Hi If you watch the prediction number as the unit warms up, on some boxes it will go through a minima fairly early on. I’ve seen it hit at a few days. I’m sure it depends a lot on how long the box has been off and the particular OCXO in the box. That prediction I do not believe at all. It goes away in < 12 hours….
The “you can believe it” sub 1us prediction seem to come after it’s been constantly on power for a while (like weeks). Again how fast it gets there will vary unit to unit. All of that said, I don’t think I’ve seen any of mine hang out consistently above 2 us for any noticeable period of time after they have been on a month or two. No, I don’t make a habit of constantly checking up on them…. Bob > On Apr 4, 2015, at 8:21 PM, Charles Steinmetz <csteinm...@yandex.com> wrote: > > Bob wrote: > >> I've seen the same sort of < 1 us holdover estimates out of mine as well. >> I for one do *not* believe that it's going to do 200 ns holdover in 24 hours > > No, nor do I. But I do expect <1uS. Mine seems to stay within <500nS over > the first 24 hours with regularity, although I haven't tested it very often. > >> the objective of the prediction function was to decide if it could >> make 10 us over 24 hours >> * * * >> In this case, a >11 us estimate says "I'm not going to make it". That means >> the >> box is telling you it is not able to do what it should. > > One expects a safety factor between the minimum spec and typical operation. > I'd be concerned if a 58503 was consistently predicting >2uS (to me, >2uS > means "I may still meet spec, but I'm not as stable as I should be"). > > Best regards, > > Charles > > > > _______________________________________________ > time-nuts mailing list -- time-nuts@febo.com > To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts > and follow the instructions there. _______________________________________________ time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there.