[Discuss-gnuradio] Artifacts from the USRP Digitizer

[John Clark]

To anyone using the following:

I'm using the USRP with a Microtune UHF band tuner.

What I see is that there is a significant artifact at 512 MHz, and a few 
more, but
another 'clear' artifact at 640 Mhz.

I believe these to be induced by the digitzing clock of 64 MHz.

However, since I avoid 'hardware' like the plague, if others have better 
explainations
and corrections I'd like to hear about them.

In terms of shielding, the Microtune module does seem to have shielding, 
however, on
the USRP board, I do not see much leading into the Analog Devices chips.

We are looking at very low signal levels, and so perhaps others have not 
seen these
artifacts, as they may be looking at much higher signal levels...

Thanks
John Clark.