Hi Cool !!
> On Feb 10, 2021, at 6:54 PM, Skip Withrow <[email protected]> wrote: > > Hello Time-Nuts, > I just finished an almost 27 day run of one of my Rb oscillators and, > at least, I was impressed. > > This oscillator is a stock standard LPRO-101 with only one slight > modification. The 5k C-field pot was brought out external to the unit > and replaced with a precision 500 Ohm 10-turn pot with fixed resistors > on either side to make the total 5k. The frequency change is about > 1.62x10E-13 per division on the turns counting dial. > > The oscillator IS in a controlled environment (with a little secret > sauce poured on). Ok, I’ll ask …. what’s the environment? Bob > > The oscillator is running completely open loop. In fact, there is > purposely nothing hooked to the EFC line. During the run nothing was > touched in the system. > > There are two attachments. The first is a TimeLab ADEV plot. The 4 > hour plot is the oscillator against a free running 8602 measured with > a DMTD and TICC (this gives the real short-term performance with the > GPS noise removed). The 26 day plot was done by logging the > oscillator against GPS with a Thunderbolt every 15 seconds. The phase > data was imported into TimeLab. Of course, this plot has the GPS > noise in it as well, but gives a good indication of the unit > long-term. > > The second attachment is the phase data plot. Over the almost 27 days > it moved about 130ns. And the curve looks reasonably parabolic, which > would indicate the aging is pretty constant. Aging calculates to > about 4.15x10E-15 per day. Reasonably good by my standards (but I'm > trying to do better)! > > When I monitor my HP5065A with a Thunderbolt side by side with this > rubidium I can see the 5065A move with barometric pressure changes and > ambient temperature changes much more than RUFUS. And the 5065A > flicker floor seems to be worse (but, of course, I haven't measured > the 5065A yet). > > Just had to brag a bit on this one. > > Regards, > Skip Withrow > <RUFUS vs 8602 - ADEV.png><RUFUS vs 8602 - Phase > Data.png>_______________________________________________ > time-nuts mailing list -- [email protected] > To unsubscribe, go to > http://lists.febo.com/mailman/listinfo/time-nuts_lists.febo.com > and follow the instructions there. _______________________________________________ time-nuts mailing list -- [email protected] To unsubscribe, go to http://lists.febo.com/mailman/listinfo/time-nuts_lists.febo.com and follow the instructions there.
