/10/98 ? Event recorded in Pearland, Texas at ~5:38 PM local time. ___________________________________________________________________ You don't need to buy Internet access to use free Internet e-mail. Get completely free e-mail from Juno at http://www.juno.com/getjuno.html or call Juno at (800) 654-JUNO [654-5866] _____________________________________________________________________ Public Seismic Network Mailing List (PSN-L) From: Norman Davis WB6SHI Subject: Re: Dataq Instruments free software update Date: Wed, 28 Oct 1998 18:43:53 At 10:48 AM 10/28/98 -0800, you wrote: >Norman, first you might check to see that you downloaded the right version >as the DATAQ web site has a couple of places which list software for >download. Once on the home page www.dataq.com select Software >Updates, then go down thru the table of software list to the entry- >WinDaq/Lite(including WWB) 11 Sep 98- and download this file. Ok did this. >When you are initially setting up a channel for recording (Set-Up) mode >you select several parameters such as Channel, sample rate, low and high >cal, Channel gain and measurement range, and selecting, Option, enable >trigger mode(then set trigger levels and number of post trigger I can't find a "trigger mode". I see the refference to trigger mode in the help screens but don't see it in the options. I see trigger storage but no trigger mode. >samples-set enough post trigger samples to correspond to a time. ie maybe >a half-hour to an hour to insure you will record the whole event) I see that when I have the trigger storage checked. > >Next go to File, and choose set as Default. This saves all your Set-up >information as default and prevents you from recording a channel using >some previous Set-up settings. Now before recording open a NEW file and >then choose Record from the File menu. The Record mode will be displayed >at the bottom of the screen and have an asterisk next to it. When the >trigger level is exceeded the asterick will disappear and recording to >disk starts. Recording will continue as long as the number of >samples(time) you selected when setting up the trigger mode. I see the record on the bottom but no asterisk next to it. I have the trigger set at one volt and the input is will below that. I would think that would be high enough to keep it from triggering. could you send me one of your recorded files and I will load as a reference file and see how you have yours set. Norm Norman Davis WB6SHI Shingle Springs, Ca normd@............. http://www.directcon.net/normd/index.htm _____________________________________________________________________ Public Seismic Network Mailing List (PSN-L) From: johnccole@........ (john c cole) Subject: Re: EVENT IN PROGRESS Date: Wed, 28 Oct 1998 20:43:23 -0600 Francesco, I recorded the same seismic event as you recorded at approximately the same time. I do not have my AD card installed in my computer as of yet. When I do I will have accurate time. apparently we are the only two to record the event so far. My latitude and longitude is 29,33',14"N 95,33',47"W. Let me know what else that you find. John C. Cole ___________________________________________________________________ You don't need to buy Internet access to use free Internet e-mail. Get completely free e-mail from Juno at http://www.juno.com/getjuno.html or call Juno at (800) 654-JUNO [654-5866] _____________________________________________________________________ Public Seismic Network Mailing List (PSN-L) From: Edward Cranswick Subject: Re: AGU Participation of HIGH SCHOOL STUDENTS at AGU meetings Date: Wed, 28 Oct 1998 20:45:27 -0700 Catherine- I thank you very much for your thorough and comprehensive response to my question about fees for high school students to attend the December AGU meeting. There was confusion in my mind and the minds of some PSN members about what the price is, and you have cleared that up. I think that $22 per student is a good deal in the short-term, and I will push to have the students register ASAP, i.e., before the Nov 6 deadline. I look foward to further developments in AGU programs for high school students. I thank you very much again for your charming and effective assistance in clearing this matter up, even if much of the diffficulty was my own confusion. -Edward Catherine Johnson wrote: > Hi Edward, > > OK, maybe there is some confusion regarding the per student cost > for attending AGU. The annual membership fee for a student (they will > need a signature from a teacher at their school) is $7. > I understood the email from Frank Ireton to read that Fred Spilhaus > says that if the kids join AGU as students (thereby receiving weekly > EOS and monthly Physics today - probably enough to make them > go sell dope and not be Earth Scientists anyway!) they can > register for the AGU meeting as undergrad students. The pre-registration > deadline is Nov 6. Before Nov 6 the cost is $15 for one day, $30 for more > than 1 day; after Nov 6 these #s are $25 and $40 respectively. > So the total per kid cost could be as low as $22 (1-day only at > meeting and register before end of next week) or as high as $47 (more > than 1 day at meeting and register after Nov 6). I'd have > thought 1 day at the meeting is enough (it is for me!!!!)? > > So total for 10 kids is $220. > > Maybe this is what Ted figured but it seemed to me from the > emails that maybe he thought it was hundreds of $s per child? > > Fortunately I have so far led a life shielded from the inner > workings of AGU (until a couple of weeks ago when I first > went to an AGU committee meeting). I can tell you from my > limited experience that $22/person is in AGU's eyes a "deal". > I know that Frank Ireton and others have pushed for a long > time to get even the undergrad registration fee approved. > Outreach and education below the college level is starting > to take off but it will still be some time before there > is a groundswell of support within predominantly research > depts and therefore within AGU for it. There are some tremendous > individuals working really hard for this to happen and it > will but it takes time. The real issue within the research > community is there is NO appreciation of the lack of funds > available at the K-12 level. To the research community > $220 for 10 kids is a give-away, they have no understanding > of how difficult it is to raise even a couple of hundred > dollars for a class project / trip / whatever. You probably > know all this anyway, and I'm not endorsing it, just trying > to explain why I think things will change but will take > time. > > I'll definitely promote your idea of membership fees for > scientists including a small amount that would support > high school students attending AGU meetings or such like. > I think that's a good idea and I'll bring it up at the > next committee meeting I have to go to (Committee on Education > and Human Resources-CEHR). > > Can you let me know whether there was confusion regarding the > per child $ amount or not, and whether the $s are still too > much? I can't do anything about it that would make any > difference for this year, and as a single individual I > probably can't change the inner crankings of AGU anyway but > I can at least get the CEHR committee to talk about it and make > a recommendation for the future. > > Best regards, > Catherine > > ----------------------------------------- > Dr. Catherine Johnson > Education and Outreach Program Manager > IRIS > 1200, New York Ave., #800 > Washington DC 20005 > > Tel: (202) 682 2220 > Fax: (202) 682 2444 > Email: catherine@........ > Web: http://www.iris.washington.edu/EandO > Personal web page: http://magellan.ciw.edu > ----------------------------------------- -- Edward Cranswick Tel: 303-273-8609 US Geological Survey, MS 966 Fax: 303-273-8600 PO Box 25046, Federal Center cranswick@........ Denver, CO 80225-0046 USA E.M. Forster said, "Only connect". _____________________________________________________________________ Public Seismic Network Mailing List (PSN-L) From: Edward Cranswick Subject: Registering the students Date: Wed, 28 Oct 1998 22:33:05 -0700 Ted & Jan- Catherine Johnson of IRIS has straightened me out (see excerpt of email from her below) about what is involved for the students to participate in the poster that you and Jan will present (U42A-27: "Seismic Monitoring in the Classroom - A Complement to the Traditional Middle School Earth Science Curriculum") at the San Francisco AGU meeting at 1:30 PM on Thursday afternoon on 10 December. Please email me a list of the students who will participate in your poster presentation as soon as possible, preferably tomorrow and definitely by Friday. Each student must fill out three hardcopy forms -- 1) registration; 2) membership application; 3) student certification -- that are available from the Web: http://earth.agu.org/meetings/fm98rgpr.html http://earth.agu.org/inside/memprintable.html http://earth.agu.org/inside/memapprove.html and which must also be signed by a teacher and then be faxed to AGU accompanied by payment of the fees. If the students have their registration forms completed and submitted by the Nov 6 deadline, I will pay the registration fee of $22 per student with my American Express card (I hope I can solve the problem of having to sign each form) -- if the there is a delay and we must pay the higher rate of $32, everything will become much more involved and problematic. I hope that your situation has calmed down a bit. Please let me know that you have received this email. -Edward > OK, maybe there is some confusion regarding the per student cost > for attending AGU. The annual membership fee for a student (they will > need a signature from a teacher at their school) is $7. > I understood the email from Frank Ireton to read that Fred Spilhaus > says that if the kids join AGU as students (thereby receiving weekly > EOS and monthly Physics today - probably enough to make them > go sell dope and not be Earth Scientists anyway!) they can > register for the AGU meeting as undergrad students. The pre-registration > deadline is Nov 6. Before Nov 6 the cost is $15 for one day, $30 for more > than 1 day; after Nov 6 these #s are $25 and $40 respectively. > So the total per kid cost could be as low as $22 (1-day only at > meeting and register before end of next week) or as high as $47 (more > than 1 day at meeting and register after Nov 6). I'd have > thought 1 day at the meeting is enough (it is for me!!!!)? > -- Edward Cranswick Tel: 303-273-8609 US Geological Survey, MS 966 Fax: 303-273-8600 PO Box 25046, Federal Center cranswick@........ Denver, CO 80225-0046 USA E.M. Forster said, "Only connect". _____________________________________________________________________ Public Seismic Network Mailing List (PSN-L) From: rayv Subject: Re: Dataq Instruments free software update Date: Wed, 28 Oct 1998 21:37:09 -0500 what may be happening is the magnet in the geophone is being attracted to the metal case of the computer and that is why it does not appear to have as much noise in the signal. At 05:32 PM 10/27/98 +0000, you wrote: >Gregory Bajuk wrote: > >> This trigger/record feature can be used with the DI-150RS serial port >> A/D module that is available as an Internet special for 49.95. (same as >> the Radio Shack model which sells for 99.99). > >When I called them to order the Internet Special, the salesman said that >the model number is the DI-150SP. The DI-150RS is still about $100. The >difference is the DI-150SP has some kind of offset or drift problem at >the highest internal gain setting. Maybe he was wrong if you're having >such good results? > >I already bought Larry's 16-bit board anyway. > >Speaking of buying stuff... I've got someone hunting for geophones right >now. He found some used untested 4.5 Hz models for about $25. Probably >not including shipping. Let me know if you're interested and I can >return his address. I have him looking for lower frequency models right >now. > >I have my 10 Hz geophone hitched up without an amp or filter and the >noise is huge. Here's an odd bit. I put the geophone on top of the SDR >computer and the noise was lower than when I put it on my old Lehman >prototype base. The base has long wood screws that go into the carpet a >lot more than the flat bottom of the running computer. You'd think that >the computer would be a lot noisier. Also when the geophone was on top >of the computer you could see what was happening in the room a lot >better. Now it doesn't show up or is buried in noise? The next step is >trying it out on the tile floor. Then I'll need to buy an amp/filter. > >,Greg > >_____________________________________________________________________ > >Public Seismic Network Mailing List (PSN-L) > >To leave this list email listserver@............. with the body of the >message: leave PSN-L > _____________________________________________________________________ Public Seismic Network Mailing List (PSN-L) From: Greg Subject: Re: Dat... geophone noise Date: Thu, 29 Oct 1998 17:23:18 +0000 rayv wrote: > > what may be happening is the magnet in the geophone is being attracted to > the metal case of the computer and that is why it does not appear to have > as much noise in the signal. I think you're right. I might have also been right about the carpet acting as an amplifier. The noise level on the computer is about +- 80, on the base on the carpet is about +- 120, and last night on the tile was probably closer to +- 200. I didn't record any blank events to check the values exactly and I turned off autosave or it would never stop. I think a filter and a lower freqeuncy geophone will help a lot. I got some PVC pipe and I've been debating to myself what to fill it with. The best thing I think I've come up with is filling it with sand and putting the geohpone wrapped in plastic in epoxy covering the sand. Or maybe aluminum foil? I know sand is supposed to be noisy outside, but as a weight in a sealed container, would it be noisy? Lead would be difficult, unless I just put a bunch of small fishing weights in there. I got at least 8 feet of pipe to play with, so there's room for error. Maybe I should be trying to cast a concrete mass on the outside of the PVC? That might be messier than inside. Just thinking outloud. Neat stuff though, Greg _____________________________________________________________________ Public Seismic Network Mailing List (PSN-L) From: Edward Cranswick Subject: [Fwd: Students at the AGU meeting.] Date: Thu, 29 Oct 1998 12:39:53 -0700 -- Edward Cranswick Tel: 303-273-8609 US Geological Survey, MS 966 Fax: 303-273-8600 PO Box 25046, Federal Center cranswick@........ Denver, CO 80225-0046 USA E.M. Forster said, "Only connect". Dear Frank, I know you're out of town at NSTA but I figured I'd just pass this info on as follow-up to my earlier email and as a pre-emptive strike against any possible confusion amongst the meeting registration folks at AGU. There will apparently be 10 students registering who are associated with the following abstract submitted by Ted Blank and Jan Froom U42A-27: "Seismic Monitoring in the Classroom - A Complement to the Traditional Middle School Earth Science Curriculum" I think the registration is being coordinated by Ed Cranswick of the USGS in Golden - he will likely submit the payment, though of course the students are filling out the necessary forms. Thanks for all your help with this. Catherine ----------------------------------------- Dr. Catherine Johnson Education and Outreach Program Manager IRIS 1200, New York Ave., #800 Washington DC 20005 Tel: (202) 682 2220 Fax: (202) 682 2444 Email: catherine@........ Web: http://www.iris.washington.edu/EandO Personal web page: http://magellan.ciw.edu ----------------------------------------- From: "Rex Klopfenstein, Jr." Subject: VBB Block Diagram Date: Thu, 29 Oct 1998 18:22:51 -0500 I have been looking over Sean's Block Diagram of the VBB. Is this basically a PID (proportional/integral/derivative) controller? Also, I see that there is a need for an integrator. I have looked through most of the books I have access to and the discussion of the integrator is somewhat limited. Can anybody point me to sources that have some indepth discussion of the construction of a real world integrator. Any help would be appreciated. -- Rex Klopfenstein, Jr. Bowling Green, OH rklopfen@......... www.wcnet.org/~rklopfen _____________________________________________________________________ Public Seismic Network Mailing List (PSN-L) From: S-T Morrissey Subject: VBB integrator Date: Thu, 29 Oct 1998 20:03:33 -0600 (CST) Rex, Re electronic integrators: I can only remark about them in the context of the VBB fedback seismometer. The point here is not to make an optimal integrator, but to satisfy the need of the transfer function, which needs a simple integral of the displacement voltage, with the phase response of a single pole. The integrator used in the triple feedback VBB seismometer uses an instrumentation or an operational amp of very good quality. It can be either a simple inverting configuration, with the capacitor as the feedback to the - input, and the input through a high value resistor, like 2 megohms. The time constant is R*C, or 2 megs * 20 microfarad is 40 seconds. The non-inverting input is grounded, preferably through a similar resistor. For the VBB feedback, since the signal cannot be inverted in the loop, I prefer to use a non-inverting or single pole low pass configuration. Here, the input is through the high value resistor to the + input, and the capacitor is from there to common. The feedback is to the - input through a similar resistor. I use the instrumentation amp (the classical 3 amplifier configuration) because I have a bunch of them on hand, and their high input impedance handles any DC leakage of the capacitors. On the other hand, a single amp like the LM308A or a OPA111 will do fine. It is desirable that the input offset voltage and the current noise be minimal. The OP-97 is an excellent combination of low offset, low noise, and low bias current and low power. The LT1012 is similar. For the capacitor, low leakage electrolytics are useable, (although some commercial units use a large box of polystyrene capacitors), and are connected + to + for a non-polarized performance (at half the value of either). TAG types are quite leaky and thermally unstable. Something that lists as a 5% tolerance is generally of good quality and will work well. These are also useful for the differential feedback capacitor, although non-polarized low-leakage values can be found in the range of this component. Regards, Sean-Thomas _____________________________________________________________________ Public Seismic Network Mailing List (PSN-L) From: Karl Cunningham Subject: Re: VBB integrator Date: Thu, 29 Oct 1998 20:09:17 -0800 At 08:03 PM 10/29/98 -0600, you wrote: >For the capacitor, low leakage electrolytics are useable, (although some >commercial units use a large box of polystyrene capacitors), and are connected >+ to + for a non-polarized performance (at half the value of either). >TAG types are quite leaky and thermally unstable. Something that lists >as a 5% tolerance is generally of good quality and will work well. >These are also useful for the differential feedback capacitor, although >non-polarized low-leakage values can be found in the range of this >component. Sean-Thomas' remarks brought something to mind. The temperature coefficient of capacitance of aluminum electrolytics is not very good. This ordinarily wouldn't make much difference since I don't think the value of the integrator capacitor needs to be held too precisely. But if the system is not mechancially zeroed (such as is the case when the spring is not exactly opposing gravity), a constant current through the coil is necessary to add the remaining force. In this case there is a voltage across the integrator capacitor, and a change in capacitance with temperature will result in a change in the voltage across the capacitor in order to maintain the same charge. This could introduce temperature-related drift in the output. Another thing of interest. With an RC integrator in the feedback, there needs to be steady-state voltage out of the displacement transducer to feed current to the voice coil to make up the difference between the spring and gravity. This results in an output offset proportional to this difference. With an op-amp type integrator (with the capacitor in the feedback), a steady-state voltage out of the displacement transducer (and hence the output) isn't needed -- the integrator op-amp supplies the needed current to the voice coil. There is a price to pay, however, which is another stage to do a signal inversion since the op-amp integrator is an inverting stage. Karl Cunningham La Mesa, CA. PSN Station #40 karlc@....... _____________________________________________________________________ Public Seismic Network Mailing List (PSN-L) From: "Frank Cooper" Subject: MY 1969 SEISMOGRAPH Date: Fri, 30 Oct 1998 18:03:39 -0600 In case anyone might be interested I have posted pictures of my 1969-74 = seismograph on my web site at http://freeweb.pdq.net/fxc/ Frank Cooper, Friendswood, Texas, USA
In case anyone might be interested I have posted = pictures of=20 my 1969-74 seismograph on my web site at http://freeweb.pdq.net/fxc/
 
Frank Cooper, Friendswood, Texas,=20 USA
From: barry lotz Subject: Kings Beach events Date: Fri, 30 Oct 1998 18:54:22 -0800 Well as luck would have it my power went out from 8:16-11:01 UTC and I missed the whole thing. I think that was the last straw I'm going to invest in a low power 386 SBC! To heck with PG&E. Regards Barry _____________________________________________________________________ Public Seismic Network Mailing List (PSN-L) From: "J. D. Cooley" Subject: WinQuake question Date: Fri, 30 Oct 1998 19:14:59 -0800 I realize, of course, that the x-axis is time, but what units are the y-axis in? TIA, "JD" _____________________________________________________________________ Public Seismic Network Mailing List (PSN-L) From: Karl Cunningham Subject: Re: WinQuake question Date: Fri, 30 Oct 1998 19:45:27 -0800 JD -- The Y axis is in A/D counts. On Larry's board, full scale is +/- 5 volts. If you have the 12-bit A/D, that's 2.44mV per count, or 152uV per count for the 16-bit A/D. Karl Cunningham La Mesa, CA. PSN Station #40 karlc@....... At 07:14 PM 10/30/98 -0800, you wrote: >I realize, of course, that the x-axis is time, but what units are the >y-axis in? _____________________________________________________________________ Public Seismic Network Mailing List (PSN-L) From: Edward Cranswick Subject: Re: MY 1969 SEISMOGRAPH Date: Fri, 30 Oct 1998 22:30:37 -0700 Frank- I got started in seismology in 1974 using portable analog seismographs called Big Drum recorders because they recorded on big drums wrapped with smoked paper using a sapphire stylus, but yours is the biggest drum I've seen. You have an incredible amount of patience to persist for three decades until you got your first seismogram!!! -Edward Frank Cooper wrote: > In case anyone might be interested I have posted pictures of my > 1969-74 seismograph on my web site at > http://freeweb.pdq.net/fxc/ Frank Cooper, Friendswood, Texas, USA -- Edward Cranswick Tel: 303-273-8609 US Geological Survey, MS 966 Fax: 303-273-8600 PO Box 25046, Federal Center cranswick@........ Denver, CO 80225-0046 USA E.M. Forster said, "Only connect". _____________________________________________________________________ Public Seismic Network Mailing List (PSN-L) From: Edward Cranswick Subject: Re: Kings Beach events Date: Fri, 30 Oct 1998 22:36:09 -0700 Barry- Ironically, we, the USGS, just received a grant from PGE of half a megabuck to install 40 strong motion instruments (Kinemetric K2s) in the Santa Clara Valley to study the effects of strong ground motions on their San Jose distribution. -Edward barry lotz wrote: > Well as luck would have it my power went out from 8:16-11:01 UTC and I > missed the whole thing. I think that was the last straw I'm going to > invest in a low power 386 SBC! To heck with PG&E. > > Regards > Barry > > _____________________________________________________________________ > > Public Seismic Network Mailing List (PSN-L) > > To leave this list email listserver@............. with the body of the > message: leave PSN-L -- Edward Cranswick Tel: 303-273-8609 US Geological Survey, MS 966 Fax: 303-273-8600 PO Box 25046, Federal Center cranswick@........ Denver, CO 80225-0046 USA E.M. Forster said, "Only connect". _____________________________________________________________________ Public Seismic Network Mailing List (PSN-L) From: meredith lamb Subject: Re: MY 1969 SEISMOGRAPH Date: Fri, 30 Oct 1998 22:23:34 -0700 Frank Cooper wrote: > In case anyone might be interested I have posted pictures of my > 1969-74 > > seismograph on my web site at http://freeweb.pdq.net/fxc/ Frank > Cooper, Friendswood, Texas, USA OOOHHHH does it bring back nostalgia for me. Trying to make things out of everyday items was itself a difficult thing to try. And of course even getting a magnet like that shown in the S.A. article was very difficult......and in a way, obtaining a equivalent magnet hasn't really changed in the sense of difficulty now. Betcha you enjoyed all the challenges that were a part of it. Meredith Lamb _____________________________________________________________________ Public Seismic Network Mailing List (PSN-L) From: Larry Cochrane Subject: Re: WinQuake question Date: Fri, 30 Oct 1998 23:14:31 -0800 JD, As Karl pointed out, the Y scale is in A/D counts. The reason WinQuake only displays A/D counts is because there is no information in the PSN event file that would let WinQuake know what the Y should be. Even if there was information in the event file for the Y scale, most of us don't know what our sensors are putting out....The only sensors I have with known output characteristics are my strong motion sensors. I have no idea what my Lehman and SG sensors output. The magnitude correction number (for a lack of a better term), used by WinQuake to determine ML and Ms magnitude, does give WinQuake some Y scale information. Station operators determine / calibrate the magnitude correction number by using known size events. The problem with this is the sensitivity of the system includes any local ground amplification or attenuation and is not a direct calibration of the sensor. -Larry Cochrane Redwood City, PSN At 07:45 PM 10/30/98 -0800, you wrote: >JD -- > >The Y axis is in A/D counts. On Larry's board, full scale is +/- 5 volts. >If you have the 12-bit A/D, that's 2.44mV per count, or 152uV per count for >the 16-bit A/D. > >Karl Cunningham >La Mesa, CA. >PSN Station #40 >karlc@....... > > >At 07:14 PM 10/30/98 -0800, you wrote: >>I realize, of course, that the x-axis is time, but what units are the >>y-axis in? > > >_____________________________________________________________________ > >Public Seismic Network Mailing List (PSN-L) > >To leave this list email listserver@............. with the body of the >message: leave PSN-L > _____________________________________________________________________ Public Seismic Network Mailing List (PSN-L) From: Larry Cochrane Subject: Re: Kings Beach events Date: Fri, 30 Oct 1998 23:34:50 -0800 I knew something interesting would happen... My system was also down, but I can't blame PG&E. For several years now I have needed a new roof for my house. I finally got around to getting one, so I needed to remove my antennas used to monitor some USGS sensors. I also needed to remove the wires between my sensors located in a spare bed room and my SDR system, since the wires where running over the roof. The roofer is almost done, so I should be back on line in a few days. -Larry Cochrane Redwood City, PSN At 06:54 PM 10/30/98 -0800, Barry wrote: >Well as luck would have it my power went out from 8:16-11:01 UTC and I >missed the whole thing. I think that was the last straw I'm going to >invest in a low power 386 SBC! To heck with PG&E. > >Regards > Barry > _____________________________________________________________________ Public Seismic Network Mailing List (PSN-L) From: "Erich F. Kern" Subject: Re: Kings Beach events Date: Sat, 31 Oct 1998 12:39:20 -0800 Larry, Have you thought of putting your antennas in the attic? I've got UHF-TV and scanner antennas in our attic with low noise broadband preamps at the antennas (no need to weatherproof anything) and get first rate reception from San Diego, 70 miles south of us, even on the high UHF (620 to 806 MHz) channels. The tile roof doesn't seem to have much if any attenuation. This wouldn't work if you have a flat roof and stucco exterior walls since the signal would have to "look" through the wire mesh embedded in the stucco. Cheers, Erich Kern -----Original Message----- From: Larry Cochrane To: PSN-L Mailing List Date: Friday, October 30, 1998 23:35 Subject: Re: Kings Beach events >I knew something interesting would happen... My system was also down, but I >can't blame PG&E. For several years now I have needed a new roof for my >house. I finally got around to getting one, so I needed to remove my >antennas used to monitor some USGS sensors. I also needed to remove the >wires between my sensors located in a spare bed room and my SDR system, >since the wires where running over the roof. > >The roofer is almost done, so I should be back on line in a few days. > >-Larry Cochrane >Redwood City, PSN > >At 06:54 PM 10/30/98 -0800, Barry wrote: >>Well as luck would have it my power went out from 8:16-11:01 UTC and I >>missed the whole thing. I think that was the last straw I'm going to >>invest in a low power 386 SBC! To heck with PG&E. >> >>Regards >> Barry >> > > >_____________________________________________________________________ > >Public Seismic Network Mailing List (PSN-L) > >To leave this list email listserver@............. with the body of the >message: leave PSN-L _____________________________________________________________________ Public Seismic Network Mailing List (PSN-L) From: CARRJJ@....... Subject: Re: Kings Beach events Date: Sat, 31 Oct 1998 16:12:02 EST I saw one fellow build a UHF antenna "radome" out of a plastic trash can. It was waterproof and provided good signal. Innovation...ain't it neat. Joe Carr _____________________________________________________________________ Public Seismic Network Mailing List (PSN-L) From: "Al Allworth" Subject: Test Date: Sat, 31 Oct 1998 22:00:31 -0800 Testing for return. _____________________________________________________________________ Public Seismic Network Mailing List (PSN-L) From: Arie Verveer Subject: Re: WinQuake question Date: Sun, 01 Nov 1998 14:55:32 +0800 Hi, Larry Cochrane wrote: > The magnitude correction number (for a lack of a better term), used by > WinQuake to determine ML and Ms magnitude, does give WinQuake some Y scale > information. Station operators determine / calibrate the magnitude > correction number by using known size events. The problem with this is the > sensitivity of the system includes any local ground amplification or > attenuation and is not a direct calibration of the sensor. > I found that the magnitude corrections (Ml & Ms) for the teleseismic and local events to be different. On my system the teleseismic events are 0.00013 and 0.0003 for the local events. The match between my recordings of the local events and the results published by the geophysical observatory are very close. From this, I have assumed that the S-G seismometer that uses larry's electronics is giving out displacement information. Would that be a correct assumption? Arie _____________________________________________________________________ Public Seismic Network Mailing List (PSN-L) From: GeE777@....... Subject: Re: geophone tilting Date: Sun, 1 Nov 1998 09:25:40 EST Sean; OK I haven't seen the specs on this geophone. I assumed it is much like most miniture and sub miniture geophones used in the exploration today. I'll call Geospace and get a data sheet. When I first started in seismic exploration in 1948 (wow!) the phones we had then were about 6 inches in diameter & had very stiff springs connected to one side of the coil & the spring worked like a hinge. This would not give a linear response good enough for todays exploration needs. They would work sideways, upside down, etc. In a message dated 10/28/98 9:40:50 AM Pacific Standard Time, sean@........... writes: << The statements I posted are correct, since the data was taken directly from the data sheet for the Geospace HS-1-LT geophones. >> _____________________________________________________________________ Public Seismic Network Mailing List (PSN-L) From: Greg Subject: Re: geophone tilting Date: Sun, 01 Nov 1998 18:41:05 +0000 GeE777@....... wrote: > > Sean; > OK I haven't seen the specs on this geophone. I assumed it is much like most > miniture and sub miniture geophones used in the exploration today. I'll call > Geospace and get a data sheet. There's a photo on their website. I have the data sheets also and they're very similar to what the web site says. http://www.geospacecorp.com/ http://www.geospacecorp.com/hs1.htm ,Greg _____________________________________________________________________ Public Seismic Network Mailing List (PSN-L) From: Stephen & Kathy Subject: UNLISTED QUAKES and DATAQ DI-150RS Date: Sun, 01 Nov 1998 11:55:46 -0800 Stephen & Kathy wrote: > > Pinpoint EQ Alert News - http://www.televar.com/~earth/alert.html > > FYI Here is a list of quakes that I have recorded that have not > been posted on the Cal. or Nev. quake lists!!! They will probably > be added Mon. or Tues. when they go back to work. > The quakes are probably aftershockes near the Kings Beach area! > Although the Portola and Quincy areas are also about the same distance! > > DATE TIME PST My rough guess > approx. MAG. > > 10/31/98 01:33:32 2.7 > 10/31/98 03:50:29 2.9 > 10/31/98 16:23:29 2.8 > 10/31/98 18:10:35 3.0 > 10/31/98 22:26:08 3.8 This one should have been felt!!! > > I think my Mag. guesses will be on the conservative side!! > Times are approx. because I had to estimate the travel time and the > error of my clock! > The P to S wave times were approx. 13 sec. which puts the travel time > at approx. 18 sec. and my clock gains approx. .5 sec. per hour! I > normally try to set my clock a couple of times a day. > Hi ALL, I sent the above message to Pinpoint earlier so that I could use the lazy way of putting their link in this meassage!!! For those interested in the DataQ DI-150RS you can go to the Pinpoint link above and click on the GIFNOW botton to see a GIF of the KINGS BEACH 5.3 trace that I recorded with my DI-150RS! I'm using one sensor driving 2 single voltage amps. (one turned up to high gain the other turned down to low gain) and recording on both channels! I use a seperate program to add text to the GIF and send them to Bob Shannon who then posts them on his site! It gets updated from time to time whenever I send him new or interesting GIFs. I'm sure he won't mind you returning to see when or if it has been updated!! It's my 2 cents worth of outreach!! Stephen Mortensen PSN Station # 55 near Pilot Hill Ca. _____________________________________________________________________ Public Seismic Network Mailing List (PSN-L) From: Edward Cranswick Subject: Re: WinQuake question Date: Sun, 01 Nov 1998 16:43:48 -0700 Arie- We never got around to checking it out when I visited you in Perth last April, but I believe that the low-gain SG output is acceleration and the high-gain is velocity. If you integrate the acceleration trace with the WinQuake integration option, it should look identical to the velocity, neglecting different noise and digitization levels. If you integrate the velocity trace, you should obtain displacement. and the peak value of that, scaled by the known absolute or estimated relative factors, could be used to calculate Richter local magnitude. Larry and I also got distracted from this issue by the PSN presentation at AGU last December and never resolved the matter. -Edward Arie Verveer wrote: > Hi, > > Larry Cochrane wrote: > > > The magnitude correction number (for a lack of a better term), used by > > WinQuake to determine ML and Ms magnitude, does give WinQuake some Y scale > > information. Station operators determine / calibrate the magnitude > > correction number by using known size events. The problem with this is the > > sensitivity of the system includes any local ground amplification or > > attenuation and is not a direct calibration of the sensor. > > > > I found that the magnitude corrections (Ml & Ms) for the teleseismic and local events > to be different. On my system the teleseismic events are 0.00013 and 0.0003 > for the local events. The match between my recordings of the local events > and the results published by the geophysical observatory are very close. > > >From this, I have assumed that the S-G seismometer that uses larry's electronics > is giving out displacement information. Would that be a correct assumption? > > Arie > > _____________________________________________________________________ > > Public Seismic Network Mailing List (PSN-L) > > To leave this list email listserver@............. with the body of the > message: leave PSN-L -- Edward Cranswick Tel: 303-273-8609 US Geological Survey, MS 966 Fax: 303-273-8600 PO Box 25046, Federal Center cranswick@........ Denver, CO 80225-0046 USA E.M. Forster said, "Only connect". _____________________________________________________________________ Public Seismic Network Mailing List (PSN-L) From: John Hernlund Subject: Quake last night in AZ? Date: Sun, 01 Nov 1998 18:11:56 -0700 (MST) Hello, Anybody find or hear any info on a quake last night at the Grand Canyon? I can't find a listing anywhere... ****************************************************************************** John Hernlund E-mail: hernlund@....... WWW: http://www.mc.maricopa.edu/academic/phy_sci/Geology/hernlund/ http://www.public.asu.edu/~hernlund/ ****************************************************************************** _____________________________________________________________________ Public Seismic Network Mailing List (PSN-L) From: GeE777@....... Subject: Re: geophone tilting Date: Sun, 1 Nov 1998 20:38:15 EST Hello Again, I see now why I was not familar with the HS-1-LT. It is used for industrial vibration monorting and not seismic studies. The HS threw me off as the old HS geophones were manufactured by Hall-Sears, which sold out to GeoSpace a number of years ago. I have 48, HS-J, 14HZ geophone elements in my office I want to get rid of. In a message dated 11/1/98 10:41:54 AM Pacific Standard Time, ghost@............. writes: << There's a photo on their website. I have the data sheets also and they're very similar to what the web site says. >> George Erich Seismic Exploration Consultant P. O. Box 2011, Norwalk, CA 90650, U. S. A. Phone (562) 868-6013 e-mail GeE777@....... 33 53.90N 118 04.53W _____________________________________________________________________ Public Seismic Network Mailing List (PSN-L) From: Brett Nordgren Subject: Update on Web page Date: Sun, 01 Nov 1998 21:38:00 -0500 To all: I have updated the STM-8 feedback analysis "loop2.pdf" Finished the feedback path. available at http://members.home.net/nordgren/public/ Brett Nordgren _____________________________________________________________________ Public Seismic Network Mailing List (PSN-L) From: Karl Cunningham Subject: Re: Quake last night in AZ? Date: Mon, 02 Nov 1998 08:14:37 -0800 At 06:11 PM 11/1/98 -0700, you wrote: >Hello, > Anybody find or hear any info on a quake last night at the Grand Canyon? I >can't find a listing anywhere... John -- Didn't see (or detect) anything near the Grand Canyon. There was a couple in Baja, though. 98/11/02 10:16:06 31.93N 115.77W 6.0 3.9Ml BAJA CALIFORNIA, MEXICO 98/11/02 14:24:01 27.93N 112.94W 10.0 4.3Mb C BAJA CALIFORNIA, MEXICO Karl Cunningham La Mesa, CA. PSN station #40 karlc@....... _____________________________________________________________________ Public Seismic Network Mailing List (PSN-L) From: Karl Cunningham Subject: Re: Update on Web page Date: Mon, 02 Nov 1998 09:02:55 -0800 Brett -- Very interesting analysis. Couple of comments: You wrote: >Finally because the coil resistance is low compared with the three feedback branches, What makes me unsure about this is two things: 1) Sean-Thomas's advice that coil resistance IS significant, and 2) Using his transfer function and changing the coil resistance changes the shape of the response curve. Even the change between 7 ohms and zero makes a noticeable difference. A related issue, as you suggest, is back EMF. I think that the back EMF is more or less proportional to relative magnet-coil velocity, which may be negligible if the feedback is doing its job. And, if it turns out that the coil resistance is not significant, then the feedback can be assumed to be from a high-enough impedance that the back EMF across the coil shouldn't matter anyway. Karl Cunningham La Mesa, CA. PSN station #40 karlc@....... _____________________________________________________________________ Public Seismic Network Mailing List (PSN-L) From: Brett Nordgren Subject: Re: Update on Web page Date: Mon, 02 Nov 1998 13:00:59 -0500 Karl At 09:02 AM 11/2/98 -0800, you wrote: >Brett -- > >Very interesting analysis. > >Couple of comments: > >You wrote: >>Finally because the coil resistance is low compared with the three >feedback branches, > >What makes me unsure about this is two things: 1) Sean-Thomas's advice that >coil resistance IS significant, and 2) Using his transfer function and >changing the coil resistance changes the shape of the response curve. Even >the change between 7 ohms and zero makes a noticeable difference. > I don't disagree. I just assumed zero resistance to simplify this calculation. If the coil resistance is too high, the expressions I was using would no longer be correct, (they would need to become slightly more complicated). The difference between 0 and 8 ohms *is not* significant in the proportional (.002%) and integral (.008%) feedback branches, but at higher frequencies it looks like it does affect the derivative feedback branch; about 1% at 8 Hz and almost 10% by 80 hz. Looks like I need to fix up that branch. Will plan to post the revised data tonight. >A related issue, as you suggest, is back EMF. I think that the back EMF is >more or less proportional to relative magnet-coil velocity, which may be >negligible if the feedback is doing its job. And, if it turns out that the >coil resistance is not significant, then the feedback can be assumed to be >from a high-enough impedance that the back EMF across the coil shouldn't >matter anyway. I think it's almost certain that it doesn't matter. That was just a note to remind me to try sometime to prove it for myself. > >Karl Cunningham Thanks for the help. Brett Nordgren _____________________________________________________________________ Public Seismic Network Mailing List (PSN-L) From: Norman Davis WB6SHI Subject: Re: Windaq trigger mode. Date: Mon, 02 Nov 1998 11:15:50 I have an ongoing dialoge with Ken at widaq and this is the latest message I received from him. The question was, wish it was more that 2 channels. >X-Sender: dataq@............ >Date: Mon, 02 Nov 1998 10:05:12 -0500 >To: Norman Davis WB6SHI >From: Kenneth Spikowski >Subject: Re: Windaq trigger mode. > >An imminent release of the WinDaq/100 software for WinNT (a 32-bit >application which also runs under Win95 or Win98) will allow multiple >DI-150 modules in a system if you have more than one COM port available. It >will be necessary to run multiple instances of the acquisition software, >and the data from each module must go into a separate file. The DLL name >(such as DI100NT.DLL renamed to DI101NT.DLL) and COM port number are passed >to the application as command line parameters such as -DDI101NT.DLL -N2. > > > Norman Davis WB6SHI Shingle Springs, Ca normd@............. http://www.directcon.net/normd/index.htm _____________________________________________________________________ Public Seismic Network Mailing List (PSN-L) From: Gregory Bajuk Subject: Minimun Computer and Win95 Date: Mon, 2 Nov 1998 14:24:57 -0800 (PST) I have been looking for a cheap data logging computer that will run Win95 and the DI-150RS software(which requires WIN95 or above for the trigger feature to work). At some used computer stores the tech people say I need a minimum of a 486DX66 to run Win95. Other stores say I could use a 486SX 25Mhz. At one store the techie said that the minimum configuration to run a bare bones Win95 is 486SX 25, 8meg ram, about 150 meg hard drive(60 meg for bare bones Win95, 2 meg for dataq software, and the rest for data logging), and a CD ROM drive to load Win95 into the computer. Once loaded the CD ROM isn't needed. Does anyone on the list have some information about this? Thanks Greg Bajuk _____________________________________________________________________ Public Seismic Network Mailing List (PSN-L) From: Greg Subject: Re: Minimun Computer and Win95 Date: Mon, 02 Nov 1998 22:58:34 +0000 Gregory Bajuk wrote: > > I have been looking for a cheap data logging computer that will run Win95 > and the DI-150RS software(which requires WIN95 or above for the trigger > feature to work). At some used computer stores the tech people say I need > a minimum of a 486DX66 to run Win95. Other stores say I could use a > 486SX 25Mhz. The Windows 95 box says 386DX, 4 MB RAM, 35-40 MB disk space. I have seen it on a 486SX20, 12 MB RAM and it's OK. If you're worried about price, shop around a bit more. I just upgraded my SDR machine to a 486DX2/50 with 32 MB RAM and a 213 MB disk for about $50. It used to be a 386DX40 with 20 MB RAM. I had to do a lot of swapping and switching to put it together. The $50 was for a box of spare parts and spare cases from an engineering company now using Pentium IIs. If I upgrade my primary computer's disk, the current disk will get plugged into the 486, so I can put Linux on it. I just put a new modem in a computer for someone else. They bought a 486DX2/66, 12 MB RAM, 200 MB disk with a nice 15" monitor and a color Canon printer at a garage sale for $40. It needed one $10 cable. Have fun, Greg _____________________________________________________________________ Public Seismic Network Mailing List (PSN-L) From: ralvarez@........ (Raul Alvarez) Subject: Re: Minimun Computer and Win95 Date: Mon, 2 Nov 1998 16:59:25 -0700 (MST) >I have been looking for a cheap data logging computer that will run Win95 >and the DI-150RS software(which requires WIN95 or above for the trigger >feature to work). At some used computer stores the tech people say I need >a minimum of a 486DX66 to run Win95. Other stores say I could use a >486SX 25Mhz. > If you are searching for and inexpensive 486 (or any other), try attending a local university surplus auction. Around here (Colorado) I see MANY 486 type machines go in the $15 range. Start by calling the property disposal office or central receiving. They can probably tell you if they have auctions. Avoid calling the "information office", they often don't have knowledge of that type of information. BTW, a LOT of good scientific and test equipment is found at these auctions. Raul _____________________________________________________________________ Public Seismic Network Mailing List (PSN-L) From: "Walt Williams" Subject: PSN-L: Minimun Computer and Win95 Date: Mon, 2 Nov 1998 15:59:49 +0000 Hello Gregory, Minimum computer speed is highly subjective and dependent upon individual preferences as well as the required application performance. If you were to say, want to run AutoCAD 14 in Win95 (and be productive), the minimum machine hardware would a fast Pentium with much ram, ~64mb upto 256 mb. I built my nephew a Win95 machine which he uses to play DukeNukem :) and it is a 486 DX2/66 with 16mb of ram. It is adequate. I have an NT network with six machines and the kids come over on weekends, they and my nephew all play DukeNukem on it via the network, 16 year-old Romper-Room :) I personally would not run Win95 in anything less than 486DX/2-66 and 16mb ram. The more graphics the more ram needed --in any machine. Best Wishes, Walt Williams, 98.11.02 dfheli@.............. http://www.pacificnet.net/~dfheli ============================ ------- Forwarded Message Follows ------- Date: Mon, 2 Nov 1998 14:24:57 -0800 (PST) From: Gregory Bajuk To: psn-l@............. Subject: Minimun Computer and Win95 Reply-to: PSN-L Mailing List I have been looking for a cheap data logging computer that will run Win95 and the DI-150RS software(which requires WIN95 or above for the trigger feature to work). At some used computer stores the tech people say I need a minimum of a 486DX66 to run Win95. Other stores say I could use a 486SX 25Mhz. At one store the techie said that the minimum configuration to run a bare bones Win95 is 486SX 25, 8meg ram, about 150 meg hard drive(60 meg for bare bones Win95, 2 meg for dataq software, and the rest for data logging), and a CD ROM drive to load Win95 into the computer. Once loaded the CD ROM isn't needed. Does anyone on the list have some information about this? Thanks Greg Bajuk _____________________________________________________________________ Public Seismic Network Mailing List (PSN-L) _____________________________________________________________________ Public Seismic Network Mailing List (PSN-L) From: David Josephson Subject: Re: Minimun Computer and Win95 Date: Mon, 2 Nov 1998 16:06:56 -0800 (PST) Any 486 will work but you need at least 16 MB of memory to avoid major slowdowns as the operating system moves pieces of itself on and off disk. Around here 486's with 16 MB and a small hard drive sell for about $100. -- David Josephson / Josephson Engineering / San Jose CA / david@............. _____________________________________________________________________ Public Seismic Network Mailing List (PSN-L) From: Karl Cunningham Subject: Re: Minimun Computer and Win95 Date: Mon, 02 Nov 1998 17:06:27 -0800 At 02:24 PM 11/2/98 -0800, you wrote: >I have been looking for a cheap data logging computer that will run Win95 >and the DI-150RS software(which requires WIN95 or above for the trigger >feature to work). At some used computer stores the tech people say I need >a minimum of a 486DX66 to run Win95. Other stores say I could use a >486SX 25Mhz. > >At one store the techie said that the minimum configuration to run a bare >bones Win95 is 486SX 25, 8meg ram, about 150 meg hard drive(60 meg for >bare bones Win95, 2 meg for dataq software, and the rest for data >logging), and a CD ROM drive to load Win95 into the computer. Once loaded >the CD ROM isn't needed. Greg -- Look at flea markets and swap meets. Some even specialize in electronic stuff. The mother board I am using for my SDR machine is a 486dx-2/66 VLB and cost me $3. Others I know at work have gotten similar motherboards in working order for $1 including processor. _____________________________________________________________________ Public Seismic Network Mailing List (PSN-L) From: Wayne Abraham Subject: New Public Seismic Network Date: Mon, 02 Nov 1998 21:13:46 -0400 Hello, My name is Wayne Abraham on the Caribbean island of Dominica. We are located midway down the island chain, about 500 miles south-east of Puerto Rico. Dominica (not the Dominican Republic) is an independent island nation which attained its independence from Great Britain in November 1978. I am not a geologist, seismologist, volcanologist or anything near that. I am an electrician who got interested in the field because of certain circumstances. Our island is the most rugged of all the caribbean islands and we have 10 volcanoes on 289 square miles. We sit on the Atlantic/Caribbean plate boundry, have the most volcanoes per square mile and the world's largest boiling lake. Recently there has been an upsurge of activity in the vicinity of a cluster of volcanoes in the south of the island. Numerous tremours have been felt by locals and there has been rockfalls and cracking of concrete structures. The island's seismic activity is being monitored by the Seismic Research Unit of the University of the West Indies in Trinidad. I can give more geologic background information on the island if anyone is interested. I was able to get our local amateur radio club, of which I am a member, interested in setting up a public seismic network where we could share data from both local and regional events. There is no public seismic network on any of the islands and most people seem to think that only professionals can monitor seismic activity. This way of thinking I wish to change and I have already found 5 members of our club who are willing to get into actively monitoring seismic events. Our problem though is funds. Our club operates on a shoe string budget and most of the repeater equipment we have on our mountains are donated. I am looking for anyone who may be able to assist us in getting donated equipment etc. for our project. Your assistance will be greatly appreciated. Wayne _____________________________________________________________________ Public Seismic Network Mailing List (PSN-L) From: "Rex Klopfenstein, Jr." Subject: Re: Minimun Computer and Win95 Date: Mon, 02 Nov 1998 20:25:03 -0500 We had several at where I work and we couldn't give them away!! Karl Cunningham wrote: > The mother board I am using for my SDR machine is a 486dx-2/66 VLB > and cost me $3. Others I know at work have gotten similar motherboards in > working order for $1 including processor. > > > -- Rex Klopfenstein, Jr. Bowling Green, OH rklopfen@......... www.wcnet.org/~rklopfen _____________________________________________________________________ Public Seismic Network Mailing List (PSN-L) From: Larry Cochrane Subject: Re: Minimun Computer and Win95 Date: Mon, 02 Nov 1998 20:37:29 -0800 If you do buy a used computer, make sure its Y2K compliant. There are a lot of motherboards / systems that will not work correctly after 12/31/1999. A simple way to test for the Y2K bug is to boot up the system and set the date and time to 12/31/1999 23:55:00. Now shutdown the system and wait 10 minutes. After booting up again, check the date/time. If the date goes back to 1980, or some other date other than 1/1/2000, the system is not Y2K compliant. -Larry Cochrane Redwood City, PSN At 02:24 PM 11/2/98 -0800, you wrote: >I have been looking for a cheap data logging computer that will run Win95 >and the DI-150RS software(which requires WIN95 or above for the trigger >feature to work). At some used computer stores the tech people say I need >a minimum of a 486DX66 to run Win95. Other stores say I could use a >486SX 25Mhz. > >At one store the techie said that the minimum configuration to run a bare >bones Win95 is 486SX 25, 8meg ram, about 150 meg hard drive(60 meg for >bare bones Win95, 2 meg for dataq software, and the rest for data >logging), and a CD ROM drive to load Win95 into the computer. Once loaded >the CD ROM isn't needed. > >Does anyone on the list have some information about this? > >Thanks Greg Bajuk _____________________________________________________________________ Public Seismic Network Mailing List (PSN-L) From: curtis Subject: Re: Minimun Computer and Win95 Date: Mon, 02 Nov 1998 20:56:32 +0000 But Larry _if_ 1K=1024 _then_ Y2K will not occur until 2048 _and_ _if so_ , I don't think we will have to worry about it (snicker). Apologies to the list, but I could not resist the humor (smile). Larry Cochrane wrote: > > If you do buy a used computer, make sure its Y2K compliant. There are a lot > of motherboards / systems that will not work correctly after 12/31/1999. > > A simple way to test for the Y2K bug is to boot up the system and set the > date and time to 12/31/1999 23:55:00. Now shutdown the system and wait 10 > minutes. After booting up again, check the date/time. If the date goes back > to 1980, or some other date other than 1/1/2000, the system is not Y2K > compliant. > > -Larry Cochrane > Redwood City, PSN > > At 02:24 PM 11/2/98 -0800, you wrote: > >I have been looking for a cheap data logging computer that will run Win95 > >and the DI-150RS software(which requires WIN95 or above for the trigger > >feature to work). At some used computer stores the tech people say I need > >a minimum of a 486DX66 to run Win95. Other stores say I could use a > >486SX 25Mhz. > > > >At one store the techie said that the minimum configuration to run a bare > >bones Win95 is 486SX 25, 8meg ram, about 150 meg hard drive(60 meg for > >bare bones Win95, 2 meg for dataq software, and the rest for data > >logging), and a CD ROM drive to load Win95 into the computer. Once loaded > >the CD ROM isn't needed. > > > >Does anyone on the list have some information about this? > > > >Thanks Greg Bajuk > > _____________________________________________________________________ > > Public Seismic Network Mailing List (PSN-L) > > To leave this list email listserver@............. with the body of the > message: leave PSN-L -- curtis - ufkartfm@........... - site administrator for Nobody I want Nobody to control my life! How about you? http://www.netvideo.com/nobody -Please Register and Vote for the Candidate of Your Choice- _____________________________________________________________________ Public Seismic Network Mailing List (PSN-L) From: John Hernlund Subject: Re: New Public Seismic Network Date: Tue, 03 Nov 1998 07:55:28 -0700 (MST) On Mon, 2 Nov 1998, Wayne Abraham wrote: > My name is Wayne Abraham on the Caribbean island of Dominica. > I am not a geologist, seismologist, volcanologist or anything near that. > I am an electrician who got interested in the field because of certain > circumstances. Our island is the most rugged of all the caribbean > islands and we have 10 volcanoes on 289 square miles. We sit on the > Atlantic/Caribbean plate boundry, have the most volcanoes per square > mile and the world's largest boiling lake. Recently there has been an > upsurge of activity in the vicinity of a cluster of volcanoes in the > south of the island. Numerous tremours have been felt by locals and > there has been rockfalls and cracking of concrete structures. The > island's seismic activity is being monitored by the Seismic Research > Unit of the University of the West Indies in Trinidad. I can give more > geologic background information on the island if anyone is interested. Absolutely... > I was able to get our local amateur radio club, of which I am a member, > interested in setting up a public seismic network where we could share > data from both local and regional events. There is no public seismic > network on any of the islands and most people seem to think that only > professionals can monitor seismic activity. This way of thinking I wish > to change and I have already found 5 members of our club who are willing > to get into actively monitoring seismic events. It sounds like all of you have more than enough reason to monitor activity for yourselves! That way you can get an idea of what is happening volcanically without having to hear it through more official channels... > Our problem though is funds. Our club operates on a shoe string budget > and most of the repeater equipment we have on our mountains are donated. > I am looking for anyone who may be able to assist us in getting donated > equipment etc. for our project. > Your assistance will be greatly appreciated. If I hear of anything, I'll be glad to help. I might be able to scrounge up some older equipment like a short period vertical seismometer... I'll check on that, and see if I find anything. ****************************************************************************** John Hernlund E-mail: hernlund@....... WWW: http://www.mc.maricopa.edu/academic/phy_sci/Geology/hernlund/ http://www.public.asu.edu/~hernlund/ ****************************************************************************** _____________________________________________________________________ Public Seismic Network Mailing List (PSN-L) From: John Lahr Subject: DI-150RS limitations Date: Tue, 3 Nov 1998 14:31:49 -0700 (MST) Unless someone writes some seismology software for the DI-150, it looks like its use is limited by poor timing and lack of pre-trigger information for serious seismology. JCLahr > From JohnJan@........ Mon Nov 2 20:51 MST 1998 > X-Sender: jlahr@................ > Date: Mon, 02 Nov 1998 20:51:57 -0700 > To: "John C Lahr, Lakewood, CO " > From: The Lahrs > Subject: Re: DI-150RS software > Mime-Version: 1.0 > > >Return-Path: > >X-Sender: dataq@............ (Unverified) > >Date: Mon, 02 Nov 1998 14:08:19 -0500 > >To: The Lahrs > >From: Kenneth Spikowski > >Subject: Re: DI-150RS software > > > >The time of the first sample recorded in the header of a WDQ file is only > >stored to the nearest second. The start time of each triggered burst is > >stored in the trailer as the number of seconds relative to this start time. > >Even if we were to change the file format to store the trailer values as > >the number of .01 seconds relative, the long-term accuracy would be only as > >good as the PC clock frequency, typically 1 second per day. The TBF values > >displayed by WWB within each burst would only be as accurate as the crystal > >timing the COM ports. Timing events to .01 second would require hardware > >synchronization to WWVL or GPS satellites. > > > >The header and trailer formats for WinDaq files are available on our Web > >site under On-line Articles, WINDAQ File Format. The 200SDK Installation > >for Windows also contains C header files HDRDEF.H and HDRDEF32.H that > >define the header. > > > >Triggered Storage mode was developed as a low-budget feature which looks at > >the data in the 32-bit disk storage process. It is enabled by setting data > >bit 1 in the trglevel field of the chinfo of struct hdrcmn. The ground > >rules were that it need not run under Windows 3.x and would not support > >pretrigger data (as most of our more expensive hardware does). > > > >We could probably allow Triggered Storage mode to scroll if the Erase Bar > >is turned off if we felt that this behavior would not confuse users. We are > >running out of spare bits in the header and hate to waste them on something > >like this, hastening a header change with serious compatibility implications. > > > > > ************************** > Dear Ken, > > I am a seismologist with the US Geological Survey and have been working > on a "table-top" seismology demonstration for grades K-12. As part of > the setup I used a small exploration geophone in conjunction with an > AD and computer display in "scroll mode." > > I have been searching for the most cost effective AD and computer software > to recommend to teachers, as they are generally on a very tight budget. > So far, the DATAQ DI-150RS and its acquisition software is the best I > have found, and I want to thank you for creating such a cost effective > product. > > In fact, with the trigger mode available now, teachers could easily set up > an operating seismograph to record earthquakes. The key thing that is > necessary for getting useful seismic data is knowing the time of every > sample. To what precision is the time of the first sample recorded in the > header of a WDQ file? Is this only to the nearest second? If so, could > a change be made to record this information to the nearest .01 second? > If the first sample time were recorded to the nearest .01 second, how > close would it be to the PC system time? In other words, does the > acquisition system keep close track of the PC's clock in creating its > time stamp information? > > Could I get the details of the header format? I would like to convert > the .WDQ files into the format used to share data within the Public > Seismic Network community. > > Once the header time is accurate and precise to .01 second, then for > seismology it would be desirable for the time indicated for the > cursor in the WWB browser to given to .01 seconds as well. Once this > change was made, one could line the cursor up with a particular phase > and read off the arrival time. > > One other thing that is required for seismology is the inclusion of > some pre-trigger data with each recorded event. Usually the arrival > builds up over a second or two prior to reaching the trigger threshold. > In seismology we want to measure the time of the first energy, which is > then prior to the trigger time. > > A less critical, but desirable change, would be to make the scroll mode > available when in trigger mode. The current free-run mode, where the > screen is overwritten, is a bit confusing. > > I wish I could say that the USGS has a lot of money to contribute to > making these changes, but unfortunately this is not the case. My > efforts in this are mostly "after hours." However, these changes would > make your product more appealing to teachers and to amateur seismologists, > which I think would lead to more sales. At $50 each, this is clearly not > a big money maker, but there must be good advertising value and good will > created by providing an effective and popular educational tool. > > This coming Thursday I'll be demonstrating Table-Top Seismology at the > National Middle School Association's annual conference that has an > attendance of 10,000 teachers. If you want, I'll let you know what > response I get from the teachers. > > Cheers, > John > > > > > > > * John C. and Jan H. Lahr * > * JohnJan@........ * > * 1925 Foothills Road * > * Golden, Colorado 80401-1718 * > * (303) 215-9913 * > * http://lahr.org/john-jan * > * AOL version of homepage: * > * http://lahr.org/john-jan/homepage.html * > * http://giseis.alaska.edu/lahr * > _____________________________________________________________________ Public Seismic Network Mailing List (PSN-L) From: "Rex Klopfenstein, Jr." Subject: Re: Minimun Computer and Win95 Date: Tue, 03 Nov 1998 18:50:35 -0500 Some of the newer motherboards can be upgraded to Y2K compliant by updating the BIOS which can be "flashed". We had a job we were reworking and it had a IBM ValuePoint box. We found a BIOS upgrade at IBM's homepage. Larry Cochrane wrote: > If you do buy a used computer, make sure its Y2K compliant. There are a lot > of motherboards / systems that will not work correctly after 12/31/1999. > -- Rex Klopfenstein, Jr. Bowling Green, OH rklopfen@......... www.wcnet.org/~rklopfen _____________________________________________________________________ Public Seismic Network Mailing List (PSN-L) From: "Rex Klopfenstein, Jr." Subject: PSN - SDR Question? Date: Tue, 03 Nov 1998 19:10:30 -0500 I have just installed my SDR acquisition board (16 bit) into my system and now in the process of 'playing'. I have one question. When I place a very short jumper between an analog input and analog ground right at the plug on the card I would expect to see 0 counts or very close to 0. What I do see is a signal that ranges from +3 to -15 or -16 counts using the max/min function on the analog count output display. Is this a problem? It seems that I have lost the difference between the 12 bit and the 16 bit adc! -- Rex Klopfenstein, Jr. Bowling Green, OH rklopfen@......... www.wcnet.org/~rklopfen _____________________________________________________________________ Public Seismic Network Mailing List (PSN-L) From: Karl Cunningham Subject: Re: Minimun Computer and Win95 Date: Tue, 03 Nov 1998 16:14:07 -0800 At 06:50 PM 11/3/98 -0500, you wrote: >Some of the newer motherboards can be upgraded to Y2K compliant by updating the >BIOS which can be "flashed". We had a job we were reworking and it had a IBM >ValuePoint box. We found a BIOS upgrade at IBM's homepage. And some of the motherboards that are not totally compliant and for which upgrades are not available can be used if not allowed to run over the Y2K transition. I've experimented with mine, and have found that once it gets past 00:00:00 on 1/1/2000, it's fine. So, I plan to stop SDR on 12/31/1999 at 23:59:45 or so, and turn the computer off. I'll reboot it about 30 seconds later and set the clock (which will have reverted to 1980), then start SDR again. If it goes like my tests have, all should be fine from then on. Karl Cunningham La Mesa, CA. PSN station #40 karlc@....... _____________________________________________________________________ Public Seismic Network Mailing List (PSN-L) From: Larry Cochrane Subject: Re: Minimun Computer and Win95 Date: Tue, 03 Nov 1998 18:08:24 -0800 I have been think about adding a year test to SDR. SDR would check the year when it first starts up. If its below say 1998, it would add an offset, supplied by the user (and saved in the INI file), to make the year correct. -Larry Cochrane At 04:14 PM 11/3/98 -0800, Karl Cunningham wrote: >At 06:50 PM 11/3/98 -0500, you wrote: >>Some of the newer motherboards can be upgraded to Y2K compliant by >updating the >>BIOS which can be "flashed". We had a job we were reworking and it had a IBM >>ValuePoint box. We found a BIOS upgrade at IBM's homepage. > >And some of the motherboards that are not totally compliant and for which >upgrades are not available can be used if not allowed to run over the Y2K >transition. I've experimented with mine, and have found that once it gets >past 00:00:00 on 1/1/2000, it's fine. So, I plan to stop SDR on 12/31/1999 >at 23:59:45 or so, and turn the computer off. I'll reboot it about 30 >seconds later and set the clock (which will have reverted to 1980), then >start SDR again. If it goes like my tests have, all should be fine from >then on. > > >Karl Cunningham >La Mesa, CA. >PSN station #40 >karlc@....... > >_____________________________________________________________________ > >Public Seismic Network Mailing List (PSN-L) > >To leave this list email listserver@............. with the body of the >message: leave PSN-L > _____________________________________________________________________ Public Seismic Network Mailing List (PSN-L) From: Jim Hannon Subject: Re: DI-150RS limitations Date: Tue, 03 Nov 1998 20:11:45 -0600 John, You might want to investigate Bsoft http://www.bsof.com/anaprod.htm products for an inexpensive A/D converter. They probably still need some software but would not have the timing problems associated with using the serial port. -- Jim Hannon http://soli.inav.net/~jmhannon/ 42,11.90N 91,39.26W WB0TXL _____________________________________________________________________ Public Seismic Network Mailing List (PSN-L) From: Norman Davis WB6SHI Subject: Re: Minimun Computer and Win95 Date: Tue, 03 Nov 1998 18:32:49 At 02:24 PM 11/2/98 -0800, you wrote: >I have been looking for a cheap data logging computer that will run Win95 >and the DI-150RS software(which requires WIN95 or above for the trigger >feature to work). At some used computer stores the tech people say I need >a minimum of a 486DX66 to run Win95. Other stores say I could use a >486SX 25Mhz. I am running win95 on a 486dx2 66 and 8 megs of ram and 500mb drive. It is ok for light weight stuff like data logging but internet is very slow. I am sure that 16 megs of ram would help. Norman Davis WB6SHI Shingle Springs, Ca normd@............. http://www.directcon.net/normd/index.htm _____________________________________________________________________ Public Seismic Network Mailing List (PSN-L) From: barry lotz Subject: Re: Minimun Computer and Win95 Date: Tue, 03 Nov 1998 18:46:30 -0800 Rex I also saw recently a ISA card advertised to allow your system to be compliant. I can't remember where I saw it. Barry Rex Klopfenstein, Jr. wrote: > Some of the newer motherboards can be upgraded to Y2K compliant by updating the > BIOS which can be "flashed". We had a job we were reworking and it had a IBM > ValuePoint box. We found a BIOS upgrade at IBM's homepage. Rex Klopfenstein, Jr. wrote: > Some of the newer motherboards can be upgraded to Y2K compliant by updating the > BIOS which can be "flashed". We had a job we were reworking and it had a IBM > ValuePoint box. We found a BIOS upgrade at IBM's homepage. > > Larry Cochrane wrote: > > > If you do buy a used computer, make sure its Y2K compliant. There are a lot > > of motherboards / systems that will not work correctly after 12/31/1999. > > > > -- > Rex Klopfenstein, Jr. > Bowling Green, OH > rklopfen@......... > www.wcnet.org/~rklopfen > > _____________________________________________________________________ > > Public Seismic Network Mailing List (PSN-L) > > To leave this list email listserver@............. with the body of the > message: leave PSN-L _____________________________________________________________________ Public Seismic Network Mailing List (PSN-L) From: Ted Blank Subject: Re: DI-150RS limitations Date: Tue, 3 Nov 1998 22:42:19 -0800 (PST) EMON already supports the ANA201 from Bsoft. However I did not find it to be a reliable card in my tests. For an inexpensive A/D card I recommend the Computer Boards CIO-DAS08jr/16-AO. The engineers are former Kiethly-Metrabyte employees, and for $99 you get a really rock solid and easy to program (yay!) board. (Naturally I have no investment in this company - they are doing well which means I never would have bought their stock in the first place) PS - my 14 yr old son and I were printing pages from www.chemicalelements.com for his science course. I printed off the license page which gives permission to print any pages you want. He asked what a license was, so I explained that it gave you permission to use a program or web site in a certain way. He thought about it for a minute, then asked, "Is that what it means when the computer says 'your program has performed an illegal operation and will be shut down?'" I am still laughing. I think. Ted Blank San Jose, California On Tue, 3 Nov 1998, Jim Hannon wrote: > John, > You might want to investigate Bsoft http://www.bsof.com/anaprod.htm > products for an inexpensive A/D converter. They probably still need some > software but would not have the timing problems associated with using > the serial port. > > -- > Jim Hannon > http://soli.inav.net/~jmhannon/ > 42,11.90N 91,39.26W > WB0TXL > > > _____________________________________________________________________ > > Public Seismic Network Mailing List (PSN-L) > > To leave this list email listserver@............. with the body of the > message: leave PSN-L > _____________________________________________________________________ Public Seismic Network Mailing List (PSN-L) From: "Rex Klopfenstein, Jr." Subject: PSN - VBB Prototype Picture Date: Wed, 04 Nov 1998 09:06:25 -0500 Sean I was reading the abstract of your 1998 paper. I took a look at picture of your prototype. Have you made some changes to the design? It looks longer and the displacement transducer is located differently that in your drawings. -- Rex Klopfenstein, Jr. Bowling Green, OH rklopfen@......... http://www.wcnet.org/~rklopfen _____________________________________________________________________ Public Seismic Network Mailing List (PSN-L) From: "Dan" Subject: Re:ISA CARD FIX Y-2K Date: Wed, 4 Nov 1998 08:02:54 -0800 The ISA card for y2k fix was in this months sale paper, from -- I think the name was either j&r or J&D micro divice in sunnvale ca.. it sold for 29.95. in you need the address i will try to find the add. my wife says i never throw anything away Dan - --Original Message----- From: barry lotz To: PSN-L Mailing List Date: Tuesday, November 03, 1998 6:45 PM Subject: Re: Minimun Computer and Win95 >Rex > I also saw recently a ISA card advertised to allow your system to be compliant. >I can't remember where I saw it. > Barry > > >Rex Klopfenstein, Jr. wrote: > >> Some of the newer motherboards can be upgraded to Y2K compliant by updating the >> BIOS which can be "flashed". We had a job we were reworking and it had a IBM >> ValuePoint box. We found a BIOS upgrade at IBM's homepage. > >Rex Klopfenstein, Jr. wrote: > >> Some of the newer motherboards can be upgraded to Y2K compliant by updating the >> BIOS which can be "flashed". We had a job we were reworking and it had a IBM >> ValuePoint box. We found a BIOS upgrade at IBM's homepage. >> >> Larry Cochrane wrote: >> >> > If you do buy a used computer, make sure its Y2K compliant. There are a lot >> > of motherboards / systems that will not work correctly after 12/31/1999. >> > >> >> -- >> Rex Klopfenstein, Jr. >> Bowling Green, OH >> rklopfen@......... >> www.wcnet.org/~rklopfen >> >> _____________________________________________________________________ >> >> Public Seismic Network Mailing List (PSN-L) >> >> To leave this list email listserver@............. with the body of the >> message: leave PSN-L > > >_____________________________________________________________________ > >Public Seismic Network Mailing List (PSN-L) > >To leave this list email listserver@............. with the body of the >message: leave PSN-L > _____________________________________________________________________ Public Seismic Network Mailing List (PSN-L) From: Karl Cunningham Subject: Re: PSN - SDR Question? Date: Wed, 04 Nov 1998 08:23:04 -0800 At 07:10 PM 11/3/98 -0500, you wrote: >I have just installed my SDR acquisition board (16 bit) into my system >and now in the process of 'playing'. I have one question. When I place >a very short jumper between an analog input and analog ground right at >the plug on the card I would expect to see 0 counts or very close to 0. >What I do see is a signal that ranges from +3 to -15 or -16 counts using >the max/min function on the analog count output display. Is this a >problem? It seems that I have lost the difference between the 12 bit >and the 16 bit adc! Rex -- That noise level sounds a little high compared to what I see, but not too much different. My noise level using just the A/D card runs between +5 to -5 counts -- about 10 counts total. You can use the zero offset function in SDR to make your noise symmetrical around zero. You might try plugging the A/D card into a different slot in the computer. I found that the least-noisy slot was the one farthest from the hard disk (closest to the side panel of the enclosure). Also move other plug-in cards as far away from the A/D card as you can. Some noise level is normal. I looked up the specs on the A/D chip and found that +/- 3 to 5 counts is not unusual. It's too bad that a chip manufacturer makes a 16-bit part that has such a noise level that makes the last 2-3 bits unusable without averaging. I wonder if there is a better chip that could be used (perhaps for more $) without circuit or software changes. Larry may have looked into this. Karl Cunningham La Mesa, CA. PSN station #40 karlc@....... _____________________________________________________________________ Public Seismic Network Mailing List (PSN-L) From: Greg Subject: Geophones for sale Date: Wed, 04 Nov 1998 17:12:21 +0000 I think I've pretty much contacted every geophone dealer in the USA. I ended up getting the Geospace GS-11D 4.5 Hz. The next step up is R.T. Clark. The person on the phone said they have some 1 Hz seismometers for $375-7__? US. The next step down appears to be the used geophones from Mitcham Industries. There's very little price difference between 4.5 Hz and the higher frequencies. After that get a loan. ;) I thought someone might want to know. Also I found a web site of a student working on using a GS-11D as a cheap seismometer. No response yet. Of course, I'm bugging him. http://cdr.stanford.edu/DD/SMSSL/Geophones/GeophoneResearch.html ,Greg _____________________________________________________________________ Public Seismic Network Mailing List (PSN-L) From: Ted Blank Subject: Re:ISA CARD FIX Y-2K Date: Wed, 4 Nov 1998 10:32:07 -0800 (PST) That would be JDR Micro Devices. Ted Blank San Jose, California On Wed, 4 Nov 1998, Dan wrote: > The ISA card for y2k fix was in this months sale paper, from -- I think > the name was either j&r or J&D micro divice in sunnvale ca.. it sold for > 29.95. > in you need the address i will try to find the add. > my wife says i never throw anything away > Dan > - > --Original Message----- > From: barry lotz > To: PSN-L Mailing List > Date: Tuesday, November 03, 1998 6:45 PM > Subject: Re: Minimun Computer and Win95 > > > >Rex > > I also saw recently a ISA card advertised to allow your system to be > compliant. > >I can't remember where I saw it. > > Barry > > > > > >Rex Klopfenstein, Jr. wrote: > > > >> Some of the newer motherboards can be upgraded to Y2K compliant by > updating the > >> BIOS which can be "flashed". We had a job we were reworking and it had a > IBM > >> ValuePoint box. We found a BIOS upgrade at IBM's homepage. > > > >Rex Klopfenstein, Jr. wrote: > > > >> Some of the newer motherboards can be upgraded to Y2K compliant by > updating the > >> BIOS which can be "flashed". We had a job we were reworking and it had a > IBM > >> ValuePoint box. We found a BIOS upgrade at IBM's homepage. > >> > >> Larry Cochrane wrote: > >> > >> > If you do buy a used computer, make sure its Y2K compliant. There are a > lot > >> > of motherboards / systems that will not work correctly after > 12/31/1999. > >> > > >> > >> -- > >> Rex Klopfenstein, Jr. > >> Bowling Green, OH > >> rklopfen@......... > >> www.wcnet.org/~rklopfen > >> > >> _____________________________________________________________________ > >> > >> Public Seismic Network Mailing List (PSN-L) > >> > >> To leave this list email listserver@............. with the body of the > >> message: leave PSN-L > > > > > >_____________________________________________________________________ > > > >Public Seismic Network Mailing List (PSN-L) > > > >To leave this list email listserver@............. with the body of the > >message: leave PSN-L > > > > > > > _____________________________________________________________________ > > Public Seismic Network Mailing List (PSN-L) > > To leave this list email listserver@............. with the body of the > message: leave PSN-L > _____________________________________________________________________ Public Seismic Network Mailing List (PSN-L) From: Greg Subject: Re: ISA CARD FIX Y-2K Date: Wed, 04 Nov 1998 14:05:33 -0700 http://www.jdr.com/jdr.exe Search for y2k 2 results. Two different cards. One is $70 and the other is $90. I doubt most people will need it. What are the odds that an earthquake will happen at midnight Dec 31, 1999? An earthquake that your station would see? I've found a total of one computer that correctly flips over to 2000. It's an Intel motherboard Pentium that I built. It's pretty old too. I couldn't find a direct URL. Their site is totally dependent on the CGI script jdr.exe. Which is odd, because CGI will increase the server load. ,Greg _____________________________________________________________________ Public Seismic Network Mailing List (PSN-L) From: John Lahr Subject: Re: DI-150RS limitations Date: Wed, 4 Nov 1998 15:08:26 -0700 (MST) > From: Jim Hannon > You might want to investigate Bsoft http://www.bsof.com/anaprod.htm > products for an inexpensive A/D converter. They probably still need some > software but would not have the timing problems associated with using > the serial port. > For an internal AD, I would get Larry's board. The reason I'm trying to a serial port AD is for K-12 teachers -- many would be hesitant to install a board within a PC and keeping things exterior to the PC also makes system much more portable. I have a draft version of my "Table-Top Earthquakes" demo on the web now, and would love to get feedback for corrections, improvements, etc. The URL is: http://giseis.alaska.edu/lahr/tabletop/ Cheers, JCLahr ################################## John C. Lahr ################################# Seismologist ################################ U.S. Geological Survey ############################### Geologic Hazards Team, MS966 ############################## PO Box 25046 #############################/############################## ############################/############################### Denver, Colorado 80225-0046 ################################ Phone: (303) 273-8596 ################################## Fax: (303) 273-8600 ################################### lahr@........ ##################################### http://giseis.alaska.edu/lahr http://lahr.org/john-jan _____________________________________________________________________ Public Seismic Network Mailing List (PSN-L) From: Wayne Abraham Subject: Telemetry Decode Date: Wed, 04 Nov 1998 19:27:46 -0400 Does anybody know where I can find software that will allow me to decode USGS telemetry received from a scanner into my sound card (if such a thing exists)? Wayne Abraham. _____________________________________________________________________ Public Seismic Network Mailing List (PSN-L) From: John Lahr Subject: On-Line Earthquake Education Date: Wed, 4 Nov 1998 16:36:13 -0700 (MST) Speaking of education modules, there is an extensive one on earthquakes developed by the Southern California Earthquake Center. Check out: http://www.scecdc.scec.org/Module/ JCLahr > >Date: Wed, 04 Nov 1998 12:16:31 -0800 > >Reply-To: benthien@............. > >Sender: owner-scecall-l@....... > >From: Mark Benthien > >To: scecall > >Subject: SCEC Regional Seismicity Module Version 1.0 Release > >We are pleased to announce the release of version 1.0 of the SCEC > >web-based education module "Investigating Earthquakes through > >Regional Seismicity". The module is now available at > >http://www.scecdc.scec.org/Module/. > > > >This module has been designed under the unifying concept "The earth is > >constantly changing". The module is designed for use both in the classroom > >(high school and undergraduate levels), as part of an earth-science > >curriculum, > >or standalone, for use by the general public interested in a user-friendly > >resource for basic seismological information. The content and format of > >this module have been reviewed by scientists and educators alike, and > >portions of the module have been field tested in high school and community > >college settings. > > > >Each section of the module consists of a sequence of text "pages" -- with > >explanatory maps, diagrams, and other inline images -- hyperlinked to > >activities, in which students can develop an understanding of the concepts > >in a more interactive way. Many of these activities are, in turn, linked to > >separate on-line resources (e.g. fault maps), and interfaces that provide > >access > >to seismological data archived at the SCEC Data Center. The ability to > >learn about earthquakes using a continuously updated storehouse of latest > >earthquake data provides an educational experience that relates to the > >"real world". > >The modular design allows any future sections to be easily appended. Version > >2.0 of the module will include a second section ("The Distribution of > >Earthquakes"). We anticipate that this section will be available in time > >for the December AGU meeting in San Francisco this year. Plans for further > >development include a section on "Measuring Earthquakes". > > > >In order to ensure that the module will comply with education standards, > >the module is currently undergoing a curriculum review through the > >Education and Outreach office of the Southern California Earthquake Center. > >We have developed a "storyline" for the module, as outlined in the > >attachment (storyline.gif). We hope that this material will be useful > >to educators in the earth sciences, as well as mathematics, physics, etc. > > > >We have made version 1.0 of the module ("What is an Earthquake?") available > >on the Web in order to receive feedback and comments from educators, > >researchers, and the general public on how to improve this site. We welcome > >any input you would like to share with us. We have linked an on-line > >comment form to the module, or you can send comments via direct e-mail > >to "module@.....................". > > > >We hope you enjoy your tour through the module. After the journey, we trust > >that you will be able to save at least some of the residents of Pinevale! > > > >Sincerely, > > > >John Marquis, Katrin Hafner and Egill Hauksson > >Caltech Seismological Lab > >Pasadena, CA 91125 _____________________________________________________________________ Public Seismic Network Mailing List (PSN-L) From: Brett Nordgren Subject: STM-8 loop analysis Date: Wed, 04 Nov 1998 20:46:06 -0500 To all: Just finished a major update of "loop2.pdf". Now have the loop gain, and response functions computed and plotted. Was pleased to see that the response agrees with S-T Morrissey's MathCad analysis quite well. Now it's starting to get interesting. Available at: http://members.home.net/nordgren/public/ Brett Nordgren _____________________________________________________________________ Public Seismic Network Mailing List (PSN-L) From: Norman Davis WB6SHI Subject: Re: Telemetry Decode Date: Wed, 04 Nov 1998 18:00:46 At 07:27 PM 11/4/98 -0400, you wrote: >Does anybody know where I can find software that will allow me to decode >USGS telemetry received from a scanner into my sound card (if such a >thing exists)? fftdsp runs continuously but will decode multiple channels. Check my web page under meteors and you will find a link to larry cooks page where the software can be had. Norman Davis WB6SHI Shingle Springs, Ca normd@............. http://www.directcon.net/normd/index.htm _____________________________________________________________________ Public Seismic Network Mailing List (PSN-L) From: meredith lamb Subject: Well done John Lahr Date: Wed, 04 Nov 1998 20:50:33 -0800 John Lahr wrote: > > > I have a draft version of my "Table-Top Earthquakes" demo on the > web now, and would love to get feedback for corrections, improvements, > etc. The URL is: http://giseis.alaska.edu/lahr/tabletop/ > > Cheers, > JCLahr > ################################## John C. Lahr > ################################# Seismologist I think your title should include passionate educator. I also think most of the URL subjects on the site were originated by yourself. I use your arrival time calculator all the time, and all the other subjects on the site are all very interesting. I'am guessing, but I think your internet activities have stirred the interests of countless thousands of visitors; let alone the extensive person to person activities you have had up in Alaska. Well done John Lahr! Meredith Lamb _____________________________________________________________________ Public Seismic Network Mailing List (PSN-L) From: barry lotz Subject: Re: ISA CARD FIX Y-2K Date: Wed, 04 Nov 1998 20:02:20 -0800 Dan Yeh. That's where I saw it. Thanks for jaring my mind.-- JDR Microdevices. Barry Dan wrote: > The ISA card for y2k fix was in this months sale paper, from -- I think > the name was either j&r or J&D micro divice in sunnvale ca.. it sold for > 29.95. > in you need the address i will try to find the add. > my wife says i never throw anything away > Dan > - _____________________________________________________________________ Public Seismic Network Mailing List (PSN-L) From: "james dunn" Subject: List of world wide quakes Date: Wed, 4 Nov 1998 22:59:16 -0500 To whom it may concern, I recently read an e-mail from Wayne Abraham, of Nov 2, 1998, from the island of Dominica, in the Caribbean, approx 15 deg north Lat., 67 deg west Long. He referred to numerous tremours from the volcanoes in the southern end of the island. Yet when I looked at the list of quakes world wide, on your web site, I did not see any quakes on the list. Why? I tried to send this message from your response page, but was unable to do so, so I elected to use this route. James R. Dunn Pensacola, Florida, USA temporarily in Kalamazoo, Michigan _____________________________________________________________________ Public Seismic Network Mailing List (PSN-L) From: barry lotz Subject: Re: Telemetry Decode Date: Wed, 04 Nov 1998 20:16:45 -0800 Norman I have used one called Gram 32 or Gram23. It records from a sound card and displays the frequency content vs time. It is quite useful. Barry Norman Davis WB6SHI wrote: > At 07:27 PM 11/4/98 -0400, you wrote: > >Does anybody know where I can find software that will allow me to decode > >USGS telemetry received from a scanner into my sound card (if such a > >thing exists)? > > fftdsp runs continuously but will decode multiple channels. Check my web > page under meteors and you will find a link to larry cooks page where the > software can be had. _____________________________________________________________________ Public Seismic Network Mailing List (PSN-L) From: Edward Cranswick Subject: Re: Well done John Lahr Date: Wed, 04 Nov 1998 22:30:15 -0700 John- I also think that your open-file is excellent and would recommend that you expand it to include strong motion by doing an experiment with a horizontal sensor mounted on the brick and oriented to be sensitive to motions in the direction of sliding. -Edward meredith lamb wrote: > John Lahr wrote: > > > > > > > I have a draft version of my "Table-Top Earthquakes" demo on the > > web now, and would love to get feedback for corrections, improvements, > > etc. The URL is: http://giseis.alaska.edu/lahr/tabletop/ > > > > Cheers, > > JCLahr > > ################################## John C. Lahr > > ################################# Seismologist > > I think your title should include passionate educator. I also think > most of the URL subjects on the site were originated by yourself. > I use your arrival time calculator all the time, and all the other > subjects on the site are all very interesting. I'am guessing, but > I think your internet activities have stirred the interests of > countless thousands of visitors; let alone the extensive person to > person activities you have had up in Alaska. > > Well done John Lahr! > > Meredith Lamb > > _____________________________________________________________________ > > Public Seismic Network Mailing List (PSN-L) > > To leave this list email listserver@............. with the body of the > message: leave PSN-L -- Edward Cranswick Tel: 303-273-8609 US Geological Survey, MS 966 Fax: 303-273-8600 PO Box 25046, Federal Center cranswick@........ Denver, CO 80225-0046 USA E.M. Forster said, "Only connect". _____________________________________________________________________ Public Seismic Network Mailing List (PSN-L) From: Ian & Liz Subject: dt2801 support/info Date: Wed, 04 Nov 1998 19:55:34 -1000 I recently bought a Data Translation dt2801 a/d board (without manual), and wondered if anyone else is using this board. I need to get the pin-out diagram of the i/o connector. I'd also be interested in any software to drive this board. There is example software on DT's site, but the examples don't seem to show how to change the input voltage range. Will EMON ever support this device? Any info would be appreciated. TIA Ian Smith _____________________________________________________________________ Public Seismic Network Mailing List (PSN-L) From: Stephen & Kathy Subject: Re: DI-150RS limitations Date: Wed, 04 Nov 1998 22:17:50 -0800 John Lahr wrote: > > I have a draft version of my "Table-Top Earthquakes" demo on the > web now, and would love to get feedback for corrections, improvements, > etc. The URL is: http://giseis.alaska.edu/lahr/tabletop/ > > Cheers, > JCLahr Hi John, I too use your arrival time calc and your site for my personal education! I was wondering if you could share an explination as to why the mag vs energy tables have changed so significantly from a few months ago??? They used to show a mag 4 as 15 tons of TNT and a mag 6 as 15,000 tons!! They now show 1,000 tons and 1,000,000 tons!! Was the old table that far off?? Or as is usually the case, did I cross something up somewhere,, again?? Thanks in advance and keep up the good work!! Stephen Mortensen PSN Station # 55 near Pilot Hill Ca. _____________________________________________________________________ Public Seismic Network Mailing List (PSN-L) From: Pete Subject: Re: dt2801 support/info Date: Wed, 04 Nov 1998 22:25:52 -0800 Ian, Let me know if you have any success? I have the DT2801-A, I called Data Translation, they wanted $50 for the manual! I have not done much with the board as I don't know the pinout? Thanks, Pete Fleming Ian & Liz wrote: > I recently bought a Data Translation dt2801 a/d board (without manual), and > wondered if anyone else is using this board. > > I need to get the pin-out diagram of the i/o connector. I'd also be > interested in any software to drive this board. There is example software on > DT's site, but the examples don't seem to show how to change the input voltage > range. > > Will EMON ever support this device? > > Any info would be appreciated. > > TIA > > Ian Smith > > _____________________________________________________________________ > > Public Seismic Network Mailing List (PSN-L) > > To leave this list email listserver@............. with the body of the > message: leave PSN-L _____________________________________________________________________ Public Seismic Network Mailing List (PSN-L) From: Larry Cochrane Subject: Re: PSN - SDR Question? Date: Thu, 05 Nov 1998 00:08:38 -0800 Rex, As Karl points out your min / max seems a bit high. The 16 bit A/D chip I use is spec'ed at an internal noise level of +- 3 bits. This is why I have a note on the A/D card web page about the 16 bit version having a 10X dynamic range over the 12 bit version. The theocratical dynamic range improvement should be 16X. Depending on the location to other boards and the type of computer you are using, your mileage may very... As an example; A 16 bit A/D board placed in an old 486 system will have +-3 to +-4 counts of "background noise" when the inputs are shorted. The same card placed in a 75 Mhz Pentium system will have an extra +- 2 to +-3 bits of noise. I am run into this problem with my "day job". We are doing some contract work on a DSL modem, a new higher digital link into the Internet (more about DSL in an upcoming email...). We have a high speed 16 bit D/A converter card made by National Instruments. We are using the D/A convert as a DSL transmitter on this system, a 233Mhz Pentium. We have another computer system with another A/D card, a Datel 14 bit high speed (5Meg SPS) A/D converter, in it that is acting as a DSL receiver. We are having dynamic range problems... We looked at the output of the 16 bit D/A card, with a scope, and there is almost +-10mv of noise coming out of the card! The card produces +-10 volts max so each bit should be around 300uv. The computer with the A/D card in it (14 bits) also has problems. This system is a 400Mhz Pentium II and the number of background noise counts, with the input shorted, is around +-4 counts so it is no better than a 12 bit card. So for a data logging system an old 486 system works better than an a newer high speed Pentium system. Also, keep the number of other cards in the system down to a minimum. -Larry Cochrane Redwood City, PSN At 08:23 AM 11/4/98 -0800, you wrote: >At 07:10 PM 11/3/98 -0500, you wrote: >>I have just installed my SDR acquisition board (16 bit) into my system >>and now in the process of 'playing'. I have one question. When I place >>a very short jumper between an analog input and analog ground right at >>the plug on the card I would expect to see 0 counts or very close to 0. >>What I do see is a signal that ranges from +3 to -15 or -16 counts using >>the max/min function on the analog count output display. Is this a >>problem? It seems that I have lost the difference between the 12 bit >>and the 16 bit adc! > >Rex -- > >That noise level sounds a little high compared to what I see, but not too >much different. My noise level using just the A/D card runs between +5 to >-5 counts -- about 10 counts total. You can use the zero offset function >in SDR to make your noise symmetrical around zero. You might try plugging >the A/D card into a different slot in the computer. I found that the >least-noisy slot was the one farthest from the hard disk (closest to the >side panel of the enclosure). Also move other plug-in cards as far away >from the A/D card as you can. > >Some noise level is normal. I looked up the specs on the A/D chip and >found that +/- 3 to 5 counts is not unusual. It's too bad that a chip >manufacturer makes a 16-bit part that has such a noise level that makes the >last 2-3 bits unusable without averaging. > >I wonder if there is a better chip that could be used (perhaps for more $) >without circuit or software changes. Larry may have looked into this. > > >Karl Cunningham >La Mesa, CA. >PSN station #40 >karlc@....... > >_____________________________________________________________________ > >Public Seismic Network Mailing List (PSN-L) > >To leave this list email listserver@............. with the body of the >message: leave PSN-L > _____________________________________________________________________ Public Seismic Network Mailing List (PSN-L) From: Edward Cranswick Subject: Re: PSN - SDR Question? Date: Thu, 05 Nov 1998 02:57:29 -0700 Larry- That's awful. Larry Cochrane wrote: > ... As an example; > A 16 bit A/D board placed in an old 486 system will have +-3 to +-4 counts > of "background noise" when the inputs are shorted. The same card placed in > a 75 Mhz Pentium system will have an extra +- 2 to +-3 bits of noise. > Some things never change. We had these kind of A/D noise problems on the 12-bit systems I first used in 1980. I then thought that they would soon be swept by new technologies, but they have only been enhanced. Making a quiet analog system is an art that must first be accomplished before the Hi-Tech digital leap of faith.-Edward -- Edward Cranswick Tel: 303-273-8609 US Geological Survey, MS 966 Fax: 303-273-8600 PO Box 25046, Federal Center cranswick@........ Denver, CO 80225-0046 USA E.M. Forster said, "Only connect". _____________________________________________________________________ Public Seismic Network Mailing List (PSN-L) From: Werner Wesling Subject: Re: dt2801 support/info Date: Thu, 05 Nov 1998 14:02:57 +0100 I guess have documentation and s/w for dt2801. I will look for it the next days. When I find it i can send you the info you need. Werner At 06:55 05.11.98 +0100, you wrote: >I recently bought a Data Translation dt2801 a/d board (without manual), and >wondered if anyone else is using this board. > >I need to get the pin-out diagram of the i/o connector. I'd also be >interested in any software to drive this board. There is example software on >DT's site, but the examples don't seem to show how to change the input voltage >range. ---------------------------------------------- Dipl.Ing. Werner Wesling DASA Raumfahrt-Infrastruktur Abtlg. RIO52 Postfach 28 61 56 Phone +49 421 539-5218 28361 Bremen Fax +49 421 539-5127 Deutschland werner.wesling@.......... ---------------------------------------------- _____________________________________________________________________ Public Seismic Network Mailing List (PSN-L) From: Roger Sorensen Subject: Re: dt2801 support/info Date: Thu, 05 Nov 1998 07:41:35 -0800 I have a JPG file (749k) of the Pin Out Table. If anyone would like it e-mailed to them, drop me a note. Let me know if you want it Zipped or not. Roger roger.sorensen @ worldnet.att.net (take out the spaces) Ian & Liz wrote: > > I recently bought a Data Translation dt2801 a/d board > > I need to get the pin-out diagram of the i/o connector. _____________________________________________________________________ Public Seismic Network Mailing List (PSN-L) From: John Lahr Subject: Re: dt2801 support/info Date: Thu, 5 Nov 1998 09:09:31 -0700 (MST) There is some IASPEI* software based on the dt2821 a/d board: Lee, W.H.K. (Editor). IASPEI Software Library, Seismological Society of America, El Cerrito, CA, U.S.A., v. 1-5, 1989-1993. See: http://www.seismosoc.org/htdocs/publications.html#software You would need Volume 1 and Volume 2 for a total of $250, plus $100 to become a member of the Seismological Society of America. That's quite a bit, but the software is quite nice. Apart from sismic data inputs, you would want to digitize an IRIG-E time code on one channel. This would give you 15 data channels and one time channel. *International Association of Seismology and Physics of the Earth's Interior This is clearly not an inexpensive route to take... maybe someday the software price will come down. JCLahr > From psn-l-return@.............. Wed Nov 4 22:59 MST 1998 > > I recently bought a Data Translation dt2801 a/d board (without manual), and > wondered if anyone else is using this board. > > I need to get the pin-out diagram of the i/o connector. I'd also be > interested in any software to drive this board. There is example software on > DT's site, but the examples don't seem to show how to change the input voltage > range. > > Will EMON ever support this device? > > Any info would be appreciated. > > TIA > > Ian Smith > > _____________________________________________________________________ Public Seismic Network Mailing List (PSN-L) From: John Lahr Subject: Re: TNT vs EQ magnitude Date: Thu, 5 Nov 1998 09:29:24 -0700 (MST) Hi Stephen, From chemical considerations one can find the amount of energy released per pound of TNT. There is also research that gives an equation for the amount of seismic energy radiated by an earthquake of a given magnitude. It was on this basis that I generated the earlier tables, and it leads to 15 ton of TNT generates the same energy as a magnitude 4 earthquake. However, in the field of bomb vs earthquake discrimination, empirical comparisons of the seismic waves generated by bombs and chemical explosions have been made. This work finds that it takes 1,000 tons of TNT to generate seismic waves that look like a magnitude 4 earthquake. As far as I can understand, this is based on two factors. One, the TNT generates a lot of heat and light that do not contribute to the ground motion, but are counted in the total energy released. And two, an explosion is nearly a point source, whereas an earthquake ruptures over the surface area of the fault. I hate to get into the issue of different magnitude scales, but the 1,000 tons for a magnitude 4 refers to the body wave magnitude, mb. This is a high frequency measure of the earthquake, based on the P-phase arrival. The 20-second surface wave magnitude of 1,000 tons even smaller than 4, because an explosion is a poor source of low frequency waves. There are probably seismologists on this list who can improve on this explanation. If so, please have at it! Cheers, JCLahr > Date: Wed, 04 Nov 1998 22:17:50 -0800 > From: Stephen & Kathy > > ... I was wondering if you could share an explination > as to why the mag vs energy tables have changed so significantly > from a few months ago??? They used to show a mag 4 as 15 tons of > TNT and a mag 6 as 15,000 tons!! They now show 1,000 tons and > 1,000,000 tons!! Was the old table that far off?? Or as is > usually the case, did I cross something up somewhere,, again?? > Thanks in advance and keep up the good work!! > Stephen Mortensen _____________________________________________________________________ Public Seismic Network Mailing List (PSN-L) From: John Lahr Subject: Re: dt2801 support/info Date: Thu, 5 Nov 1998 10:01:46 -0700 (MST) Ian, The E version is a "fast" time code that requires only 10 seconds of signal for a full decode of the time. Doesn't the "B" code require 60 seconds for a full decode? On GPS time receivers, "IRIG-E" may be an available option. It was for the TrueTime GPS receiver we used in Fairbanks. JCLahr > From macsmith@......... Thu Nov 5 09:29 MST 1998 > ... You mention IRIG-E, I use > the "B" version at work from gps receivers, I'm just wondering what the "E" version > is, and how it is received. > > Thanks. > > Ian > > > _____________________________________________________________________ Public Seismic Network Mailing List (PSN-L) From: meredith lamb Subject: Re: PSN - SDR Question? Date: Thu, 05 Nov 1998 11:05:30 -0800 Larry Cochrane wrote: > Rex, > > So for a data logging system an old 486 system works better than an a newer > high speed Pentium system. Also, keep the number of other cards in the > system down to a minimum. > > -Larry Cochrane > Redwood City, PSN > Larry, Any brand name preferences come to mind? Or....what do you use, and/or what do you wish you used instead? Obviously, people usually don't have a choice with whats available, but sometimes it would pay in the long run to have a more reliable brand in use, than putting up with some brands that consistently are less enduring. I also realize that preferences are often guided by ones experience, so....it would likely just be an opinion. Anyway....if an old 486 could fit the A/D-SDR "bill", this is really good news, as their would seem to be alot more of these available and likely alot cheaper by far than pentium models; with the premise that the specific prospect model actually works before buying. (The following is my relatively inexperienced yak on the subject for interested people)-ha. Also, the operating system on board would have to come under consideration with its space hogging aspects, as older 486's usually have less than 500 meg drives. Perhaps an older Windows system would be better. Won't get into a IBM compatible versus Macintosh choice brew......but reality is, that there are alot more IBM compatibles around. Any prospective (working) computer would have to be big enough to hold the (Internal) A/D card of choice, so, it would also pay to have the card on hand, or, knowing its size, and whether it would fit therein before purchase, and that their is a compatible slot available and/or the cards can be either rearranged or dumped and still have it work.... 1. Is it big enough to hold the card? Check inside. 2. If you don't have the model experience, you may really need the manuel for help, if you don't have zilch experience. The jumpers may have to be re-arranged, and, perhaps a sound card/game card may have to be dumped for room. Even if you do have experience, you may forget...you need the model manuel that does show the specific jumpers, switches, do this, do that before, and etc. Don't depend on getting a manuel from the company....99% won't even have it available. No manuel with specfics; no purchase. 3. Does it actually work now...before conversion? It maynot work after installation, and you may need an experienced friends help for problem resolution. If you get it from a used computer place, perhaps they can install it for a reasonable fee, but even here, they likely won't be cheap, but the risk is that there likely won't be a guarantee of success. 4. Get the help and or experience or manuel info down pat. You do want to succeed. Suggest all 4 of the above, or you maybe stuck with a foot/cat/ dog warmer, or "pet rock" of no value. Yes...it took me over a week to get mine going, along with alot of mistakes-ha. After purchase, use a outlet with a ground connection, otherwise it will do the zap/shutdown dance from static electricity perhaps too often. Meredith Lamb _____________________________________________________________________ Public Seismic Network Mailing List (PSN-L) From: Edward Cranswick Subject: PSN meeting Date: Thu, 05 Nov 1998 17:47:05 -0700 Larry- Probably the best thing would be to schedule the PSN meeting for either Saturday, 5 Dec or Saturday, 12 Dec. My PSN poster and Sean-Thomas' VBB poster are in the same AGU session on Sunday, 6 Dec; Ted&Jan's and John Tabor's PSN posters are in the same AGU session on Thursday, 10 Dec. I may be able to arrange to hold the PSN meeting again, like last year, at the USGS, Menlo Park, CA. -Edward Larry Cochrane wrote: > Ok... Do you think we should schedule another PSN meeting around then??? -- Edward Cranswick Tel: 303-273-8609 US Geological Survey, MS 966 Fax: 303-273-8600 PO Box 25046, Federal Center cranswick@........ Denver, CO 80225-0046 USA E.M. Forster said, "Only connect". _____________________________________________________________________ Public Seismic Network Mailing List (PSN-L) From: Larry Cochrane Subject: Re: PSN - SDR Question? Date: Thu, 05 Nov 1998 20:22:54 -0800 At 11:05 AM 11/5/98 -0800, Meredith wrote: >Any brand name preferences come to mind? Or....what do you >use, and/or what do you wish you used instead? I usually don't buy brand name PC's. I go to a small computer shop that I have been going too for years. They sell mostly OEM boards and build up the systems for their costumers. > >Also, the operating system on board would have to come under >consideration with its space hogging aspects, as older 486's >usually have less than 500 meg drives. Perhaps an older Windows >system would be better. If the system is for data logging, SDR and EMON are DOS programs, so the operating system size shouldn't be a problem. -Larry _____________________________________________________________________ Public Seismic Network Mailing List (PSN-L) From: Larry Cochrane Subject: Northern California PSN meeting in December Date: Thu, 05 Nov 1998 21:23:28 -0800 Edward and other PSN'ers, Since Sean-Thomas and John Tabor will be attending the AGU, maybe we can arrange a date and time when both could attend, if they are interested? Also, how many local (and other list members, if they can attend) would like to have a meeting around the time of the AGU? Having the meeting at the Menlo Park USGS would be great. -Larry Cochrane Redwood City, PSN At 05:47 PM 11/5/98 -0700, Edward Cranswick wrote: >Larry- > Probably the best thing would be to schedule the PSN meeting for either >Saturday, 5 Dec or Saturday, 12 Dec. My PSN poster and Sean-Thomas' VBB poster are >in the same AGU session on Sunday, 6 Dec; Ted&Jan's and John Tabor's PSN posters >are in the same AGU session on Thursday, 10 Dec. I may be able to arrange to hold >the PSN meeting again, like last year, at the USGS, Menlo Park, CA. >-Edward > >Larry Cochrane wrote: > >> Ok... Do you think we should schedule another PSN meeting around then??? > >-- >Edward Cranswick Tel: 303-273-8609 >US Geological Survey, MS 966 Fax: 303-273-8600 >PO Box 25046, Federal Center cranswick@........ >Denver, CO 80225-0046 USA E.M. Forster said, "Only connect". > > > _____________________________________________________________________ Public Seismic Network Mailing List (PSN-L) From: Karl Cunningham Subject: Re: Northern California PSN meeting in December Date: Fri, 06 Nov 1998 08:49:59 -0800 At 09:23 PM 11/5/98 -0800, Larry wrote: >Also, how many local (and other list members, if they can attend) would >like to have a meeting around the time of the AGU? > >Having the meeting at the Menlo Park USGS would be great. Larry, and others -- I'd love to attend a meeting. Since it's around the holidays, the time of AGU is not the best for me, I could probably swing it. Karl Cunningham La Mesa, CA. PSN station #40 karlc@....... _____________________________________________________________________ Public Seismic Network Mailing List (PSN-L) From: Larry Cochrane Subject: DSL Internet Connection for the Redwood City PSN Site Date: Sat, 07 Nov 1998 19:51:20 -0800 All, A few days ago I ordered a DSL, Digital Service Line, connection into the Internet for my computer systems here at home. As most of you know, I currently have a dedicated (24/7) 28K (connects at 26.4Kbs most of the time) modem phone line connection to my ISP for my web, ftp and email servers at http://psn.quake.net. PacBell, my local phone company, is offering a DSL connection at a price that is only a little more per month than what I am currently paying to my ISP for my 28k connection. PacBell offers different packages with different connection speeds and number of static IP address. I'm starting out with the lowest (read cheapest) connection speed, 128K outgoing and 384k incoming and 5 IP address. The new cost will be $139.00 per month, I'm currently paying $105.00 per month. Startup costs is $500.00, about the same amount I paid several years ago when I got my dedicated 28k modem connection. There is one problem. I'm also changing my ISP. I'm currently using a small ISP called QuakeNet and my DSL line will use PacBell. PacBell, besides operation the point to point connection, can be the ISP. You can choose other ISPs for the DSL connection, but I thought it would be best too keep it within PacBell. Since I will be changing ISP's, I may loose the psn.quake.net domain name. I will see if QuakeNet will keep the psn. part of their domain name (quake.net) for me, but point it to my new IP address that PacBell will be giving me. My current ISP will probably want to charge some fee to do this. The problem is I get email coming to psn.quake.net and all of the search engines have http://psn.quake.net/... in their databases. I have two domain names allocated to me. One is webtronics.com and the other is seismicnet.com. I can create psn.webtronics.com and / or psn.seismicnet.com (or www.seismicnet.com) domain names, that's not a problem. Hopefully QuakeNet will keep forwarding email sent to *@............. and forward the IP address needed so that http://psn.quake.net keeps working without charging too much. The new connection should be installed on Tuesday (11/10). If everything goes well, I should have the Redwood City PSN site on line using the webtronics.com and seismicnet.com domain names later that night using the new higher speed connection. Regards, Larry Cochrane Redwood City, PSN _____________________________________________________________________ Public Seismic Network Mailing List (PSN-L) From: taber@............. (John Taber) Subject: Re: Northern California PSN meeting in December Date: Mon, 9 Nov 1998 10:29:07 +1300 Edward, Larry, et al I'd love to come to a PSN meeting while I'm in San Francisco, though the time I'm in California may not work for others. I arrive Saturday 5 December at 3:15 so I could make a late afternoon/evening meeting that day at Menlo Park. I could also come any evening during the week and I leave at 4 PM on Friday 11 Dec. John Taber _____________________________________________________________________ Public Seismic Network Mailing List (PSN-L) From: "David A. Nelson" Subject: MAJ QUAKE in progress Date: Mon, 9 Nov 1998 19:01:58 +1300 05:45 UTC 09 nov 98 5000+ dps on SDR large S and Surface waves DAve Co-ordinator: New Zealand Public Seismic Network Dave A. Nelson ZL4TBN 24 Jensen St., Green Is., Dunedin, South Is.. New Zealand. http://psn.quake.net/dave/home.htm IF there indeed are other parallel universes... I can now rest in the knowledge, that in at least one of them, I am filthy rich and drive a red Ferrari _____________________________________________________________________ Public Seismic Network Mailing List (PSN-L) From: meredith lamb Subject: Re: MAJ QUAKE in progress Date: Sun, 08 Nov 1998 23:15:44 -0800 "David A. Nelson" wrote: > 05:45 UTC 09 nov 98 > > 5000+ dps on SDR large S and Surface waves > > DAve > > Co-ordinator: > New Zealand > Public Seismic Network > Dave A. Nelson ZL4TBN > 24 Jensen St., > Green Is., Dunedin, > South Is.. New Zealand. > > http://psn.quake.net/dave/home.htm > Dave, See it rolling in here also. Long period everything; maybe on your side of the world? Guess we'll find out. Meredith Lamb _____________________________________________________________________ Public Seismic Network Mailing List (PSN-L) From: Ian & Liz Subject: adding an a/d to emon Date: Sun, 08 Nov 1998 20:22:04 -1000 Hi, Does anyone know how easy would it be to add support for an extra a/d card to Emon? I have a Data Translation DT2801. Thanks Ian Smith _____________________________________________________________________ Public Seismic Network Mailing List (PSN-L) From: Canie Brooks Subject: Re: MAJ QUAKE in progress Date: Sun, 08 Nov 1998 22:43:29 -0800 Just found this: 09Nov1998 05:38:46.7 6.4S 128.7E 33 mb=6.2 A*NEI BANDA SEA on page: http://seismo.ethz.ch/redpuma/redpuma_ami_list.html Canie At 11:15 PM 11/8/98 -0800, meredith lamb wrote: > > >"David A. Nelson" wrote: > >> 05:45 UTC 09 nov 98 >> >> 5000+ dps on SDR large S and Surface waves >> >> DAve >> >> Co-ordinator: >> New Zealand >> Public Seismic Network >> Dave A. Nelson ZL4TBN >> 24 Jensen St., >> Green Is., Dunedin, >> South Is.. New Zealand. >> >> http://psn.quake.net/dave/home.htm >> > >Dave, > >See it rolling in here also. Long period everything; maybe on your >side of the world? Guess we'll find out. > >Meredith Lamb > > > > >_____________________________________________________________________ > >Public Seismic Network Mailing List (PSN-L) > >To leave this list email listserver@............. with the body of the >message: leave PSN-L > _____________________________________________________________________ Public Seismic Network Mailing List (PSN-L) From: barry lotz Subject: Re: MAJ QUAKE in progress Date: Sun, 08 Nov 1998 22:48:51 -0800 Dave Picking it up here in Calif also. Barry David A. Nelson wrote: > 05:45 UTC 09 nov 98 > > 5000+ dps on SDR large S and Surface waves > > DAve > _____________________________________________________________________ Public Seismic Network Mailing List (PSN-L) From: "J. D. Cooley" Subject: Re: MAJ QUAKE in progress Date: Mon, 09 Nov 1998 02:34:46 -0800 At 10:43 PM 11/8/98 -0800, you wrote: > >Just found this: >09Nov1998 05:38:46.7 6.4S 128.7E 33 mb=6.2 A*NEI BANDA SEA > >on page: >http://seismo.ethz.ch/redpuma/redpuma_ami_list.html > >Canie > Later updated to: 09Nov1998 05:38:44.5 6.8S 128.7E 33 MS=7.0 M*NEI BANDA SEA A BIG one! "JD" >At 11:15 PM 11/8/98 -0800, meredith lamb wrote: >> >> >>"David A. Nelson" wrote: >> >>> 05:45 UTC 09 nov 98 >>> >>> 5000+ dps on SDR large S and Surface waves >>> >>> DAve >>> >>> Co-ordinator: >>> New Zealand >>> Public Seismic Network >>> Dave A. Nelson ZL4TBN >>> 24 Jensen St., >>> Green Is., Dunedin, >>> South Is.. New Zealand. >>> >>> http://psn.quake.net/dave/home.htm >>> >> >>Dave, >> >>See it rolling in here also. Long period everything; maybe on your >>side of the world? Guess we'll find out. >> >>Meredith Lamb >> >> >> >> _____________________________________________________________________ Public Seismic Network Mailing List (PSN-L) From: wizard@......... (Rick Jerome) Subject: Re: Telemetry Decode Date: Mon, 9 Nov 1998 13:13:33 -0800 New update to GRAM is available at; http://www.monumental.com/rshorne/gram.html Some nice new features. Still waiting for a way to trigger a save. ---------- > From: barry lotz > To: PSN-L Mailing List > Subject: Re: Telemetry Decode > Date: Wednesday, November 04, 1998 8:16 PM > > Norman > I have used one called Gram 32 or Gram23. It records from a sound card > and displays the frequency content vs time. It is quite useful. > Barry > > > Norman Davis WB6SHI wrote: > > > At 07:27 PM 11/4/98 -0400, you wrote: > > >Does anybody know where I can find software that will allow me to decode > > >USGS telemetry received from a scanner into my sound card (if such a > > >thing exists)? > > > > fftdsp runs continuously but will decode multiple channels. Check my web > > page under meteors and you will find a link to larry cooks page where the > > software can be had. > > > _____________________________________________________________________ > > Public Seismic Network Mailing List (PSN-L) > > To leave this list email listserver@............. with the body of the > message: leave PSN-L _____________________________________________________________________ Public Seismic Network Mailing List (PSN-L) From: S-T Morrissey Subject: VBB loop response, etc Date: Mon, 9 Nov 1998 20:50:41 -0600 (CST) Brett, I looked at your figures. Nicely done. (I haven't looked at your previous ones because I was unsure if we could read .pdf. But we can with acrobat, which loads as a plugin. Regarding the enhancement of the loop gain at lower frequencies: Steim thought it was necessary, and added it at the output of the displacement detector, as you have suggested. He called it an "inverse filter" in his thesis, but it was actually suggested by Wielandt in 1970. The main purpose is to desensitize the closed- loop response to changes in the mechanical system like damping and free period, which changed by as much as 1/2 to 1%. In practicality this means that the additional LP gain of the loop allows the response to be more tightly controlled by the feedback parameters at long periods without having so much gain (controlled by the "r" value) at short periods that it is unstable and oscillates. However, as your figures show, the change is not enough to grossly change the overall response. In the VBB designs, the filter period is that of the seismometer, 20 or 360 seconds. In your figure, the LP corner is considerably longer than the seis period of 90 seconds. The original VBBs at Harvard did not have the filter installed. I have implemented a different filter as a two pole filter at the output of the VRDT demodulator of 0.47uf with 20k ohms, and a second pole at 1 second in the displacement gain amplifier. Without it the seis audibly humms at about 200 hz. This is not quite the very long period corner that is the inverse filter, but is more in line with keeping Td (the displacement transducer time constant) small enough to avoid phase problems. Td should be less than Rf*C. I actually determined the filter by experiment, mainly trying to maintain adequate short period gain in the data passband without the loop oscillating. (This is some of the "between the lines" documentation I need to complete.) I could try this filter by modifying the displacement gain amp to see if the effect is perceptible in the calibration. But it is probably not necessary since the calibrations do fit the transfer function quite well. But I wonder how it will effect the very long period stability and sensitivity to pressure and tilt (of the horizontal). This might make it worth implementing.. Another parameter I have ignored is the Bo (mechanical damping) of the seis. It is considerable, mostly because of the close fit between the coil and the magnet gap. Also, the aluminum coil form, while not being a closed loop, is providing some eddy current damping. The main effect is that the mechanical Q is low. Regarding the temperature problem, I can only observe that it IS everywhere, However, all my calculated estimates of it come out at only about 10% of the observed effect, and gentle heating of things like the VRDT don't produce anywhere near the effect of any heating of the leaf spring, which you can warm up appreciably just by shining a strong lantern type flashlight on it. (The bimetallic temp comp coil can be similarly tested by shining only a small penlight on it. In fact, one could possibly control the brightness of such a lamp with the position error voltage so as to provide active temperature compensation.) Regards, Sean-Thomas _____________________________________________________________________ Public Seismic Network Mailing List (PSN-L) From: meredith lamb Subject: 1908 Tunguska atmospheric explosion web site Date: Mon, 09 Nov 1998 21:17:50 -0700 If you're interested, I made a web site question as to the 1908 Tunguska meteor/comet explosion; as to to actually seeing a seismogram of the event, awhile back. Curiosity thing. A fellow named Andrei E. Zlobin made reference to this site for acouple seismograms, barograms and magnetogram: http://www.orc.ru/~azorcord/page_dat.htm Meredith Lamb -- Meredith Lamb <><><><><><><><><><><><><><><><><><><><><><><><><><><><><><><><><><><><> Main Web site: http://www.users.uswest.net/~psnseismograph52/Index.html <><><><><><><><><><><><><><><><><><><><><><><><><><><><><><><><><><><><> _____________________________________________________________________ Public Seismic Network Mailing List (PSN-L) From: rayv Subject: seismic base material Date: Tue, 10 Nov 1998 18:23:33 -0500 i remember reading an e-mail which indicated someone had a source for granite or stone base material. i cannot find the e-mail. could someone point me to the source? i have looked over the subjects of the previous e-mails and it must be buried in a message some where. thanks. _____________________________________________________________________ Public Seismic Network Mailing List (PSN-L) From: John Hernlund Subject: Re: seismic base material Date: Tue, 10 Nov 1998 17:31:43 -0700 (MST) On Tue, 10 Nov 1998, rayv wrote: > i remember reading an e-mail which indicated someone had a source for > granite or stone base material. i cannot find the e-mail. could someone > point me to the source? i have looked over the subjects of the previous > e-mails and it must be buried in a message some where. There are always lots of cemetaries around... Just kidding. Check with local quarries and rock suppliers; they are, of course, heavy to ship from out of town. ****************************************************************************** John Hernlund E-mail: hernlund@....... WWW: http://www.mc.maricopa.edu/academic/phy_sci/Geology/hernlund/ http://www.public.asu.edu/~hernlund/ ****************************************************************************** _____________________________________________________________________ Public Seismic Network Mailing List (PSN-L) From: S-T Morrissey Subject: seismic piers Date: Tue, 10 Nov 1998 18:59:04 -0600 (CST) An adequate source of pier material that won't break your back and your wallet is concrete blocks and patio pavers. They are easy to handle and allow a flexible design, and are cemented to the floor and to each other with ordinary floor tile grout. A smooth top surface is made by grouting on 12 x 12" glazed tiles. An alternate plan is to form up and pour a solid concrete pier; but do not use any rebar or steel mesh. Plain "sacrete" will do. We just upgraded the pier at a station near Nashville (WVT) by having the contractor dig a 6' x 8' x 5' deep pit in the floor (the original pier) and fill it with 10 yards of concrete. If a single solid rock slab is used, it should be set with a sand-rich concrete or grout on top of the floor or an excavation in hard earth. The photos of the concrete block pier in my basement are at: http://www.eas.slu.edu/People/STMorrissey/index.html Regards, Sean-Thomas _____________________________________________________________________ Public Seismic Network Mailing List (PSN-L) From: Gary McCool Subject: Re: seismic base material Date: Tue, 10 Nov 1998 20:33:26 -0500 At 05:31 PM 11/10/98 -0700, you wrote: >On Tue, 10 Nov 1998, rayv wrote: >> i remember reading an e-mail which indicated someone had a source for >> granite or stone base material. i cannot find the e-mail. could someone >> point me to the source? i have looked over the subjects of the previous >> e-mails and it must be buried in a message some where. I believe the granite blocks you are looking for come from "discount" tool sources such as IPS, Harbor Freight, and Chicago tool. They are used as precision flat surfaces for inspection purposes. My IPS catalog lists a "B" grade as large as 8" x 36" X 48". They are in El Monte, CA at 800 423-4981. IPS has an even lower grade "B -0-Ledge" 18" x 24" for 139.95 (thickness unknown) in some of their flyers. Hope this helps... Gary McCool, a lurker with a Lehman Perkins Observatory, Delaware, Ohio _____________________________________________________________________ Public Seismic Network Mailing List (PSN-L) From: Karl Cunningham Subject: Re: seismic base material Date: Tue, 10 Nov 1998 17:38:44 -0800 Ray -- Here is something I wrote on the subject a few weeks ago. Companies that cut granite slabs for surface plates (and other things) sometimes have discards that they cannot use because of inclusions, cracks, etc. I saw one used by an amateur laser experimenter that was about 3' by 6' by 4" thick, weighed about 1000#, and it cost him about $100. The surface wasn't mirror smooth, but as good as a concrete floor. He was trying to isolate his apparatus from earth noise and thus supported the plate with inflated inner tubes. Presumably, setting such a plate in grout could do the opposite. Karl Cunningham La Mesa, CA. PSN station #40 karlc@....... At 06:23 PM 11/10/98 -0500, you wrote: >i remember reading an e-mail which indicated someone had a source for >granite or stone base material. i cannot find the e-mail. could someone >point me to the source? i have looked over the subjects of the previous >e-mails and it must be buried in a message some where. >thanks. _____________________________________________________________________ Public Seismic Network Mailing List (PSN-L) From: ralvarez@........ (Raul Alvarez) Subject: Re: seismic base material Date: Tue, 10 Nov 1998 18:52:02 -0700 (MST) I sent an e-mail some time ago about using 1-1/4 inch thick synthetic (sp) slate from lab table tops. I got some at a university auction. It's heavy! Have not actuall applied it to use yet. Raul >i remember reading an e-mail which indicated someone had a source for >granite or stone base material. i cannot find the e-mail. could someone >point me to the source? i have looked over the subjects of the previous >e-mails and it must be buried in a message some where. >thanks. > > >_____________________________________________________________________ > >Public Seismic Network Mailing List (PSN-L) > >To leave this list email listserver@............. with the body of the >message: leave PSN-L > > ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ "My dreams are the seeds of my reality, nurtured in the womb of my soul" RJA, 1985 Raul J. Alvarez La Estrellita Observatory Bellvue, Colorado e-mail ralvarez@........ homepage www.frii.com/~ralvarez "The Renaissance Experimenter" doing research in: Radio and Optical Astronomy, Seismology, Weather, Computers, Instrumentation and Neat Stuff! ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ _____________________________________________________________________ Public Seismic Network Mailing List (PSN-L) From: "Al Allworth" Subject: FW: Date: Tue, 10 Nov 1998 18:24:33 -0800 > -----Original Message----- > From: Al Allworth [mailto:allworth@............... > Sent: Thursday, October 15, 1998 11:16 PM > To: PSN-L Mailing List > Subject: Suggestion for seismo base > The URL should be http://www.ipstool.com Earlier this year there was a lot of discussion about suitable material for a stable pier for a seismometer mounting. About the same time I bought a granite surface plate but never thought at that time of using one for a pier surface. Granite is very stable and the prices of surface plates has really taken a dive with China now as a supplier. The one I bought was around $90.00. It is 18" x 24" x 3" and weighs 145 lbs. They also have one 12" x 18" x 3" at $30.00 and one 9" x 12" x 3" for $20.00. The surface accuracy is around 0.0001". The company I bought from is Industrial Pipe and Steel in El Monte, Calif. http://ipstool.com I think any machine shop supply company would have them. The American made ones sell for nearly 10 times these prices. Just a thought for those building piers. Al Allworth From: Brett Nordgren Subject: Re: VBB loop response, etc Date: Wed, 11 Nov 1998 09:29:55 -0500 Sean-Thomas, Just to avoid confusing the list, this thread is about some thoughts I'd had concerning the feedback loop, documented in http://members.home.net/nordgren/public/loopmods.pdf (That's not going to get put in the index page so it will have to be accessed directly by its file name.) It might be useful to quickly revisit why I made the suggestion, viewed strictly as a feedback problem. It wouldn't surprise me to hear a crusty old feedback designer complain that any system that doesn't have a loop gain greater than 100 just doesn't deserve to be called a feedback system. All the good rules of thumb depend on high loop gain. The useful approximations (the main one being that performance depends only on the feedback elements) are 99% accurate for loop gain = 100, are 90% accurate for loop gain = 10 and 50% accurate for a loop gain of 2. So, to satisfy the old designer, and gain being cheap, I set out to try to increase the low frequency loop gain. Adding an additional factor of 100 to the displacement amplifier gain looked reasonable. But to avoid creating oscillation problems, I didn't want my changes to affect the original loop much above 1 Hz. So I had to start bringing down the extra gain at 0.005 Hz and then flatten it out at 0.5 Hz, at which point the displacement amp gain is back down to its original value of 10. My intent with the filter was simply to get rid of the gain I'd added, before you got into a frequency region where I might be causing oscillation problems. Regarding the 200 hz hum you were seeing. I'll bet most anything that that it's another mechanical resonance. My reasoning is as follows: 1) the high-frequency loop gain is determined only by the mass and the displacement amp, whose values are well known. They predict gain crossover at about 37 hz. (see http://members.home.net/nordgren/public/ feedback.pdf and loop2.pdf) 2) Any changes to the displacement amp. that I wasn't considering would, if anything, reduce the gain crossover frequency. 3) The oscillation frequency is well above 37 Hz. That's the classic characteric of a high-frequency resonance since unstable loops should oscillate somewhat near their gain crossover frequency. You can imagine that there's a high-Q spike in the loop gain from a mechanical resonance at 200 Hz, which pokes back up above unity. That's a second gain crossover point, and one that has very bad (large lagging) phase. Guaranteed oscillator. If true, I don't know if it's good news or not. Resonances can be nasty to deal with, though there are a number of techniques (like attaching the mass through a rubber pad) that might help, depending on the source of the problem. More damping magnets on the spring? Trying to avoid the problem with poles in the displacement amp, always risks having oscillations somewhere below 37 Hz. One is caught between the two evils. Trying to reduce the height of the resonance, might be the easier line of attack. Really enjoyed hearing about your flashlight temperature testing. It's obvious that it's pretty sensitive. I need to think a lot more about these noise/drift things. Want to totally understand the loop, before digging in that direction. I'd be most interested in what you think. Brett _____________________________________________________________________ Public Seismic Network Mailing List (PSN-L) From: Gregory Bajuk Subject: Low noise signal cable Date: Wed, 11 Nov 1998 08:21:03 -0800 (PST) I has reading the manual provided with the Dataq DI-150RS a/d module and it had a section discussing the attributes of low noise signal cable: "Four elements combine to ensure adequate quality signal cable: A twisted signal pair with low resistance stranded copper conductors. Surrounded by a multiple-folded foil shield. With a copper stranded drain wire. All contained within an insulated outer jacket. In applications where such signal cable is used, a dramatic decrease in noise pickup will be experienced. The drain wire should be considered as the shield and should be connected as described previously. Signal cable meeting all four criteria for quality is Belden No. 8641." I haven't tried any of this cable(just using standard coax right now), but for those on the list who have built extra sensitive seismometers that require the lowest noise this Belden cable might help any noise problems. Greg Bajuk _____________________________________________________________________ Public Seismic Network Mailing List (PSN-L) From: Brett Nordgren Subject: Re: Low noise signal cable Date: Wed, 11 Nov 1998 12:04:18 -0500 Greg, Another benefit with using shielded twisted pair vs coax is that you can then configure the DI-150RS with differential inputs. I don't know if you're already doing that, but I'd expect differential to be a great improvement over single-ended operation. Brett At 08:21 AM 11/11/98 -0800, you wrote: >In applications where such signal cable is used, a dramatic decrease in >noise pickup will be experienced. The drain wire should be considered as >the shield and should be connected as described previously. Signal cable >meeting all four criteria for quality is Belden No. 8641." > >I haven't tried any of this cable(just using standard coax right now), but >for those on the list who have built extra sensitive seismometers that >require the lowest noise this Belden cable might help any noise problems. > >Greg Bajuk _____________________________________________________________________ Public Seismic Network Mailing List (PSN-L) From: Karl Cunningham Subject: Re: VBB loop response, etc Date: Wed, 11 Nov 1998 09:29:23 -0800 At 09:29 AM 11/11/98 -0500, Brett wrote: >Regarding the 200 hz hum you were seeing. I'll bet most anything that that >it's another mechanical resonance. My reasoning is as follows: Brett, Sean-Thomas -- Borrowing from feedback amplifier design techniques, a way to look for mechanical resonances is to interrupt the feedback and drive the voice coil with a function generator through a large resistor and look at the output of the displacement transducer with an oscilloscope to make a plot of amplitude and phase out to several hundred hertz. Feed a dc current to the voice coil also to zero the displacement transducer. When you plug this measured response into the equations instead of the theoretical second-order mass-spring function, one should be able to look for places where oscillations or ringing might occur. Karl Cunningham La Mesa, CA. PSN station #40 karlc@....... _____________________________________________________________________ Public Seismic Network Mailing List (PSN-L) From: Greg Subject: Speaking of piers Date: Wed, 11 Nov 1998 18:22:41 +0000 I'm getting closer to actually recording earthquakes. I have to depend on the computer for timing until I can afford GPS. WWV doesn't come in too good or something. Do I need a GOOD excuse? I got a GS-11D and Larry's amp is enroute. So I'm thinking about piers and digging and stuff. Which would be better for a geophone? Perched on a pier in a small housing or buried in a PVC pipe with some weights. I'm leaning towards the pier so I can get to the geophone if something goes wrong with the wiring or whatever. I figured it's better to ask before I pour 150 pounds of concrete. I don't think the garbage man would like that in the trash can. If anyone is using a 10 Hz geophone, when I plugged in the GS-11D the noise dropped through the floor. The noise goes up during the day and it goes down at night. Even during the day it's quieter than when I had the 10 Hz plugged in. The GS-11D 4.5 Hz vertical 380 Ohm was $60 US + shipping from GeoSpace. Is Larry on DSL now? I couldn't send this last night. I think he might have pinging denied on his computer, because traceroute found it, but all of the packets were lost when I pinged it. Then again maybe it's all my ISP's fault. ,Greg _____________________________________________________________________ Public Seismic Network Mailing List (PSN-L) From: Brett Nordgren Subject: Re: VBB loop response, etc Date: Wed, 11 Nov 1998 14:25:28 -0500 Karl, Yes, that sounds like just the ticket for smoking out the problem areas. For a quick qualitative look, in many cases you shouldn't even have to open up the loop. With everything operating normally, just connect a 1-10 meg resistor to the voice coil from an oscillator. Hook up a scope to a convenient point in the loop. Then set the signal level so there's no clipping in the loop and just tune around, say, from 2 to 1000 Hz. Resonances (and marginally stable loops) respond with very obvious peaks. There's another technique we used to use with a closed loop, using a passive clip-on AC milliameter probe connected to an oscillator output, as a voltage injection device. Need to look back at some old notes to remember exactly how it worked, but we could easily measure the closed loop gain and phase with the loop still operational. It worked particularly well within a decade or two of gain crossover, which is where you really need to know what's going on. Measuring with the loop active was necessary in our case, because we usually had so much gain that with the loop broken the output would slam to the limit, even if you tried to bias it just perfectly. Brett At 09:29 AM 11/11/98 -0800, you wrote: >Brett, Sean-Thomas -- > >Borrowing from feedback amplifier design techniques, a way to look for >mechanical resonances is to interrupt the feedback and drive the voice coil >with a function generator through a large resistor and look at the output >of the displacement transducer with an oscilloscope to make a plot of >amplitude and phase out to several hundred hertz. Feed a dc current to the >voice coil also to zero the displacement transducer. > >When you plug this measured response into the equations instead of the >theoretical second-order mass-spring function, one should be able to look >for places where oscillations or ringing might occur. > > >Karl Cunningham >La Mesa, CA. >PSN station #40 >karlc@....... _____________________________________________________________________ Public Seismic Network Mailing List (PSN-L) From: "Walt Williams" Subject: PSN-L: Speaking of piers Date: Wed, 11 Nov 1998 11:51:12 +0000 Hi Greg, >Greg If anyone is using a 10 Hz geophone, when I plugged in the GS-11D the noise dropped through the floor. The noise goes up during the day and it goes down at night. Even during the day it's quieter than when I had the 10 Hz plugged in. >Walt I have a 10 Hz geophone running. I have correlated the day noise as mostly caused by automobiles on the surface streets. At night traffic diminish and so does the noise. When it is quiet at night, (weekends 02:00am), there is little noise, then I will hear a truck coming down the street several blocks over, and I can 'see' it in the data. :) These sensors are tuned for specific bands. Walt Williams, 98.11.11 dfheli@.............. =================================== ------- Forwarded Message Follows ------- Date: Wed, 11 Nov 1998 18:22:41 +0000 From: Greg To: PSN Subject: Speaking of piers Reply-to: PSN-L Mailing List I'm getting closer to actually recording earthquakes. I have to depend on the computer for timing until I can afford GPS. WWV doesn't come in too good or something. Do I need a GOOD excuse? I got a GS-11D and Larry's amp is enroute. So I'm thinking about piers and digging and stuff. Which would be better for a geophone? Perched on a pier in a small housing or buried in a PVC pipe with some weights. I'm leaning towards the pier so I can get to the geophone if something goes wrong with the wiring or whatever. I figured it's better to ask before I pour 150 pounds of concrete. I don't think the garbage man would like that in the trash can. If anyone is using a 10 Hz geophone, when I plugged in the GS-11D the noise dropped through the floor. The noise goes up during the day and it goes down at night. Even during the day it's quieter than when I had the 10 Hz plugged in. The GS-11D 4.5 Hz vertical 380 Ohm was $60 US + shipping from GeoSpace. Is Larry on DSL now? I couldn't send this last night. I think he might have pinging denied on his computer, because traceroute found it, but all of the packets were lost when I pinged it. Then again maybe it's all my ISP's fault. ,Greg _____________________________________________________________________ Public Seismic Network Mailing List (PSN-L) _____________________________________________________________________ Public Seismic Network Mailing List (PSN-L) From: "Rex Klopfenstein, Jr." Subject: Re: VBB loop response-display problems Date: Wed, 11 Nov 1998 17:24:41 -0500 I must be doing something wrong, when I open this link my Acrobat Reader opens and then a blank screen comes up. I have opened other links that work fine with my Acrobat Reader. I have version 3 of Acrobat and 4.5 of Netscape. Any ideas? By the way, if I try to download the pdf file, I get an empty file message from Netscape. Brett Nordgren wrote: > > http://members.home.net/nordgren/public/loopmods.pdf -- Rex Klopfenstein, Jr. Bowling Green, OH rklopfen@......... www.wcnet.org/~rklopfen _____________________________________________________________________ Public Seismic Network Mailing List (PSN-L) From: meredith lamb Subject: Re: VBB loop response-display problems Date: Wed, 11 Nov 1998 16:14:49 -0700  

"Rex Klopfenstein, Jr." wrote:

I must be doing something wrong, when I open this link my Acrobat Reader opens
and then a blank screen comes up.  I have opened other links that work fine
with my Acrobat Reader.  I have version 3 of Acrobat and 4.5 of Netscape.  Any
ideas?  By the way, if I try to download the pdf file, I get an empty file
message from Netscape.

Brett Nordgren wrote:

>
> http://members.home.net/nordgren/public/

Rex,    knock off the loopnod stuff like above, and then click on it
in the text.  My computer setup has about the same components
programs as yours.  Then it comes up.

Meredith Lamb
 
  _____________________________________________________________________ Public Seismic Network Mailing List (PSN-L) From: Edward Cranswick Subject: Re: seismic base material Date: Wed, 11 Nov 1998 17:12:56 -0700 Karl & Sean-Thomas- "He was trying to isolate his apparatus from earth noise and thus supported the plate with inflated inner tubes. Presumably, setting such a plate in grout could do the opposite." A large mass of pier mounted on some more compliant material such as soil will act like an accelerometer. It will have a response that is flat to low-frequency groundmotions and rolls off above a corner frequency at f**-2 (12 dB/octave) like a 2-pole low-pass filter. Effectively, a seismograph mounted on such a pier will be shock-mounted and also subject to potentially large excitations from the underdamped resonance peak of the pier/substrate system. This is one way on both reducing local, high-frequency cultural noise and, if one is not careful, the high-frequency signals of local seismic events. Just a warning. -Edward Karl Cunningham wrote: > Ray -- > > Here is something I wrote on the subject a few weeks ago. > > Companies that cut granite slabs for surface plates (and other things) > sometimes have discards that they cannot use because of inclusions, cracks, > etc. I saw one used by an amateur laser experimenter that was about 3' by > 6' by 4" thick, weighed about 1000#, and it cost him about $100. The > surface wasn't mirror smooth, but as good as a concrete floor. He was > trying to isolate his apparatus from earth noise and thus supported the > plate with inflated inner tubes. Presumably, setting such a plate in grout > could do the opposite. > > Karl Cunningham > La Mesa, CA. > PSN station #40 > karlc@....... > > At 06:23 PM 11/10/98 -0500, you wrote: > >i remember reading an e-mail which indicated someone had a source for > >granite or stone base material. i cannot find the e-ma