Hi A failed ( = cold) oven on either a normal OCXO should give you a “tens of ppm” sort of frequency error. At 10 MHz that would be over 100 Hz. Fractions of a ppm are less likely to be oven issues.
Bob > On Nov 5, 2018, at 1:01 PM, Dr. Frank <frank.stellm...@freenet.de> wrote: > > Walter, > > did you check on both failing oscillators, that the ovens work properly > afterwards, or that the cases still get warm? > > I once had a failing 10811, where the NTC was defect, maybe also after a > longer unused time. > > As the heater draw an excessive current on turning on, (about 500mA for the > 10811), maybe the thermal fuse blew up, but due to the peaking current, not > due to temperature. > > I find it quite unusal, that the oscillator / XTAL itself should make a jump > like this. > After 48h at most, it should return to its recent frequency trimming, within > < 1E-8, or less.. as these guys are really old. > > That's the typical behavior of all three 10811, which I own (inside 5370B, > 5335A, and one external). > > Frank > > > _______________________________________________ > time-nuts mailing list -- time-nuts@lists.febo.com > To unsubscribe, go to > http://lists.febo.com/mailman/listinfo/time-nuts_lists.febo.com > and follow the instructions there. _______________________________________________ time-nuts mailing list -- time-nuts@lists.febo.com To unsubscribe, go to http://lists.febo.com/mailman/listinfo/time-nuts_lists.febo.com and follow the instructions there.
