Mon Apr 27 04:27:16 UTC 2009
long term aging.
When you want to know what the aging will be over the next 10 years,=20
Allan needs to have 30 or 40 years of data. Not the most practical way.
I have found for long term aging, taking data at around once per month =
generally does a good job, IF the osc is a "good osc"
Not sure if the attached under 60k plot will be seen.
It is plot of actual data for 3 of my Osc over a 5 to 9 year time span. =
(Ref was GPS)
The 10MHz SC10 shows a very consistent -8.3e-11 per day aging rate, =
after a two year 'warm up.'
The Dana 1992 high stability option shows a less consistent +2e-10 per =
and the 5MHz, a small OXCO, has a Zero aging rate averaged over the last =
6 years, and shows it can be pretty misleading to talk about just aging =
rate per year if the stability is not there.
More information about the time-nuts