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Martin Shepherd wrote:<br>
<blockquote type="cite"
cite="midPine.LNX.4.58.0312301052550.3391@goblin.caltech.edu">
<pre wrap="">On Tue, 30 Dec 2003, Brian Mason wrote:
</pre>
<blockquote type="cite">
<pre wrap="">Also, Tim- at some point I think we'd like word from you whether a)
the detector circuit design and b) theoretical noise calculation based
on that, both discussed at our last telecon, are an acceptable basis
on which to proceed (for one thing so we can get orders in for the
long lead items like bessel filters).
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<pre wrap=""><!---->
The most recent detector circuit design that I have seen was marked
preliminary, and had a couple of known problems relating to
accomodating the Bessel filters. Fixing these probably won't increase
the noise significantly, but it would be nice to see the final design
to be sure. There also remain discrepancies between my noise
calculation for the first stage of amplification, and Randy's. To have
any confidence in the noise calculation, we need to get the same
numbers.
Martin
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</blockquote>
Martin,<br>
<br>
I'm currently in the process of tweaking the current rev G schematic to<br>
incorporate the changes required to correctly accommodate the Bessel <br>
filter... The new schematic (rev H) should be available for all to
review<br>
sometime tomorrow (06-JAN-04)...<br>
<br>
Regarding the discrepancies in our noise calculations, I've had a chance<br>
to review, in great detail, both your model (and calculations) and my
model <br>
(and calculations); and am currently in the process of preparing a
writeup <br>
which seeks to explain and resolve these discrepancies. This should be<br>
ready for all to review sometime later this week...<br>
<br>
Randy<br>
<br>
<br>
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