Hi all-
I have a multi-usrp setup with 2 USRP 1s and 4 WBX daughtercards. I have
performed the clock synching described here:
http://gnuradio.org/redmine/wiki/1/MultiUsrp
I'm doing 4-channel receive, using a power splitter to send the same CW
signal into all 4 d'cards, and tuning them all identically.
3 of the 4 channels are nicely phase-locked. The 4th seems a little...off.
ClockMasterUSRP (Serial #5821): Side A: "red" channel
ClockMasterUSRP (Serial #5821): Side B: "green" channel
ClockSlaveUSRP (Serial #2087): Side A: "blue" channel
ClockSlaveUSRP (Serial #2087): Side B: "black" channel <--- problem with
this guy
Please see these 3 images to see the problem:
http://picasaweb.google.com/steven.p.clark/MultiUsrpGlitches?feat=directlink
You can see the problem in both the frequency domain, and in the time
domain.
I tried swapping daughtercards around, and the problem is not tied to
any one daughtercard, but rather to slave USRP side B.
Any idea what could be causing this? Shouldn't the same clock be going
to both sides of the USRP? (why does blue look fine, but black does not?)
-Steven