Pluto with 2 RX channels using GNURadio

What gnuradio version are you using ? Can you share a basic flowgraph to reproduce this ?

-Adrian

Hi Adrian.  I am using GNU Radio 3.10.1.1.

I have made some tests and my conclusion is that FMComms outpus an incorrect complex signal from channel 2.  "Q" component is correct, but "I" component on CH2 comes from RX1.

If I disable CH1, the problem goes away and CH2 works properly.

You can download the flowgraph here.

I wrote a description of the steps I followed.  You can see it here .

You can see all my screen captures here .

Is this a bug on FMComms working with Pluto or am I missing some configuration?

Hi Adrian.  I am using GNU Radio 3.10.1.1.

I have made some tests and my conclusion is that FMComms outpus an incorrect complex signal from channel 2.  "Q" component is correct, but "I" component on CH2 comes from RX1.

If I disable CH1, the problem goes away and CH2 works properly.

You can download the flowgraph here.

I wrote a description of the steps I followed.  You can see it here .

You can see all my screen captures here .

Is this a bug on FMComms working with Pluto or am I missing some configuration?

Hi,

We are now investigating it.

-Alexandra

I found the problem.  There is a bug in file:

gnuradio/gr-iio/fmcomms2_source_impl.cc

You can see the fix here

Thank you.

-Ariel

Hi,

I added a fix for the issue on this branch: https://github.com/AlexandraTrifan/gnuradio/tree/fix-fmcomms-ch2-complex .
If you can confirm it works fine, I can send a patch upstream.

In the link that you sent I can see the highlighted lines where the data was not properly converted. Did you create a commit with the fix?

Edit: I just now found your pull request: https://github.com/gnuradio/gnuradio/pull/6137 .

Thank you!
-Alexandra

Yes, that is the pull request.  Regards.

- Ariel