PSN-L Email List Message

Subject: Re: WinQuake Times
From: "Geoffrey" gmvoeth@...........
Date: Tue, 10 Nov 2009 09:22:44 -0700

Your Setup is the very kind I like to see.

I once made a torsion seismometer using
a spring made out of an aluminum antenna
rod split down the middle and fastened
at both ends in clamps like the scientists use.
Then it had a long lever arm of wood with a
magnet on the end. It was a hopeful dream
that never realized itself due to annoying
torments in my life. The period must have
been longer than a second. I have faith (chuckle)
in torsional kind of seismic devices.
If you made two and put them back to back
you may possibly cancel out tilt and only
look at vertical motions. But not exactly sure.
Thanks for the input Mr. Sparks,

When I say a science clamp what you do is
drill a hole in a piece of wood then
cut the hole in half or only one side
then you use a screw to clamp whatever in the hole.
The cut area will take away just enough material
to make a proper kind of clamp. I see these
kind of clamps almost everywhere the engineers
are building various things. You may see
a similar thing in an automobile engine
holding down the camshaft.

I very much like your design and would
like to know what you are using for
the folded leaf springs. Your design
requires no frictional boundaries.
Like rolling or pivoting.

Also, are you located on or close to bedrock.

Is your device located outside some distance
from human activity ?

Have you ever considered using two
identical sensors placed pointing
in opposite directions to cancel out
tilt ?

Does your device require periodic adjustments ?

What electronics are you using ?

What program to take your data ?

Thanks ahead of time for any responses.
I make no apologies for my stupid questions,
its the only way to learn in the absence of
expensive books.

I was a resident of Washington state while
attached to the uss Bainbridge cgn25 stationed
in Bremerton Washington. I will not pay taxes to
any state I do not work in so I become a resident of
any state I happen to work in.
I guess Washington can have some of the biggest
earthquakes in the world because it is close
to a subduction boundary near the straights
of Juan De Fuca.

As an adult, I have been a resident of every state in which I ever worked.
Maybe 5.

I got stuck in Arizona or otherwise id be closer
to high tech civilization, and not this electro-mechanical farmer,
cowboy world of Arizona. Apache junction is the elephant
graveyard of the white man. Like in those old Tarzan movies
where all the elephants go to die. Except instead of elephants
it is basically all white human kind of elephants.
I cant say much nice about this place since it represents
to me little more than a low security prison in which I happen
to be an inmate. Seismic watching is a proper sport to escape
the irritations of this dying elephant social world.

Best Regards,

----- Original Message ----- 
From: "RSparks" 
Sent: Tuesday, November 10, 2009 7:56 AM
Subject: WinQuake Times

> Good Morning Geoff,
> I don't quite know how to react to your posting because I am not working 
> much in the area of quake timing.  However, from the posting, I can see 
> that you are watching my PSN quake reports so I need to tell you more 
> about my equipment.
> First, my timing is not very exact.  I installed a ClockCard into my 
> computer, which is controlled by the software ClockWatch.  I think I am 
> accurate to within one second but I recognize that is very poor accuracy 
> for seismic work.
> I am using a tweaked copy of Amaseis to record the events.  Amaseis uses 
> the PC time to change hours and each event is expected to be regularly 
> spaced after that.  Since my sample rate is about 10.3 samples per 
> second, the chance of which hour the last/first sample fell into becomes 
> a probability exercise.  I have never investigated the accuracy of the 
> clock in the A/D device but it is pretty good so the samples should be 
> well spaced.
> I am using an earlier Saum A/D device that I modified slightly to have a 
> wider frequency response, with the modifications hopefully increasing 
> the high pass characteristics.  I was satisfied when I could see our 
> local Washington quakes which have a higher frequency than the 
> teleseismic events.
> The sensor is the next step from the device I posted some time ago at 
> .   
> Damping is with magnetic braking.  The device does not record a strictly 
> vertical motion because the mass axis is tilted (to improve the low 
> frequency response) giving a response similar to the response from the 
> CSpring Seismometer (which is incorrectly claimed to be a (only) 
> vertical sensing device).  Both the CSpring device and my present device 
> respond to horizontal motion to the extent dictated by the vector angle 
> from the pivot point to the center of mass.
> Your comment about wave form seems to say that the wave forms between 
> your recordings and mine seem to be similar.  If that is what you intend 
> to say, I am somewhat surprised because this station is located between 
> some mountains which I would (I think) cause reflections that would 
> change the wave form.  I have wondered if amateur seismic stations could 
> utilize the interference rendering technique to actually map the surface 
> and subsurface features of the earth somewhat akin to what is done with 
> medical imaging?  My own knowledge of imaging is too weak to venture an 
> opinion.
> Thanks for sharing your results. 
> Roger
> psn-l-digest-request@.............. wrote:
>> .------ ------ ------ ------ ------ ------ ------ ------ ------ ------.
>> | Message 1                                                           |
>> '------ ------ ------ ------ ------ ------ ------ ------ ------ ------'
>> Subject: WinQuake Times
>> From:    "Geoffrey" 
>> Date:    Mon, 9 Nov 2009 13:37:09 -0700
>> Hello PSN;
>> FYI
>> I made the changes to a conversion program
>> of my own to invent a PSN4 file for my data
>> and wish to announce that since I have
>> placed the fractional value of the start time
>> times a billion into the NANO SECOND
>> area the times I now get from winquake appear
>> to be proper. I have tested this using
>> pulse marks made by myself then gone back
>> into the program and checked the times.
>> The proper way would be to use WWV minute marks
>> I have not yet done this however I expect for
>> amateur purposes that would be correct also.
>> I now feel I can resume sending reports
>> to whoever and expect the times to be correct
>> or as correct as can be for my station.
>> GVA teleseismic events appear very close agreement
>> in form to the fellow in Washington State so I am
>> guessing that phase (up is up) is proper also.
>> I only do an SPZ channel so can not compare
>> with those using N or E sensors.
>> Roger Sparks Device seems to have a lower freq
>> response so our comparisons will rarely
>> be exact yet they seem very close in appearance.
>> geoff
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