[USRP-users] (SOLVED) USRP1 and UHD rx_samples_to_file

Steven Clark steven.p.clark at gmail.com
Tue Nov 16 14:23:46 EST 2010


On Mon, Nov 15, 2010 at 5:11 PM, Jason Abele <jason at ettus.com> wrote:

> On Mon, Nov 15, 2010 at 04:53:25PM -0500, Steven Clark wrote:
> > >
> > > Steven,
> > >
> > > The UHD and libusrp1 drivers from GNUradio have different default gain
> > > settings.  UHD defaults to 0dB and libusrp1 defaults to mid-gain, which
> > > I think will be around 25dB.  These give very different Noise Figures
> > > for WBX.  Try the rx_ascii_art_dft with --gain=25
> > >
> > > Jason
> > >
> >
> > I was explicitly commanding gain=0 in both cases. Besides, I'm putting in
> CW
> > in range ~-20dBm, which should be plenty visible regardless of gain
> setting.
> > Right now it just looks like 2-3 ADC bits worth of noise with the UHD
> > driver.
> >
> > Grr, this is frustrating. I want to start developing with UHD + USRP1,
> but
> > this is a showstopper atm :(
>
> Hmm, it is strange that the UHD WBX is not working for you.
>
> Did you reclock your USRP1 to something other than 64MHz?
>
> Do you have BasicRX or any other daughterboard, does it work with UHD?
>
> Could you try setting wbx_debug to true on line 88 of:
>    <UHD_SRC>/host/lib/usrp/dboard/db_wbx.cpp
>
> and then rebuild and install UHD.
>
> This should give copious output, even just runing uhd_usrp_probe.  Paste
> the output of uhd_usrp_probe into an email to me
>
> Sorry to hear this is still giving you trouble, but I am happy to help
> you get it up and working.
>
> Thanks for your patience.
>
> Jason
>
Fixed it. Tipped off by
http://www.ettus.com/uhd_docs/manual/html/dboards.html:
"The user may set the receive antenna to be TX/RX or RX2. However, when
using an WBX board in full-duplex mode, the receive antenna will always be
set to RX2, regardless of the settings."

The solution was as simple as switching the input from TX/RX to RX2. Strange
that it worked fine with the old software setup. I guess something about the
default handling of full-duplex vs half-duplex changed with UHD?

ascii art and my capture app work fine now...thanks all!

-Steven
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://lists.ettus.com/pipermail/usrp-users_lists.ettus.com/attachments/20101116/cdd233cc/attachment-0002.html>


More information about the USRP-users mailing list