Hi If your TCXO is off by 1 ppm, it will slip 10 cycles per second at 10 MHz. If it is off by 0.1 ppm it will slip a full cycle at 10 MHz. If it is off by 0.01 ppm *and* uses some sort of digital compensation, it will hop around. If the GPS is not sawtooth corrected it will hop by a good fraction of a cycle at 10 MHz If the GPS is not surveyed in and seeing many satellites, it may hop by more than a cycle at 10 MHz.
Best bet: Divide the TCXO down to a much lower frequency (< 100 Hz). Use the 5370 to look at the delta between the GPS pulse and the TCXO output. Bob > On Nov 3, 2016, at 9:22 AM, Peter Reilley <[email protected]> wrote: > > I am using the 1 PPS for the trigger. > > Pete. > > > On 11/3/2016 8:59 AM, Antonio A. S. Magalhaes wrote: >> >> Pete, >> >> Tell us about your trigger: where is it? >> >> Regards, >> >> Antonio/CT1TE >> >> --- >> >> A 2016-11-03 12:20, Peter Reilley escreveu: >> >>> I am the proverbial man with too many clocks and I don't know what time it >>> is. >>> To correct this situation I have decided to calibrate everything. >>> >>> I have a HP 5370B, a HP 6370A, and a HP 5328A all with the TCXO option. I >>> also >>> have some TCXO modules. I figured that I would calibrate them against my >>> Trimble >>> Resolution T GPS receiver. >>> >>> I put the 1 PPS signal in one channel of my scope and one of the 10 MHz TCXO >>> signals in the other channel and look at the phase relationship. The TCXO's >>> are >>> already close enough that I should not be out by more than a fraction of a >>> waveform. >>> I understand that I have to deal with the 1 PPS without sawtooth correction. >>> >>> I expected to see the 10 MHz signal bounce around but not move more than 1/2 >>> of a wave length. Instead I see the 10 MHz waveform appear steady for a >>> few seconds >>> then jump a significant portion of the wave. The jump is too much to be >>> confident >>> that I have not slipped one cycle. >>> >>> Can I do what I am trying to do or am I missing something? >>> >>> Pete. >>> >>> _______________________________________________ >>> time-nuts mailing list -- [email protected] <mailto:[email protected]> >>> To unsubscribe, go to >>> https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts >>> and follow the instructions there. > > _______________________________________________ > 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. _______________________________________________ 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.
