[time-nuts] Question on crystal jumps
bruce.griffiths at xtra.co.nz
Fri Oct 24 00:51:17 UTC 2008
Joseph M Gwinn wrote:
>> It may be better (aside from costs) to just use a very large sapphire
>> whispering gallery resonator.
> A higher frequency could be an advantage in the "crystal" oscillator of a
> Rb oscillator. One can then divide the higher frequency down to 10 MHz,
> perhaps improving phase noise in the process.
> I suppose a SAW could be made of sapphire, if it's piezeoelectric enough.
Saphire isnt piezoelectric.
The idea being that there may be some advantage in not using an acoustic
wave resonator but a microwave resonator with extremely high Q (at least
at Liquid helium temperatures).
However the cost will usually be prohibitive.
Cryogenic sapphire whispering gallery resonators are known to have
greater short term stabilities that even the best crystal oscillator.
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