Thanks to all that replied. The problem is my 5328A reference input amplitude, and possibly the input module. I lowered the reference amplitude to 4.9v p-p and the accuracy got better, but not the same as the 5372A. So I suspect that the input front end may have something wrong with it. I have a spare 041 module so I will replace the current one at a later date.
I did confirm that the 5372A is good by comparing the reference frequency as an input signal to the counter. It is dead on at 10.000000000MHz, and I also confirmed it against my 5370B counter as well. The same thing there. So my 5328A is suspect. Thanks again. Jerry At 05:05 PM 3/21/2012, you wrote: >I have a question for the collective group. > >I have a HP 5372A and a HP 5328A frequency counters. Both counters use the same >PRS-10 Rubidium frequency standard driving a 6 channel reference distribution >amplifier >to each counters reference input port. The problem is this; > >When I measure the same frequency on both counters, (done one at a time) the >frequency >is generally off by about 300 Hz or so between the counters. Now I would >expect an error >of +/- 1 digit, but 300Hz seems a bit strange to me. I can not find the >problem and the >difference exists even if I use the internal timebases of each counter, give >or take the timebase errors. >The frequency is always at least >200 to 300Hz off between the two counters >and I don't know >which one to believe. You know the "man with 2 clocks" problem. > >Anyone have any idea what may be causing this? > >Thanks >Jerry > > >_______________________________________________ >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. Jerry Mulchin _______________________________________________ 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.
