Hi Corby, That was really what I was hoping for from the small Rb's too, but there appears to be other things at work with them.
I had not really considered that they might be sealed, but it's something to look at. I had been thinking more about how it was fixed into the package and with what materials. As well as the normal component and circuit issues, there are also some deliberate ones like discrete steps in temp correction which all add to the fun and confusion. BTW, if anyone has or knows of any pictures of a teardown of a FRK or LPRO physics package, I'd be very interested. Anyway, it's good to see that the 5065A is better behaved - I'm just more jealous now! I look forward to seeing the results of your tests. Angus. On Sun, 22 May 2016 08:58:16 -0700, you wrote: >Angus, > >The HP 5065A has a fairly open path from atmosphere to the cells as far a >barometric pressure is concerned. >Response is rapid to a change. > >The mechanism is "oil-canning" of the windows on the ends of the cell. >Depends on diameter of the cell, thickness of the windows, and stiffness >of the particular glass used. (for a particular gas mix of course) > >It is VERY repeatable, and VERY linear. > >I have heard that one European observatory routinely tracks the >barometric pressure by watching their 5065A shift. > >After seeing Wulf's data I can believe it! > >My circuit is eliminating that variable quite nicely. As others have >said, temperature will be a different matter. > >I'm currently doing temperature tests and plan to eliminate the major >causes rather than compensate. > >Early measurements show as-built to be better than the spec of >1.6X10-12/degree C. > >Cheers, > >Corby > >_______________________________________________ >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.
