Date: Sun, 28 Jul 2002 09:07:29 -0600 From: "Jonathan M. Hanson" <jhanson@..............> Subject: WinSDR update
Hi Larry -
Thanks for the WinSDR update. I have not contacted you since I got my
system going so here is a brief update.
A friend of mine (Lew Katz, Pres. Utah Geophysical) has lent me several
geophones to play around with. The most intriguing is an Electro-Tech
EV-17H that he dug out of one of his storage units. I have not been
able to find any information on this unit but it seems to have a
somewhat lower frequency response than the Mark Products geophone I
purchased from you. I have attached a couple of jpegs showing recorded
quakes about 60 miles (Huntsville, UT) and a couple of hundred miles
(Yucca Mtn, NV) as recorded by this unit on June 2 of this year. The
picture labeled june14_02 shows both quakes..the first is the Huntsville
quake and the second is the Yucca Mtn quake. The picture labeled
june15_02C shows the Huntsville quake. I would appreciate any
information you might have on the EV-17H. I did a web search and the
only hit I got on Electro-Tech was one geophone on the SEG "virtual
museum" site. I suspect my unit was built in the 40's or 50's but this
is pure speculation. I have not yet had the time to build a long-period
sensor but hope to do so shortly.
Do you have any short or long term plans of adding some sort of
polarization filter module to WinQuake? This might allow those users
that are recording 3 components to get an estimate not only of the
distance to the quake but also direction. There is a rather large amount
of mining activity in Utah and surrounding states. A directional filter
would help me sort out the mining-associated activity from other activity.
Best regards,
Jonathan Hanson