On Fri, 2010-11-12 at 19:56 +0200, john kimionis wrote: > Hi, > I am trying to capture a RFID Reader-Tag Conversation at 866.3MHz. I'm > testing 2 cards: A FLEX 900 and a DBSRx rev2.2. With the FLEX900 i'm > able to clearly see the Reader signals and the tag replies, but with > the DBSRx the signals showed distorted by some higher frequency > signals. > > Using usrp_fft.py with the same settings and USRP/Antennas at the same > exact position what I surprisingly saw was that the DBSRx is capturing > an image of the RFID spectrum 400 kHz away! > > What could this mean? Is something on the front-end damaged? > >
It's possible. If you're using a USRP1, try swapping daughterboard sides to make sure the problem follows the daughterboard. It looks as though either the I or Q channels are not operating. --n > Here are the two screenshots of usrp_fft.py. one for FLEX 900 (good > one) and one for the DBSRx (problematic) > http://twitshoot.com/1f > http://twitshoot.com/1g > > > > > > _______________________________________________ > Discuss-gnuradio mailing list > Discuss-gnuradio@gnu.org > http://lists.gnu.org/mailman/listinfo/discuss-gnuradio _______________________________________________ Discuss-gnuradio mailing list Discuss-gnuradio@gnu.org http://lists.gnu.org/mailman/listinfo/discuss-gnuradio
