> OK, so I tried this myself. A sloppy setup but never the less... The > CNT-90 time-base output via a T-connection on B-channel and then over to > the A input of the HP 5328, selected START A and then the T.B. OUT over > to CNT-90 channel A. At 100 kHz setting on the HP 5328, the TI A->B > measurement on CNT-90 shows some jitter, but RMS jitter is below 400 ps > at least and ADEV readings somewhat below that.
There's one other potential error source in Bert's case that might make his results look a bit worse than they really are. TI addresses the 5370 in talk/listen mode, and I've noticed that it can sometimes get into a state where the counter appears to skip every other reading. I've only seen this happen with 1-pps sources driving both channels but it could conceivably happen on a 10 MHz test as well. The result would be 2 seconds' worth of noise/drift between readings instead of one, which would artificially make the graph look a bit worse. So if the counter's display seems to change only after every other START cycle, that could be happening. The next test version will allow the counter to run in talk-only mode with arbitrary measurement periods, which should avoid this behavior completely. -- john, KE5FX _______________________________________________ time-nuts mailing list -- [email protected] To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there.
