Subject: PSN - NEIC Problems!
From: "Rex Klopfenstein, Jr" rklopfen@.........
Date: Wed, 30 Jun 1999 09:23:54 -0400
Is it my location or is there problem with the NEIC Near Realtime
Reporting Webpage? Last night and today I couldn't get a response! I
have been using http://wwwneic.cr.usgs.gov
Rex Klopfenstein, Jr.
Bowling Green, OH
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Subject: Placer 400 problems
From: Phil Giannini pgiannini@........
Date: Wed, 30 Jun 1999 08:07:13 -0700
Hi John,
I bought a Placer 400 some time back with plans to use it with my
remote gear for both location accuracy and time lock. I used it once on
a trip to the Geysers just for a location fix when I first got it to try
it out and it worked great. I have plans to tie it into my recorder for
time locking, but I've been busy and haven't gotten back to that
project.
I sort of remember that as long as the back up battery (the 9v one)
is good it is suppose to fire right up and remember where it was last
and the time should be fairly close so that it will update quickly. I
don't have the spec sheet handy here at work, but I am not sure if it
will be totally happy with that 10 volts for the main power, it might
really want 12. The other thing is the power from that wall
transformer/power supply clean? It might have some hum on it and that
might be what's corrupting your data.
The only problem I think I may have with mine is with the one second
pulse on pin 9 of the connector plug. Maybe you can answer a question
for me? That being, what does your 1 second pulse look like on that pin.
Mine is a very short very low level differentiated pulse or spike like
looking thing, not at all looking like what I would have expected there.
I don't know if mine is defective in that area or if that is what it is
suppose to look like. Like I said I never got much of a chance to play
with it but, I did open up the box looking around for that pulse and
remember that there wasn't much inside. It's been a long time, but I
can't say that I remember seeing any little clock battery in there. Wish
I could be more help.
Regards, Phil
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Subject: R: PSN - NEIC Problems!
From: "Francesco" franuc@......
Date: Wed, 30 Jun 1999 17:06:51 +0200
Hello Rex,
last night I had the same problem for calibrating Pakistan event.
Many time, the NEIC web page or the Neic quake finger is down!
Francesco
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Subject: Re: Placer 400 problems
From: The Lahrs JohnJan@........
Date: Wed, 30 Jun 1999 10:09:28 -0600
Phil,
Thanks for the feedback on your Placer 400. I finally figured out
why I was getting the messages re battery backup. I had connected
the main power and the back up power at the same time. Although
I had turned GPPSK.EXE on and off many times, I had never turned
off the main power, leaving just the battery backup to run the
system. Until you do that once, the system doesn't know that there
is a battery backup installed.
Will the unit run OK from the 12V car lighter socket, or does the
voltage need to be conditioned with a DC-DC converter?
Is GPSSK.EXE the program you used at the Geysers?
Some time ago I looked at pin 9 on the scope. There was a very short
spike every second. I was hoping to be able to count up perhaps
15 minutes of spikes and then put out a 15 minute mark (trace offset)
on my digital record. This would give me a clock correction every
15 minutes. The problem is that I don't know how to build such
a circuit. Any ideas out there?
Cheers,
John
PS. Re the NEIS web problems, I know that there were network
problems in the building yesterday. They must have gotten worse!
At 08:07 AM 6/30/99 -0700, Phil wrote:
>Hi John,
> I bought a Placer 400 some time back with plans to use it with my
>remote gear for both location accuracy and time lock. I used it once on
>a trip to the Geysers just for a location fix when I first got it to try
>it out and it worked great. I have plans to tie it into my recorder for
>time locking, but I've been busy and haven't gotten back to that
>project.
> I sort of remember that as long as the back up battery (the 9v one)
>is good it is suppose to fire right up and remember where it was last
>and the time should be fairly close so that it will update quickly....
>... what does your 1 second pulse look like on that pin.
>Mine is a very short very low level differentiated pulse or spike like
>looking thing....
* John C. and Jan H. Lahr *
* JohnJan@........ *
* 1925 Foothills Road *
* Golden, Colorado 80401-1718 *
* (303) 215-9913 *
* http://lahr.org/john-jan *
* AOL version of homepage: *
* http://lahr.org/john-jan/homepage.html *
* http://giseis.alaska.edu/lahr *
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Subject: Re: Placer 400 problems
From: "Kevin J. Rowett" krowett@..........
Date: Wed, 30 Jun 1999 09:24:43 -0700
>
>
>Some time ago I looked at pin 9 on the scope. There was a very short
>spike every second. I was hoping to be able to count up perhaps
>15 minutes of spikes and then put out a 15 minute mark (trace offset)
>on my digital record. This would give me a clock correction every
>15 minutes. The problem is that I don't know how to build such
>a circuit. Any ideas out there?
It's a 1 pulse per second output, sync'ed to GPS time. (1PPS).
15 minutes is 900 counts at a frequency of 1Hz. A 10 bit counter,
with a bit of logic to reset at 899 would be the ticket.
KR
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Subject: Re: Using Lasers
From: John Taber taber@.............
Date: Thu, 1 Jul 1999 11:59:01 +1200 (NZST)
Denny,
There is a group here in New Zealand that has a fancy ring laser in
an old WWII bomb shelter. They have shown that it is capable of
recording seismically generated rotations. It's not the sort of
laser you could build at home and the papers that they list are
rather technical but there are some good pictures of the laser and
the "cave". Their main web site is
http://www.phys.canterbury.ac.nz/~physges/
Cheers,
John
Denny Goodwin wrote:
>
> Anyone using lasers for detection - if so, how?
>
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Subject: Re: Old PC Convertible - can it be upgraded?
From: Steve Hammond shammon1@.............
Date: Thu, 01 Jul 1999 04:26:30 -0700
Hi Ted, take it... I seem to remember the one at the meeting could also
run off of a battery pack.
Let's just talk about the standard PC Convertible. It is a PC XT with a
mono CGA display in it and standard XT keyboard. You can put 1.44's in
it, however you need set144 from the PC tools disk to make it work.
Fr4om a HDD standpoint, you could put in an a small 20Meg MFM drive and
controller card. Come see me and I'll fix you up. BTW, I have one
already setup like this and another one on for parts. Workes fine with
an DACA card and you can collect samples at 60SPS. The other thing you
can do is go to fry's and buy a small footprint motherboard. It will
need to have the old style P8-P9 power connectors however and support
CGA.
Regards, Steve PSN San Jose
Ted Blank wrote:
>
> I have a friend who will give me an old PC Convertible (or "luggable" as
> we used to call it). I remember someone at the last PSN meeting had one
> which was customized for portable quake recording.
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Subject: Old PC Luggable
From: Phil Giannini pgiannini@........
Date: Thu, 01 Jul 1999 07:33:51 -0700
Hi Again Guys,
FYI......
If you are looking for neat old stuff like that "Luggable", CHEAP
mother boards, and just lots of real cool stuff that tinkers like us are
always messing around with, Mike Quinn's Electronics in San Leandero is
the place to go. It is a tinkers paradise. The place is just of 98th
Ave. on the southwest side of the 880. Jay, the guy who runs the place,
is helpful, very knowledgeable, and his prices are right.
Regards, Phil
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Subject: Placer 400 problems
From: Phil Giannini pgiannini@........
Date: Thu, 01 Jul 1999 08:34:09 -0700
Hi again John and All,
Yes, the Placer 400 runs nicely from 12 vdc. It was originally
designed to be used in commercial vehicles to track their locations, so
it's a happy guy on 12 volts.
I used the GPSSK software to get a readout of my location and a
time setting when I used it at the Geysers. But, I didn't have my
recorder locked to it because my system is currently setup to do WWV
tone lock. I did use the time reading from the Placer though to set the
computer clock as I couldn't pickup WWV where I was. Now don't hold me
to this, but I don't think you will need the GPSSK software running if
you are just going to be using the Placer 400 for time lock once the
receiver is locked up. Reason being, I'm almost positive that the 1
second pulse comes out even without that software running. I do think,
however, that you will have to clean up the 1 second pulse some though
before you can use it to trigger a counter or other digital circuitry
properly. Especially now that I hear your 1 second signal is kind of
crummy looking too.
Phil
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Subject: Re: Placer 400 problems
From: "James M Hannon" jmhannon@............................
Date: Thu, 1 Jul 1999 10:43:11 -0500
John,
Your description of the 1 PPS signal (small amplitude and bipolar) sounds
like you are either looking at to wrong pin or there is a broken wire
somewhere. I see this sort of signal when probing with a scope and happen
to be looking at an adjacent wire that is not connected to anything. The
capacitance between the wires will cause you to see a signal that looks
like what you described. The 1 PPS signal is typically a pulse just a few
microseconds in duration but should not be bipolar.
A bad scope probe will also cause the pulse to look bad.
Jim Hannon
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Subject: Re: Placer 400 problems
From: John Lahr lahr@...................
Date: Thu, 1 Jul 1999 12:53:56 -0600 (MDT)
Hi Phil,
When you used GPPSK to get the time, was it very accurate?
I think it only redisplays the time every few seconds, although
it might be possible to speed this up.
Kevin suggested using a 10 bit counter and some logic
elements to get a 15 minute pulse. Can anyone recommend
a book that would show how to design such a circuit? Or,
does anyone have a similar circuit that would only need
minor modifications?
Thanks,
JCLahr
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Subject: Golden PSN Meeting
From: The Lahrs JohnJan@........
Date: Thu, 01 Jul 1999 22:30:45 -0600
After the PSN meeting here in Golden, I found a plastic cap that could
have come off of one of the show-and-tell items at my house.
The cap is 1.5" in diameter and 0.5" high. There is a 2mm diameter
hole in the center and the outside rim has 6 vertical bumps. The bottom
surface is skuffed, so this may have formed the base of one leg of
an instrument.
John
* John C. and Jan H. Lahr *
* JohnJan@........ *
* 1925 Foothills Road *
* Golden, Colorado 80401-1718 *
* (303) 215-9913 *
* http://lahr.org/john-jan *
* AOL version of homepage: *
* http://lahr.org/john-jan/homepage.html *
* http://giseis.alaska.edu/lahr *
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Subject: 15-minute counter for Placer 400
From: The Lahrs JohnJan@........
Date: Fri, 02 Jul 1999 04:38:58 -0600
Kevin,
That would be great! I'm not in a big hurry, as I'm dealing with
a herniated disk right now and probably will not get my seismic system
set up again for another month or so. My plan is to continue using
a one-channel AD (DaTaq) which is fed by coil/magnet/amplifier from
my home-built Lehman. DaTaq stamps the files with the computer time.
I would like to offset the trace every fifteen minutes for about
10 seconds. To do this I'll add a summing amplifier after the final
stage of the amplifier. Once I get the phase of the fifteen-minute
marks correct, they will be used to derive four clock corrections per hour.
Thinking about it now, it may be tricky getting the fifteen-minute
marks to go off on the minute. One option would be have a push button
that would set the counter to 899 and block the ticks from the GPS unit
when it is held down. The button could be released just before
the 0-, 15-, 30-, or 45-minute mark to set the phase of the ticks.
Thanks for this offer! Of course I'll reimburse you for the parts,
and post the schematic when it's working in case anyone else wants to
try a similar scheme.
John,
How big of a hurry are you in? What kind of output do you need the
15 minute pulse to be? What is it going into?
I'll breadboard a circuit and send it to you, but, it will be a couple of
weeks before I can get it into the mail.
KR
>Kevin suggested using a 10 bit counter and some logic
>elements to get a 15 minute pulse. Can anyone recommend
>a book that would show how to design such a circuit? Or,
>does anyone have a similar circuit that would only need
>minor modifications?
* John C. and Jan H. Lahr *
* JohnJan@........ *
* 1925 Foothills Road *
* Golden, Colorado 80401-1718 *
* (303) 215-9913 *
* http://lahr.org/john-jan *
* AOL version of homepage: *
* http://lahr.org/john-jan/homepage.html *
* http://giseis.alaska.edu/lahr *
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Subject: Re: Placer 400 problems - a counter circuit suggestion
From: "Charles R. Patton" patton@..........
Date: Fri, 02 Jul 1999 09:44:20 -0700
Hi,
If you go to the Texas Instruments site:
http://www.ti.com/sc/docs/products/logic/cd4059a.html
you will find the spec sheet for a CD4059A, a 16 bit, programmable
divider IC. This will make it extremely simple to do your divide by any
number from 3 to 15,999. Mouser Electronics is selling them for $3.58.
Just add 16 bits worth of DIP switches together with pull-ups, one
button for preset (reset to zero) and you are done. Since it is a CD
part, you can run it on anything from 3 to 15V. Take a look at the spec
sheet, and if you still have a problem, send me a note, and I=92ll draw u=
p
a schematic and post it.
Charles R. Patton
P.S., I=92m posting from work, so if you want to direct email, the addres=
s
below will work better over the weekend.
charles.r.patton@........
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Subject: Re: Old PC Convert
From: Ted Blank tblank@..........
Date: Fri, 2 Jul 1999 11:20:18 -0700 (PDT)
Hey Phil, you did a hell of a job. But wouldn't it have been easier to
just move the handle from the luggable over that PC where you got all the
parts? :-)
IF you have any info on the power supply mods, can you send it? Thanks.
Ted Blank
San Jose, California
On Tue, 29 Jun 1999, Phil Giannini wrote:
> Hi Ted and Gang,
> I was the one with the converted luggable. But I cheated and
> completely gutted the machine and installed a 386 DX40 mother board, 9
> inch B/W VGA monitor, 500 meg hard drive, 1.44 floppy, and still had
> room to build in one of Larry's demod boards. I also modified the power
> supply to work on AC or from 12VDC so it could be operated in remote
> locations from a 12v car battery when no AC power is available. An AT
> type keyboard was modified to fit in the luggable's fold down
> door/bottom, as the luggable originally used an XT type keyboard that
> wouldn't work on the 386 mother board.
> The system is using the PC Labs 12 bit A/D board modified for time
> lock running Larry's SDR software and Winquake. There is also a 33.6
> modem on board so I can upload any captured events if there is a phone
> line available at the remote location.
>
> On another note, I noticed that the station names on the list for
> me are incorrect. I don't know if that is just a typo or if they are
> actually listed that way. If so can they be corrected? They should be
> SFN and SFZ, and I would like to reserve SFE for the partly finished E/W
> sensor I am building. Also the TVZ listing can be removed from the list
> as that system has been retired. Thanks and sorry for any inconvenience
> that may have created.
>
>
> Regards, Phil
>
> SFN & SFZ
>
>
> _____________________________________________________________________
>
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>
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Subject: Packrat humor in a garage clean out endeavor...
From: meredith lamb psnseismograph52@..........
Date: Fri, 02 Jul 1999 15:43:29 -0600
Hi all,
I've been trying to clean up my garage for awhile; in the course
of this trauma, humor springs forth, and I thought you might
need this inspiration, from my brother and sister.....
"Joan R." wrote:
> Hi guys,
>
> Can hardly believe it's July 1 already. Or, as the saying goes, "Time
> flies like an arrow and fruit flies like bananas."
>
> There are rules to successful trashing, Meredith. The basic rule is, if
> you've had stuff stored for 10 years, and you haven't gotten around to
> using it, then odds are you never will, so pitch it. Trashing is best when
> you're really angry about something or at someone. If you're relaxed and
> feeling all sentimental, you tend to want to hang onto stuff or
> optimistically think there's still a use for or a way to fix that broken
> appliance or furniture. Pressure helps. Like, if you're expecting a fire
> hazard inspector. It's helpful if you have one or more do-it-yourselfer
> friends. They always can see possibilities in your junk, covet it, and are
> thrilled when you give it to them. It helps if you make them think you're
> doing it out of the goodness of your heart. Don't build shelves or buy
> storage bins or cabinets. That just encourages clutter, because true trash
> collectors never get around to sorting and putting stuff away. If you sort
> stuff and put them away, you'll never be able to find something when or if
> you actually want it, and you'll wind up buying more stuff. Don't quit
> when you get tired. You throw out more when you get too tired to think if
> you really want to keep it.
>From Bob Lamb;
"Hi Joan & Meredtih...will the trashing ever stop? Actually I
do believe and follow your philosofee (ha) Joan, and do OK up
to a certain point.... the targeted trash object can be in my hand
ready to be tossed out... but I freeze up, can't let go of it...fingers
holding tight!!! (and) Now I'am curious..have you tossed
something out, but then changed your mind and retrieved it??"
Perhaps the most traumatizing potential Rule 1 is: Throw out the
top 10 most coveted piles....then the rest will come much easier.
Trouble is....the best isn't the usual humdrum homey type stuff,
if you're a typical experimenter....but, if nobody else knows
that; you maybe looked upon as being courageous is you do trash out
the homey stuff....first. I think I'll be courageous.
Meredith Lamb
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Subject: Distant quake coming...
From: meredith lamb psnseismograph52@..........
Date: Fri, 02 Jul 1999 19:51:00 -0600
Hi all,
Looks like a distant quake coming in....about 01:47 p wave
utc. iP.
Meredith Lamb
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Subject: Distant quake coming in...
From: meredith lamb psnseismograph52@..........
Date: Fri, 02 Jul 1999 19:54:04 -0600
Hi all,
Fair size L waves coming 01:51 utc. approximately.
This looks like it will take some time to die down.
Meredith Lamb
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Subject: Re: Distant quake coming...
From: barry lotz gbl@.......
Date: Fri, 02 Jul 1999 19:01:30 -0700
Meredith
Picking it up strong here
Barry
meredith lamb wrote:
> Hi all,
>
> Looks like a distant quake coming in....about 01:47 p wave
> utc. iP.
>
> Meredith Lamb
>
> _____________________________________________________________________
>
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>
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Subject: Re: Distant quake coming in...
From: david alexander dalex@...........
Date: Fri, 02 Jul 1999 19:02:39 -0700
don't have any instruments here but the seat of my pants says it was in
the north puget sound area. maybe an aftershock of the vancouver island
quake of this morning.
dave
meredith lamb wrote:
>
> Hi all,
>
> Fair size L waves coming 01:51 utc. approximately.
>
> This looks like it will take some time to die down.
>
> Meredith Lamb
>
> _____________________________________________________________________
>
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>
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> message: leave PSN-L
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Subject: Distant quake coming in...
From: meredith lamb psnseismograph52@..........
Date: Fri, 02 Jul 1999 20:04:12 -0600
Barry,
Perhaps, a aftershock of the Vancouver Island quake of earlier
on the 2nd? Red Puma has nothing yet. If its strong there and
so-so here, perhaps it is around Vancouver? Could be any
where of course.
Meredith Lamb
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Subject: Re: Distant quake coming in...
From: barry lotz gbl@.......
Date: Fri, 02 Jul 1999 19:14:00 -0700
I'll get it from SDR, get distance and see if we can triangulate
Barry
meredith lamb wrote:
> Barry,
>
> Perhaps, a aftershock of the Vancouver Island quake of earlier
> on the 2nd? Red Puma has nothing yet. If its strong there and
> so-so here, perhaps it is around Vancouver? Could be any
> where of course.
>
> Meredith Lamb
>
> _____________________________________________________________________
>
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>
> To leave this list email listserver@.............. with the body of the
> message: leave PSN-L
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Subject: Re: Distant quake coming in...
From: meredith lamb psnseismograph52@..........
Date: Fri, 02 Jul 1999 20:07:27 -0600
david alexander wrote:
> don't have any instruments here but the seat of my pants says it was in
> the north puget sound area. maybe an aftershock of the vancouver island
> quake of this morning.
> dave
David,
Where are you....in the Northwest perhaps....feel anything?
Meredith Lamb
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Subject: Re: Distant quake coming in...
From: david alexander dalex@...........
Date: Fri, 02 Jul 1999 19:09:08 -0700
this from the univ of washington site.
Time of Occurrence (GMT): Saturday July 3, 1999 at 01:43:54.36 Z
Depth (km) 39.87
Magnitude (Mc) 3.5
Location 47.0638N 123.4682W
6.8 km N of Satsop, WA
dave..
meredith lamb wrote:
>
> Barry,
>
> Perhaps, a aftershock of the Vancouver Island quake of earlier
> on the 2nd? Red Puma has nothing yet. If its strong there and
> so-so here, perhaps it is around Vancouver? Could be any
> where of course.
>
> Meredith Lamb
>
> _____________________________________________________________________
>
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>
> To leave this list email listserver@.............. with the body of the
> message: leave PSN-L
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Subject: Distant quake coming in...
From: meredith lamb psnseismograph52@..........
Date: Fri, 02 Jul 1999 20:19:42 -0600
Barry and David,
Red Puma has 3 close locations...Washington/Van Courver/
British Columbia. Tentative mag 5.6.
Meredith Lamb
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Subject: Re: Distant quake coming in...
From: barry lotz gbl@.......
Date: Fri, 02 Jul 1999 19:38:39 -0700
Meredith
It seem like it's south of vancouver Isl I read it at 1050k where
vancouver Isl was about 1300k from me.
Barry
meredith lamb wrote:
> Barry and David,
>
> Red Puma has 3 close locations...Washington/Van Courver/
> British Columbia. Tentative mag 5.6.
>
> Meredith Lamb
>
> _____________________________________________________________________
>
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>
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> message: leave PSN-L
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Subject: PNW EQ
From: The Lahrs JohnJan@........
Date: Fri, 02 Jul 1999 20:35:38 -0600
The USGS NEIS has:
47.08 N
-123.46 W
40.6 KM
Mag 5.5
1999/07/03 01:43:54
From this page of seismograms
http://aslwww.cr.usgs.gov/Seismic_Data/heli2.htm
it was located only slightly closer to Albuquerque than
to College, Alaska.
John
* John C. and Jan H. Lahr *
* JohnJan@........ *
* 1925 Foothills Road *
* Golden, Colorado 80401-1718 *
* (303) 215-9913 *
* http://lahr.org/john-jan *
* AOL version of homepage: *
* http://lahr.org/john-jan/homepage.html *
* http://giseis.alaska.edu/lahr *
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Subject: EQ Alarm
From: The Lahrs JohnJan@........
Date: Fri, 02 Jul 1999 20:45:22 -0600
My alarm and eq map of NEIS quakes on this page:
http://geohazards.cr.usgs.gov/fingview/fingerview.html
worked to alert me to the new location. If you use
Netscape it should work right away. With MSIE you will
need to download a file from the MS page before it will
work.
John
* John C. and Jan H. Lahr *
* JohnJan@........ *
* 1925 Foothills Road *
* Golden, Colorado 80401-1718 *
* (303) 215-9913 *
* http://lahr.org/john-jan *
* AOL version of homepage: *
* http://lahr.org/john-jan/homepage.html *
* http://giseis.alaska.edu/lahr *
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Subject: Wow! John Lahr....that Viewer is great!
From: meredith lamb psnseismograph52@..........
Date: Fri, 02 Jul 1999 21:13:29 -0600
John,
Looks like I'll have to reference your Recent Seismicity Viewer
from now on. Perhaps it will be faster than Red Puma. I didn't
know this even existed before. I note it was overwhelmed at
the web site after your notice.....got down to 0 to 47 bytes per
second....but it eventually all came through.
Hope your herniated disk can be corrected sometime with little
down time.
Wonder if Edward Cranswick is going to Washington for this
quake series?
Interesting communication on this quake....it seems there is
a number of people checking PSN, and participating...nice.
Meredith Lamb
_____________________________________________________________________
Public Seismic Network Mailing List (PSN-L)
Subject: Re: PNW EQ
From: barry lotz gbl@.......
Date: Fri, 02 Jul 1999 20:21:06 -0700
John
Your note brings up an interesting question. Are, or should, the
recordings normalized or at the same gain? If they were then one could make
a better determination of the event general location.
Barry
The Lahrs wrote:
>
> >From this page of seismograms
>
> http://aslwww.cr.usgs.gov/Seismic_Data/heli2.htm
>
> it was located only slightly closer to Albuquerque than
> to College, Alaska.
>
> John
>
_____________________________________________________________________
Public Seismic Network Mailing List (PSN-L)
Subject: Re: PNW EQ
From: The Lahrs JohnJan@........
Date: Fri, 02 Jul 1999 21:40:56 -0600
Barry,
On the Albuquerque all of the seismograms have the same gain,
at least it looked that way to me on a quick glance. The gain
is specified along the lower edge of each record as 3000 @ .02 Hz.
Meredith,
Red Puma will generally be the first site with some preliminary
information. I'm just plotting the reviewed NEIS solutions that
are put out on the finger listing. I noticed tonight that the alarm
range twice when there was not an new earthquake added. This may
be due to one of the eq solutions being modified, so the parameters have
changed in some way. I'm still looking into this.
John
* John C. and Jan H. Lahr *
* JohnJan@........ *
* 1925 Foothills Road *
* Golden, Colorado 80401-1718 *
* (303) 215-9913 *
* http://lahr.org/john-jan *
* AOL version of homepage: *
* http://lahr.org/john-jan/homepage.html *
* http://giseis.alaska.edu/lahr *
_____________________________________________________________________
Public Seismic Network Mailing List (PSN-L)
Subject: sound picture?
From: "Bonnie Schafer" bschafer@.........
Date: Fri, 2 Jul 1999 21:09:28 -0700
Hi, was wondering if there is any way I might set up a sound signal that
would set off some kind of audible alarm when there is a quake occurring? I
would need to do this as I can't see the charts and seismograms and such. I
thought of trying to find a seismometer but don't know where to look or how
to go about making one. Also, would have to find a place to set it up where
there isn't so much vibration. I live near the freeway and trucks and cars
are always vibrating the house--funny birds can tell the difference. When
it is dark and we have a quake I have to get up and calm them down yet when
a truck or car goes by they don't take notice of them.
Bonnie the crafty crafter
_____________________________________________________________________
Public Seismic Network Mailing List (PSN-L)
Subject: GPS's
From: Karl Cunningham karlc@.......
Date: Sat, 03 Jul 1999 00:21:35 -0700
Greetings --
The San Diego Museum of Natural History is interested in buying a GPS for
timing for their seismometer, which will be running SDR.
The GPS must accomodate an external active antenna that can be located on
the roof, at then end of about 150 feet of cable. Of course, cost is a
factor too.
Does anyone have any recommendations on a GPS I could suggest to the museum?
Karl Cunningham
La Mesa, CA.
PSN Station #40
karlc@.......
_____________________________________________________________________
Public Seismic Network Mailing List (PSN-L)
Subject: EQ Alarm down now!
From: The Lahrs JohnJan@........
Date: Sat, 03 Jul 1999 03:54:58 -0600
I just noticed that the alarm is not working and when I checked
at work the critical computer has apparently crashed! I'm not sure
how soon someone will get it going again, so for now my alarm
and plotting programs will not work!
********
The alarm and eq map of NEIS quakes on this page:
http://geohazards.cr.usgs.gov/fingview/fingerview.html
worked to alert me to the new location. If you use
Netscape it should work right away. With MSIE you will
need to download a file from the MS page before it will
work.
John
John C. Lahr
POB 1529
Golden, CO 80402
(303) 215-9913
http://lahr.org/john-jan
I am only one
But still I am one.
I cannot do everything
and because I cannot
do everything
I will not refuse
to do the something
that I can do.
Edward Everette Hale
_____________________________________________________________________
Public Seismic Network Mailing List (PSN-L)
Subject: Re: sound picture?
From: The Lahrs JohnJan@........
Date: Sat, 03 Jul 1999 04:06:24 -0600
Hi Bonnie,
How do you "read" the PSN postings? Do you use a translator from
text to voice? The browser-based alarm I mentioned earlier would
notify you of new earthquakes on the NEIS finger listing, which is
on the NEIS web site here:
http://wwwneic.cr.usgs.gov/neis/bulletin/bulletin.html
The alarm has a graphical interface requiring a mouse click to
reset it after an earthquake, so that may be a problem. Also,
it would go off for any reviewed solution anywhere in the world!
Another option would be to set up a seismic system using Larry's
AD board and software. You could use a 4.5 Hz geophone for
detecting local events. I haven't used his program, so don't
know for sure if you could set up the trigger settings to
alarm on a local earthquake but not a bus. Birds may be smarter!
Also, Larry can let you know if the system has an audible alarm.
Sounds like an interesting project.
John
At 09:09 PM 7/2/99 -0700, you wrote:
>Hi, was wondering if there is any way I might set up a sound signal that
>would set off some kind of audible alarm when there is a quake occurring?
>
>Bonnie the crafty crafter
* John C. and Jan H. Lahr *
* JohnJan@........ *
* 1925 Foothills Road *
* Golden, Colorado 80401-1718 *
* (303) 215-9913 *
* http://lahr.org/john-jan *
* AOL version of homepage: *
* http://lahr.org/john-jan/homepage.html *
* http://giseis.alaska.edu/lahr *
_____________________________________________________________________
Public Seismic Network Mailing List (PSN-L)
Subject: Satsop/Aberdeen WA EQ
From: SW6079@.......
Date: Sat, 3 Jul 1999 09:38:31 EDT
Got a great record on it here in Bothell. If anyone would like it, e-mail me
at sw6079@ aol.com
_____________________________________________________________________
Public Seismic Network Mailing List (PSN-L)
Subject: Re: GPS's
From: "Rex Klopfenstein, Jr." rklopfen@.........
Date: Sat, 03 Jul 1999 10:00:29 -0400
Look at Larry's suggested GPS system on his website. I would guess that it
costs about $200 total for parts. Does require some assembly!
Karl Cunningham wrote:
> Greetings --
>
> The San Diego Museum of Natural History is interested in buying a GPS for
> timing for their seismometer, which will be running SDR.
>
> The GPS must accomodate an external active antenna that can be located on
> the roof, at then end of about 150 feet of cable. Of course, cost is a
> factor too.
>
> Does anyone have any recommendations on a GPS I could suggest to the museum?
>
> 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
--
Rex Klopfenstein, Jr.
Bowling Green, OH
rklopfen@.........
www.wcnet.org/~rklopfen
_____________________________________________________________________
Public Seismic Network Mailing List (PSN-L)
Subject: Re: GPS's
From: "Rex Klopfenstein, Jr." rklopfen@.........
Date: Sat, 03 Jul 1999 10:00:29 -0400
Look at Larry's suggested GPS system on his website. I would guess that it
costs about $200 total for parts. Does require some assembly!
Karl Cunningham wrote:
> Greetings --
>
> The San Diego Museum of Natural History is interested in buying a GPS for
> timing for their seismometer, which will be running SDR.
>
> The GPS must accomodate an external active antenna that can be located on
> the roof, at then end of about 150 feet of cable. Of course, cost is a
> factor too.
>
> Does anyone have any recommendations on a GPS I could suggest to the museum?
>
> 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
--
Rex Klopfenstein, Jr.
Bowling Green, OH
rklopfen@.........
www.wcnet.org/~rklopfen
_____________________________________________________________________
Public Seismic Network Mailing List (PSN-L)
Subject: Re: sound picture?
From: "Bonnie Schafer" bschafer@.........
Date: Sat, 3 Jul 1999 08:04:42 -0700
Hi, thank you so much for writing. I really appreciate it.
I use a speech synthesizer that hooks to my computer--mine is an internal
one--a card that goes inside the PC. Anyway, it will read text just fine
but does not read graphics at all. What I am looking for--and there
probably isn't such a thing--but an alarm to sound at the time of a quake
occurring and then text to appear telling me in plain text where the quake
occurred and the epicenter and magnitude of the event. I suspect that there
isn't such a thing but it sure would be interesting. I thought of getting a
seismometer but don't know where I would put it as this mobile home vibrates
all the time from trucks and cars from the freeway.
Again, thanks so much for writing. By the way, if you have any more
questions please don't hesitate to ask I don't mind at all and would be glad
to answer any questions you may have.
I
Bonnie the crafty crafter
_____________________________________________________________________
Public Seismic Network Mailing List (PSN-L)
Subject: Re: GPS's
From: barry lotz gbl@.......
Date: Sat, 03 Jul 1999 09:06:14 -0700
Hi Karl
It's not a GPS and it requires a small circuit but I have been using the
Radio Shack clock with SDR for awhile and it works well (~$40). I have the
antenna at the end of a 30' cable to locate it in an area of good reception.
Barry
Karl Cunningham wrote:
> Greetings --
>
> The San Diego Museum of Natural History is interested in buying a GPS for
> timing for their seismometer, which will be running SDR.
>
> The GPS must accomodate an external active antenna that can be located on
> the roof, at then end of about 150 feet of cable. Of course, cost is a
> factor too.
>
> Does anyone have any recommendations on a GPS I could suggest to the museum?
>
> Karl Cunningham
> La Mesa, CA.
> PSN Station #40
> karlc@.......
>
_____________________________________________________________________
Public Seismic Network Mailing List (PSN-L)
Subject: Re: sound picture?
From: The Lahrs JohnJan@........
Date: Sat, 03 Jul 1999 12:19:24 -0600
Bonnie,
Do you use a PC? Is it possible to use a DOS window?
If you install java on a PC, then I could write
a simple program that would periodically check for new events in
California and sound an alarm if one is reported. Then you
could listen to the file of recent events to get the coordinates,
time and location. The file format would be like this,
which is the "finger" format. These are the last two events reported
by Caltech.
99/07/03 00:20:15 33.96N 116.82W 18.5 2.3ML A 4 mi. NE of
Banning, CA
99/07/03 01:26:47 37.18N 118.40W 5.5 3.0ML C 7 mi. W of Big
Pine, CA
At 08:04 AM 7/3/99 -0700, Bonnie wrote:
What I am looking for--and there
>probably isn't such a thing--but an alarm to sound at the time of a
quake
>occurring and then text to appear telling me in plain text where the
quake
>occurred and the epicenter and magnitude of the event.
* John C. and Jan H. Lahr *
* JohnJan@........ *
* 1925 Foothills Road *
* Golden, Colorado 80401-1718 *
* (303) 215-9913 *
* http://lahr.org/john-jan *
* AOL version of homepage: *
* http://lahr.org/john-jan/homepage.html *
* http://giseis.alaska.edu/lahr *
_____________________________________________________________________
Public Seismic Network Mailing List (PSN-L)
Subject: Re: sound picture?
From: "Bonnie Schafer" bschafer@.........
Date: Sat, 3 Jul 1999 21:06:29 -0700
Hi, I have a Pentium 133 running Windows '95 hopefully to be upgraded to '98
and I am using a speech program called Jaws--Job Access With Speech.
Anyway, according to what I have been told Jaws will read Java language and
it can also handle a Dos Window. I am going to try and find out a little
more about this as I will be attending the American Council of the Blind
convention in L.A. The people who wrote Jaws will be there and I will pose
these questions to them. So, as far as I know there shouldn't be a problem
with this. I know that in the earlier versions of Jaws there were some
difficulties reading Java but that has been fixed I am told.
I would love a program like this and can read the Cal Tech reports just
fine. Let me know how much you would want for doing this. It is very much
appreciated. If you have any further questions please feel free to ask me.
Thanks.
Bonnie the crafty crafter
_____________________________________________________________________
Public Seismic Network Mailing List (PSN-L)
Subject: Re: GPS's - GPS Timing System Announcement
From: Larry Cochrane cochrane@..............
Date: Sat, 03 Jul 1999 23:13:57 -0700
Hi Karl,
Good timing for your message. I just finished a web page documenting
the GPS timing system I will be offering. The web page URL is
http://www.seismicnet.com/gps/. There you will find photos and some
documentation on the system, as well as the cost.
The antenna I have is not weather proof and only has 10 feet of cable. I'm
not sure if it can drive 150 feet of cable with having 26 db of gain. One
thing you can do is place the receiver near the antenna and run a long
RS-232 cable. The baud rate between SDR and the GPS receiver is 9600. You
should be able to run a 3 wire shielded cable that long. All you need is
transmit, receive and 1 PPS lines + ground. You will need to power the
receiver using a power supply near it. The unit takes 7 to 40 vdc at a
250ma to power it. Maybe you could run a 4th wire for power. As long as
theres more then 7 volts at 250 ma at the other end, it should power the
unit just fine.
For the interface board I ended up laying out my own board. There were a
few things I didn't like about the TAPR board, and, I thought it would be a
good board too try and layout myself. Being a simple board I thought I
would try out my hand at laying out a PC board. My brother laid out all of
my other boards. I used a program called WinBoard. I'm not very happy with
it. It constantly crashed or locked up but I finally made a board I was
happy with. All in all it turned out pretty good.
So far I have 4 units going to Italy and maybe 6 units to Portugal. I
bought 10 GPS receivers and had 15 blank interface cards made. The problem
is I haven't heard from my contact in Portugal and can't get a PO number
and shipping address. So if I don't here from him in a few days I would
like to sell the receivers I have ASAP since the cost is on my credit card.
-Larry Cochrane
Redwood City, PSN
At 12:21 AM 7/3/99 -0700, you wrote:
>Greetings --
>
>The San Diego Museum of Natural History is interested in buying a GPS for
>timing for their seismometer, which will be running SDR.
>
>The GPS must accomodate an external active antenna that can be located on
>the roof, at then end of about 150 feet of cable. Of course, cost is a
>factor too.
>
>Does anyone have any recommendations on a GPS I could suggest to the museum?
>
>
>Karl Cunningham
>La Mesa, CA.
>PSN Station #40
>karlc@.......
_____________________________________________________________________
Public Seismic Network Mailing List (PSN-L)
Subject: Re: sound picture?
From: The Lahrs JohnJan@........
Date: Sun, 04 Jul 1999 05:42:53 -0600
Hi Bonnie,
You can test if you have java installed by going to a DOS window
and typing the command: java
If it's installed the response will be a number of lines starting
with the line:
Usage: JAVA.EXE [-options] class [args...]
If it's not installed, then the response will be:
Bad command or file name
I could give you a .zip file with java and my small program
files included, but all you would need is the small program
files if you already have java installed on your PC. The .zip
file that includes java is 11.9 MB.
The program I'm working on will wake up every 5 minutes and
check if the Caltech earthquake listing file has been changed. If
it has, then the computer bell will sound every five seconds for
5 minutes. There will be a file on your disk named neweqs.fin
with a listing of the new earthquakes. If you're away from
the computer for more than 5 minutes, you can just check the
file neweqs.fin to see if you've missed an alarm.
How does this sound?
I just noticed one slight problem. Sometimes the Caltech event file
is changed because an earthquake more than 7 days old has been
dropped from the current listing. In this case, the alarm sounds
but the file neweqs.fin contains the oldest event in the new
listing rather than a very recent event.
John
At 09:06 PM 7/3/99 -0700, you wrote:
>Hi, I have a Pentium 133 running Windows '95 hopefully to be upgraded to '98
>and I am using a speech program called Jaws--Job Access With Speech.
>Anyway, according to what I have been told Jaws will read Java language and
>it can also handle a Dos Window.
John C. Lahr
POB 1529
Golden, CO 80402
(303) 215-9913
http://lahr.org/john-jan
I am only one
But still I am one.
I cannot do everything
and because I cannot
do everything
I will not refuse
to do the something
that I can do.
Edward Everette Hale
_____________________________________________________________________
Public Seismic Network Mailing List (PSN-L)
Subject: Computer card
From: Arie Verveer ajbv@............
Date: Sun, 04 Jul 1999 20:33:32 +0800
Hi, I thinking of buying a Y2K card that fits in the ISA slot of my old
486 computer. It sounds quick and easy fix. Has anyone had any
experience with this type of card. All the computer runs is Win95
(networked) and Larry's program SDR.
Arie
See: http://www.mgram.com.au
_____________________________________________________________________
Public Seismic Network Mailing List (PSN-L)
Subject: Seismograph
From: Marchal van Lare vanlare@..............
Date: Sun, 4 Jul 1999 09:25:57 -0400
Hi all,
One year ago I started recording earthquakes with three 4.5 Hz =
Mark Products geophones. These geophones are only sensitive to =
local earthquake activity. =
The problem is, I am missing the large distant earthquakes.
To be able to detect the larger distant events I will need
a long period seismograph.
I tried to build my own device several times, but without good
results.
My question is, do anyone know of any source where I can buy a good
working seismograph or parts? Perhaps someone who is willing to =
build one for me? =
I am looking forward to hear from you.
Best regards,
Marchal van Lare
-Nieuwvliet, The Netherlands
_____________________________________________________________________
Public Seismic Network Mailing List (PSN-L)
Subject: Re: sound picture?
From: "Bonnie Schafer" bschafer@.........
Date: Sun, 4 Jul 1999 06:59:10 -0700
Hi, first of all, I would like to apologize to the list for all of this
but I can't get the address to come up privately when I use the reply to
author command in my email program.
Anyway, I went to a Dos Window and tried it and got the "bad command or file
name." However, I did see a Java folder under Windows and it has some stuff
in it. Should I try and install it from that directory? Sorry, my old Dos
is showing?
Thanks.
By the way, your program sounds like it is just what I am looking for.
Bonnie the crafty crafter
_____________________________________________________________________
Public Seismic Network Mailing List (PSN-L)
Subject: Re: sound picture?
From: The Lahrs JohnJan@........
Date: Sun, 04 Jul 1999 08:30:04 -0600
Bonnie,
Check if you have a file named java.exe in a bin directory beneath
your java directory. That's one of the critical files, among many
others, for running a java program. Also, I forgot to mention,
when you run this program you need to be logged onto the internet,
as it goes out via the internet every 5 minutes to get the latest
listing of events from Caltech. If you find java.exe, let me know
what directory it is in and what the sister directories next to
it are.
I'm not too worried about the noise on the PSN list, as someone
else might also decide to do this and the archive will then include
this discussion.
John
At 06:59 AM 7/4/99 -0700, you wrote:
>I did see a Java folder under Windows and it has some stuff
>in it.
* John C. and Jan H. Lahr *
* JohnJan@........ *
* 1925 Foothills Road *
* Golden, Colorado 80401-1718 *
* (303) 215-9913 *
* http://lahr.org/john-jan *
* AOL version of homepage: *
* http://lahr.org/john-jan/homepage.html *
* http://giseis.alaska.edu/lahr *
_____________________________________________________________________
Public Seismic Network Mailing List (PSN-L)
Subject: Re: Seismograph
From: meredith lamb psnseismograph52@..........
Date: Sun, 04 Jul 1999 10:14:09 -0600
Marchal van Lare wrote:
> Hi all,
>
> One year ago I started recording earthquakes with three 4.5 Hz
> Mark Products geophones. These geophones are only sensitive to
> local earthquake activity.
>
> The problem is, I am missing the large distant earthquakes.
> To be able to detect the larger distant events I will need
> a long period seismograph.
>
> I tried to build my own device several times, but without good
> results.
Marchal,
Scavenger that I am, I am wondering if perhaps, your design/s,
maybe perhaps lacking in success due to perhaps one or two
parts.....usually the pivot or sensor/magnet, if its a horizontal?
Maybe the best approach is to give a description of what you
have now, and any kind of rough measured results....this could
give us a clue perhaps.
Not to be overlooked is potentially the problem of your pier,
what with the likely hood of your soft soils creating problems?
>
>
> My question is, do anyone know of any source where I can buy a good
> working seismograph or parts? Perhaps someone who is willing to
> build one for me?
>
>
Right off the bat, if you can afford the cost, Larry has a variety of
material on his web site. Mechanically, I kind of like the S-G
variety, it doesn't present as much difficulty as say the normal
"garden gate seismometer".
Meredith Lamb
_____________________________________________________________________
Public Seismic Network Mailing List (PSN-L)
Subject: Updated Webpage
From: "Rex Klopfenstein, Jr." rklopfen@.........
Date: Sun, 04 Jul 1999 13:44:23 -0400
I have just posted my siesmograms from the Vancouver and Washington
quakes that occured on the 7/2 and 7/3. I also have posted a
siesmogram
from the quake near Iwo Jima - Bonin Island. I really don't see
anything
except noise in all plots except my high freq N/S. WinQuake picks an
arrival
time of about 5:43 UTC which is close to Bloomington Ind (BLO) site
which is
about 150 miles west of my site. At the pick point I do see a slight
increase
in activity. I don't now if I am seeing noise or an actual event!
--
Rex Klopfenstein, Jr.
Bowling Green, OH
rklopfen@.........
www.wcnet.org/~rklopfen
_____________________________________________________________________
Public Seismic Network Mailing List (PSN-L)
Subject: Re: Seismograph
From: Marchal van Lare vanlare@..............
Date: Sun, 4 Jul 1999 14:52:40 -0400
Hi,
My Lehman looks much like the one described in the Scientific
American article. =
The main frame doesn't consist of pipes, but I used metal bars =
instead. The piano wire is directly attached to the upper main =
frame. I didn't use a turnbuckle.
The boom is a curtain rod of ~ 75 centimeters long. The problem
is, I can't get the boom in a center position. I didn't get much
farther. Perhaps the soft soil I live on (clay and sand) causes =
the boom proble,?
Meredith, you say the SG sensor isn't that much of a problem to
build, even for someone who has problems with the simple 'Lehman'?
:)
Best regards,
Marchal van Lare
-Nieuwvliet, The Netherlands
_____________________________________________________________________
Public Seismic Network Mailing List (PSN-L)
Subject: Re: Seismograph
From: aheerfor@......
Date: Sun, 4 Jul 1999 21:04:30 +0200
>
The piano wire is directly attached to the upper main
frame. I didn't use a turnbuckle.
....
The problem
is, I can't get the boom in a center position. I didn't get much
farther. Perhaps the soft soil I live on (clay and sand) causes
the boom proble,?
<
No, the problem is the attachment of the wire to the upper main frame.
The point of attachment has to be slightly displaced towards the wanted
direction of the boom.
Some kind of screw adjustment of this point is desirable, so that the
period of oscillation around the center position can be adjusted to 20
seconds or similar.
Regards, Anders
_____________________________________________________________________
Public Seismic Network Mailing List (PSN-L)
Subject: Re: Seismograph
From: meredith lamb psnseismograph52@..........
Date: Sun, 04 Jul 1999 13:56:05 -0600
aheerfor@...... wrote:
> >
>
> The piano wire is directly attached to the upper main
> frame. I didn't use a turnbuckle.
> ...
> The problem
> is, I can't get the boom in a center position. I didn't get much
> farther. Perhaps the soft soil I live on (clay and sand) causes
> the boom proble,?
> <
>
> No, the problem is the attachment of the wire to the upper main frame.
> The point of attachment has to be slightly displaced towards the wanted
> direction of the boom.
>
> Some kind of screw adjustment of this point is desirable, so that the
> period of oscillation around the center position can be adjusted to 20
> seconds or similar.
>
> Regards, Anders
>
Marchal and Anders,
The above seems like a way to go. Marchal you could try
drilling the bar through, inserting a bolt and nuts, drill through
the bolt sideways, and reattach the boom wire. A shaft
coupler could work also, but with the added advantage of
being able to slide up or down the metal bar. Of course,
adjusting the rear setscrew/s comes into play for period
adjustments also.
Marschal, if you can center now after repairs, what are you
using for the amplifier, etc.? The curtain rod you use, is
it solid? How much weight in the mass? (I've had problems
with the boom/mass ratio with my S-G's) The key now if
everything works right is your coil and magnet.
Meredith Lamb
_____________________________________________________________________
Public Seismic Network Mailing List (PSN-L)
Subject: Re: Computer card
From: Larry Cochrane cochrane@..............
Date: Mon, 05 Jul 1999 00:26:41 -0700
Arie,
I bought a Y2K board a while back. I finally had some time to play around
with it the other day. It seems to work fine. I tried it on a non Y2K
complaint motherboard running SDR. After plug it in it fixed the date
problem without interfering with SDR. The board I bought is made by
American Megatrends Inc. It cost almost $60.00 USD, a little high for a
very small board that only has 3 ICs on it. The board also has a set of
jumpers to select the BIOS address. I just used the default setting of C800.
-Larry Cochrane
Redwood City, PSN
At 08:33 PM 7/4/99 +0800, you wrote:
>Hi, I thinking of buying a Y2K card that fits in the ISA slot of my old
>486 computer. It sounds quick and easy fix. Has anyone had any
>experience with this type of card. All the computer runs is Win95
>(networked) and Larry's program SDR.
>
>Arie
>
>See: http://www.mgram.com.au
>
>
>
>_____________________________________________________________________
>
>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)
Subject: Re: Seismograph
From: Marchal van Lare vanlare@..............
Date: Mon, 5 Jul 1999 12:02:28 -0400
Hi All,
I think my main frame looks very unstable, so I've decided =
to start 'all over again'.
I'm thinking of making the main frame of one big upright metal =
bar (20-30 centimeters wide), not like the two upright pipes =
from the article. I think this will improve the stability of the =
device.
What do you suggest, a aluminium frame or can any metal be used?
How big should the base plate be?
Any input will be appreciated,
Best regards,
Marchal van Lare
-Nieuwvliet, The Netherlands
_____________________________________________________________________
Public Seismic Network Mailing List (PSN-L)
Subject: Re: Seismograph
From: "Rex Klopfenstein, Jr." rklopfen@.........
Date: Mon, 05 Jul 1999 12:19:08 -0400
You might want to try find some cast aluminum tool plate at a scrap yard.
This material is cast aluminum with both faces ground flat. It is used by
machine tool builders and comes in thickness from about 1/2" and up, there
is also metric thickness. I would check with scrap yards that deal with
machine tool shops and large manufacturers. I used this material for the
base of my S-G Seismometer. It cost me about $20 USD for a piece 3/4" x 6"
x 12", this included having it saw cut to size (I think the sheets are 4' x
8' from mill).
Good Luck
Marchal van Lare wrote:
> Hi All,
>
> I think my main frame looks very unstable, so I've decided
> to start 'all over again'.
>
> I'm thinking of making the main frame of one big upright metal
> bar (20-30 centimeters wide), not like the two upright pipes
> from the article. I think this will improve the stability of the
> device.
>
> What do you suggest, a aluminium frame or can any metal be used?
> How big should the base plate be?
>
> Any input will be appreciated,
>
> Best regards,
>
> Marchal van Lare
> -Nieuwvliet, The Netherlands
>
> _____________________________________________________________________
>
> Public Seismic Network Mailing List (PSN-L)
>
> To leave this list email listserver@.............. with the body of the
> message: leave PSN-L
--
Rex Klopfenstein, Jr.
Bowling Green, OH
rklopfen@.........
www.wcnet.org/~rklopfen
_____________________________________________________________________
Public Seismic Network Mailing List (PSN-L)
Subject: New station on the map
From: Larry Cochrane cochrane@..............
Date: Mon, 05 Jul 1999 14:46:14 -0700
All,
Today I added a new station to the USA station map. Here is Rex
Klopfenstein, Jr. station info:
NAME: Rex Klopfenstein, Jr.
E-MAIL ADDR: rklopfen@.........
HOMEPAGE ADDR: http://www.wcnet.org/~rklopfen
TOWN/CITY: Bowling Green
STATE/PROV: Ohio
COUNTRY: USA
LAT/LONG: 41.367N 83.650W
ELEVATION: 210 meters
STATION CODE: PSBG0
PSBG1 (.hns) S-G Horizontal (North/South) High Frequency Output
PSBG2 (.lns) S-G Horizontal (North/South) Low Frequency Output
PSBG3 (.hew) S-G Horizontal (East/West) High Frequency Output
PSBG4 (.lew) S-G Horizontal (East/West) Low Frequency Output
Uses Larry Cochrane's S-G Board with WWV Time Sync
Recorder: Computer (486/66) running DOS with SDR card
GROUND TYPE: Glacial debris over bedrock. Located in middle of the old
Black Swamp.
-Larry Cochrane
Redwood City, PSN
_____________________________________________________________________
Public Seismic Network Mailing List (PSN-L)
Subject: Re: sound picture?
From: Ted Blank tblank@..........
Date: Mon, 5 Jul 1999 16:29:57 -0700 (PDT)
Bonnie, EMON can be set up to "beep" the PC speaker when it records a
quake. You can specify to beep once, or continuously until you press a
key (that is, a beep every 10 seconds).
Ted Blank
San Jose, California
On Fri, 2 Jul 1999, Bonnie Schafer wrote:
> Hi, was wondering if there is any way I might set up a sound signal that
> would set off some kind of audible alarm when there is a quake occurring? I
> would need to do this as I can't see the charts and seismograms and such. I
> thought of trying to find a seismometer but don't know where to look or how
> to go about making one. Also, would have to find a place to set it up where
> there isn't so much vibration. I live near the freeway and trucks and cars
> are always vibrating the house--funny birds can tell the difference. When
> it is dark and we have a quake I have to get up and calm them down yet when
> a truck or car goes by they don't take notice of them.
>
> Bonnie the crafty crafter
>
>
>
> _____________________________________________________________________
>
> 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)
Subject: Re: Seismograph
From: meredith lamb psnseismograph52@..........
Date: Mon, 05 Jul 1999 21:50:38 -0600
Marchal van Lare wrote:
> Hi All,
>
> I think my main frame looks very unstable, so I've decided
> to start 'all over again'.
>
> I'm thinking of making the main frame of one big upright metal
> bar (20-30 centimeters wide), not like the two upright pipes
> from the article. I think this will improve the stability of the
> device.
Making the mast more massive will help, but it will likely still
need bracing (say two bars running to the side of forward,
allowing space for the boom movement) to prevent the mass
from influencing the tilt.
>
>
> What do you suggest, a aluminium frame or can any metal be used?
> How big should the base plate be?
For the seismometer you have, it should be thick enough to not
bend from mass movement (braces on top or underneath are
a help, if the thickness is like less than 1/2 inch/12.5cm). The
length and width will likely be determined by your wallet. I
don't exactly remember the original design but I think it could
be roughly 1 foot/40cm wide by maybe 2&1/2 foot/90cm
in length.....which is maybe roughly like the Lehman design.
Aluminum is usually preferred over iron for its non-magnetic
propertys and easier to work with. Again, basically whatever
you can find or afford and/or fit into your design. The above
is a rectangular design....but a triangle shape if available might
be even better, especially for stability and the 3 setscrews you
will need. Don't know what you use at the present for setscrews,
but a fine thread makes adjustments quicker for tweaking.
Overall, build it as strong or non-flexible as possible....you will
have less mechanical stress tilt in the long run.
Building a good stable seismometer is not a quick operation.
The only seismometers I ever built are the S-G's I use....but
lacking alot of mechanical metal working equipment, it took
some 4 months to "find" the parts....but with an idea of
longevity and stability.
Aluminum where I live is not cheap ($1.00 a pound scrapyard)
and the larger sizes are kind of rare...but suitable material is
probably out there....one has to call/search for it.
Building a seismometer IS a project for sure....but once you
get it constructed and in operation, it all becomes worthwhile.
Should the project bog down, you might even check area
geophysical equipment outfits, or universitys or seismic stations
for unused older equipment....who knows? The newer and
smaller seismometers are rapidly replacing the older bigger stuff.
Meredith Lamb
_____________________________________________________________________
Public Seismic Network Mailing List (PSN-L)
Subject: Re[2]: Seismograph
From: angel rodriguez angel@............
Date: Tue, 6 Jul 1999 05:06:06 -0400
Hello Marchal,
Monday, July 05, 1999, 12:02:28 PM, you wrote:
MvL> Hi All,
MvL> I think my main frame looks very unstable, so I've decided
MvL> to start 'all over again'.
MvL> I'm thinking of making the main frame of one big upright metal
MvL> bar (20-30 centimeters wide), not like the two upright pipes
MvL> from the article. I think this will improve the stability of the
MvL> device.
MvL> What do you suggest, a aluminium frame or can any metal be used?
MvL> How big should the base plate be?
MvL> Any input will be appreciated,
MvL> Best regards,
MvL> Marchal van Lare
MvL> -Nieuwvliet, The Netherlands
MvL> _____________________________________________________________________
MvL> Public Seismic Network Mailing List (PSN-L)
MvL> To leave this list email listserver@.............. with the body of the
MvL> message: leave PSN-L
Hi,
I have some pictures of my latest lehmann at http://www.barriles.com/gardengate/
Best regards,
angel mailto:angel@............
_____________________________________________________________________
Public Seismic Network Mailing List (PSN-L)
Subject: Re: Seismograph
From: meredith lamb psnseismograph52@..........
Date: Tue, 06 Jul 1999 09:20:02 -0600
angel rodriguez wrote:
> Hello Marchal,
>
> Monday, July 05, 1999, 12:02:28 PM, you wrote:
>
> MvL> Hi All,
>
> MvL> I think my main frame looks very unstable, so I've decided
> MvL> to start 'all over again'.
>
> MvL> I'm thinking of making the main frame of one big upright metal
> MvL> bar (20-30 centimeters wide), not like the two upright pipes
> MvL> from the article. I think this will improve the stability of the
> MvL> device.
>
> MvL> What do you suggest, a aluminium frame or can any metal be used?
> MvL> How big should the base plate be?
>
> MvL> Any input will be appreciated,
>
> MvL> Best regards,
>
> MvL> Marchal van Lare
> MvL> -Nieuwvliet, The Netherlands
>
> MvL> _____________________________________________________________________
>
> MvL> Public Seismic Network Mailing List (PSN-L)
>
> MvL> To leave this list email listserver@.............. with the body of the
> MvL> message: leave PSN-L
>
> Hi,
>
> I have some pictures of my latest lehmann at http://www.barriles.com/gardengate/
>
> Best regards,
> angel mailto:angel@............
>
Hello Angel,
Thanks for the picture reference to your seismometer again.
I like the tension pivot variation you have, but I do have a
question is the BW workmate piece made out of plastic? If
so, is there any sign yet of pressure flow/deformation?
Marschal,
Another variation of the same tension pivot can be seen at:
http://www.users.uswest.net/~psnseismograph52/page22.html
Here, John Lahr used a solid round ring as part of the pivot.
the only major difference between the two is that Angel can
remove the boom and mast, whereas John's pivot is more
involved to remove (but simpler overall, and probably much
stronger). You haven't mentioned the pivot you use, but if it
is like the original Lehman knife edge design, it can present
problems....I'd recommend something like Angels or Johns
pivot design.
Meredith Lamb
_____________________________________________________________________
Public Seismic Network Mailing List (PSN-L)
Subject: Re: Seismograph
From: Marchal van Lare vanlare@..............
Date: Tue, 6 Jul 1999 12:25:42 -0400
Hello Meredith, Angel and others,
Thank you for your recommendations.
Yes, I use the original Lehman knife edge design, since its
quite unstable, I am gonna try to use Angel's version.
Tomorrow I will check a local machine tool store, to find out
if they have some surplus materials.
I am thinking of a 20-30 cm wide frame, to get it as stable as
possible.
I will let you know more tomorrow.
Thank you for your help.
Best regards,
Marchal van Lare
_____________________________________________________________________
Public Seismic Network Mailing List (PSN-L)
Subject: Re: Seismograph
From: robert barns 75612.2635@..............
Date: Tue, 6 Jul 1999 14:59:44 -0400
Marchal,
Try this to get the boom to stay in an equilibrium position (centered):=
Attach a weight to a sewing thread. Use enough weight to make the thre=
ad
hang straight. Hold the thread so that it passes very close (or touching=
)
to the upper attachment point of the wire (which goes to the end of the
boom) and close to the pivot point (at the end of the boom).
Adjust the tilt--this tilt is in the direction which raises or lowers
the end of the boom. Adjust this tilt until the hanging string is about
1/4" away from the lower pivot point in the direction of the far end of t=
he
boom. =
This should allow the boom to come to equilibrium somewhere near center=
.. =
The period of swing (observed without any damping) should be somewhere
around 2 to 8 seconds. This is too short for good Lehman operation--you
should try to get between 16 and 30 seconds. This is done by reducing th=
e
tilt to give less than the 1/4" above. The final distance will be roughl=
y
1/16". =
All this assumes a boom about 24" long. A shorter boom requires
smaller distances.
Soft soil should not be a problem if you have a solid base under the
Lehman--for example, a 3 foot square of plywood at least 1/2" thick.
If your magnet is on the boom, make sure that there is nothing magnetic=
nearby which could be attracted by the magnet. A distance of 3 feet shou=
ld
be safe. =
The base plate of my Lehman is 1/2" thick aluminum and I think that thi=
s
is stiff enough. You can see it on my web site at
www.webspan.net/~bbarns It is made from 1/2" steel piipe just the Sc=
i.
Am. article.
This site also has pictures of Nick Caporossi's Lehman--a neat, lighter=
construction that works well.
=
Bob Barns
_____________________________________________________________________
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Subject: Re: EQ Alarm up and running now.
From: meredith lamb psnseismograph52@..........
Date: Tue, 06 Jul 1999 14:01:05 -0600
Hi all, for those of you at being able to check out John Lahr's
USGS web site in the past few days; its up and running now.
Meredith Lamb
> ********
> The alarm and eq map of NEIS quakes on this page:
>
> http://geohazards.cr.usgs.gov/fingview/fingerview.html
>
> worked to alert me to the new location. If you use
> Netscape it should work right away. With MSIE you will
> need to download a file from the MS page before it will
> work.
>
> John
>
> John C. Lahr
> POB 1529
> Golden, CO 80402
> (303) 215-9913
> http://lahr.org/john-jan
>
> I am only one
> But still I am one.
> I cannot do everything
> and because I cannot
> do everything
> I will not refuse
> to do the something
> that I can do.
> Edward Everette Hale
_____________________________________________________________________
Public Seismic Network Mailing List (PSN-L)
Subject: eq alarm and map pages are down now
From: John Lahr lahr@...................
Date: Tue, 6 Jul 1999 16:35:59 -0600 (MDT)
Hello all,
The Sun computer on which I run the eq alarm and map java code
crashed on the weekend and, although it's up again, is still not
able to run my java code. The principal person who keeps that
computer running is on annual leave, so it may be a while before
the program is working again.
JCLahr
http://geohazards.cr.usgs.gov/fingview/fingerview.html
_____________________________________________________________________
Public Seismic Network Mailing List (PSN-L)
Subject: RE: Seismograph
From: "The Brewers" mbrewer@......
Date: Tue, 6 Jul 1999 22:21:58 -0300
Marchal,
I do not understand why you find the original Lehman knife edge unstable. I
have two Lehman's with vertical knife edges. Both are very stable. I need
to adjust them once every few months. The knife edge supports are small
Exacto knife blades set into the end of the stainless steel threaded boom
rod with 'Marine Tex" epoxy.
What no one ever tells you is that in order to balance the boom assembly you
must attach the suspension point on the boom at the exact point where the
whole thing is in balance when held vertically by its suspension wire. If
the whole boom assembly rests in a horizontal position when you hold it like
a vertical pendulum, then when you attach it to the frame, to act as a
"garden gate", then it will be in perfect balance with respect to the knife
edge trying to move up or down on it's support.
My Lehman's are on Corian counter top material braced along the sides and
near the main support with sections of aluminium sliding door track. When
my first seismometer would not centre, I found that it was because the base
flexed - that was when I added the aluminium stengtheners.
I hope this helps,
Martin
_____________________________________________________________________
Public Seismic Network Mailing List (PSN-L)
Subject: Re: Seismograph
From: barry lotz gbl@.......
Date: Tue, 06 Jul 1999 19:41:13 -0700
Marchal
I have used 3/4" copper water pipe for the support frame.The joints are
mitered and soldered. The geometry isn't to complicated. One triangle in
the horizontal plane at the bottom(vertex at the hinge end) and one
triangle from the top flexture and meeting the lower triangle at the boom
free end , and one single vertical for the rear mast. I believe in
triangles(not to much flexturing). Triangular shapes will result in mostly
axial loads and are stiffer. I like the tension hinge arrangement shown on
Sean Thomas's web site, though I have been successfully using knife edges
with my seismometer for years.
Just a little more input.
Regards
Barry
Marchal van Lare wrote:
> Hello Meredith, Angel and others,
>
> Thank you for your recommendations.
>
> Yes, I use the original Lehman knife edge design, since its
> quite unstable, I am gonna try to use Angel's version.
>
> Tomorrow I will check a local machine tool store, to find out
> if they have some surplus materials.
>
> I am thinking of a 20-30 cm wide frame, to get it as stable as
> possible.
>
> I will let you know more tomorrow.
>
> Thank you for your help.
>
> Best regards,
>
> Marchal van Lare
>
_____________________________________________________________________
Public Seismic Network Mailing List (PSN-L)
Subject: Re: eq alarm and map pages are up again
From: The Lahrs JohnJan@........
Date: Tue, 06 Jul 1999 22:33:44 -0600
I figured out what I was doing wrong and got the earthquake map and alarm
web page working again. Sorry for the recent problems!
John
http://geohazards.cr.usgs.gov/fingview/fingerview.html
John C. Lahr
POB 1529
Golden, CO 80402
(303) 215-9913
http://lahr.org/john-jan
I am only one
But still I am one.
I cannot do everything
and because I cannot
do everything
I will not refuse
to do the something
that I can do.
Edward Everette Hale
_____________________________________________________________________
Public Seismic Network Mailing List (PSN-L)
Subject: Re: sound picture?
From: "Bonnie Schafer" bschafer@.........
Date: Wed, 7 Jul 1999 05:52:05 -0700
Hi Ted,
Thank you for writing.
How woud I go about setting up this "mone"? Thanks
Bonnie the crafty crafter
_____________________________________________________________________
Public Seismic Network Mailing List (PSN-L)
Subject: Re: Seismograph
From: Marchal van Lare vanlare@..............
Date: Wed, 7 Jul 1999 10:49:24 -0400
Hi all,
Here is my update on the progress on my Lehman:
I've been able to get some surplus metal parts, and now I'm
able to build a frame like Nick Caporossi's Lehman as you can
see on www.webspan.net/~bbarns (thanks Bob). The dimensions
will be about the same as in the Scientific American article.
I think I will stick to the knife edge design, but I have a
question about the knife edge, does it have to be sharp to
function? (in other words, the sharper the better? ).
What material can I use other than a curtain rod?
Best regards,
Marchal van Lare
_____________________________________________________________________
Public Seismic Network Mailing List (PSN-L)
Subject: Re: Seismograph
From: S-T Morrissey sean@...........
Date: Wed, 7 Jul 1999 13:34:25 -0500 (CDT)
Marchal,
2 cents worth:
I would strongly recommend that you avoid the knife edge concept for
the boom pivot. The ground motions and/or the required stability for
a useful long period require controlling the fixed end of the boom
in the sub-micron range, which is significantly less than the roughness
of the surfaces of the knife-edge idea. Seismometers have always
used a flat flexure(s) or a taught wire for pivot points: nothing moves
with respect to anything to make micro-positioning noise.
For the boom, I would suggest aluminum channel material, like a U-shape
0.5" high by 0.75" wide (USA dimensions) with a wall thickness of at
least 3/16". Aluminum stock is widely available at most hardware stores.
Even handier would be threaded rod at least 1/2" inch diameter; you can
find brass, aluminum, or stainless steel and matching nuts (at a Tru-Value
store): common steel rod is magnetic and will not work. In fact, the
only place for magnetic material in a seismometer is in the magnet
itself. The large-diameter (I would use 1 1/2" material or larger)
soldered copper tubing frame sounds like a good idea, although again
I would prefer to use large aluminum channel or angle (2" x2" x 1/8" wall)
that are bolted and epoxied at the joints. I would keep in mind that
I want something sturdy enough to stand on without damage, as this
would probably provide long term stability and support for a horizontal
seismometer. The big LP seismometers use aluminum castings 0.5" and up
in thickness, and triangular supports for the boom mast.
Regards,
Sean-Thomas
_____________________________________________________________________
Public Seismic Network Mailing List (PSN-L)
Subject: PSN - Questions (Again)
From: "Rex Klopfenstein, Jr" rklopfen@.........
Date: Thu, 08 Jul 1999 13:31:12 -0400
Sean
Well I have got my two SG units running and they have recorded several
quakes. I now have time to start building a version of your VBB.
I have drawn up a version of your circuit which will have a period of 80
seconds (running) and 1 second (zeroing). I plan to use a 4PDT relay so
that I can switch remotely. I also plan to put the 'zero motor' control
and calibrate pulse trigger in a remote station along with the period
select switch.
I am currently in the process of wiring up the circuits and have come to
a point where I will have to start cutting metal so that I can check out
my VRDT (the easiest way I can figure out to make a test rig!). As soon
as I get my boards wired, I will post the drawings.
I do have several questions on your bridge amplifier/Demod circuit for
the VBB. First, are you using the jumpers near the two 10mF elect and
the 10K pot? Second, are you using the switch near the two 47mF; if so,
what position?
I do also have another question. What are the values of the elect
capacitor (C11-C14) on the Seismic Amplifier circuit that you sent me?
I can guess that these would about 25mF Tant?
Thanks in advance
--
Rex Klopfentein, Jr.
rklopfen@.........
http://www.wcnet.org/~rklopfen
_____________________________________________________________________
Public Seismic Network Mailing List (PSN-L)
Subject: Additional Photos
From: "Rex Klopfenstein, Jr." rklopfen@.........
Date: Thu, 08 Jul 1999 21:38:39 -0400
I finally used up the film in my camera! I have added pictures of my
'seismic vault' and the damping calibration rig I built.
--
Rex Klopfenstein, Jr.
Bowling Green, OH
rklopfen@.........
www.wcnet.org/~rklopfen
_____________________________________________________________________
Public Seismic Network Mailing List (PSN-L)
Subject: Re: Additional Photos
From: meredith lamb psnseismograph52@..........
Date: Thu, 08 Jul 1999 19:58:28 -0600
"Rex Klopfenstein, Jr." wrote:
> I finally used up the film in my camera! I have added pictures of my
> 'seismic vault' and the damping calibration rig I built.
>
Rex,
Thanks for the additional views, its most interesting to see what
others have done or are doing. Appreciate the large sized
photos, its easier to pick up on more items.
The mechanical quality of your instruments is impressive. I
like the milled slots for adjustments you made.
I see you left space in the vault for the STM-8 vertical. That
will be of high interest to see photos on sometime.
Thanks, Meredith Lamb
_____________________________________________________________________
Public Seismic Network Mailing List (PSN-L)
Subject: RE: Seismograph
From: robert barns 75612.2635@..............
Date: Fri, 9 Jul 1999 11:32:28 -0400
Martin,
I disagree with two points you made in your reply to Marchal. 1. I se=
e
no need to balance the boom around the wire attachment point. 2. I thin=
k
that using a knife edge for the boom pivot is asking for complications. =
If
the knife edge is longer than say 1/16", there will be uncertainty as to
the location of the actual point of contact since this will vary as the
boom is positioned up or down from where the knife edge is exactly parall=
el
with its contact surface. I think that using a ball end (say 1/8" dia.) =
or
a disk is easier. I have put a photo of my pivot which uses a disk (abou=
t
1 1/2" in dia.) on my web site. www.webspan.net/~bbarns
The disk simply rests on a flat brass bar. This makes it easy to positio=
n
the contact since it can be anywhere on the bar.
Many hardware stores carry 1/2" dia. aluminum rod. I think that this i=
s
good for the boom.
Bob Barns
_____________________________________________________________________
Public Seismic Network Mailing List (PSN-L)
Subject: Re: Seismograph
From: meredith lamb psnseismograph52@..........
Date: Fri, 09 Jul 1999 11:13:59 -0600
robert barns wrote:
>
> I think that using a ball end (say 1/8" dia.) or
> a disk is easier. I have put a photo of my pivot which uses a disk (about
> 1 1/2" in dia.) on my web site. www.webspan.net/~bbarns
> The disk simply rests on a flat brass bar. This makes it easy to position
> the contact since it can be anywhere on the bar.
> Many hardware stores carry 1/2" dia. aluminum rod. I think that this is
> good for the boom.
> Bob Barns
>
Bob,
Went to your web site and saw the pivot.
Your disk roughly resembles a glass cutter metal disk. I presume
its like a washer put in a drill press collet with a bolt/nut attachment
and filed down as it was spun?
Meredith Lamb
_____________________________________________________________________
Public Seismic Network Mailing List (PSN-L)
Subject: Re: STM-8 CONSTRUCTION
From: S-T Morrissey sean@...........
Date: Fri, 9 Jul 1999 12:51:49 -0500 (CDT)
Jim,
Regarding your questions of June 27:
As I have often said before, I don't think that there is anything
particularly special in the dimensional selections for the STM-9
vertical seis. I suppose I could say that my design is mostly intuitive,
based on many years of experience. Essentially, I started out with
a leaf-spring, added a mass and a boom to connect them, which required
hinges for the boom and flexures for the spring, etc. And it works with
a self noise level and stability much better than I anticipated.
Regarding the square tubes that are part of the spring clamp:
the idea is to apply a firm continuous termination of the stresses
across the end of the spring, rather than just a few screws.
I also thought it would avoid thermally sensitive micro-stresses
that a row of screws would create. It seems to work. If I had a mill,
I would consider milling an 0.018" slit lengthwise through the center
of a 1/4 " brass bar for the ends of the leaf spring; the 0.010 slits
at the ends for the flexures would have to be at a right angle to the
slit for the spring.
I attached the flexures to the brass bars by means of centered slits
in the 3/16" bars for several reasons (compared to soldering them to
the side of the bar): it is much stronger; it dosn't apply any torque
to the bar; it is much more creep resistant, etc.
The slits are easy to do with a 0.010" jewelers saw blade available
at True-Value stores. I use a jig to get it centered and square.
THe brass cuts like butter when making such a fine slit.
When I solder in the bronze flexures, I am careful to apply the heat
(from a small torch) only to the brass bar itself so as not to soften the
temper of the flexures. If the flexure strips DO get heated, I restore
the temper by immediately spraying them with water.
I did some evaluation of the braided stainless fishing leader, but it presents
problems in fastening it to the bars. Feeding it through a small hole in
the bar and crimping a band (from the crimp part of a connector pin) on
the ends seems to work. THen it is epoxied into the hole under tension to
prevent micro-positioning noise. I did not use this flexure in a completed
seis yet, so I don't know how it compares noise-wise to the flat strips.
But I may have to use it to work up an alternative to the "Lehman" design
that uses only taught wires for the boom suspension (using guitar strings.)
Regards,
Sean-Thomas
_____________________________________________________________________
Public Seismic Network Mailing List (PSN-L)
Subject: STM circuit questions
From: S-T Morrissey sean@...........
Date: Fri, 9 Jul 1999 13:57:43 -0500 (CDT)
Rex,
I assume that you realize that the SG design can be configured as
a VBB system using its capacitive displacement detector, or by
replacing the latter with a VRDT.
For the STM-8, you might want to consider having the zero motor
control switch be a 3PDT with the extra pole activating the relay
to switch to the shorter period while zeroing.
Regarding the demodulator schematic: some things are still left over
from the tiltmeter application, but may be useful. Using numbers
from your schematics:
The jumper J1 at R23 and C12,13 is to provide about 10x gain for the
AC bridge amplifier. I have found that this makes the sensitivity too
high to work with for the VRDTs that I make. But there is an additional
10x gain in the DC displacement amplifier that could be omitted if the
demodulator gain is already 10xed. But a VRDT with 2500 mv/micron is
difficult to calibrate, even with a differential micrometer. On the other
hand, if the VRDT gap (between the coils) is large (like 3-5mm) the
added AC gain may be necessary to get a nominal output.
Switch S3 and C16,17 are a low pass filter. I am using 0.47uf, as well
as other values (as low as 0.001), to play with the loop response at
high frequencies vs instabilities.
Also, the VRDT calibration switch S1 and resistors R12,14, 1nd 15 are
optional as far as the seis is concerned. The VBB seis is calibrated
with DC current in the auxilliary calibration coil. The values of the
resistors assume that the VRDT reactance change is 22 ohms / 10*microns,
and are handy for evaluating amplifier gains, etc. The same can be
said for the "zero-test" switch S2 and R16-18: it is very useful for
evaluating the circuit performance, but not used in the normal operation
of the seis. For this reason, these are mounted on the bridge amp board,
rather than being on the control box panel.
Regarding the seismic amplifier, the capacitors C11-14 are for power supply
filtering, and can be any handy value; they are in pairs at opposite
ends of the amp board. Also, the DC-blocking or 60/90 second high-pass
capacitors C17-20 and C21-24 are to remove the amplifier DC offset from
the telemetry VCO (voltage controlled oscillator) input to keep the FM
carriers from wandering around (we had only 90hz of "guard band" between
each channel). The 330uf capacitors are expensive, and they can be
replaced with the jumpers at J1 and J2. Also, the gain switch(es)
can be replaced with selected gain resistors to save money. An overall
gain of 60db (x1000) (S5 + S9) is a handy value, although a max of 90db
(x 32768) (S7 + S10) may be necessary for a small geophone.
Regards,
Sean-Thomas
_____________________________________________________________________
Public Seismic Network Mailing List (PSN-L)
Subject: Farewell Party for Ted Blank & Family, Sunday July 11th
From: Larry Cochrane cochrane@..............
Date: Fri, 09 Jul 1999 14:00:20 -0700
For the N.Cal. PSNers;
Ted Blank and family will be moving away from the area soon. They are
having a farewell party on Sunday. See below for more information.
-Larry Cochrane
Redwood City, PSN
>From: gleisner@..........
>To: cochrane@..............
>Date: Fri, 9 Jul 1999 10:03:28 -0400
>Subject: Farewell Party for Ted Blank & Family, Sunday July 11th
>
>
>
>Larry, Thanks so much for sharing this with the seismology crowd ...
>
>We're leaving San Jose - We'd Like to Say Farewell to YOU!!
>When: Sunday July 11th - open house starting at 2pm
>Where: 954 Foxswallow Ct., San Jose
>RSVP: Acceptances only - 408/323-8415 or 1152 (fax)
>Mementos: We're making a family scrapbook so anything, ie pictures, you
might
> have to help us remember you and the good times in sunny California
>appreciated
>
>Directions: 85 south, exit Almaden X'way. South on Almaden X'way about 4
>miles.
>Turn left on Via Valente light (PW on left) - 2nd right onto Bret Harte.
>After stop sign - 2nd left onto Shearwater - 2nd left onto Foxswallow, 1st
house
>on left.
>
>Our New Address:
>238 Highland Street
>Portsmouth, NH 03801
>603/433-9180
>603/433-9190 (Fax)
>
>
>Regards, Tina Gleisner
>Program Director, eCommerce Architecture & Project Management
>gleisner@........... calendar indicates NY/CA
>NY: 914.784.3256 (8.863); fax x6045
>CA: NY tieline rings in CA or 408.268.4925; fax 408.323.5512
>
>
>
>
_____________________________________________________________________
Public Seismic Network Mailing List (PSN-L)
Subject: Re: Farewell Party for Ted Blank & Family, Sunday July 11th
From: Edward Cranswick cranswick@........
Date: Fri, 09 Jul 1999 15:39:06 -0600
Ted & Family-
It has been a long trip so far for you all around the world -- Wappinger's
Falls, Japan, Moscow (where you met Tanya, my ex-mother-in-law, before I did),
San Jose -- and now Back East again. I am glad I had a chance to visit you at
home in San Jose and do last year's AGU PSN presentation with you and Jan Froom
and all the kids and the teachers. I am sorry to miss your goodbye party. I
wish you well and look forward to records from the old stable craton in Maine.
-Edward
Larry Cochrane wrote:
> For the N.Cal. PSNers;
>
> Ted Blank and family will be moving away from the area soon. They are
> having a farewell party on Sunday. See below for more information.
>
> -Larry Cochrane
> Redwood City, PSN
>
>
> >From: gleisner@..........
> >To: cochrane@..............
> >Date: Fri, 9 Jul 1999 10:03:28 -0400
> >Subject: Farewell Party for Ted Blank & Family, Sunday July 11th
> >
> >
> >
> >Larry, Thanks so much for sharing this with the seismology crowd ...
> >
> >We're leaving San Jose - We'd Like to Say Farewell to YOU!!
> >When: Sunday July 11th - open house starting at 2pm
> >Where: 954 Foxswallow Ct., San Jose
> >RSVP: Acceptances only - 408/323-8415 or 1152 (fax)
> >Mementos: We're making a family scrapbook so anything, ie pictures, you
> might
> > have to help us remember you and the good times in sunny California
> >appreciated
> >
> >Directions: 85 south, exit Almaden X'way. South on Almaden X'way about 4
> >miles.
> >Turn left on Via Valente light (PW on left) - 2nd right onto Bret Harte.
> >After stop sign - 2nd left onto Shearwater - 2nd left onto Foxswallow, 1st
> house
> >on left.
> >
> >Our New Address:
> >238 Highland Street
> >Portsmouth, NH 03801
> >603/433-9180
> >603/433-9190 (Fax)
> >
> >
> >Regards, Tina Gleisner
> >Program Director, eCommerce Architecture & Project Management
> >gleisner@........... calendar indicates NY/CA
> >NY: 914.784.3256 (8.863); fax x6045
> >CA: NY tieline rings in CA or 408.268.4925; fax 408.323.5512
> >
> >
> >
> >
>
> _____________________________________________________________________
>
> 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)
Subject: North East USA?
From: Nick & Sophie Caporossi nickcap@.............
Date: Sat, 10 Jul 1999 17:37:56 -0400
To PSN group:
The ldgo.columbia.edu at:
>http://quake.wr.usgs.gov/cgi-bin/finger?quake@................. > had been
listing quakes and other seismic activity on the East Coast of the USA. It
had been covering an area from Maine to Virginia and parts of Ontario
Canada. It is no longer doing so. Does any one know of another site that
has the same information?
On the subject of seismic activity, it would be informative if there was
some discussion on what we are seeing when the sensor detects an event.
Since I am novice in the field of seismology, I have a few of questions.
1: In some Earthquakes, why is it that the "P" and "S" waves do not arrive
at the time where I would expect them to?
2: In some quakes, the Event starts with a large Spike and then gradually
decreases. Why?
3: Why do some quakes gradually swell. They look like a rubber garden hose
that is on the verge of blowing up. The 6.3 in the Solomon Islands on
7/9/99 made that kind of an unusual foot print.
Nick
_____________________________________________________________________
Public Seismic Network Mailing List (PSN-L)
Subject: Re: North East USA?
From: Greg ghost@.............
Date: Sat, 10 Jul 1999 22:33:53 -0700
Nick & Sophie Caporossi wrote:
>
> To PSN group:
> The ldgo.columbia.edu at:
> >http://quake.wr.usgs.gov/cgi-bin/finger?quake@.................
The finger server is not responding directly. I thought it might have
been a broken cgi script, but it wasn't. You're best bet is to write to
root@................. or maybe administrator@................. or maybe
postmaster. It might be under attack or taken down by accident. Finger
servers provide a lot information for crackers (bad hackers) and sys
admins take them down to limit that.
> Canada. It is no longer doing so. Does any one know of another site that
> has the same information?
There might be a ftp server or mailing list with the exact same info.
The sys admin (root) would know for sure.
> 1: In some Earthquakes, why is it that the "P" and "S" waves do not arrive
> at the time where I would expect them to?
I'll skip that one for someone else to wrestle with.
> 2: In some quakes, the Event starts with a large Spike and then gradually
> decreases. Why?
>
> 3: Why do some quakes gradually swell. They look like a rubber garden hose
> that is on the verge of blowing up. The 6.3 in the Solomon Islands on
> 7/9/99 made that kind of an unusual foot print.
I try to imagine the plates actual contact and movement. Is is hard rock
snapping? Or maybe more like a landslide giving way.
Good luck with that finger info,
Greg
_____________________________________________________________________
Public Seismic Network Mailing List (PSN-L)
Subject: Moderate Quake
From: Wayne Abraham J73WA abrahamw@........
Date: Sun, 11 Jul 1999 08:43:51 -0400
A moderate earthquake was recorded and felt here on Dominica around
07:58 today. USGS does not have it listed. The badly clipped .bbl file
has been added to Larry's archive. DM1, 2 and 3 files will be submitted
later today.
--
Wayne Abraham
1430 Rodney Street
Portsmouth, Dominica
abrahamw@........
http://www.freeyellow.com/members6/dominicapsn/
_____________________________________________________________________
Public Seismic Network Mailing List (PSN-L)
Subject: Re: North East USA?
From: bc bruce@.......
Date: Sun, 11 Jul 1999 09:32:39 -0400
I'm not sure if they publish current activity but you might check the
Weston observatory at Boston College
http://www.bc.edu/bc_org/avp/cas/wesobs/default.html
Bruce
At 05:37 PM 07/10/1999 -0400, you wrote:
>To PSN group:
> The ldgo.columbia.edu at:
>>http://quake.wr.usgs.gov/cgi-bin/finger?quake@................. > had been
>listing quakes and other seismic activity on the East Coast of the USA. It
>had been covering an area from Maine to Virginia and parts of Ontario
>Canada. It is no longer doing so. Does any one know of another site that
>has the same information?
>
> On the subject of seismic activity, it would be informative if there was
>some discussion on what we are seeing when the sensor detects an event.
>Since I am novice in the field of seismology, I have a few of questions.
>
>1: In some Earthquakes, why is it that the "P" and "S" waves do not arrive
>at the time where I would expect them to?
>
>2: In some quakes, the Event starts with a large Spike and then gradually
>decreases. Why?
>
>3: Why do some quakes gradually swell. They look like a rubber garden hose
>that is on the verge of blowing up. The 6.3 in the Solomon Islands on
>7/9/99 made that kind of an unusual foot print.
>
>Nick
>
>_____________________________________________________________________
>
>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)
Subject: Quake peaking monitor now
From: meredith lamb psnseismograph52@..........
Date: Sun, 11 Jul 1999 08:32:47 -0600
Quake coming in starting about 14:21 utc....fairly strong with
monitor overscales. Still fairly strong at 14:33.
Meredith Lamb
_____________________________________________________________________
Public Seismic Network Mailing List (PSN-L)
Subject: BIG QUAKE ON AIR NOW
From: "Giovanni Rotta" rottag@..........
Date: Sun, 11 Jul 1999 16:43:33 +0200
Italian stations are recording a large quake (M. 6.1) 16:26 UTC
Giovanni Rotta
Via F. Pizzigoni, 10
33010 Resia (Udine) I
Lat. 46.373 N Long. 13.305 E
rottag@..........
Italian stations are recording a large quake (M. =
6.1)=20
16:26 UTC
Giovanni Rotta
Via F. Pizzigoni, 10
33010 =
Resia=20
(Udine) I
Lat. 46.373 N Long. 13.305 E
rottag@..........
Subject: Sesmicity Viewer and audio Earthquake Alarm
From: meredith lamb psnseismograph52@..........
Date: Sun, 11 Jul 1999 09:16:47 -0600
Tried John Lahr's USGS web site:
http://geohazards.cr.usgs.gov/fingview/fingerview.html
for this central america quake.
The Seismicity Viewer is still slow loading (probably because
of this quake computer overload).
The Earthquake Alarm shows "Not Found", but, the audio
signal came through regardless about 15:01 utc. It sounds
like a finch here.
Meredith Lamb
--
Main Web site: http://www.users.uswest.net/~psnseismograph52/Index.html
and....
http://members.xoom.com/seismogram/Index.html
a mirror site.
_____________________________________________________________________
Public Seismic Network Mailing List (PSN-L)
Subject: Re: Quake peaking monitor now
From: barry lotz gbl@.......
Date: Sun, 11 Jul 1999 08:39:26 -0700
Meredith
I was awaken by SDR singing. I realized that only the Lehman was acting
up. After exorcizing a small spider I went back to bed. About 1 minute
later it began again. What's with this spider? Opps, all the sensors were
active now. This wasn't a false alarm.
Barry
meredith lamb wrote:
> Quake coming in starting about 14:21 utc....fairly strong with
> monitor overscales. Still fairly strong at 14:33.
>
> Meredith Lamb
>
_____________________________________________________________________
Public Seismic Network Mailing List (PSN-L)
Subject: Re: Quake peaking monitor now
From: meredith lamb psnseismograph52@..........
Date: Sun, 11 Jul 1999 09:50:11 -0600
barry lotz wrote:
> Meredith
> I was awaken by SDR singing. I realized that only the Lehman was acting
> up. After exorcizing a small spider I went back to bed. About 1 minute
> later it began again. What's with this spider? Opps, all the sensors were
> active now. This wasn't a false alarm.
> Barry
>
> meredith lamb wrote:
>
> > Quake coming in starting about 14:21 utc....fairly strong with
> > monitor overscales. Still fairly strong at 14:33.
> >
> > Meredith Lamb
> >
SPIDERS AND FINCH BIRD SIGNALS.....HA.
Hi Barry,
This seems like a weekend deal anymore....a quake to wake
up the morning oversleepers. Am monitoring the earthquake
alarm site, for the finch bird "alarm". When I first tried it, the
sound kind of startled me, till I realized that was the signal....
I like it....ha.
Still getting low level long period stuff....maybe 9 seconds
from the quake, and, still recording. Note alot of stations
around the world clipped. Red Puma max mag shows a
preliminary of around 6.1, but, I have a feeling it may
eventually be assigned a larger magnitude. The Vancouver
area quakes weren't near as large if I remember vaguely
right.
Meredith Lamb
_____________________________________________________________________
Public Seismic Network Mailing List (PSN-L)
Subject: Re: Quake peaking monitor now
From: DGentry509@.......
Date: Sun, 11 Jul 1999 12:23:21 EDT
Hondurus 1414:15 15.70N 88.26W 10.0 6.6Ms A
finger 2 quake via matt drudge home page
_____________________________________________________________________
Public Seismic Network Mailing List (PSN-L)
Subject: Re: Quake peaking monitor now
From: barry lotz gbl@.......
Date: Sun, 11 Jul 1999 09:30:23 -0700
Meredith
I agree, I see the new event in the higher 6's. I saved some data from
Brazil BDFB station via autodrum. It's great to get data from elsewhere in the
world (in near real time) and be able to incorporate it with ones station in
Winquake with the location map.
Barry
_____________________________________________________________________
Public Seismic Network Mailing List (PSN-L)
Subject: Fwd: Quake Shakes Guatemala, Honduras
From: Seisguy@.......
Date: Sun, 11 Jul 1999 12:26:38 EDT
Quake Shakes Guatemala, Honduras
..c The Associated Press
GUATEMALA CITY (AP) - A strong earthquake shook the Caribbean coast of
Guatemala and Honduras on Sunday, damaging some buildings. There were no
immediate reports of injuries.
The U.S. Geological Survey in Golden, Colo., reported the quake's magnitude
at 6.6 while Guatemala's Seismological Station estimated the force at 5.9.
The preliminary center point was located about 20 miles east of the
Guatemalan coastal city of Puerto Barrios, according to Jim Taggart, a
geophysicist with the survey's National Earthquake Information Center.
The quake occurred at 8:14 a.m. local time (10:14 a.m. EDT), provoking alarm
among people across Guatemala.
It damaged buildings in eastern Guatemala, including the Our Lady of the
Trinity church in Chiquimula, 90 miles southwest of Puerto Barrios.
Guatemala's disaster-relief agency CONRED was surveying the rest of the
nation for reports of damage or injuries.
The quake was felt in the Honduran capital of Tegucigalpa, 150 miles
southeast of Puerto Barrios, and in the Mexican city of Villahermosa, 330
miles to the northwest. It also was felt in El Salvador and Belize.
AP-NY-07-11-99 1225EDT
Copyright 1999 The Associated Press. The information contained in the AP
news report may not be published, broadcast, rewritten or otherwise
distributed without prior written authority of The Associated Press.
To edit your profile, go to keyword NewsProfiles
.
For all of today's news, go to keyword News.
Subject: Fwd: Quake Shakes Guatemala, Honduras
From: Seisguy@.......
Date: Sun, 11 Jul 1999 12:27:56 EDT
Quake Shakes Guatemala, Honduras
..c The Associated Press
GUATEMALA CITY (AP) - A strong earthquake shook the Caribbean coast of
Guatemala and Honduras on Sunday, damaging some buildings. There were no
immediate reports of injuries.
The U.S. Geological Survey in Golden, Colo., reported the quake's magnitude
at 6.6 while Guatemala's Seismological Station estimated the force at 5.9.
The preliminary center point was located about 20 miles east of the
Guatemalan coastal city of Puerto Barrios, according to Jim Taggart, a
geophysicist with the survey's National Earthquake Information Center.
The quake occurred at 8:14 a.m. local time (10:14 a.m. EDT), provoking alarm
among people across Guatemala.
It damaged buildings in eastern Guatemala, including the Our Lady of the
Trinity church in Chiquimula, 90 miles southwest of Puerto Barrios.
Guatemala's disaster-relief agency CONRED was surveying the rest of the
nation for reports of damage or injuries.
The quake was felt in the Honduran capital of Tegucigalpa, 150 miles
southeast of Puerto Barrios, and in the Mexican city of Villahermosa, 330
miles to the northwest. It also was felt in El Salvador and Belize.
AP-NY-07-11-99 1225EDT
Copyright 1999 The Associated Press. The information contained in the AP
news report may not be published, broadcast, rewritten or otherwise
distributed without prior written authority of The Associated Press.
To edit your profile, go to keyword NewsProfiles
.
For all of today's news, go to keyword News.
Subject: Re: Seismograph
From: robert barns 75612.2635@..............
Date: Sun, 11 Jul 1999 13:56:26 -0400
Meredith,
Good deduction! The disk was a washer I found in my junk box.
Bob Barns
_____________________________________________________________________
Public Seismic Network Mailing List (PSN-L)
Subject: Re: North East USA?
From: John Hernlund hernlund@.......
Date: Sun, 11 Jul 1999 12:21:21 -0700 (MST)
On Sat, 10 Jul 1999, Nick & Sophie Caporossi wrote:
> listing quakes and other seismic activity on the East Coast of the USA. It
> had been covering an area from Maine to Virginia and parts of Ontario
> Canada. It is no longer doing so. Does any one know of another site that
> has the same information?
There is a good global catalog hosted by Berkeley's seismo lab web site.
All you do is input the min/max latitude and longitude and the beginning and
end time and a few other parameters and the computer will build a list of all
quakes in that area. I am not sure how often it is updated, but it seems
fairly thorough. I don't remember the address, but you can find it by
clicking through www.berkeley.edu to their site.
> On the subject of seismic activity, it would be informative if there was
> some discussion on what we are seeing when the sensor detects an event.
> Since I am novice in the field of seismology, I have a few of questions.
>
> 1: In some Earthquakes, why is it that the "P" and "S" waves do not arrive
> at the time where I would expect them to?
The way that "expected" travel times are found is only by reference to a
large compilation of seismograms for various epicentral distances. The
arrivals are averaged and formed into one of the standard earth models (like
IASPEI, PREM, J-B, etc.). However, since this averaging is done over the
whole globe regardless of location, the result is that differences in velocity
caused by anomalies in various locations are not resolved. When the ray path
for the waves between a quake and source encounter one of these so-called
"lateral heterogeneities" the expected travel time differs from the real
travel time. Newer techniques have been used for quite some time now that use
knowledge of the wave ray path and the difference in real travel time and
expected travel time from a model to make a map of these irregularities based
on changes in their seismic velocities. This is usually called "tomography,"
a word which is borrowed from medical techniques that use X-rays and other
sources. Tomography is a fairly simple technique that uses a matrix inversion
to solve for the velocity map of the medium, but it produces pretty pictures
of the interior that everyone loves to look at and attempt an interpretation.
Lateral heterogeneities are probably always caused by changes in chemistry
or temperature in the Earth's interior that are in turn caused by large scale
churning in the mantle. The reason this churning or convection occurs is
because the core releases heat into the mantle, which is a relatively poor
conductor of heat. Hence heat pools up in spots, making the mantle material
expand and become more buoyant. This causes the mantle to deform and move to
accomodate the transfer of heat. Another important lateral heterogeneity
occurs because some portions of the Earth's crust are much thicker than
others. For instance, the ocean crust is usually half as thick as continental
crust...
> 2: In some quakes, the Event starts with a large Spike and then gradually
> decreases. Why?
> 3: Why do some quakes gradually swell. They look like a rubber garden hose
> that is on the verge of blowing up. The 6.3 in the Solomon Islands on
> 7/9/99 made that kind of an unusual foot print.
Both these questions are related. There are many possibilities:
1) Source: The simplest answer to your question is that faults move at
different rates and usually in a very jumpy manner. The first P-arrival is
usually very good to use to identify the behavior of the fault motion that
created the quake. Also, faults are not point sources, but lie along a plane.
Deep earthquakes will also look different. Also, depending on how your
station is oriented with respect to the fault plane will change the manner of
waves coming toward you.
2) Medium: The second way the shape of the first arrival can be changed is by
the material the waves pass through. Small differences can be smoothed out in
the Earth when the waves pass through regions with variations in seismic
velocities. Imagine a bunch of pin balls being dropped into a large pin ball
machine with many bumpers and obstacles. No matter how you arrange their
pattern when starting the drop, they will bounce around and come out more
randomly at the bottom than at the top. This randomness is a smoothed version
of the original pattern.
3) Instrument: Your recording instrument will also impose a change in shape of
the wave arrivals because of its characteristics as a pendulum. The
seismogram is the "convolution" of the real wave form and your instrument's
"impulse response function." The impulse response is the way your seismometer
responds to a sharp input spike. A convolution can be found analytically by
taking the product of the LaPlace or Fourier Transforms for each function and
then inverting back to the time domain. It can also be found numerically (in
the case of digital data) by summing the two records a(i) and b(j) as
SUM[a(i)*b(i-j)]. If a(i) is the real wave form and b(j) is the impulse
response you can see that a response of b(j) = 1,0,0,0,0,0,... is that of a
seismometer that imposes no change in the wave form and most accurately
represents the ground motion. The above sum returns the exact copy of a(i).
However such an impulse response is not physically possible for any real
seismometer. Because of this fact, the seismogram will always be more
broadened than the real wave form. The amount of broadening depends on your
specific instrument. A broadband instrument will partially correct for this
effect for some frequency range by using feedback electronics.
John Hernlund
E-mail: hernlund@.......
WWW: http://www.public.asu.edu/~hernlund/
******************************************************************************
_____________________________________________________________________
Public Seismic Network Mailing List (PSN-L)
Subject: Fwd: 37 Hurt in Central American Quake
From: Seisguy@.......
Date: Sun, 11 Jul 1999 19:05:54 EDT
37 Hurt in Central American Quake
..c The Associated Press
By ALFONSO ANZUETO
GUATEMALA CITY (AP) - A strong earthquake shook the Caribbean coast of
Guatemala and Honduras on Sunday, injuring dozens of people and damaging a
U.S. military base as windows shattered and walls cracked across the region.
At least 37 people were reported injured, many with broken bones, in the
eastern Guatemalan province of Izabal, Vice Gov. Adolfo Hernandez said.
The U.S. Geological Survey in Golden, Colo., reported the quake's magnitude
at 6.6, while Guatemala's Seismological Station estimated the magnitude at
6.1, up from an initial report of 5.9.
The quake, which occurred at 8:14 a.m. local time (10:14 a.m. EDT), provoked
alarm among people across Guatemala, Belize, Honduras and El Salvador.
The preliminary center point was located about 20 miles east of the
Guatemalan coast city of Puerto Barrios, according to Jim Taggart, a
geophysicist with the survey's National Earthquake Information Center.
Roads buckled and buildings cracked at a temporary U.S. military base in
Puerto Barrios, said Lt. Col. Jeff Keane, a U.S. Army reservist who was
across the border in Honduras at the Soto Cano Air Base, where he is based,
when the quake struck.
``We were in a building. The building started shaking and telephone poles
began tilting as the ground trembled. It lasted over a minute,'' Keane told
The Associated Press by telephone from Honduras.
About 200 U.S. Army reservists from Massachusetts and Connecticut are
stationed in Puerto Barrios to help build schools and repair infrastructure
damaged last year in Hurricane Mitch, Keane said. But the schools they are
building appeared not to be damaged, he said.
There were no reports of injuries at either base in Guatemala or Honduras.
But aftershocks continued Sunday in Puerto Barrios.
The earthquake damaged buildings in eastern Guatemala, including the Our Lady
of the Trinity church in Chiquimula, 90 miles southwest of Puerto Barrios.
Windows shattered at the international airport at Santa Elena and the
Guatemalan Air Force base, both in the northern province of Peten.
The quake also cut power to towns in Guatemala's northern and eastern regions.
Guatemala's disaster-relief agency, CONRED, was surveying the rest of the
nation for any further damage or injuries.
In Honduras, the quake caused minor damage, such as cracked walls at a
hospital in the northern city of El Progresso and fallen electrical poles
along the north coast.
``The quake alarmed Hondurans but did not cause deaths or injuries ... only
fear,'' said Jose Zelaya, a Red Cross spokesman in Tegucigalpa, the Honduran
capital.
Seismologists in El Salvador said the quake lasted one minute 10 seconds and
was felt across their country. The Red Cross in El Salvador told local radio
there were no reports of damage or injuries.
The quake was felt as far away as the Mexican city of Villahermosa, 330 miles
northwest of Puerto Barrios.
AP-NY-07-11-99 1842EDT
Copyright 1999 The Associated Press. The information contained in the AP
news report may not be published, broadcast, rewritten or otherwise
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Subject: SEISMO VIEWER
From: "Francesco" franuc@......
Date: Mon, 12 Jul 1999 12:00:39 +0200
Hi all.
It's on line the Northern Italy seismic sequence with Seismogram Viewer
java-program at the usual web address
http://space.tin.it/scienza/frnucer/sve.html (available from our home-page
also).
You should be able to run the Seismogram Viewer on any type of computer with
internet access and a recent web browser that supports Java 1.0 or higher
(i.e. Netscape 3 or higher, Internet Explorer 4 or higher).
I.E.S.N.
Francesco
_____________________________________________________________________
Public Seismic Network Mailing List (PSN-L)
Subject: Re: Computer card
From: Arie Verveer ajbv@............
Date: Mon, 12 Jul 1999 20:20:01 +0800
Hi, The Y2K board woks fine. A recommendation; though as Larry
stated the price is a little high. $60.0 (US), $129 (Australian).
I just gave "SDR" a birthday, Y2K board, 1 gig hard disk and a
network card.
Arie
Larry Cochrane wrote:
>
>
> I bought a Y2K board a while back. I finally had some time to play around
> with it the other day. It seems to work fine. I tried it on a non Y2K
> complaint motherboard running SDR. After plug it in it fixed the date
> problem without interfering with SDR. The board I bought is made by
> American Megatrends Inc. It cost almost $60.00 USD, a little high for a
> very small board that only has 3 ICs on it. The board also has a set of
> jumpers to select the BIOS address. I just used the default setting of C800.
>
> -Larry Cochrane
> Redwood City, PSN
>
> At 08:33 PM 7/4/99 +0800, you wrote:
> >Hi, I thinking of buying a Y2K card that fits in the ISA slot of my old
> >486 computer. It sounds quick and easy fix. Has anyone had any
> >experience with this type of card. All the computer runs is Win95
> >(networked) and Larry's program SDR.
> >
_____________________________________________________________________
Public Seismic Network Mailing List (PSN-L)
Subject: More on Quakes
From: Nick & Sophie Caporossi nickcap@.............
Date: Mon, 12 Jul 1999 14:15:09 -0400
Hi:
Thanks to all that responded to my questions on earthquakes. The suggested
sites for listing of small and large motions of events in the North East of
USA were a help.
The responses that I received were quite informative.
A special thanks to John Hernlund and Greg (don't know your last name).
The recent Quake in Honduras was a classic. The "P" an "S" waves were right
to the second. The "lq" wave fell right on the largest spike. It wiggled
the basement floor for over an hour. Does that mean that the entire earth
was moving for an hour?
Again thanks
Nick
_____________________________________________________________________
Public Seismic Network Mailing List (PSN-L)
Subject: Re: More on Quakes
From: John Hernlund hernlund@.......
Date: Mon, 12 Jul 1999 11:57:26 -0700 (MST)
On Mon, 12 Jul 1999, Nick & Sophie Caporossi wrote:
> The recent Quake in Honduras was a classic. The "P" an "S" waves were right
> to the second. The "lq" wave fell right on the largest spike. It wiggled
> the basement floor for over an hour. Does that mean that the entire earth
> was moving for an hour?
The Earth was dancing a jig for quite a wihle I imagine. One thing to note
about surface waves (lq, lr) is that they have a stronger variation in
velocity than body waves (p, s, etc). This is because their velocity
depends on the material in the uppermost reaches of the earth which is a
lot more heterogeneous that the material in the lower mantle. Also, surface
waves separate out into a continuous wave train because their velocities
depend on their frequency (or period). This is because longer period waves
oscillate deeper in the earth than shorter period surface waves, and this
causes their velocities to depend on different materials. So if you get an
original surface disturbance in the frequency range from 1-40 seconds then
these waves will fan out from the source at different rates (called a group
velocity). A standard reference period for surface waves is usually around 15
seconds because many seismometers respond well in this band. So I guess the
lesson here is not to rely too much on the lq or lr arrivals being just
right, because they probably will be off. An interesting thing to try is to
take a good record with surface waves in it and do small, sharp (many poles)
band pass filters for various periods from 10 to 40 seconds (0.1 to 0.025 Hz)
and see how they appear different. Keep in mind that your instrument will
also influence the results...
John Hernlund
E-mail: hernlund@.......
WWW: http://www.public.asu.edu/~hernlund/
******************************************************************************
_____________________________________________________________________
Public Seismic Network Mailing List (PSN-L)
Subject: Re: Mammoth Lakes 3.8
From: Edward Cranswick cranswick@........
Date: Mon, 12 Jul 1999 22:34:10 -0600
Barry-
I belatedly want to thank you for sending me these. I finally looked at them and was
impressed from the spectra by what a truly low-frequency response they have. Again,
teleseismology is not my forte' but it really looks like you guys are really getting down
there!
-Edward
barry lotz wrote:
> Hi Ed
> They're small files (I try to save only 2X max FFT freq component). Please
> understand, the sensors are an ever evolving process :) "AZ" are the ~20" sensor, and
> "BZ" are the 12" sensor. In the 12" sensor I use a portion of a 16' measuring tape
> return spring instead of the taping blade.
>
> Barry
>
> Edward Cranswick wrote:
>
> > Barry-
> > Thank you. I look forward to seeing your records.
> > -Edward
> >
>
> ------------------------------------------------------------------------
> Name: 980816bz.bl
> 980816bz.bl Type: unspecified type (application/octet-stream)
> Encoding: base64
>
> Name: 980823az.bl
> 980823az.bl Type: unspecified type (application/octet-stream)
> Encoding: base64
>
> Name: 980830az.bl
> 980830az.bl Type: unspecified type (application/octet-stream)
> Encoding: base64
>
> Name: 980903az.bl
> 980903az.bl Type: unspecified type (application/octet-stream)
> Encoding: base64
>
> Name: 980914az.bl
> 980914az.bl Type: unspecified type (application/octet-stream)
> Encoding: base64
>
> Name: 981109az.bl
> 981109az.bl Type: unspecified type (application/octet-stream)
> Encoding: base64
>
> Name: 981207bz.bl
> 981207bz.bl Type: unspecified type (application/octet-stream)
> Encoding: base64
>
> Name: 990128az.bl
> 990128az.bl 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)
Subject: ted blank i need ur postal address
From: "dave nelson" davenelson39@...........
Date: Tue, 13 Jul 1999 01:40:34 PDT
Ted,
please e-mail me ur postal addy. that book u loaned me is in LA
ready to be posted back to u by UPS.
Im now back in new zealand
cheers
Dave Nelson
_______________________________________________________________
Get Free Email and Do More On The Web. Visit http://www.msn.com
_____________________________________________________________________
Public Seismic Network Mailing List (PSN-L)
Subject: Commercial Data Acquisition System
From: John Lahr lahr@...................
Date: Tue, 13 Jul 1999 09:15:20 -0600 (MDT)
Here's a description of a fancy PC seismic data acquisition system, if
you want to record many channels of data or a small network:
JCLahr
**********************
Dear Seismologist:
In July, 1999 PC Systems is releasing ViSeis V2.45 the leading economical=
=20
solution for small and medium-size seismic networks:
a.. Lowest cost. A turnkey ViSeis system (P2-350 PC, GPS, 24-bit A-D,=
=20
software loaded) $3250. OEM is $1450 (you supply the PC and timing).=20
b.. GPS support. GPS is transparently integrated into the system provid=
ing=20
time stamped data.=20
c.. Multitasking. ViSeis tasks operate under Win98/95 allowing networki=
ng,=20
FTP or remote control without interrupting the data acquisition.=20
d.. User interface. ViSeis is controlled via an intuitive graphical use=
r=20
interface (see above).=20
e.. Flexibility. Up to 22-bits of dynamic range and 64 channels.=20
f.. Real technical support. ViSeis is supported by an experienced team =
of=20
software and hardware engineers=20
g.. Standards. ViSeis it built using Labview, the world=92s most popula=
r data=20
acquisition language.=20
h.. Extensibility ViSeis is modular allowing addition of new functional=
ity=20
and hardware.
For more information please contact:
PC Systems Design
Palo Alto, CA | Bozema