This is a very interesting discussion. I have experimented with some audio frequency crystals in the 3-6 kHz range. I don't know what they came out of but it was probably some sort of FDM telephony or telegraphy equipment. They're in the form of vacuum mounted bars with 4 plated terminals in tall 7 pin or octal tube envelopes. When suitably driven they oscillate audibly like a bell ringing and as a result of the very high Q they even keep ringing for a few seconds after the power is turned off. Unfortunately I don't have access to a stroboscope. I'd like to do something useful with them on display, perhaps a clock for people with presbyacusis who wouldn't notice the sound :-)
Morris >> You have it right, iovane. At the least, they should be protected >> from light, >> thermal radiation, and emf. Won'drous things will happen if the >> crystal and >> its structure are subjected to radiation through the glass. I'd >> suggest a foam gator wrap in a tin can as a minimum. Put the >> oscillator cat in there too. > > I have a 100 kHz glass "Crystal Unit" made by G.E.C., type JCF/193 > with a serial number and sealed in a valve/tube with seven pins. > I removed it from my Eddystone EA12 that I bought from Tom Roberts, > G3YTO, SK 1985. It has a black shield with a spring inside at the top > so that it grips the base. The valve that produced 100 kHz markers for > dial calibration failed and I don't use the EA12 these days. > It will be interesting to see how stable it is and what the effect of > light and heat on it is when I start experimenting. _______________________________________________ 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.
