From: Edward Cranswick Subject: Re: Reply (seismology and human consequences) Date: Tue, 30 Sep 1997 15:20:15 -0600 Stephen- I think that your recent correspondence (see excerpt below) about our seismological interest in earthquakes as opposed to their impact on human life has raised some very interesting and important issues that are useful to discuss. I know that when we (the USGS) chase large and damaging earthquakes, e.g., the 1988 Spitak Earthquake in Armenia, our focus on the technical aspects can keep us from being lost in the tragedy, i.e., the death of 1% of the population of Armenia. Alternatively, I remember spending the first few days after the 1994 Northridge Earthquake in California trying to whip our portable autonomous digital seismographs into shape. One afternoon we were on the UC Northridge campus, and if one looked around, one could see some building damage and the traffic lights near the campus that weren't functioning. But then abruptly at 4:00 PM, the lawn sprinklers turned on automatically all around us, but we still couldn't get the damn seismograph to work. In general, I agree with Barry Lotz, "that in the majority of cases that I can think of 'structures kill people not earthquakes'. I consider earthquakes part of the heartbeat of the planet. We have stethoscopes." We make the structures, and we should not forget our responsibility for that. Rather than think that "a good calibration may be bought at the expense of lives and homes", it is much better to think that those people and their dwellings did not die, were not destroyed, in vain, as is often the case. In many cases, the only record of ground motion we have is the damage done or not done to a structure. There were about 150,000 buildings inspected for damage after the Northridge Earthquake, about 20,000 were yellow- and red-tagged (designated as significantly or severely damaged), but the mainshock was locally recorded on scale by only about 200 strong motion accelerometers. So in most cases, in considering why the building on one side of the street collapsed, but the one on the other side did not, we don't know if the building collapsed because of strong ground shaking or because of structural flaws. In my early notion of the PSN, I visualized every house having a combination strong groundmotion accelerometer/ seismograph -- similar to all houses having smoke detectors -- and these cheap, standardized instruments would be calibrated. We need more reliable calibrations. Our old way of calibrating seismographs was with underground nuclear explosions. Prior to the late 1950's, before the US Air Force realized you could detect Soviet nuclear tests with seismographs, seismology was the domain of a handful of international scientists, but then it became Big Business (in terms of scientific funding). That was when calibration became a real important issue, and bombs were the best source of calibration. But if we can't respond to earthquakes which generate much of their energy in the frequency band to which the human nervous system is most sensitive, 1.0-20 Hz, how can we be aware of the really significant threats we face that have much longer time constants, such as global warming and environmental degradation? Barry says we have "stethoscopes" which allow us to hear the small, everyday seismic motions of the Earth above the extraordinary din of cultural noise we create, and this reminds us that She is alive and well. But as Bob Dylan said, "you don't need a weatherman to know which way the wind blows"; Los Angeles has a problem with too little water and gas and too many people; the problem with the place is as much the freeways as the earthquakes, and we are responsible for the former. Earthquakes are a voice that reminds us of our human position in the Cosmos. -Edward Stephen Paul wrote: .... > I am glad that you do think of the result as something other than a blip on > the screen. I live in LA, and when we have a major event here, well, it's > not real pretty. I look at a condemned building every day that was an > apartment bldg. before our last shaker, and I look at it out the window of > my office. There but for the Grace of God went we. And until those > stethoscopes can get people out in time, (which day must surely come, and > that is exactly why these lists have my full support), I do think it is > important to remember that a good calibration may be bought at the expense > of lives and homes. -- 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: Jim Hannon Subject: Re: Reply (seismology and human consequences) Date: Tue, 30 Sep 1997 17:27:17 -0500 Edward Cranswick wrote: > In my early notion of the PSN, I visualized every house having a > combination strong groundmotion accelerometer/ seismograph -- similar to > all houses having smoke detectors -- and these cheap, standardized > instruments would be calibrated. We need more reliable calibrations. There has been a lot of discussion of some sort of instrument to meet these needs. This comment reminds me of an instrument that I heard about years ago. While in school I had a summer job working for a small engineering firm in St. Louis. One of the things they did was to read data from a mechanical strain gage. This device was used to measure the traffic stress on bridges and I think in aircraft structures during flight tests. It was attached to a structural member of the bridge or aircraft and recorded stress as series of scratches on a small polished brass washer. The device was quite small and purely mechanical, it could remain in place for years and record the major flexures of the structural member it was attached to. It seems that such a device could supply at least part of the picture during a major quake. -- Jim Hannon http://soli.inav.net/~jmhannon/ 42,11.90N 91,39.26W WB0TXL _____________________________________________________________________ Public Seismic Network Mailing List (PSN-L) From: bzimmerman@............ Subject: Image maps Date: Tue, 30 Sep 1997 20:47:17 -0500 (EST) I seem to remember a post from someone offering to produce image maps of quake locations from a table of latitudes and longitudes. Are you still out there? Or does anyone remember the post? Can't seem to find it in the archives. What I'm looking for is the DOS program that does this. It would be nice to be able to easily update my own maps. Brian Zimmerman _____________________________________________________________________ Public Seismic Network Mailing List (PSN-L) From: wb6nvo@............. (Jim Skinner) Subject: Re: Decoding with sound card. Date: Tue, 30 Sep 1997 17:58:29 -0700 (MST) > >I was thinking about making an earthquake alarm using the remote SN. >I plan to use a frequency to voltage converter and set the alarm to >trigger when there is a pre-set voltage difference. Does anyone have any >thoughts on this? If distant enough, it may be used as a warning! > >Thanks, >Peter Fleming >alarm@........... > >_____________________________________________________________________ > >Public Seismic Network Mailing List (PSN-L) > >To leave this list email listserver@............. with the body of the >message: leave PSN-L > - Peter- I used one (actually several ) for "house alarms" for a number of years... they work great!!! One caution; don't pick one that goes through its autocal routines during the times you would prefer to be sleeping. A cheap and simple way to use one is to make/buy an audio filter and notch out the pilot tone. By varying the selectivity,etc you can actually dial an event of what ever size you want to hear...real easy to set up with an audio sig-gen. Jim Skinner _____________________________________________________________________ Public Seismic Network Mailing List (PSN-L) From: Edward Cranswick Subject: Re: 2.5 event @ Manassas, VA Date: Tue, 30 Sep 1997 21:40:38 -0600 Bob- Very nice record! (reminds me of home: I spent 4 years in graduate school studying East Coast earthquakes). -Edward RLLaney@....... wrote: > > The attached event file is for the subject quake on September 29, 1997. This > is my first submission of an event, so please let me know if additional > information is needed. > > Thank you. > > Bob Laney > > --------------------------------------------------------------- > > Name: 970929B.RL1 > Part 1.2 Type: unspecified type (application/octet-stream) > Encoding: base64 -- 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: More on SG sensor testing. Date: Tue, 30 Sep 1997 22:29:22 -0600 Larry- These are the poles and zeroes of the complex transfer function of the sensor (which I can't help much with) but that does not tell you what the site response transfer function is; or better yet, what the ratio of your site response to that of Berkeley's is. I am still cranking on the file conversion from SDAS (Ted Blank, i.e., PSN) format to DR100 Format with the info you gave me, and this may permit a comparison of site responses. -Edward Larry Cochrane wrote: > > At 09:10 AM 9/24/97 -0400, you wrote: > >Larry, > > I'm reading the e-mail which accumulated during a vacation in Los Alamos > >where my daughter is doing a post-doc in microbiology at the labs. (If you > >want to read some weird stuff, try her web page > >www-ls.lanl.gov/~sbarns/crenarchaeota.html The www-ls is correct but was > >something new to me.) Had a fine time-rode the narrow-gage train from > >Durango to Silverton (CO) again, a trip I can recommend. > > Your daughters research looks very interesting.... > > > I found your shake table work and the subsequent messages very > >interesting. The use of a stepping motor was a slick idea. A few comments > >about your comparison of the SG and Berkeley broadband seismograms:You > >compare them on the basis of peak-to-peak counts. I suggest that the > >comparison would be more meaningful if it was in terms of actual > >velocities, e. g., nanometers/sec. This is what I did in my write-up on > >the meter-movement calibrator for the Lehman. > > The biggest problem with my test was I didn't know how much the table was > moving. Since I was interested in freq. I didn't think it mattered, and, I > don't have the equipment to accurately measure the small movement. > > For the Berkeley seismometer I have the following response information: > > # > # ======== CHANNEL RESPONSE DATA ======== > B050F03 Station: BKS > B050F16 Network: BK > B052F04 Channel: BHN > B052F22 Start date: 1993,348,00:00 > B052F23 End date: No Ending Time > # ======================================= > # + +--------------------------------------------+ > + > # + | Response (Poles & Zeros), BKS ch BHN | > + > # + +--------------------------------------------+ > + > # > B053F03 Transfer function type: A [Laplace Transform > (Rad/sec)] > B053F04 Stage sequence number: 1 > B053F05 Response in units lookup: M/S - Velocity in Meters > Per Second > B053F06 Response out units lookup: V - Volts > B053F07 A0 normalization factor: 987.14 > B053F08 Normalization frequency: 0.02 > B053F09 Number of zeroes: 2 > B053F14 Number of poles: 4 > # Complex zeroes: > # i real imag real_error imag_error > B053F10-13 0 0.000000E+00 0.000000E+00 0.000000E+00 0.000000E+00 > B053F10-13 1 0.000000E+00 0.000000E+00 0.000000E+00 0.000000E+00 > # Complex poles: > # i real imag real_error imag_error > B053F15-18 0 -1.234120E-02 1.234150E-02 0.000000E+00 0.000000E+00 > B053F15-18 1 -1.234120E-02 -1.234150E-02 0.000000E+00 0.000000E+00 > B053F15-18 2 -1.958780E+01 2.456170E+01 0.000000E+00 0.000000E+00 > B053F15-18 3 -1.958780E+01 -2.456170E+01 0.000000E+00 0.000000E+00 > # > # + +-------------------------------------------+ > + > # + | Response (Coefficients), BKS ch BHN | > + > # + +-------------------------------------------+ > + > # > B054F03 Transfer function type: D > B054F04 Stage sequence number: 2 > B054F05 Response in units lookup: V - Volts > B054F06 Response out units lookup: COUNTS - Digital Counts > B054F07 Number of numerators: 51 > B054F10 Number of denominators: 0 > # Numerator coefficients: > # i, coefficient, error > B054F08-09 0 -3.777910E-08 -7.555820E-10 > B054F08-09 1 -4.148830E-07 -8.297660E-09 > B054F08-09 2 9.445450E-06 1.889090E-07 > B054F08-09 3 3.370620E-05 6.741250E-07 > B054F08-09 4 -2.429500E-05 -4.859010E-07 > B054F08-09 5 1.960520E-05 3.921050E-07 > B054F08-09 6 1.544480E-06 3.088960E-08 > B054F08-09 7 -2.150600E-05 -4.301210E-07 > B054F08-09 8 2.705530E-05 5.411070E-07 > B054F08-09 9 -1.676900E-05 -3.353810E-07 > B054F08-09 10 5.124170E-03 1.024830E-04 > B054F08-09 11 1.779800E-03 3.559600E-05 > B054F08-09 12 -4.332210E-03 -8.664430E-05 > B054F08-09 13 7.430310E-03 1.486060E-04 > B054F08-09 14 -1.039340E-02 -2.078670E-04 > B054F08-09 15 1.183280E-02 2.366560E-04 > B054F08-09 16 -1.055880E-02 -2.111760E-04 > B054F08-09 17 6.859030E-03 1.371810E-04 > B054F08-09 18 1.163370E-02 2.326740E-04 > B054F08-09 19 -2.604490E-02 -5.208970E-04 > B054F08-09 20 4.648550E-02 9.297090E-04 > B054F08-09 21 -7.015840E-02 -1.403170E-03 > B054F08-09 22 9.522160E-02 1.904430E-03 > B054F08-09 23 -1.275080E-01 -2.550170E-03 > B054F08-09 24 1.436970E-01 2.873940E-03 > B054F08-09 25 8.778300E-01 1.755660E-02 > B054F08-09 26 8.819290E-02 1.763860E-03 > B054F08-09 27 -1.059150E-01 -2.118300E-03 > B054F08-09 28 8.731180E-02 1.746240E-03 > B054F08-09 29 -6.899650E-02 -1.379930E-03 > B054F08-09 30 4.899210E-02 9.798410E-04 > B054F08-09 31 -3.020580E-02 -6.041160E-04 > B054F08-09 32 1.640370E-02 3.280730E-04 > B054F08-09 33 2.733980E-03 5.467960E-05 > B054F08-09 34 -7.899160E-03 -1.579830E-04 > B054F08-09 35 1.036420E-02 2.072840E-04 > B054F08-09 36 -9.902790E-03 -1.980560E-04 > B054F08-09 37 7.607170E-03 1.521430E-04 > B054F08-09 38 -4.881500E-03 -9.763010E-05 > B054F08-09 39 2.557260E-03 5.114520E-05 > B054F08-09 40 4.751230E-03 9.502450E-05 > B054F08-09 41 -8.744070E-05 -1.748810E-06 > B054F08-09 42 3.545030E-05 7.090060E-07 > B054F08-09 43 -3.244920E-05 -6.489850E-07 > B054F08-09 44 9.078710E-06 1.815740E-07 > B054F08-09 45 1.395880E-05 2.791750E-07 > B054F08-09 46 -2.044260E-05 -4.088520E-07 > B054F08-09 47 3.442010E-05 6.884020E-07 > B054F08-09 48 7.743230E-06 1.548650E-07 > B054F08-09 49 -3.925280E-07 -7.850560E-09 > B054F08-09 50 -2.914360E-08 -5.828710E-10 > # > # + +---------------------------------------+ > + > # + | Channel Sensitivity, BKS ch BHN | > + > # + +---------------------------------------+ > + > # > B058F03 Stage sequence number: 0 > B058F04 Sensitivity: 1.047200E+09 > B058F05 Frequency of sensitivity: 2.000000E-02 HZ > B058F06 Number of calibrations: 0 > # > > Unfortunately I have no idea on how to read this... If someone does, please > let me know. > > -Larry > > _____________________________________________________________________ > > 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: dean sevold Subject: Sound cards Date: Tue, 30 Sep 97 14:24:42 PDT All: Soundblaster has a large file for use with the SB boards; its the Sound = Blaster Dos Developers Kit,and includes drivers in most programming langu= ages. Soundblaster can be reached at http://www.creaf.com . _____________________________________________________________________ Public Seismic Network Mailing List (PSN-L) From: barry lotz Subject: Date: Tue, 30 Sep 1997 10:10:48 -0700 From: Norman Davis WB6SHI Subject: Re: Decoding with sound card. Date: Tue, 30 Sep 1997 19:57:05 >>I was thinking about making an earthquake alarm using the remote SN. >>I plan to use a frequency to voltage converter and set the alarm to >>trigger when there is a pre-set voltage difference. Does anyone have any >>thoughts on this? If distant enough, it may be used as a warning! I did too. I had a pll tuned to the pilot tone and when it changed freq I had it open a speaker so I could hear the tone. It worked great but drove the wife nuts cuz we had some RFI that would hit it some times and when the pilot tone droped the squelch would open and set the thing off. Norman Davis WB6SHI Email normd@............. Shingle Springs, Ca, USA it ain't local... _____________________________________________________________________ Public Seismic Network Mailing List (PSN-L) From: Robert L Barns <75612.2635@..............> Subject: Image maps Date: Thu, 2 Oct 1997 09:44:07 -0400 Brian Zimmerman, Yes, I did (and still do) offer to make a world map of your 'quakes if you supply a list of lats & lons. I use a rather involved process using a CAD (computer aided design) progr= am called DesignCAD. This is about $300. It included a BASIC-like programming language which = I use to read data files and plot points. If you have something like this,= I can supply the x-y pairs which draw the map and you can plot your own 'quakes. If you want to send me your 'quakes, make an ASCII file of lats & lons separated by a comma with one lat-lon pair per line. Include only lats &= lons, not magnitudes or other stuff. Bob Barns = _____________________________________________________________________ Public Seismic Network Mailing List (PSN-L) From: David A Nelson Subject: Re: Image maps Date: Fri, 03 Oct 1997 01:57:46 +1200 Bob, brian was looking for a way to plot the quakes on a relief map basically the same as I used for the PSN world map I supplied him with the map earlier in the week it would be great if there was a prog available that any map could be loaded into and then have the data plotted onto it Dave At 09:44 AM 10/2/97 -0400, you wrote: >Brian Zimmerman, > Yes, I did (and still do) offer to make a world map of your 'quakes if >you supply a list of lats & lons. >I use a rather involved process using a CAD (computer aided design) program >called DesignCAD. >This is about $300. It included a BASIC-like programming language which I >use to read data files and plot points. If you have something like this, I >can supply the x-y pairs which draw the map and you can plot your own >'quakes. > If you want to send me your 'quakes, make an ASCII file of lats & lons >separated by a comma with one lat-lon pair per line. Include only lats & >lons, not magnitudes or other stuff. >Bob Barns > > > > >_____________________________________________________________________ > >Public Seismic Network Mailing List (PSN-L) > >To leave this list email listserver@............. with the body of the >message: leave PSN-L > > Co-ordinator: New Zealand Public Seismic Network Dave A. Nelson 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: Don Rose Subject: Re: Image maps Date: Thu, 02 Oct 1997 09:03:37 -0700 Robert L Barns wrote: > > Brian Zimmerman, > Yes, I did (and still do) offer to make a world map of your 'quakes if > you supply a list of lats & lons. > I use a rather involved process using a CAD (computer aided design) program > called DesignCAD. > This is about $300. It included a BASIC-like programming language which I > use to read data files and plot points. If you have something like this, I > can supply the x-y pairs which draw the map and you can plot your own > 'quakes. > If you want to send me your 'quakes, make an ASCII file of lats & lons > separated by a comma with one lat-lon pair per line. Include only lats & > lons, not magnitudes or other stuff. > Bob Barns > > > > _____________________________________________________________________ > > Public Seismic Network Mailing List (PSN-L) > > To leave this list email listserver@............. with the body of the > message: leave PSN-L please delete me from the list. _____________________________________________________________________ Public Seismic Network Mailing List (PSN-L) From: GeE777@....... Subject: Re: Image maps Date: Thu, 2 Oct 1997 14:14:52 -0400 (EDT) Have you looked into -- DeLorme Mapping Lower Main Street, P.O.Box 298 Freeport, ME 04032 USA Telephone (207)865-1234 It comes on a CD Rom George << n a message dated 97-10-02 10:03:41 EDT, you write: Bob, brian was looking for a way to plot the quakes on a relief map basically the same as I used for the PSN world map I supplied him with the map earlier in the week it would be great if there was a prog available that any map could be loaded into and then have the data plotted onto it Dave >> _____________________________________________________________________ Public Seismic Network Mailing List (PSN-L) From: Edward Cranswick Subject: Trigger alogorithm Date: Thu, 02 Oct 1997 13:56:31 -0600 Barry- I couldn't follow the your frequency domain detection (trigger) algorithm in detail without having to think, which is a problem for me, but I am wondering why you triggering in realtime rather than recording continuously and then detecting by post processing and/or by correlation with a catalog of events from CalNet, NEIC, etc. -Edward barry lotz wrote: > > To All > I have been trying for a while to develope a "better" event triggering > routine for my system. The hope is to be able to detect teleseismic and > small local events in a noisy environment. I currently work in a trigger > environment rather than a continuous recording one. I'll try to describe > what I've been up to. > My detection routine is based on that described by Goforth & Herrin in > BSSA vol 71,no 4 , Aug 1981."An Automatic Seismic Signal Detection Algorithm > Based on the Walsh Transform". The basic description of the routine is as > follows. A window of data is acquired (in my system, 512 readings). A > transform is performed to convert this data to the frequency domain. G & H > used a Walsh transform for speed ,at a time when processors were slower. I > tried The Walsh routine and it definitely was faster but it produces aliases. > I use a 512 point FFT. The individual frequency magnitudes of the spectrum > are then summed. If one does not want to include a particular frequency it > can be avoided in the summing process. This weighted sum is stored as the > newest entry in a 512 point sequence of sums. The oldest sum is also > deleted at this time. The 512 entries are then sorted by size and the 75th % > sum is compared to the 50th % sum. A trigger threshold is obtained from the > following equation: Threshold = median + K*( 75% - median). K is a constant > which is in the range of 3-5. The current sum is then compared with this > continously varing threshold. If the current sum exceeds the threshold an > event is triggered. If the sum does not exceed the threshold it is saved and > another 512 points of data are acquired and the process is repeated.Actually > the window is 480 points of new data, I used an overlapping window of 32 > points. Because of transients, I wait to have 7-8 sums in sequence before I > trigger an event. I continue to save data, once the trigger is initiated, > until the FFT sum falls below the threshold. I then save the event to a > file. Because of lost P & S waves I keep two revolving 2k to 4k buffers > which are saved in front of the first trigger point( like Ted Blank's EMON). > I currently run the system at 8 hz just for teleseismic events. It has > helped me to detect events which I couldn't possibly have done before ,ie. > I can crank the gain up quite a bit. The only real problem I have had to > date has been with wind and trees. Wind gusts are transient noise in the > frequency range I am interested in. They don't trigger an event due to their > short duration but over time they raise the threshold so high that real > events can slip by. This winter will help the learning curve. I'll keep you > posted. I hope I haven't been to confusing. > > PS > > I have a FIR digital filter in the routine and have used it with limited > success. I can't get IIR filters to be stable over time. > > _____________________________________________________________________ > > 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: Jim Hannon Subject: Re: Decoding Date: Thu, 02 Oct 1997 17:15:44 -0500 Phil Giannini wrote: > > My > question is, does anybody know if there is a way to take a PSN file recorded > on SDR and turn it into a file that can be read by a sound card in the same > manner as the Landers quake was. > This question got me going. I have also wanted to listen to quakes. I did a little web browsing and found a shareware program Cool Edit 96 http://www.syntrillium.com/load.htm for those who use Win95 or NT this program will let you listen to files in PSN event file format. Since except for the header the data in the file is recorded as 16 bit PCM. Just ask Cool Edit to open "all files" and tell it 16 bit mono PCM and pick a sampling rate that sounds good. You will have to ignore or edit off the header data at the beginning of the file. You can then save the file in .au, .wav or your choice of audio formats. I converted one of Larry's files and put it on my web page at http://soli.inav.net/~jmhannon/seismology.html Click on Listen to an Earthquake. I started writing a File filter for Col Edit that would read PSN files and remove the header info but there is a small problem with the use of using the file extension to identify stations and Microsoft's use of extension to identify file types. Cool Edit only lets you put 4 different file extensions in a filter. So you would have to rename files to one of the extensions in the filter for it to work. -- Jim Hannon http://soli.inav.net/~jmhannon/ 42,11.90N 91,39.26W WB0TXL _____________________________________________________________________ Public Seismic Network Mailing List (PSN-L) From: Stephen Caruso Subject: Re: Image maps Date: Thu, 2 Oct 1997 20:29:23 -0400 (EDT) If you have windows 95 you can download software called imaging from microsoft imaging and edit faxes and images... so then download a map and edit it! STEPHEN CARUSO CET KB8UGH _____________________________________________________________________ Public Seismic Network Mailing List (PSN-L) From: barry lotz Subject: Re: Trigger alogorithm Date: Thu, 02 Oct 1997 09:20:47 -0700 Edward I guess because it's a challange. I thinks it also gives me a better understanding of how the event is composed. It also would be useful to me in a remote, "quiet" site with limited memory capacity. I don't know... maybe also because it's there. :-} Barry Edward Cranswick wrote: > > Barry- > I couldn't follow the your frequency domain detection (trigger) > algorithm in detail without having to think, which is a problem for me, > but I am wondering why you triggering in realtime rather than recording > continuously and then detecting by post processing and/or by correlation > with a catalog of events from CalNet, NEIC, etc. > -Edward > _____________________________________________________________________ Public Seismic Network Mailing List (PSN-L) From: Stephen Caruso Subject: Manassas quake? Area history? Date: Fri, 3 Oct 1997 21:44:09 -0400 (EDT) I was told there was an earthquake in VA recently. Did anybody see this one? It was 2.5. Does Va get many ever? STEPHEN CARUSO CET KB8UGH _____________________________________________________________________ Public Seismic Network Mailing List (PSN-L) From: Stephen Caruso Subject: Re: Manassas quake? Area history? Date: Fri, 3 Oct 1997 21:48:23 -0400 (EDT) 1:30 est 17:30 uct STEPHEN CARUSO CET KB8UGH _____________________________________________________________________ Public Seismic Network Mailing List (PSN-L) From: George Bush Subject: Wow, what was that Date: Sat, 04 Oct 1997 08:36:20 -0700 Did anyone else detect a large event at about 11:00 UT 10/4/97? My digitizing system is off-line, but the drum recorder pen went stop-to-stop. The event lasted about 15 minutes, so was not nearby, but also was probably not on the other side of the world. I really miss being able to use winquake to tell how far away the event was. George Bush Sea Ranch, CA 38.74, -123.5 _____________________________________________________________________ Public Seismic Network Mailing List (PSN-L) From: Marnie Gannon Subject: Re: Wow, what was that Date: Sat, 04 Oct 1997 09:52:00 -0700 George Bush wrote: > > Did anyone else detect a large event at about 11:00 UT 10/4/97? My > digitizing system is off-line, but the drum recorder pen went stop-to-stop. > The event lasted about 15 minutes, so was not nearby, but also was probably > not on the other side of the world. > > I really miss being able to use winquake to tell how far away the event was. > > George Bush > Sea Ranch, CA > 38.74, -123.5 > e0725c0-s- r n USGS-EARTHQUAKE-REPORT 10-04 0313 EARTHQUAKE REPORT == PRELIMINARY EARTHQUAKE REPORT == Rapid Earthquake Location Service U.S. Geological Survey, Menlo Park, California U.C. Berkeley Seismographic Stations, Berkeley, California Version 2: Updates lower and earlier versions of this earthquake report This event has been reviewed by David Oppenheimer-USGS A MODERATE EARTHQUAKE OCCURRED AT 03:57 AM PDT Saturday, Oct 04, 1997. THE MAGNITUDE 5.1 (ML) EVENT IS LOCATED 67 MILES W OF TRINIDAD, CA THE HYPOCENTRAL DEPTH IS 4.9 MILES. N.B. This earthquake occurs outside our network. The location is probably uncertain by 10 km and the depth is currently indeterminate. PRINCIPAL EARTHQUAKE PARAMETERS _______________________________ Magnitude : 5.12 ML Event Date & Time : 10/04/1997 03:57:33 AM PDT 10/04/1997 10:57:33 UTC Location : 41.0448 N, 125.4258 W : (41 deg. 2.69 min. N, 125 deg. 25.55 min. W) Depth : 7.9 km. deep ( 4.9 miles) Location Quality : Poor 108 km ( 67 miles) W (270 degrees) of Trinidad, CA 109 km ( 68 miles) WNW (285 degrees) of Eureka, CA 111 km ( 69 miles) WNW (298 degrees) of Ferndale, CA 112 km ( 69 miles) W (276 degrees) of McKinleyville, CA 115 km ( 71 miles) W (280 degrees) of Arcata, CA ADDITIONAL EARTHQUAKE PARAMETERS ________________________________ number of phases : 215 rms misfit : 0.39 seconds horizontal location error : 1.6 km vertical location error : 33.1 km maximum azimuthal gap : 236 degrees distance to nearest station : 112. km In region 2 (070) PACIFIC OCEAN event ID: 1020477 ====================================================================== ==== U.S. Geological Survey | Seismographic Station Seismology Section | 475 McCone Hall 345 Middlefield Road - MS 977 | U.C. Berkeley Menlo Park, CA 94025 | Berkeley, CA 94720- 4760 Voice : 415-329-4085 | 510-642-3977 Earthquake Info : 415-329-4025 | 510-642-2160 Fax : 415-329-5163 | 510-643-5811 E-mail : ncsn@................... | bdsn@................ edu More Information about this event and other earthquakes is available on the Worldwide Web at http://quake.wr.usgs.gov EDIS-10-04-97 0426 PDT _____________________________________________________________________ Public Seismic Network Mailing List (PSN-L) From: lahr@................. (Dr. John Lahr (USGS-GI Seismologist)) Subject: Re: Image maps Date: Sat, 4 Oct 1997 11:33:48 -0800 There is a program available on the web called Seismic that can plot earthquake epicenters on a map, in cross section, or in 3-D view. It actually plots them one at a time in speeded up time so that you see the pattern of seismicity as it develops over time. The program comes with a global data set and shaded relief background maps for the entire world and for many sub-regions of the world. It also includes a program that can convert from various formats into the ".hy3" format used for its earthquake data sets. There are far too many features to describe in detail here. For more information on Seismic, check out Alan Jones' home page at: http://sunquakes.geol.binghamton.edu/faculty/jones/ The current version of the program is called Seismic/Eruption, as it also displays volcanic eruptions as they occur. This program, and another called Seismic/Waves are included in a new exhibit at the Smithsonian in Washington. Seismic/Waves is a neat program that shows seismic wave fronts as they move outward from an earthquake's hypocenter. These are shown graphically on a cross section of the earth, so one can see how the structure of the earth produces reflection, refractions, and shadow zones. On the top of the screen, one sees an actual seismic record with the phases identified. The programs are free, but a $30 registration fee is requested if you enjoy using them. For teachers and students in K-12, registration is not requested. JCLahr ################################## John C. Lahr ################################# Seismologist ################################ U.S. Geological Survey ############################### c/o Geophysical Institute ############################## 903 Koyukuk Drive ~~~~~~~~~~~~~~ Get ~~~~~~~~~~ ############################# ########################################################### P.O. Box 757320 ################################ Fairbanks, AK 99775 ################################# Phone: (907) 474-7997 ################################## Fax: (907) 474-5618 ~~~~~~~~ the thrust? ~~~~~~~~~~~~~~ lahr@........ #################################### http://www.aeic.alaska.edu/Input/lahr/ _____________________________________________________________________ Public Seismic Network Mailing List (PSN-L) From: barry lotz Subject: new event Date: Sat, 04 Oct 1997 06:53:13 -0700 All Looks like something coming thru @ 01:37 UTC 10/05. Barry _____________________________________________________________________ Public Seismic Network Mailing List (PSN-L) From: David A Nelson Subject: Re: new event Date: Sun, 05 Oct 1997 14:22:32 +1200 how's it look barry, was it an aftershk to the offshore cal. 5.1 ?? Dave At 06:53 AM 10/4/97 -0700, you wrote: >All > Looks like something coming thru @ 01:37 UTC 10/05. > Barry > >_____________________________________________________________________ > >Public Seismic Network Mailing List (PSN-L) > >To leave this list email listserver@............. with the body of the >message: leave PSN-L > > 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: barry lotz Subject: Re: new event Date: Sat, 04 Oct 1997 07:57:39 -0700 David Weird. Maybe it's my washing machine. :-]. I'll upload it. Barry David A Nelson wrote: > > how's it look barry, was it an aftershk to the offshore cal. 5.1 ?? > > Dave > _____________________________________________________________________ Public Seismic Network Mailing List (PSN-L) From: David A Nelson Subject: Re: new event Date: Sun, 05 Oct 1997 15:07:32 +1200 well barry, never seen anything like that before the mind boggles !!! Dave At 07:57 AM 10/4/97 -0700, you wrote: >David > Weird. Maybe it's my washing machine. :-]. I'll upload it. > Barry > >David A Nelson wrote: >> >> how's it look barry, was it an aftershk to the offshore cal. 5.1 ?? >> >> 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: "Dott. Roberto E. Pozzo" Subject: PSN Italy works ! Date: Sun, 05 Oct 1997 13:03:57 +0200 Dear Larry C.,Edward C. and all PSN guys . PSN ITALY is now a reality ! Few days ago, as you know, in Central Italy two earthquakes (5.5 and 5.9 followed by more than 90 aftershocks) have caused 6 victims, about 120 injuried and more of 5000 homeless).The famous S. Francesco Church in Assisi also has suffered very serious damages ( a part of a Cimabue's masterpiece is forever lost ) . Francesco,Giovanni and I are keeping in touch H24 by phone and we exchange our wq recordings daily for study proposals. This in the spirit of P.S.N. and the first really well-working collaboration between amateurs in seismology in Italy during a seismic period. Count on us ! roberto _____________________________________________________________________ Public Seismic Network Mailing List (PSN-L) From: mark widerstrom Subject: Re: Cost for seismograph Date: Sun, 05 Oct 1997 07:04:30 -0500 Anyone have the costs involved with doing a seismograph? I see alot of portable units but something not pocket eating would be appreciated. I am a ham radio operator and im looking at frequencies above 16 mhz that could be reading seismo triggers. Thanks for your time Markww in Houston Texas N5UOA Support your local disabled veterans units. Anyone have the costs involved with doing a seismograph?  I see alot of portable units but something not pocket eating would be appreciated.  I am a ham radio operator and im looking at frequencies above 16 mhz that could be reading seismo triggers.  Thanks for your time

Markww  in Houston Texas
N5UOA

Support your local disabled veterans units. From: Larry Cochrane Subject: Re: Manassas quake? Area history? Date: Sun, 05 Oct 1997 11:34:21 -0700 At 09:44 PM 10/3/97 -0400, Stephen Caruso wrote: I don't know about the history part, but, Bob Laney who lives in Herndon VA, about 15 to 25 miles from the event, received this event and it was his first one! He just got his system up and running when he capture the event. He sent in a very nice seismogram that can be download using the following URL: ftp:://psn.quake/net/quakes/9709/970929a.rl1. Bob Laney, can you send Dave Nelson your station info so he can add it to the PSN Map? Thanks, and good job getting your station up and running! -Larry Cochrane Redwood City, PSN >I was told there was an earthquake in VA recently. Did anybody see this >one? It was 2.5. Does Va get many ever? > >STEPHEN CARUSO CET >KB8UGH > > > >_____________________________________________________________________ > >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 Italy works ! Date: Sun, 05 Oct 1997 11:50:08 -0700 Hi Guys, Great! Can you also send your event files to event@............. for archiving? This way we call can see them... I would also like to remind people that I have the new NewFile mailing list that will send you a email message when people send in event files to the event@... address above. This email message will not have the attached file like the NewEvent mailing list. You can use the web page at http://psn.quake.net/maillist.html to subscribe/unsubscribe to all of the lists I have. -Larry Cochrane Redwood City, PSN At 01:03 PM 10/5/97 +0200, you wrote: >Dear Larry C.,Edward C. and all PSN guys . > >PSN ITALY is now a reality ! Few days ago, as you know, in Central Italy >two earthquakes (5.5 and 5.9 followed by more than 90 aftershocks) have >caused 6 victims, about 120 injuried and more of 5000 homeless).The >famous S. Francesco Church in Assisi also has suffered very serious >damages ( a part of a Cimabue's masterpiece is forever lost ) . > >Francesco,Giovanni and I are keeping in touch H24 by phone and we >exchange our wq recordings daily for study proposals. > >This in the spirit of P.S.N. and the first really well-working >collaboration between amateurs in seismology in Italy during a seismic >period. > >Count on us ! > roberto > > >_____________________________________________________________________ > >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: Cost for seismograph Date: Sun, 05 Oct 1997 12:18:29 -0700 At 07:04 AM 10/5/97 -0500, Mark wrote: > Anyone have the costs involved with doing a seismograph? That's a hard one... depends on what type of sensor you want to make (Lehman, SG, or something else), parts and equipment you have on hand, etc etc etc. Besides the sensor you will need some type of recording device. This could be a chart recorder (arrgggg) or a computer system with an Analog to Digital convert card and software. The homebuilt FAQ at http://psn.quake.net/info/homefaq.txt has more info about the hardware/software need to get a station up and running. >>> I see alot of portable units but something not pocket eating would be appreciated. I am a ham radio operator and im looking at frequencies above 16 mhz that could be reading seismo triggers. Thanks for your time Markww in Houston Texas <<<<<<<< Not sure what portable units you are talking about? As far as "looking for seismic triggers above 16 mhz", you on your own on that one... If you make a seismometer, you will be picking up seismic waves in the 30 second to 20hz range. Hope this helps. -Larry Cochrane Redwood City, PSN _____________________________________________________________________ Public Seismic Network Mailing List (PSN-L) From: David A Nelson Subject: Re: Cost for seismograph Date: Mon, 06 Oct 1997 10:57:22 +1200 Larry, at least when my HDD died 3 days ago the good ol' pen recorder still chugged relentlessly on Dave Larry wrote: This could be a chart recorder (arrgggg) or a computer system with an Analog to Digital convert card and software. 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: PSN Italy works ! Date: Sun, 05 Oct 1997 23:10:10 -0600 Roberto- I am sorry to hear about the deaths, injuries and damage caused by the earthquake. I am glad to hear that your PSN connection has helped you, Giovanni, and Francesco to experience what has happened together ... and so you are closer to each other and to the earth of Italy. -Edward Dott. Roberto E. Pozzo wrote: > > Dear Larry C.,Edward C. and all PSN guys . > > PSN ITALY is now a reality ! Few days ago, as you know, in Central Italy > two earthquakes (5.5 and 5.9 followed by more than 90 aftershocks) have > caused 6 victims, about 120 injuried and more of 5000 homeless).The > famous S. Francesco Church in Assisi also has suffered very serious > damages ( a part of a Cimabue's masterpiece is forever lost ) . > > Francesco,Giovanni and I are keeping in touch H24 by phone and we > exchange our wq recordings daily for study proposals. > > This in the spirit of P.S.N. and the first really well-working > collaboration between amateurs in seismology in Italy during a seismic > period. > > Count on us ! > roberto > > _____________________________________________________________________ > > 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: [Fwd: Manassas quake] Date: Sun, 05 Oct 1997 23:14:29 -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". From: Kees Verbeek Subject: Quake!!! Date: Tue, 7 Oct 1997 02:31:56 +0200 (MET DST) Hi all, Just had a quake , start , about 23.30 i'm afraid its Itali again?!!! Greetings , Kees Verbeek Holland. _____________________________________________________________________ Public Seismic Network Mailing List (PSN-L) From: "Francesco" Subject: R: Quake!!! Date: Tue, 7 Oct 1997 02:40:42 +0100 Hello Kees, yes. Another medium quake, perhaps 5.5 Ms Have you registered the event? Please, get me file as soon as possible. I leave 40 km far the epicentre. Thank you Francesco Nucera ---------- > Da: Kees Verbeek > A: PSN-L Mailing List > Oggetto: Quake!!! > Data: marted=EC 7 ottobre 1997 1.31 > = > Hi all, > = > = > = > Just had a quake , start , about 23.30 i'm afraid its Itali again?!!! > = > Greetings , > = > = > Kees Verbeek > Holland. > = > = > _____________________________________________________________________ > = > 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: "Dott. Roberto E. Pozzo" Subject: Re: Quake!!! Date: Tue, 07 Oct 1997 02:45:04 +0200 Kees Verbeek wrote: > > Hi all, > > Just had a quake , start , about 23.30 i'm afraid its Itali again?!!! > > Greetings , > > Kees Verbeek > Holland. > > _____________________________________________________________________ > > Public Seismic Network Mailing List (PSN-L) > > To leave this list email listserver@............. with the body of the > message: leave PSN-L Yes, Kes it's a Central Italy quake . Again ! provisional calculations reports M +- 5.5 . Epicentral zone: near Assisi . Mercalli VII/VIII. No new victims reported (by now ) roberto _____________________________________________________________________ Public Seismic Network Mailing List (PSN-L) From: Kees Verbeek Subject: Re: R: Quake!!! Date: Tue, 7 Oct 1997 03:41:49 +0200 (MET DST) At 02:40 7-10-97 +0100, you wrote: >Hello Kees, >yes. Another medium quake, perhaps 5.5 Ms >Have you registered the event? > >Please, get me file as soon as possible. > >I leave 40 km far the epicentre. > >Thank you > >Francesco Nucera > >---------- Hello Francesco, 40 km. !!!!!!!! I hope everything is alright over there. Sorry I can't give any computer-file about the quake because i'm a kind of old-fashion seismo-fanatic . I only record on a home-brewed drum recorder,that's behind me now , so I immediately can see when something goes wrong. Perhaps France can? again sorry for no help, greetings, Kees Verbeek Holland _____________________________________________________________________ Public Seismic Network Mailing List (PSN-L) From: Larry Cochrane Subject: Needs for informations about a vertical sensor sismograph Date: Mon, 06 Oct 1997 18:02:01 -0700 Hi, I received this yesterday. Can anyone help them? They are not on the PSN-L list so please send email directly to them and CC the list. Thanks, -Larry Cochrane Redwood City, PSN >X-Authentication-Warning: www.utbm.fr: news set sender to using -f >Date: Sat, 05 Oct 1996 14:56:18 +0100 >From: Yohann LEDIEU >X-Mailer: Mozilla 3.01 (WinNT; I) >To: cochrane@.............. >CC: nicolas-rivron@....... >Subject: Needs for informations about a vertical sensor sismograph >X-MIME-Autoconverted: from 8bit to quoted-printable by www.utbm.fr id OAA02937 > >Dear sir >We are two french students from the Institut polytechnique de Sevenans >(IPSé). >As a project, this year, we have to build a vertical sensor sismograph >so that we need some more informations about it. >We already read your web site but we didn't found anything about >vertical sensor. >Could you please help us by sending us informations, plans or web >addresses. > yours faithfully, > > Rivron Nicolas > _____________________________________________________________________ Public Seismic Network Mailing List (PSN-L) From: Edward Cranswick Subject: [Fwd: USGS Menlo Park move] Date: Mon, 06 Oct 1997 23:26:12 -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". From: Edward Cranswick Subject: Re: USGS Menlo Park move Date: Mon, 06 Oct 1997 23:37:46 -0600 Ted Blank- But the reality of the situation is that you now, and the original PSN members then, and the USGS Menlo Park all live where the earthquakes are .... but I just live in Colorado and talk about it. So ultimately it's up to all you Bay Area people to be aware of and prepare yourself for the earthquakes that are part of what makes the Bay Area such a beautiful place to live. However, thank you for letting me know what's happening. -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: shammon1@............. Subject: Re: Needs for informations about a vertical sensor sismograph Date: Mon, 06 Oct 1997 23:40:25 -0700 Larry Cochrane wrote: >=20 > Hi, >=20 > I received this yesterday. Can anyone help them? They are not on the PS= N-L > list so please send email directly to them and CC the list. >=20 > Thanks, >=20 > -Larry Cochrane > Redwood City, PSN >=20 > >X-Authentication-Warning: www.utbm.fr: news set sender to > using -f > >Date: Sat, 05 Oct 1996 14:56:18 +0100 > >From: Yohann LEDIEU > >X-Mailer: Mozilla 3.01 (WinNT; I) > >To: cochrane@.............. > >CC: nicolas-rivron@............. I sent them the Vertical.GIF and AMP_= 2.GIF files file from the San Jose BBS. Regards, Steve Hammond PSN - San Jose, California=20 > >Subject: Needs for informations about a vertical sensor sismograph > >X-MIME-Autoconverted: from 8bit to quoted-printable by www.utbm.fr id > OAA02937 > > > >Dear sir > >We are two french students from the Institut polytechnique de Sevenans > >(IPS=E9). > >As a project, this year, we have to build a vertical sensor sismograph > >so that we need some more informations about it. > >We already read your web site but we didn't found anything about > >vertical sensor. > >Could you please help us by sending us informations, plans or web > >addresses. > > yours faithfully, > > > > > > >=20 > _____________________________________________________________________ >=20 > Public Seismic Network Mailing List (PSN-L) >=20 > To leave this list email listserver@............. with the body of the > message: leave PSN-L _____________________________________________________________________ Public Seismic Network Mailing List (PSN-L) From: shammon1@............. Subject: Re: Needs for informations about a vertical sensor sismograph Date: Mon, 06 Oct 1997 23:57:11 -0700 Larry, I sent the two students the Vertical.GIF file and AMP_2.GIF file from the PSN San Jose BBS.=20 Regards, Steve Hammond PSN San Jose, California Larry Cochrane wrote: >=20 > Hi, >=20 > I received this yesterday. Can anyone help them? They are not on the PS= N-L > list so please send email directly to them and CC the list. >=20 > Thanks, >=20 > -Larry Cochrane > Redwood City, PSN >=20 > >X-Authentication-Warning: www.utbm.fr: news set sender to > using -f > >Date: Sat, 05 Oct 1996 14:56:18 +0100 > >From: Yohann LEDIEU > >X-Mailer: Mozilla 3.01 (WinNT; I) > >To: cochrane@.............. > >CC: nicolas-rivron@....... > >Subject: Needs for informations about a vertical sensor sismograph > >X-MIME-Autoconverted: from 8bit to quoted-printable by www.utbm.fr id > OAA02937 > > > >Dear sir > >We are two french students from the Institut polytechnique de Sevenans > >(IPS=E9). > >As a project, this year, we have to build a vertical sensor sismograph > >so that we need some more informations about it. > >We already read your web site but we didn't found anything about > >vertical sensor. > >Could you please help us by sending us informations, plans or web > >addresses. > > yours faithfully, > > > > > > >=20 > _____________________________________________________________________ >=20 > Public Seismic Network Mailing List (PSN-L) >=20 > 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: lighter side of software Date: Wed, 08 Oct 1997 12:58:55 +1200 hi all, here's a little gem I discovered that I hope will bring a smile to the faces of the masses DEFINITION OF WINDOWS 95: 32-bit extensions and a graphical shell for a 16-bit patch to an 8-bit operating system originally coded for a 4-bit microprocessor, written by a 2-bit company that can't stand 1-bit of competition. 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: Larry Cochrane Subject: Re: lighter side of software Date: Wed, 08 Oct 1997 11:41:09 -0700 Very good... and unfortunately true! -Larry At 12:58 PM 10/8/97 +1200, you wrote: >hi all, > here's a little gem I discovered that I hope will bring a smile to >the faces of the masses > > DEFINITION OF WINDOWS 95: > > 32-bit extensions and a graphical shell for a > 16-bit patch to an > 8-bit operating system originally coded for a > 4-bit microprocessor, written by a > 2-bit company that can't stand > 1-bit of competition. > > >Dave _____________________________________________________________________ Public Seismic Network Mailing List (PSN-L) From: Edward Cranswick Subject: Re: lighter side of software Date: Wed, 08 Oct 1997 14:19:49 -0600 Dave & Larry- But that proves the system and the people who use it are very adaptable unlike some other systems which required an investment of a 100k just to logon on -- and that is the sign of a organism/system that survives by evolving. -Edward Larry Cochrane wrote: > > Very good... and unfortunately true! > -Larry > > At 12:58 PM 10/8/97 +1200, you wrote: > >hi all, > > here's a little gem I discovered that I hope will bring a smile to > >the faces of the masses > > > > DEFINITION OF WINDOWS 95: > > > > 32-bit extensions and a graphical shell for a > > 16-bit patch to an > > 8-bit operating system originally coded for a > > 4-bit microprocessor, written by a > > 2-bit company that can't stand > > 1-bit of competition. > > > > > >Dave > > _____________________________________________________________________ > > 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: Robert L Barns <75612.2635@..............> Subject: compare. of 3 sensors for Kermadec Date: Wed, 8 Oct 1997 20:28:12 -0400 Larry, I downloaded 970920A.BKN, .LC1 & .LC3. of the Kermadec 6.9 event. = Thanks for taking the trouble of making files so that it is easy to compa= re them. The comparison is very informative. (My great bad luck was to have= my rig down for this event--we had a power dip while I was out of town an= d I had not provided for auto restart of SDR in AUTOEXEC.BAT.) sensor p-p surf p-p bg = S N = S/N .BKN Berk. broadband 5340 200 27 .LC1 Lehman 3440 170 20 .LC3 S-G new integ. 9740 800 12 Since the p-p bg is an eyeball est., I'm not sure that the difference between 27 and 20 is significant. Since the S/N ratio would be dependent= on the high freq. cutoff, I looked at the FFT for all three and it looks like they are all the same. The visual appearance of all three 'grams is remarkably similar. Lay = & Wallace ("Modern Global Seismology") p 188 show that the broadband sensor= s have response from ~ 9 Hz to less than .001 Hz. I was amazed that the FFT's for the three sensors were remarkably similar and esp. that they showed about the same fraction of energy at low freqs., say below .02 Hz.= Since I have only a Lehman, I was delighted to see that yours was only slightly inferior to the broadband rig. I suppose that the Berk. sensor = is in a good location (borehole?) so the similarity of the S/N must make you= feel good about your location. I have some questions:1. Since the S wave is very strong, how come the = SS and SSS seem to be absent? 2. The LQ calculates to be at about 16:56:12= =2E = What is the nice 'blob' (do you have a better term for this?) centered a= t about 16:51:48? This 'blob' has a period of about 23" and the sections around the LQ and LR are about 16". I would greatly appreciate your repeating this exercise the next time w= e have a teleseismic boomer--one which I should also get. A suggestion for a new feature for WINQUAKE--how about a facility for getting an RMS avg. value for a zoomed region? This would be a better meas. of the background amplitude. Maybe you can think of something bett= er than RMS. Bob Barns = = = = _____________________________________________________________________ Public Seismic Network Mailing List (PSN-L) From: "Kasey Benson" Subject: Re: Wow, what was that Date: Wed, 8 Oct 1997 20:03:14 -0700 ---------- > How does one get off this list. _____________________________________________________________________ Public Seismic Network Mailing List (PSN-L) From: frankcnd@.......... (Frank Condon) Subject: Date: Thu, 9 Oct 1997 02:24:49 -0700 (PDT) Subject: Parkfield Prediction X-Mailer: Hi all! I remember reading about the possibility of an 8.0 occurring on the San Andreas fault immediately following a 6.0 or greater in the Parkfield area. Can anyone enlighten me about this theory? Also, seeing very erratic low frequency 0-3 Hz geo-magnetic field disturbances in the Cucamonga/San Bernardino County area on my equipment. Can anyone else correlate with me on this? I think it might be something else going on on the San Jacinto fault that is causing it. reply to: frankcnd@.......... _____________________________________________________________________ Public Seismic Network Mailing List (PSN-L) From: Stephen Paul Subject: Re: lighter side of software Date: Thu, 09 Oct 1997 02:36:20 -0700 David A Nelson wrote: > hi all, > here's a little gem I discovered that I hope will bring a smile to > the faces of the masses > > DEFINITION OF WINDOWS 95: > > 32-bit extensions and a graphical shell for a > 16-bit patch to an > 8-bit operating system originally coded for a > 4-bit microprocessor, written by a > 2-bit company that can't stand > 1-bit of competition. > > 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 > > ____________________________________________________________________ That one kept me laughing for hours, Dave! Thanks for passing it along. -- Stephen :^) _____________________________________________________________________ Public Seismic Network Mailing List (PSN-L) From: GeoMonitr@....... Subject: Re: HAM interested in earthquake prediction Date: Thu, 9 Oct 1997 12:25:12 -0400 (EDT) Many people have been trying to duplicate the experiments of Anthony Fraser-Smith at Stanford, by detecting ULF signals that may be a link between earthquake precursors and human reactions. I started a newsletter on the subject, GeoMonitor, and I have all 6 years of back issues, including some amateur circuits for ULF detection. The newsletter is now being published by Charles Patton, 21490 Camino Arriba, Murrieta, CA 92562; (909) 698-9657. Good luck VInce _____________________________________________________________________ Public Seismic Network Mailing List (PSN-L) From: GeoMonitr@....... Subject: Re: HAM interested in earthquake prediction Date: Thu, 9 Oct 1997 12:28:09 -0400 (EDT) Yeah, as if quake predictors are right up there with Astrologers! Geez, when are you so-called scientists going to get an OPEN MIND!!?? Is it so inconceivable that precursors would have an electromagnetic component that a human or animal is capable of picking up? _____________________________________________________________________ Public Seismic Network Mailing List (PSN-L) From: GeE777@....... Subject: Re: HAM interested in earthquake prediction Date: Thu, 9 Oct 1997 14:17:51 -0400 (EDT) Hi Why don't we check it out. Have dog pounds keep track of how many dogs are lost and/or picked up each day. See if this number increases prior to an earthquake. That certainly can't be a very expensive experiment. n a message dated 97-10-09 12:31:02 EDT, GeoMonitr@....... writes: << Is it so inconceivable that precursors would have an electromagnetic component that a human or animal is capable of picking up? >> _____________________________________________________________________ Public Seismic Network Mailing List (PSN-L) From: "Rev. Bob Shannon" Subject: Re: HAM interested in earthquake prediction Date: Thu, 9 Oct 1997 13:51:29 -0700 (PDT) On Thu, 9 Oct 1997 GeoMonitr@....... wrote: > Is it so inconceivable that precursors would have an > electromagnetic component that a human or animal > is capable of picking up? When I was in my single digits back in the early 1950's I truly enjoyed building electronic projects...I felt that I could design some myself and it was the phase of life that led me to working in electronics for many years. Building and monitoring earthquake devices sounds like fun...and refining the instruments sounds like a bit of fun but maybe a bit more like drudgery.....On the other hand...attempting to figure out what sort of possible precursors could be causing 'signals' which humans could possibly be capable of receiving is even more exciting.... Let me example. I feel that ELF has a finger in this somewhere and so does Ben Parks of Placerville Ca. Ben has been following F-Smiths work and is a friend of his. Ben designed some pretty hefty A-D hard and software to monitor ULF and ELF. I have a ref. to him on my homepage.... I am wondering a bit with Vince, if it is at least in the same ballpark to monitor precursors as well as the actual quake...or at least make an attempt to discover the thread which ties them? Bob http://iea.com/~rshannon Rev. Robert Shannon Sr. Hon. DD Theology Pinpoint Newsletter "The web existed before spiders. The web existed before the net... We are all a part of the web and whatever we do to part - we do to the whole" ------------------------------------------------------------------ _____________________________________________________________________ Public Seismic Network Mailing List (PSN-L) From: Stephen Caruso Subject: Re: HAM interested in earthquake prediction Date: Thu, 9 Oct 1997 20:42:10 -0400 (EDT) I remember being in NW Wash. state in the mid 70's. I was on the road and settled down for the night. I remember hearing the animals around the area sounding distressed and then, boom, there was a tremor. The next night Iwas in someones house on the third floor and there was another yet stronger. On Thu, 9 Oct 1997 GeE777@....... wrote: > Hi > Why don't we check it out. Have dog pounds keep track of how many dogs are > lost and/or picked up each day. See if this number increases prior to an > earthquake. That certainly can't be a very expensive experiment. > > > > > n a message dated 97-10-09 12:31:02 EDT, GeoMonitr@....... writes: > > << > Is it so inconceivable that precursors would have an > electromagnetic component that a human or animal > is capable of picking up? > > >> > > > _____________________________________________________________________ > > Public Seismic Network Mailing List (PSN-L) > > To leave this list email listserver@............. with the body of the > message: leave PSN-L STEPHEN CARUSO CET KB8UGH _____________________________________________________________________ Public Seismic Network Mailing List (PSN-L) From: Jim Hannon Subject: Re: HAM interested in earthquake prediction Date: Thu, 09 Oct 1997 20:24:08 -0500 Stephen Caruso wrote: > > I remember being in NW Wash. state in the mid 70's. I was on the road and > settled down for the night. I remember hearing the animals around the area > sounding distressed and then, boom, there was a tremor. The next night > Iwas in someones house on the third floor and there was another yet stronger. > > Hear is my story. :) I was in Iran in the 1960's when one of the big quakes struck. I distinctly remember the day before the quake I had a conversation with my dad about what to do if a quake happened. Chance or some sense -- I have no idea. Jim Hannon http://soli.inav.net/~jmhannon/ 42,11.90N 91,39.26W WB0TXL _____________________________________________________________________ Public Seismic Network Mailing List (PSN-L) From: David A Nelson Subject: Mt Ruapehu "burps" Date: Fri, 10 Oct 1997 17:33:36 +1200 Hi all, Seismic activity has again started to rise below the crater lake of Mt Ruapehu (central Nth Is., New Zealand) after a 15 months of calm since the last large eruptions. Almost continuous harmonic tremor as well as individual events are 3 times up on the normal level of activity. And early am on the 10 Oct 97 NZST (late pm UTC 9 Oct.) the first small steam cloud was seen above the mountain. The Alert has been raised to level 2 on the international scale of 1 to 5, 5 being full maj. eruption 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: TMichel917@....... Subject: Streckeisen Date: Fri, 10 Oct 1997 15:08:38 -0400 (EDT) Hi Jean-Yves! Some time ago I read your mail concerning the Streckeisen seismometers. The Streckeisen STS-1 force-balance-seismometer is in its current version a "very-broad-band"-seismometer with a response flat to velocity from 0.1 to 360 sec period. It is only for observatory use. The mechanical design of the vertical sensor (STS-1V/VBB) is based on a semicircularly bent leaf spring which produces a very small and linear restoring force. The horizontal sensors (STS-1H/VBB) use pendulums of the "garden-gate"-type. The mechanics are shielded against variations in temperature, air pressure and magnetic field (only STS-1V/VBB). The external electronics use a combination of differential, proportional and integral feedback. The boom position is sensed by a LVDT (linear variable differential transformer) and the feedback force is generated by moving-coil transducers. The mechanics of the STS-2, which is also a force-balance-seismometer, are different from that of the STS-1 while the electronics are very similar. The STS-2 consists of three identical obliquely-oriented sensors in a single, sealed package. It is optimized for quick and simple installation. As boom position sensor the STS-2 uses a capacitive displacement sensor, the feedback force is generated by a moving coil transducer. Technical Data STS-1 Mechanical free period: Virtually infinite Response: Flat to ground velocity at a responsitivity of 2 x 1200 V sec/m Long period corner: 20 or 360 sec second order cutoff with 0.707 critical damping Short period corner: 0.1 sec Clip level: +/- 8 mm/s ground motion (0.1 - 360 sec) Dynamic Range: > 140 dB Prices: STS-1V/VBB appr. 17.000 SFr STS-1H/VBB appr. 12.500 SFr Technical Data STS-2 Mechanical free period: Virtually infinite Response: Flat to ground velocity with a responsitivity of 2 x 750 V sec/m Long period corner: 120 sec Short period corner: > 50 Hz Clip level: +/- 13 mm/s ground velocity Dynamic Range: > 140 dB Price: STS-2 appr. 19.000 SFr If you have any questions or need more information please feel free to contact me. Torsten _____________________________________________________________________ Public Seismic Network Mailing List (PSN-L) From: Larry Cochrane Subject: Re: compare. of 3 sensors for Kermadec Date: Fri, 10 Oct 1997 15:04:19 -0700 At 08:28 PM 10/8/97 -0400, Bob Barns wrote: >Larry, > I downloaded 970920A.BKN, .LC1 & .LC3. of the Kermadec 6.9 event. >Thanks for taking the trouble of making files so that it is easy to compare >them. The comparison is very informative. (My great bad luck was to have >my rig down for this event--we had a power dip while I was out of town and >I had not provided for auto restart of SDR in AUTOEXEC.BAT.) [snip] > Since I have only a Lehman, I was delighted to see that yours was only >slightly inferior to the broadband rig. I suppose that the Berk. sensor is >in a good location (borehole?) so the similarity of the S/N must make you >feel good about your location. Information about the Berkeley sensor can be found at: http://www.seismo.berkeley.edu/seismo/bdsn/station_book/bks.html Its located in a vault, somewhere near the campus. My location is another story, and proves that you can record EQs in the city. I live a few hundred yards away from a major freeway (US 101) and to add insult to injury there is an industrial highway between my house and the freeway. On the other side of the house, about 1 1/2 mile away, are railroad tracks. For the last few months there has been some major construction work going on right down the street from me. For those of you who know the area they are demolishing the old Circle Star theater and building some office towers on the lot. When they where demolishing the theater my sensors where getting too 1/2 (~15k counts) the max counts of my 16 bit A/D converter. Now that the theater is gone, the noise during the day has reduced a little. I can see on my SDR system exactly when they stop for lunch etc. I can't wait from them to start there pile driving... They did a test one a few weeks ago and it sure drove my sensor, and my nerves (I work at home, so I'm around here when they do the work), crazy. > I have some questions:1. Since the S wave is very strong, how come the SS >and SSS seem to be absent? 2. The LQ calculates to be at about 16:56:12. >What is the nice 'blob' (do you have a better term for this?) centered at >about 16:51:48? This 'blob' has a period of about 23" and the sections >around the LQ and LR are about 16". I have a hard time seen any of the other phase myself. Not sure why... > I would greatly appreciate your repeating this exercise the next time we >have a teleseismic boomer--one which I should also get. Will do. > A suggestion for a new feature for WINQUAKE--how about a facility for >getting an RMS avg. value for a zoomed region? This would be a better >meas. of the background amplitude. Maybe you can think of something better >than RMS. I'll look into it. -Larry Cochrane Redwood City, PSN _____________________________________________________________________ Public Seismic Network Mailing List (PSN-L) From: David A Nelson Subject: Ruapehu Date: Sat, 11 Oct 1997 18:07:37 +1200 Hi all, The mountain continues to increase in activity, Today (Sat 11 Oct97 NZ) the weather cloud cleared to show large billowing plumes of toxic gas clouds rising several thousand metres above the mountain. The rumbles/booms from the crater can be heard for several kilometres and at least one skifield is closing for safety. the others will prob. follow soon. The Alert level remains at "2" 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: prewar Subject: Three Dimensional Seismograph, thoughts, and a poem! Date: Sun, 12 Oct 1997 10:15:53 +0100 Hello everyone, from the other side of the 'BIG POND'! I have just joined PSN and have started reading the archives.... WOW, it takes some time, doesn't it? As we don't suffer any large events here in England, I am using single pivot points for hor. pendulums...... Pivots are 1930's gramophone needles (which have SMOOTH, hard ground ..005 " radiused tips), sitting into hardened domed anvils, on the horizontal pendulums. (Two-90 degree opposed, for NS and EW orientation). Attempting to get swing periodicity of 60 SECONDS..... somewhat difficult to obtain with beam lengths of only 24 inches. (The vertical offset required calculates out to only .01 inches!) .015 piano wire suspension. >>>> HAS ANYBODY TRIED USING CARBON FIBRE FOR SUSPENSION? WOULD IT STRETCH? <<<<<< With a vertical seismo in-tow with the 2 horizontals, I hope to have a Three-Dimensional seismograph. Software will show SECTIONS both through earth NS and EW, and also PLAN of earth movements, in addition to normal o/p traces on VDU etc. All Hall-Effect sensing + 12 bit A/D. RE YOUR PREVIOUS CHATS ON SEISMO ADJUSTMENTS, to keep pivot points aligned EXACTLY vertically below suspension as viewed from front..... I got hold of some .75" dia ball races with a small slot ground in the o/d. These are clamped in a 3/8 bolt. (with 2 nuts each side of race) The ball race 'bolt' is horizontally mounted at top of upright, (where the piano wire is normally anchored) into a 3/8 tapped hole, and the piano suspension goes OVER the race, IN THE SLOT, and is anchored lower down, (using yet another bolt and a thrust race for up/down adjustment to wire/beam). All this gives fine ALL ROUND adjustments to beams. The bolt thread mustn't be course for smooth adjustment...(> 30 TPI). Planning to use 20x50ohm resistors in series on 240v mains, to GENTLY heat seismo enclosure....each R giving off 3watts, keeps to 75 degreeF in winter. Does anyone have any criticism/comment on this type of heating, please???? Someone mentioned last March that heat should be positioned at TOP of enclosures. ANY comment on anything above would be appreciated. I shall study your archives further. It's all very interesting. But for now, as many of you folk seem to be interested in astronomy as well as seismology, you may like to read my own SHORT, philosophical poem about these fields....... W H E N. When the earth trembles I shall be aware. When a star twinkles I shall sit and stare. When oblivion takes me I shall not care........ For in Earth AND in Heaven, I have been there. Prewar Albert Noble. Regards to all, 'over there'. (and ANYWHERE else!) _____________________________________________________________________ Public Seismic Network Mailing List (PSN-L) From: steve jones Subject: Address for Oregon Scientific? Date: Sat, 11 Oct 1997 09:21:44 -0700 Does anyone have a telephone number / email address / etc. to reach Oregon Scientific? Thanks in advance! Steve Jones _____________________________________________________________________ Public Seismic Network Mailing List (PSN-L) From: bfryer@............ (Bob Fryer) Subject: Re: Address for Oregon Scientific? Date: Sat, 11 Oct 1997 07:53:08 -0700 (PDT) Hi Steve, Address: 18383 SW Boones Ferry Rd. Tigard, OR 97224 (503) 639-8883 Bob -- Beaverton, OR -- on the Cascadia Subduction Zone >Does anyone have a telephone number / email address / etc. to reach >Oregon Scientific? Thanks in advance! > >Steve Jones ----- earthquake WARNING research ----- --- animals, people, scientific evidence --- --- http://www.teleport.com/~bfryer --- _____________________________________________________________________ Public Seismic Network Mailing List (PSN-L) From: Robert Avakian Subject: Re: HAM interested in earthquake prediction Date: Sat, 11 Oct 1997 19:52:17 -0700 Someone help me on this, but I am sure I reember the Chineeses having at least one success warning of a major quake by monitoring the behavior of flocks of ducks in the area's villages. Was this success ever reperted? Or was it serendipity? Alsso, i remeber seeing a piece on TV about the guy in LA who predicts quakes by, among other things, the number of lost pet ads in the papers. Bob GeoMonitr@....... wrote: > > Many people have been trying to duplicate the experiments > of Anthony Fraser-Smith at Stanford, by detecting > ULF signals that may be a link between earthquake > precursors and human reactions. > > I started a newsletter on the subject, GeoMonitor, > and I have all 6 years of back issues, including some > amateur circuits for ULF detection. The newsletter is now > being published by Charles Patton, 21490 Camino Arriba, > Murrieta, CA 92562; (909) 698-9657. > Good luck > VInce > > _____________________________________________________________________ > > 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: "Erich F. Kern" Subject: Drum Recorders Date: Sat, 11 Oct 1997 20:28:26 -0700 Hi All, Does anyone have a drum recorder they'd like to sell? Am willing to refurbish to some extent, but it must have the pen driver and major components. Will pick up in So. California. Please respond to my e-mail address and NOT to this list. Regards, Erich Kern ekern@......... *************************************************************** Please visit our web site at: http://www.dconn.com/FatQuartersSoftware Thank you ************************************************************** _____________________________________________________________________ Public Seismic Network Mailing List (PSN-L) From: David A Nelson Subject: Ruapehu update Date: Sun, 12 Oct 1997 17:13:23 +1200 Ruapehu today (Sun 12 Oct. NZ) did a throat clearing with its first ash eruption in this current burst of activity. The action was captured on video tape by TV news cameramen who were near the summit at the time. The Alert Level remains at 2 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: prewar Subject: Re: HAM interested in earthquake prediction Date: Sun, 12 Oct 1997 09:21:07 +0100 Hi, See Bruce Bolts book, 'Earthquakes and Geological Discovery'. Pub1993 by Scientific American Library. Chapter 8...'Forcasting Earthquakes'. (geologist in San Franscisco bay area, DID predict using lost animals!!) ....See page 182. Hope this helps. Regards, Albert Noble, (England). Robert Avakian wrote: > Someone help me on this, but I am sure I reember the Chineeses having at > least one success warning of a major quake by monitoring the behavior of > flocks of ducks in the area's villages. Was this success ever > reperted? Or was it serendipity? > > Alsso, i remeber seeing a piece on TV about the guy in LA who predicts > quakes by, among other things, the number of lost pet ads in the papers. > > > _____________________________________________________________________ Public Seismic Network Mailing List (PSN-L) From: Karl Cunningham Subject: Re: Three Dimensional Seismograph, thoughts, and a poem! Date: Sun, 12 Oct 1997 08:34:20 -0700 Greetings Prewar -- Glad to have you in the group. I'll try to comment/answer a couple of things you mentioned... >to keep pivot points >aligned EXACTLY vertically below suspension as viewed from front..... I do this by getting it close mechanically, then changing the level of the entire instrument for the final adjustment. Do you think there is a difference in performance using one technique vs. the other? >Planning to use 20x50ohm resistors in series on 240v mains, to GENTLY >heat seismo enclosure....each R giving off 3watts, keeps to 75 degreeF >in winter. Does anyone have any criticism/comment on this type of >heating, please???? Someone mentioned last March that heat should be >positioned at TOP of enclosures. ANY comment on anything above would >be appreciated. Am I understanding you correctly that you will have 60 watts total? I use 2 watts total for the heater, mounted at the top, and my enclosure is insulated on all sides except the bottom by about 2" of urethane foam. I believe the idea is to stratify the air inside the enclosure in order to reduce convection currents as much as possible. I have all the electronics located outside the enclosure to avoid convection from that. With the heater mounted at the top, the air should be the warmest at the top and coolest at the bottom, forming a smooth gradient in between. This gradient is hopefully due to mostly conduction and minimally convection. I haven't tried it, but I suppose it would be helpful to shield the heater in such a way as to minimize radiation to components below it. Hope this helps. Karl Cunningham La Mesa, CA. PSN Station #40 karlc@....... _____________________________________________________________________ Public Seismic Network Mailing List (PSN-L) From: Clark Wockner Subject: detect ble distance Date: Sun, 12 Oct 1997 13:06:11 -0700 Hi all: I seem to be missing most of the quakes others are getting. Is it because most seismic zones are so far from Illinois or is it because of some other reason? I did not record the Kermadek 6.9 a while back and I was sure I should have gotten it. What kind of distance are the rest of you getting with your Lehmans? Comments please. Thanks all Clark _____________________________________________________________________ Public Seismic Network Mailing List (PSN-L) From: barry lotz Subject: Re: detect ble distance Date: Sun, 12 Oct 1997 00:08:33 -0700 Hi Clark I live on the west coast. I can pick up 6.5 events @ 9000k most of the time. I would guess you're another 3000k to the east. It depends on how high you can get away with setting your gain and howfar you are away from the epicenter. I think where your sensor is located locally could have an effect on recording but I don't think that should affect the large teleseismic events. Most event files I've seem are < 11,000k away. I guess you will have to do the math from your location. It seems maybe you would have better luck picking up events from the east ,eg Italy,middle east etc. There are "dead" zones which others have mentioned and could probably explain there angle range better than I. I miss events because I run on a trigger system. Others use continuous recording. Which do you have? I hope that helps a little. Barry >Clark Wockner wrote: > > Hi all: > I seem to be missing most of the quakes others are getting. Is it > because most seismic zones are so far from Illinois or is it because of > some other reason? I did not record the Kermadek 6.9 a while back and I > was sure I should have gotten it. What kind of distance are the rest of > you getting with your Lehmans? Comments please. > Thanks all > Clark > > _____________________________________________________________________ > > 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: Three Dimensional Seismograph, thoughts, and a poem! Date: Sun, 12 Oct 1997 14:50:25 -0500 prewar wrote: > With a vertical seismo in-tow with the 2 horizontals, I hope to > have a Three-Dimensional seismograph. Software will show SECTIONS both > through earth NS and EW, and also PLAN of earth movements, in addition > to normal o/p traces on VDU etc. All Hall-Effect sensing + 12 bit A/D. > I would be very interested in hearing more about how you plan on viewing the 3d data. I am working on a 3 axis instrument with each axis having identical response. But I haven't any good ideas on viewing the data. -- Jim Hannon http://soli.inav.net/~jmhannon/ 42,11.90N 91,39.26W WB0TXL _____________________________________________________________________ Public Seismic Network Mailing List (PSN-L) From: TESMECO@....... Subject: Re: Ruapehu update Date: Sun, 12 Oct 1997 18:54:25 -0400 (EDT) thanks to you i am getting interested in this one i like the daily up dates thanks _____________________________________________________________________ Public Seismic Network Mailing List (PSN-L) From: barry lotz Subject: electronic oscillator Date: Sun, 12 Oct 1997 09:47:43 -0700 Hi All I have one for you . Bare with me. I would like to increase the period of a Lehman . I made a phase shift oscillator to represent an electronic pendulum. With a gain below unity, I got damping. The period of the oscillator was determined by the resistors and capacitors used. I put an external input to oscillator by attaching a coil of magnet wire. By bringing a magnet near the coil I could get the oscillator to oscillate and damp out just like an excited pendulum. I would like to replace the coil with a displacement device like an LVDT. I would then mount the LVDT on the end of a "garden gate". I would then set the natural frequency to as low as I like, electronically. The output of the oscillator would be feed back to the garden gate by a second coil, thus making the garden gate respond like the electronic oscillator. The LVDT could be measured or a third coil could be used to represent the Lehman's velocity sensor. Sound pretty Rube Golberg, but would it work? Barry _____________________________________________________________________ Public Seismic Network Mailing List (PSN-L) From: "David A. Nelson" Subject: Re: Ruapehu update Date: Mon, 13 Oct 1997 17:27:28 +1200 Hi ??, I don't know your name as you didn't sign your mail, there are a lot of us who are whish that this mountain would do a proper throat clear and really blow its top.... the last really major eruption ( say on the scale of Mt. St.Helens) from a New Zealand volcano was in 1886 when Mt. Tarawera, ~100km nth of Ruapehu, let rip causing deaths and much damage to the Native Maori and early European settlements in the region at that time. As far as I am aware it is the only eruption to cause direct loss of life in modern times. A non-eruption related lahar from Mt. Ruapehu, christmas, 1953 wiped out a railway bridge causing the passenger train to plunge to destruction with the loss of 151 lives. this was caused by ash from a small eruption, several years earlier, blocking the outlet from the crater lake and as the lake level rose the ash dam finally burst sending a huge lahar down the river. Dave At 06:54 PM 10/12/97 -0400, you wrote: >thanks to you i am getting interested in this one i like the daily up dates >thanks > 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: prewar Subject: Heating enclosures and multi-seismos. Date: Mon, 13 Oct 1997 12:42:01 +0100 Hi Karl, Many thanks for reply.....my FIRST contact outside England.....been on internet only 3 weeks, so please excuse if protocol isn't quite correct. I have to use my idea, re ball races adjust. as I have BOTH hor. Pendulums on same frame...using normal method would put one out of line, when adjusting the other, and so on. In fact, the VERTICAL seismo is also on same frame... perhaps I have troubles to come!! It was common practice many years ago to have multi-seismo mountings, so for convenience sake, I have done this. Hasten to add that frame upright is 1"x1" steel, AND braced, so its anti-flexing! Yes, 60W is correct...I have a heated insulated hut, and inside it, is a further insulated enclosure which houses 3 seismos....60W required in winter to keep this enclosure to 75F, thermostatically controlled. I assume that your own enclosure is small, or ELSE your winters are very mild, as you only need 2W. Rather nice to be so low. Noted that your heat is from TOP. I was going to put my R's all around BOTTOM perimeter, but perhaps not, after your comment. Yes, would have thought any DIRECT heat onto seismos is to be avoided at all costs. I couldn't really believe, sitting in my little hut, in the middle of England, in a tiny village, that someone half way around the world would reply. Am finding the archives a great source of info and experience... ....still reading through them ALL! (shall never have time now to get my 3 seismo monsters working!) Many thanks again for comments/advice, Regards. Albert Noble. Karl Cunningham wrote: > Greetings Prewar -- > > Glad to have you in the group. I'll try to comment/answer a couple of > things you mentioned... > > >to keep pivot points > >aligned EXACTLY vertically below suspension as viewed from front..... > > I do this by getting it close mechanically, then changing the level of the > entire instrument for the final adjustment. Do you think there is a > difference in performance using one technique vs. the other? > > >Planning to use 20x50ohm resistors in series on 240v mains, to GENTLY > >heat seismo enclosure....each R giving off 3watts, keeps to 75 degreeF > >in winter. Does anyone have any criticism/comment on this type of > >heating, please???? Someone mentioned last March that heat should be > >positioned at TOP of enclosures. ANY comment on anything above would > >be appreciated. > > Am I understanding you correctly that you will have 60 watts total? > > I use 2 watts total for the heater, mounted at the top, and my enclosure is > insulated on all sides except the bottom by about 2" of urethane foam. I > believe the idea is to stratify the air inside the enclosure in order to > reduce convection currents as much as possible. I have all the electronics > located outside the enclosure to avoid convection from that. With the > heater mounted at the top, the air should be the warmest at the top and > coolest at the bottom, forming a smooth gradient in between. This gradient > is hopefully due to mostly conduction and minimally convection. I haven't > tried it, but I suppose it would be helpful to shield the heater in such a > way as to minimize radiation to components below it. > > Hope this helps. > > 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: "David A. Nelson" Subject: Re: Heating enclosures and multi-seismos. Date: Mon, 13 Oct 1997 23:56:40 +1200 Albert Did you think about just using a 60W lightbulb, If your enclosure is metal you could put a perspex window in it and the light would let you keep an eye on the inside without having to remove the cover. Dave _____________________________________________________________________ Public Seismic Network Mailing List (PSN-L) From: "James M Hannon" Subject: Re: electronic oscillator Date: Mon, 13 Oct 1997 07:25:55 -0500 I have been thinking about a similar concept for some time. Here are some additional thoughts. What determines the mechanical period of the pendulum is the rate at which the "restoring" force increases with displacment from rest. If one were to adjust the pivot alignment so that there was no mechanical restoring force then one could replace the mechanical force with a magnet and coil being fed from the LVDT output. By adjusting the gain of this circuit one could in theory set the period to any value desired. A big problem that I see with this is that the mechanical adjustments are very minute and subject to all sorts of outside infuuences. Unless the electronics can somehow compensate for these infulences things won;t work too well. Jim Hannon gbl@....... on 10/12/97 11:47:43 AM Please respond to psn-l@............. To: psn-l@............. cc: (bcc: James M Hannon/CedarRapids/Collins/Rockwell) Subject: electronic oscillator Hi All I have one for you . Bare with me. I would like to increase the period of a Lehman . I made a phase shift oscillator to represent an electronic pendulum. With a gain below unity, I got damping. The period of the oscillator was determined by the resistors and capacitors used. I put an external input to oscillator by attaching a coil of magnet wire. By bringing a magnet near the coil I could get the oscillator to oscillate and damp out just like an excited pendulum. I would like to replace the coil with a displacement device like an LVDT. I would then mount the LVDT on the end of a "garden gate". I would then set the natural frequency to as low as I like, electronically. The output of the oscillator would be feed back to the garden gate by a second coil, thus making the garden gate respond like the electronic oscillator. The LVDT could be measured or a third coil could be used to represent the Lehman's velocity sensor. Sound pretty Rube Golberg, but would it work? Barry _____________________________________________________________________ Public Seismic Network Mailing List (PSN-L) _____________________________________________________________________ Public Seismic Network Mailing List (PSN-L) From: prewar Subject: Re: THREE DIMENSIONAL Seismograghs and software. Date: Mon, 13 Oct 1997 13:32:50 +0100 Hi Jim, T H R E E D I M E N S I O N S. I was very interested to hear that you too are building a three axis seismo 'cluster'. I do not know what sort of software you run...is it home brew, or off the shelf? What language are you running I wonder. I have to confess that I only use a 'souped up' version of BBC BASIC....B U T, it has a smashing built in assembly language facility, which can be used for any nitty gritty fast programing. In addition to all the normal seismo programming on my PC, keyboard selection to show any of the following... 1......All 3 traces from o/p of NORTH/SOUTH, EAST/WEST and VERTICAL seismos shown TOGETHER, (each one in a different colour.) 2......Above, but seperate. 3......A large full screen draw of a PLAN VIEW of earth. The NS seismo o/p controlling the vertical component of the trace, and the EW seismo controlling the horizontal. 4.......As 3 but section through earth parallel with equator. EW seosmo o/p controls horizontal draw and VERTICAL seismo, the vertical of course. 5.......As 4 but section through earth from pole to pole. This time EW seismo o/p controls horizontal and as above, and the vertical seismo, the vertical. 6........3,4 and 5 above on screen together ,(but smaller plots of course). 7........2,3,4 and 5 all on screen together, (with even smaller plots.). 8........Have an automatic rain gauge installled ( tipping bucket design). PC sums rainfull each day and shunts it to HD....Screen can also show bar graph of rain on daily/month/yearly basis. (my PC won't yet do the washing up ..... .....but I'm working on it!!) As my seismos are not yet working, I have carried out SIMULATION on my PC program, using randomly generated values for 3 seismos and all seems OK. One thing I found was that unlike the normal o/p trace, when showing 3 to 6 above, and when there is little activity. As one is constantly drawing and redrawing a trace over the same area, then confusion begins to reign on the screen. I found that this can be partly overcome by changing the colour of the draw each time the o/p from the 3 seismos is read. (in my case 50 times per sec). This gives a multi-coloured plotting which is better than using just white on a black backgnd. (Colours are randomly selected by the PC, each conversion). Also one could automatically increase the SIZE of drawings, during quiet periods......... The o/p from seismos (if 12 bit), must be divided down to fit in with the number of pixels on the screen mode used.....12bit gives over 4096 posible positions, and it is unlikely that 4096 pixels are available on PC, X or Y axis.. For example, I have +10v, 12 bit A/D converter, sampling each seismo in turn. So 5v pos o/p gives me values up to 2048. For development work I use 640x480 screen mode......so 2048 must be divided by 4 = 512. Each increment step in A/D conversion is now represented by 1 pixel with some screen area to spare. eg. 1000 o/p divided down is 250. Say next conversion reads 900. (900/4=225). SO, program draws coloured line now on VDU, from position 250 to 225. Next conversion from 225 to next position, and so on. PLEASE EXCUSE if any of this is ground you are very familiar with. Well Jim, I hope this will give you some food for thought, and help a bit. You've hit upon my FAVOURITE seismo topic.....final aim is to have 3 D hologram, showing 3D movement of earth particals, in real time or speeded up.....will probably start with a suspended table tennis ball attached to 3 servo motors . I first become interested in the above when I read a book on seismology written by the father of English seismology, Prof. Milne, in 1898 (!!). He used smoked glass to record upon, and produced great traces showing the movement of the earth as seen from above. I thought that my PC was better equiped than smoked glass , so that is what started me down this particular road to Three Dimensions. Happy T H R E E-DIMENSIONAL SEISMO'ING!! .. Regards, Albert Noble. Jim Hannon wrote: > prewar wrote: > > > With a vertical seismo in-tow with the 2 horizontals, I hope to > > have a Three-Dimensional seismograph. Software will show SECTIONS both > > through earth NS and EW, and also PLAN of earth movements, in addition > > to normal o/p traces on VDU etc. All Hall-Effect sensing + 12 bit A/D. > > > > I would be very interested in hearing more about how you plan on viewing > the 3d data. I am working on a 3 axis instrument with each axis having > identical response. But I haven't any good ideas on viewing the data. > > -- > Jim Hannon > http://soli.inav.net/~jmhannon/ > 42,11.90N 91,39.26W > WB0TXL _____________________________________________________________________ Public Seismic Network Mailing List (PSN-L) From: prewar Subject: Re: Heating enclosures. Date: Mon, 13 Oct 1997 13:44:25 +0100 Hello Dave, Yes, I have an acrylic frontage to the enclosure, but many have pointed out that my heating is excessive, so I am having a rethink. I thought that 1 lightbulb would give too concentrated a heat.....I do use 4x40w light bulbs to heat my insulated hut though, but the seismos are seperately enclosed. Thanks for suggestions from you, and all. Regards, Albert Noble (England) David A. Nelson wrote: > Albert Did you think about just using a 60W lightbulb, If your > enclosure is metal you could put a perspex window in it and the light > would let you keep an eye on the inside without having to remove the cover. > > 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: Doug Crice Subject: Re: Heating enclosures. Date: Mon, 13 Oct 1997 08:21:02 -0700 re: Heating your seismometers I would think it would be better to use DC instead of AC to heat seismometers, at least if anybody has problems with 50/60 Hz noise. I also think that a variable resistance temperature control would be better than a thermostat, both to keep the temperature constant and to eliminate the transient from the switch. There are some relatively cheap thermistors big enough to do this job in electronics catalogs. Doug Crice _____________________________________________________________________ Public Seismic Network Mailing List (PSN-L) From: "Charles R. Patton" Subject: Re: Heating enclosures. Date: Mon, 13 Oct 1997 10:00:26 -0700 Another thought for self regulating heaters is to use PTC's (also called Posistors). This is becoming the mechanism of choice for coffee brewers. The PTC is self limiting in temperature. So it smoothly transitions to a given temperature which is set by the design of the PTC itself. No EMI! They're not terribly accurate, but they are simplicity themselves. For instance I looked up one available PTC heater from Keystone Thermometrics, St.Marys, PA 15857, phone 814-834-9140 and 800-246-7019. A part number 5510-25-65-120-PTH is a 120 V 65 degree C 20 W disc .55" dia and 0.1" thick. Another company in addition to Keystone that I'm aware of that makes heater type PTC's and that you might have some luck with in small quanities is Therm-O-Disc, Inc., Midwest Components Product Group, Muskegon, MI phone 616-777-4100. I also believe TDK, Murata, and Philips components among others, make heater versions of PTC's, but they are hard to deal with unless you have a volume application or work for a big company where the salesman can slip you some samples. There are many others that supply instrument size PTC's for use in sensing applications and certain types of current limiting and resettable fuse applications. I know I've seen some of the surplus catalogs with the coffee pot elements for sale. The problem here is that they are probably set for about 120 degrees C. A bit high for your use. Electronic parts store that cater to the TV repair area usually had some PTC's that were used on color TV sets to control the deguassing coil. They would allow an amp or two to flow for a few seconds when the TV was first turned on, then due to self heating would shut down to a few milliamps while the set remained on. What their setting temperature was, I have no idea -- just the place for a quick experiment, don't you think? Anyway, good luck. Charles R. Patton _____________________________________________________________________ Public Seismic Network Mailing List (PSN-L) From: Roger Baker Subject: Re: Heating enclosures. Date: Mon, 13 Oct 1997 12:06:39 -0500 Friends, With respect to most sensitive, high resolution instrumentation, thermal drift is the #1 problem limiting measurement accuracy. Two main design options for temperature control are a variable resistor, usually a transistor in series with the heater -- versus pulse width modulated heating which is actually a very rapid on-off control. The latter is very efficient since there is very little resistive heating in the control transistor, since the power is either full on or off. You can often operate this circuit above the top frequency of the sensor. (With very small sensor packages, the transistor itself can be used as a heater, which is both convenient and efficient.) My current approach for moderately sized sensors such as my *jellybean* seismometer/gravimeter is to use pulse width modulated heaters. The heater is arrays of evenly spaced small 100 ohm or so resistors glued with silicone to the outside of the aluminum box sensor enclosure, which is then encased in styrofoam. The best temperature control and uniformity comes from having alternating layers of good thermal conductors like aluminum and poor thermal conductors like styrofoam. If possible, try to design for small size because gradients and other thermal problems increase rapidly with instrument size. Put your front end electronics in the same thermally controlled box with the sensor. Attach your thermal sensor directly to part of the heater so the thermal lag of the feedback loop is minimized. The accuracy of the system is often increased is there is standby power going into the heater so the control power merely power tops off this constant level of heat input. Also you can't get good thermal control with a low gain feedback loop; accuracy is increased as you turn up the electronic gain of the thermal feedback loop -- usually until the system becomes unstable and starts hunting or oscillating in temperature. For REALLY precise temperature control, there is not much alternative but to use several concentrically enclosed stages of rough control and precision control. Standard little Radio Shack thermistors can probably be made to sense levels of microdegrees near room temp with appropriate support circuitry and seem to work plenty well enough for most practical sensing purposes such as thermal feedback controls. --Yours, Roger Baker _____________________________________________________________________ Public Seismic Network Mailing List (PSN-L) From: prewar Subject: Re: Heating enclosures. Date: Mon, 13 Oct 1997 16:45:39 +0100 Yes Doug, Hadn't thought about AC noise....now having a rethink here. Thanks for advice from you, and everyone else, who responded to my first letter. Regards...Albert Noble. Doug Crice wrote: > re: Heating your seismometers > > I would think it would be better to use DC instead of AC to heat > seismometers, at least if anybody has problems with 50/60 Hz noise. I > also think that a variable resistance temperature control would be > better than a thermostat, both to keep the temperature constant and to > eliminate the transient from the switch. > > There are some relatively cheap thermistors big enough to do this job in > electronics catalogs. > > Doug Crice > > _____________________________________________________________________ > > 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: Brian Chesire Subject: Re: Heating enclosures. Date: Mon, 13 Oct 1997 11:31:23 -0700 Hi, A fairly good temperature contoller is the National LM3911. I've used these for everything from milliwatt heaters to 6.5KW heaters. Very versatile. The National data sheet covers it pretty well. Properly designed it can give you a very tight loop. However, When I needed really tight control, at temps over 80C, I used a pretty standard thermistor proportional circuit. This was for a precision oscillator, ie. crystal oven. The LM3911 controls the outer oven, at 55C, and the thermistor the inner. The control circuitry for the inner oven is mounted inside the outer oven which really helps overall stability. Brian, Tucson, AZ _____________________________________________________________________ Public Seismic Network Mailing List (PSN-L) From: "Daryl P. Dacko" Subject: Re: Heating enclosures. Date: Mon, 13 Oct 1997 19:19:12 -0400 At 10:00 AM 10/13/97 -0700, you wrote: >Another thought for self regulating heaters is to use PTC's (also called >Posistors). This is becoming the mechanism of choice for coffee >brewers. The PTC is self limiting in temperature. So it smoothly >transitions to a given temperature which is set by the design of the PTC >itself. No EMI! They're not terribly accurate, but they are simplicity >themselves. I've used them myself to regulate temperature on a drift-sensitive transister. They work just fine if you don't need very percise control, although I've seen mine control to within .1 deg C in an insulated oven. If you want more BTU's, just thermally bond them to a heatsink located near the top of the box. I know Newark Electronics carrys them, and for the folks overseas, Farnell could likely get them too, since they are the same company... A great idea, I didn't think of useing them in this application. It's a real boon to us folks where it's blistering hot in the summer and bitter cold in the winter - automatic heat without the expensive controller ! Daryl _____________________________________________________________________ Public Seismic Network Mailing List (PSN-L) From: Larry Cochrane Subject: Re: detectable distance Date: Mon, 13 Oct 1997 15:33:26 -0700 At 01:06 PM 10/12/97 -0700, Clark Wockner wrote: >Hi all: > I seem to be missing most of the quakes others are getting. Is it >because most seismic zones are so far from Illinois or is it because of >some other reason? I did not record the Kermadek 6.9 a while back and I >was sure I should have gotten it. What kind of distance are the rest of >you getting with your Lehmans? Comments please. > Thanks all > It could just be the distance, but you should also check the period of your sensor. If its not long enough you will not pickup the long period surface waves. I had this problem with my Lehman a while back. I wasn't getting much low freq. information so I checked the period. Sure enough, it was down to something like 6 seconds. It should have been around 16 to 20 seconds. It must have changed do to all of the re-adjustment I keep having to do to it, do to the tilting problem. -Larry Cochrane Redwood City, PSN _____________________________________________________________________ Public Seismic Network Mailing List (PSN-L) From: TESMECO@....... Subject: Re: Ruapehu Date: Mon, 13 Oct 1997 21:04:06 -0400 (EDT) looking forward to see if it will blow i hope there isnt any body to close when and if it dose thans for the history TIM. SO CAL _____________________________________________________________________ Public Seismic Network Mailing List (PSN-L) From: barry lotz Subject: Re: THREE DIMENSIONAL Seismograghs and software. Date: Mon, 13 Oct 1997 06:58:09 -0700 Hi All I haven't been following the Three Dimensional thread in detail but I think (in theory) if one has the three components of an arriving wave that it should be possible to determing the direction the wave is coming from by vector analysis. With the addition of the arrival times, one could "pinpoint" the epicenter from one station. In reality I think the waves from three directions could get pretty complicated for other than local events. Barry _____________________________________________________________________ Public Seismic Network Mailing List (PSN-L) From: Al Allworth Subject: Re: Heating enclosures. Date: Mon, 13 Oct 1997 19:06:58 -0700 (PDT) At 12:06 PM 10/13/97 -0500, you wrote: > >Friends, > With respect to most sensitive, high resolution instrumentation, >thermal drift is the #1 problem limiting measurement accuracy. > Hello group, 25 years ago I designed a temperature control which might be of interest here. The company I was working for determined the circuit to be patentable but the project we were working on was canceled and the rights were assigned to me. I didn't have the money to patent it and people were not using accurate ovens for electronics circuits any more so it never went anywhere. The temperature sensor and the heating element are one and the same. The heater is in the form of a bridge with oposite legs made of Iron wire and the other pair of Manganin wire, which has close to zero temperature coeficient. The midpoints of the bridge are connected to a diferential amplifier which drives a series transistor feeding the bridge heater from the power supply. I was able to get a temperature stability with a single enclosure of better that 1/10 of a degree with the outside temperature changing from 0 degrees to 75 degrees F. I would be happy to see someone put this to practical use. Al _____________________________________________________________________ Public Seismic Network Mailing List (PSN-L) From: JIM CRISTIANO Subject: Re: detectable distance Date: Mon, 13 Oct 1997 20:36:16 -0700 Larry Cochrane wrote: > It could just be the distance, but you should also check the period of your > sensor. If its not long enough you will not pickup the long period surface > waves. I had this problem with my Lehman a while back. I wasn't getting > much low freq. information so I checked the period. Sure enough, it was > down to something like 6 seconds. It should have been around 16 to 20 > seconds. It must have changed do to all of the re-adjustment I keep having > to do to it, do to the tilting problem. Nothin' like an old wood floor for some ultra slow rockin' and rollin'! Jim cristiano@........... _____________________________________________________________________ Public Seismic Network Mailing List (PSN-L) From: "David A. Nelson" Subject: New Station on the USA map Date: Tue, 14 Oct 1997 20:41:41 +1200 Hi all, Please welcome Robert Laney from Herndon, Va, to the group. It's good to see another east coast seismic station up and running, look for him on the USA map on my pages. 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: "David A. Nelson" Subject: MONSTER QUAKE STH PAC Date: Tue, 14 Oct 1997 22:08:13 +1200 _____________________________________________________________________ Public Seismic Network Mailing List (PSN-L) From: Stephen Paul Subject: Re: MONSTER QUAKE STH PAC Date: Tue, 14 Oct 1997 03:50:26 -0700 Dave-- What happened in the South Pacific. I am VERY concerned about anything down there, as contrary to popular theory I sincerely believe in the 'ringing bell' hypothesis, and that anything big that happens on the west side of my little Pacific plate can and will have repercussions over here in LA to NW on the other side of the rim.... Any info yet? Stephen :^) _____________________________________________________________________ Public Seismic Network Mailing List (PSN-L) From: "David A. Nelson" Subject: Re: MONSTER QUAKE STH PAC Date: Tue, 14 Oct 1997 23:03:58 +1200 Stephen, still waiting for posting to USGS bulletin page. event ~5.5 minutes from my which puts it in the New Calidonia =---- Fiji regional distance and the amplitude suggests M7.9 --- 8.5 largest amplitude I have recorded for this distance. Tony in Hawaii mailed me a short time ago He also recorded it with large amplitude (largest he has so far recorded Dave At 03:50 AM 10/14/97 -0700, you wrote: >Dave-- > >What happened in the South Pacific. I am VERY concerned about anything >down there, as contrary to popular theory I sincerely believe in the >'ringing bell' hypothesis, and that anything big that happens on the west >side of my little Pacific plate can and will have repercussions over here >in LA to NW on the other side of the rim.... > >Any info yet? > >Stephen :^) > > > >_____________________________________________________________________ > >Public Seismic Network Mailing List (PSN-L) > >To leave this list email listserver@............. with the body of the >message: leave PSN-L > > 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: peaches@............ (Donna Whitaker) Subject: Re: MONSTER QUAKE STH PAC Date: Tue, 14 Oct 1997 01:17:11 -1000 (HST) Dave, CDIDC has it in the Fiji Islands region at M6.2 but thats got to be way low. Tony >Stephen, > still waiting for posting to USGS bulletin page. > > event ~5.5 minutes from my which puts it in the New Calidonia =---- Fiji >regional distance and the amplitude suggests M7.9 --- 8.5 largest >amplitude I have recorded for this distance. > > Tony in Hawaii mailed me a short time ago He also recorded it with >large amplitude (largest he has so far recorded > >Dave > > >At 03:50 AM 10/14/97 -0700, you wrote: >>Dave-- >> >>What happened in the South Pacific. I am VERY concerned about anything >>down there,