> Using the scope display, I measured the detector output difference
> between nothing connected (which on the BASIC_RX means that
> the A/D is "seeing" the 50-ohm termination across the input-half of
> the balun transformer), and my -46dBm signal connected.
I see your point and your logic, but this seems to be assuming too much.
What if you adjust your signal generator to -110 dBm? That's a fairly
low value, but it should be easily acheivable on most RF signal
generators.
> That difference amounted to a 65dB difference in detected output power.
> Doing the math, does that mean that a "naked"
> USRP2 + Basic_RX is sensitive down to roughly -111dBm, or should I
> factor in root(5KHz), which brings it up to -92dBm.
If you're looking at CW, 5 KHz is huge, and probably as you bring down
the bandwidth you'll get the same output as long as you're in the
passband.
This is how ARRL does receiver tests; it's probably at least good to
understand how you're differing:
http://p1k.arrl.org/~ehare/testproc/testproc.pdf
You could probably convince them to run a set of tests on a USRP-based
radio, sort of a product review without a product and without really
doing the rest of the review.
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