[time-nuts] Question on crystal jumps
SAIDJACK at aol.com
SAIDJACK at aol.com
Fri Oct 24 08:33:43 UTC 2008
Hello Neville,
interesting info! Yes, chemical processing apparently can "fix" jumpy
crystals. Wish we had more crystal processing experts post their experience here.
It is interesting to note that some of these jumps on the order of say 0.1
parts per billion or less are probably caused by only a couple of molecules
reaching or leaving the crystal.
In a GPSDO, a very small change of only 0.1ppb will cause a massive change
in phase of 50ns within 8 minutes.
On our Fury/FireFly GPSDO such a phase error would be arrested very quickly
to prevent it from getting worse, and then the servo loops would push-back
this phase offset to 0ns over an hour or so to minimize the frequency error.
bye,
Said
In a message dated 10/23/2008 22:33:23 Pacific Daylight Time,
namichie at gmail.com writes:
Does chemical etching reduce the frequency of micro-jumps?
Can quartz crystals be thermally annealed?
What is interesting is the ageing mechanisms. Does gross thermal
cycling reduce ageing?
just some thoughts,
Neville mIchie
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