Alberto,

Thanks for getting me on track here.

I looked at the outputs with a dual-trace scope and the service
monitor feeding it 10 khz off at 7050 khz.

I see what looks close to 90 degree phase difference in the 10 khz
audio out...but large amounts of RF on top of it.  A .01 across each
output cleared that up pretty well (soft66 radio issue!).

Now back to the computer.  With the sig-gen set for 7050, I still see
the mirroring in SDRadio.  Changed to Rocky, and clicked on the "+1
sample offset", and eureka, the image was immediately nulled by Rocky.

Changed the sig-gen to give it a good signal every 5 khz across the
band, and Rocky nulled at each freq.  I now see the un-mirrored
spectrum that I expected.  

I guess that SDRadio doesn't have enough "skew" to make up for the
full 1 sample error.

That also makes me think that every sound card I own has a sample
delay problem.

Guess the next step is to buy a Delta.

Thanks for your help.

73's Steve



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