B input on BasicRX not working

Hello everyone,

We’ve run into a problem with the “B” input on the Basic RX board with a
USRP. Specifically, a test tone running into the “A” input shows up fine
in the fft application, as well as in a captured file. However, a test
tone running into the “B” input doesn’t have any power in the FFT or in
the captured file. Digital sample values on the ‘bad’ input are all
either 0,1, or 2.

We’ve tried tones at 250 MHz and 1 MHz, and we’ve tried two basicRX
boards as well as 2 USRPs. We’ve also looked at the BasicRX boards to
verify that the input signal actually makes it to the high density
connector.

Any thoughts?

To capture I’m using:

./usrp_rx_cfile.py -R A -d 8 -f 0 -s -N 1000000 filename.dat

(Of course, that’s the example when the BasicRX is in the A slot.)

-Roshan

Roshan B. wrote:

boards as well as 2 USRPs. We’ve also looked at the BasicRX boards to
verify that the input signal actually makes it to the high density
connector.

Any thoughts?

To capture I’m using:

./usrp_rx_cfile.py -R A -d 8 -f 0 -s -N 1000000 filename.dat

use -R A:1 for the “B” input. It defaults to real-input mode, which
treats the 2 SMA inputs as separate signals.

using -R A is the same as -R A:0

Matt