Hi all, I went to the Dataq website, here is a link that will take you
there:  www.dataq.com/edn
I don't want to deter anybody from existing solutions, but the little AD
module they offer looks pretty good. And cheap.
The low cost Data Acquisition starter kit, for $24.95 includes a small
module with 4 channels, 10-bit ADC, max. +/-10VDC
input range (makes scaling and math easy), "up to" 240 samples/sec., and 2
digital inputs for start/stop/event bits. The interface is a Serial port,
but it allows the DA unit to be powered by the serial port too, probably
fast enough for seismic events. It includes the hardware/module, software
(2 CD's) cable and even a screwdriver. It supports Win OS from Win95 to XP.
There is a sizable online library of support for it including applications
notes for various sensors or transducers.
The 4 channels would allow you to conceivably have 2 separate sets of
vertical and horizontal geosensors in different areas, although the module
itself would have to be within (realistically) about 50 feet of your
computer for serial data, plus the sensor wiring length. 
Looks like a good inexpensive way to get a seismic sensor mini-array up and
running.      Tom Detweiler in Grass Valley

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