[Discuss-gnuradio] usrp broken, only outputs zeros

[Martin Dvh]

Hi Matt and all,
I am afraid my usrp is broken.
It was working fine a few hours ago.
I was looking at a spectrum (fftwin) using the tvrx.
Suddenly the spectrum went down (samples went to zero) and they never returned 
to normal values since.
I was using the tvrx in RXB
in RXA was the basic RX
in TXA was basic TX
TXB was empty.

I tried it both under linux and windows. Same results mostly zeros.
Not all samples are zero though.
Mostly I see zeros, sometimes I see a block of normally looking samples and 
then a block of samples which keeps repeating itself like
00 00 00 40 00 00 00 00
00 00 00 40 00 00 00 00
00 00 00 40 00 00 00 00
00 00 00 40 00 00 00 00
00 00 00 40 00 00 00 00

One of the tests I ran was rx_cfile.py
(I happened to run this on windows)
TVRX was this time in RXA (with a connected antenna)

$ ./usrp_rx_cfile.py -m 0xf0f0f0f0
found 5 busses

$ mv usrp_rx.dat  usrp_rx_mux_0xf0f0f0f0_tvrx_in_rxa_problems2.dat
$ bzip2 -z -k usrp_rx_mux_0xf0f0f0f0_tvrx_in_rxa_problems2.dat

see http://www.olifantasia.com/pub/projects/gnuradio/mdvh/usrp_problems/ for 
the compressed file with the samples
(Beware: although the compressed file is only 18k (because of all the zeros) it 
will expand to 376 MB.)

check counting seems to work though.
Although it seems it takes quite some samples before it finds LOCK.

+6V and +3.3 V are all there.

The led blinking seems normal to me.

first led blinks fast
second led blinks 1 time (about a second)
first led blinks slow

I thought maybe the soldering of the shorted resistor (which we did on 
what-the-hack) on the extra clock board failed but with a multimeter I measure 
0.7 ohm
across the short.

Any ideas what might be wrong or where to check/measure?

Greetings,
Martin