Or perhaps use the Symmetricom CSAC ... Relatively expensive but might work
> On Mar 21, 2017, at 8:08 AM, Attila Kinali <[email protected]> wrote: > > On Tue, 21 Mar 2017 13:38:51 +1100 > Hugh Blemings <[email protected]> wrote: > >> This got me to wondering if a Rubidium based standard might do the trick >> - the Efratom SLCR-101s seem readily available for ~USD$200 mark. > > As TvB wrote, a single one will not do the trick. You will need > a stability 1e-14 @1d. IIRC most Rb standards floor out at 1e-12 to 1e-13 > somewhere between 1k and 100k seconds. Even the Super-5065 has a floor > of about 3-4e-14 (unless our friends here improved on this already). > > There will be a few things that you will need to do, if you want to go > with Rubidiums: > 1) Stabilize or compensate for environmental effects (temperature, air > pressure) > 2) Build ensembles of Rb clocks. > > The former is to prevent the ADEV from "turning upwards" again and > keep the Rb's as stable as possible as long as possible. I have no > experience how much this helps, but I suspect, with the correct modeling > that you could get the ADEV to be flat up to a day, maybe even two. > You will have to include aging and drift of the cell itself in the model. > This also means that you will have your Rbs running for a few weeks/months > prior to any measurement so that the aging settles down a bit. > > The ensemble is to get the ADEV down. Averaging of clocks with the same > noise decreases the ADEV by the square root of the number of clocks used. > If you are close to the ADEV you need, the averaging will help you getting > it further down. Unfortunately, getting from 1e-13 down to 1e-14 is > impractical as you'd need 100 clocks to average over.... But a factor > of 2 to 3 should be possible. > > > Alternatively, you can ask Oscilloquartz whether they let you borrow > two of their new OSA3300 for a publicity stunt :-) > > Attila Kinali > -- > It is upon moral qualities that a society is ultimately founded. All > the prosperity and technological sophistication in the world is of no > use without that foundation. > -- Miss Matheson, The Diamond Age, Neil Stephenson > _______________________________________________ > time-nuts mailing list -- [email protected] > To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts > and follow the instructions there. _______________________________________________ time-nuts mailing list -- [email protected] To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there.
