[time-nuts] Counters for ADEV measurements
Tom Van Baak
tvb at LeapSecond.com
Tue Oct 2 10:03:09 EDT 2012
> I'm also interested in this. I've got one of these and a 53131A and
> am still learning the ins and outs of ADEV measurements with timelab.
> I was not aware of the 5/10MHz shortcomings of the 53131A that were
> discussed this weekend..
To be fair, HP/Agilent did not hide this fact, but I agree it is buried rather deep in the 53131A/53132A manual. The new series (e.g., 53230A) has a similar issue. There's a wonderful paper by Robert Leiby about this design artifact:
"... Frequency Error near the Reference Frequency Harmonics"
This is no reason not to use a frequency counter in the lab. It simply explains why this class of counter works amazingly well at arbitrary frequencies and not quite as well right around magic numbers like 5 or 10 MHz.
More information about the time-nuts