USRP2 with strange RX behavior (ADC damaged?)

Hi everyone,
I’ve been playing with my USRP2 for a while and last week I noticed a
strange behavior. The early signs were that my USRP2 was deaf so I tried
switch the daughter-board from a WBX to a LFRX and the problem seems to

  • When one antenna is connected to RX, the scope is flat with a
    fft => -400dB.
  • When a -50dBm sine CW is sent to RX, ~=-80dBm (and plenty of
    harmonics) is
    readed by USRP2. Furthermore, the sine wave (on the scope) seems to be
    sampled in amplitude.

Looking around on the mailing list i found something about the USRP ADC
fullscale and PGA :
"If you turn the programmable gain amplifier (PGA) down to 0 dB (the
default),then a full-scale signal would be 2 V p-p. If you turn the PGA
to +20dB gain, then full-scale would be .2V p-p

-Is the USRP2 ADC fullscale/PGA works like USRP1?
-If yes, is it possible to damage the USRP2 ADC if some signal is sent
to it
through a wrong PGA adjustment?

Finally, if my USRP2 is damaged (I’m pretty sure the ADC is toasted)
what is
the way to repair?
Send it back … but where? How do you usually do with damaged


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