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Mitch, <br>
we typically used to run east tennessee S-13 stations with a gain of
66db to 72 dB( 2000 to 4000) to produce a background noise of about
5mVp-p. I suspect the noise is mainly higher frequency wind induced.
<br>
a reftek with its input set for 40vp-p differential will have its
least significant bit be a little over 4.7uV if you run with no gain
you would expect the output of the seismometer to be .005/2000 or
2.5uV. this will give you less than 1 bit of recorded background
noise. i would therefore suspect that to record at least a little
background noise you would want to run at least a gain of 32.<br>
Greg Steiner<br>
<pre class="moz-signature" cols="72">--
Greg Steiner
VLF Designs
1621 Bella Vista Dr
Jackson, Mo. 63755
Ph:573-204-1286</pre>
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