Re: [Discuss-gnuradio] Problem using the dbs card

[Eric Blossom]

On Wed, Oct 12, 2005 at 06:34:36PM +0200, EVENNOU Frederic RD-TECH-GRE wrote:
> Hi everybody,
> 
> I started using the gnuradio platform some few weeks ago, and I've been
> trying to use the dbs_rx card. I made some few tests to practice myself
> on the way to use this card, but unfortunately I didn't have any
> successful result.
> I've been using a python program named dbs_fft.py to have a look at the
> spectrum in a range of frequencies that I specify. I made some few tests
> by emitting a sine wave at 1GHz (and then around this frequency), but
> I've never been able to get it with the dbs card, whereas I can see it
> very clearly on a spectrum analyzer (level == address@hidden). At emission,
> and reception, I have some antennas working in that band and antennas
> are separated by 50cm. On my display screen I just receive some noise so
> I must receive some samples from the dbs_rx card.
> I made the same test at lower frequencies and using the TVRx card to
> receive the signal, and it works pretty well.
> Did someone have the same problem with this card, and is there anything
> special that can be done to check if my dbs_rx card works properly ?

You might want to try using usrp_fft.py (in CVS) instead of
dbs_fft.py.  I'm currently revising *all* the examples, but haven't
had a chance to look at dbs_fft.py yet.   Right now, usrp_fft.py
doesn't have a way to control the adjustable IF bandwidth of the dbs
card, but other than that, it should work fine.

Use the -R option to specify which side you want to receive from.  E.g.,

  $ ./usrp_fft.py -R a

Eric