Hi Said, Thanks for the input! I thought I had remembered someone's post about crystal jump, but I wasn't sure.
Bob >________________________________ > From: Said Jackson <[email protected]> >To: Bob Stewart <[email protected]>; Discussion of precise time and frequency >measurement <[email protected]> >Cc: Time Nuts <[email protected]> >Sent: Saturday, August 31, 2013 1:12 PM >Subject: Re: [time-nuts] Caring for the elderly (OCXO) > > >Bob, > >Pretty standard behavior for some crystals. I recently had such a jump after >150 hours. Some ocxo vendors are way more affected than others. > >Nothing to worry unless it gets worse or happens more often over time. > >Bye, >Said > >Sent From iPhone > >On Aug 31, 2013, at 10:48, Bob Stewart <[email protected]> wrote: > >> My OCXO is a Trimble 34310-T that I bought from a China recycler a month or >> so ago. It has been very stable until this morning. At about 10:30AM my >> PLL showed a large blip during one segment count (1PPS) and the DAC started >> tracking upward to stabilize. Then, 745 seconds later it glitched in two >> successive segments and the PLL has tracked the DAC downward well below the >> old stable number. For an independent reference, I have my 8640B >> self-locked inputting on Channel A of my 5335A with a large enough gate for >> 8 decimal points of display. My GPSDO is serving as the time reference for >> the 5335A. Give or take the stability of the 8640B, the counter seems to >> agree with what my GPSDO is doing. >> >> This is for hobby and learning, so no big deal, but I'm wondering if this is >> how OCXOs start misbehaving in their dotage (so to speak). On the one hand, >> it gives me another insight into error handling for my PLL logic, which is >> good. But, on the other: I'm wondering if I should just give it a proper >> burial and put in my spare? Maybe I'll leave it in to see if any other >> error modes develop, and then toss it when I finally have code I'm willing >> to share. Anyway, is this oscillator on its last legs? I'm more worried >> about letting out the magic smoke and damaging other components than I am >> about accuracy at this point. >> >> Bob - AE6RV >> _______________________________________________ >> 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.
