[time-nuts] Mystery hp Ovens For Sale

[Ian Stirling]

  It looks like the quartz is in the sealed glass "valve", or "tube".

  I have removed a similar glass vacuum enclosed 100 kHz frequency
marker generator from my Eddystone EA12 receiver that I bought from
Tom Roberts, G3YTO (SK 1985), in September 1978. I don't use the EA12
any more and I wonder what kind of timing device I can make from this
beautiful slab of quartz, approximately 28 x 5 x 2 mm. I don't have a
data sheet for it, but I can see which pins are connected to the quartz.
In the receiver, it has a spring stabilized black metal cover that mates
to the socket. I suspect that is so that the thirteen valves and their
heaters create a thermal equilibrium and the black shroud lets the
crystal bathe in it. I ran the EA12 24/7 from then until I bought and
used an IC-735 in January 1987.

 It is a GEC Crystal Unit, 100 kHz, serial number 82690 and type JCF/193,
"Made in England", and it looks like it means business.

Ian, G4ICV, AB2GR
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