Re: [Discuss-gnuradio] if uhd_transmitter instantiated after receiver, TX works, otherwise RX works

[George Nychis]

Your attached patch also fixes the problem!  Thanks a bunch for helping narrow down this issue :)

On Mon, Jun 18, 2012 at 3:59 PM, George Nychis <address@hidden> wrote:

Hi Josh,

Thanks a bunch for these pointers/patches and looking in to it!  We are currently testing them out, shouldn't take long.  However, we did verify that reverting to the older version (003.003.002) did work for us as it did for King (thanks!).

Stay tuned... we'll let you know ASAP.

- George

On Mon, Jun 18, 2012 at 1:51 PM, Josh Blum <address@hidden> wrote:

> Thanks for the tip. I think I figured it out.
>
> The property to use an LO offset was true for TX and not RX. This would
> mean that tuning an individual chain and using it would be fine; but
> since there is a shared LO, the offset would not be compensated for by
> the DSP on the chain in the other direction, hence, it not working.
>
> If you dont mind trying, here is a simple 1 liner patch:
> http://pastebin.com/KiR3e6j0
>

Another quick way to test this without the patch would be to tell the
tune request to use an LO offset of 0. Example:

usrp_source/sink.set_center_frequency(uhd.tune_request(my_freq, 0))

-josh