[time-nuts] Crystals like WIne

[Brooke Clarke]

Hi Tom:

Your comment about how the original specs on a crystal oscillator don't mean too much after 10 or 20 years makes me think crystals are very much like wines.  You only really know about them after they have aged.

But in the case of crystals they need to be running.  I have been watching the frequency of a Sentry 1/2 size unit oscillator every morning for over a year and the delta frequency in Hz vs minutes of operation equation looks like: y = -35.858Ln(x) - 84.952
R2 = 0.9933  The down slope in frequency is now much shallower than it was when first powered on.


The problem I ran into with the Gibbs double oven frequency standard was 
that the Bliley glass
enclosed 10 MHz crystal drifted to the point where it could no longer be 
brought back on frequency.

Today my FTS4060 is supposed to be delivered,

Brooke Clarke, N6GCE

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