[time-nuts] Frequency referenced temperature regulator

[Poul-Henning Kamp]

In message <6B9C616F-5C27-4F36-9594-FDA27D949AF7 at febo.com>, John Ackermann N8UR
 writes:
>Sounds like the way the HP 2804 quartz thermometer works.  HP came
>up with a special crystal cut that was very linear with temp, and
>I suspect the hardest part of your idea might be the linearity of
>the tempco of your crystal.  But you could characterize that and
>store in a correction table.

Indeed, it was the HP2804 that gave me the idea.

The correction table would more or less be the frequency I key
into my HP3336 to get a given temperature.

My plan was to add a separate pt1000 element to measure the absolute
temperature.


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