Hi The “small” (less than a pound) 100 KHz crystals are not really great in terms of performance. If you get a GT (big thin square plate with attach right in the middle) they can have ok temperature performance. Because of their small size, their Q is relatively low and thus things like phase noise and ADEV are not very good.
Not accurate, but at least a hand waving sort of number: If a high Q 5 MHz is 0.5” diameter *and* you did the same design at 100 KHz, it’s going to be 25” in diameter. (Obviously not the way to do it). Bob > On Jun 4, 2016, at 12:59 AM, Ian Stirling <i...@opus131.com> wrote: > > 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 > -- > > _______________________________________________ > time-nuts mailing list -- time-nuts@febo.com > To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts > and follow the instructions there. _______________________________________________ time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there.