[vna] FW: 3 small questions and 1 BIG question

[Jack Klinker]

1. R41 10 ohms (BOM) vs. 27 ohms (schematic)?  Which is correct?
 
2. I figured the SGA-5386 Rbias as 24 ohms.  5v - 3.6v @ 60 mA = 23.3 ohms.
Did I do this right?
 
3. All resistors are specified a s  1%.  It looks like that 5% would be fine
in most(all) places.  Am I missing something?
 
The BIG question:
4. The VNA seemed to be working fine, but then things changed.  It seems to
be a strange gain effect: about a  20 dB jump when there is a higher level
input.  See attached  .jpeg print screen image.  The filter under test (18
MHz 4 element XTAL filter) was showing a normal transfer function, then this
started happening.  I tried a different filter.  I mostly re-built the
filter.  I replaced the front-end SGA-5386 in the VNA, but nothing changed.
Did something die in the 8302 log detector?
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