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Old April 7th 07, 05:16 AM posted to rec.radio.amateur.boatanchors
Scott Dorsey Scott Dorsey is offline
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First recorded activity by RadioBanter: Jul 2006
Posts: 774
Default Crystal tester circuit using a 6C4 and would work with anything,where to find?

robert casey wrote:
Many years ago my father (now a silent key) built a crystal tester that
pretty much worked with any crystal you stuck into it. Low frequency,
high frequency, name it. It also had a meter that indicated "crystal
activity" and also had an adjustment (think it was a pot) for IIRC
"bias". Also an output jack to feed say a frequency counter.

I imagine that he got the circuit from either an issue of QST or the
handbook. Searched the web, though I found many circuits, none looked
like this one. Anyone recognize from my sketchy description the circuit
my father used, and any links to where I can get a schematic so I can
build my own? TIA


Pierce oscillator circuit will do what you want, and you should
find it in some editions of the Handbook. I know Hints and Kinks had
an updated version using a MOSFET, but to be honest anything with a high
impedance input and some gain will oscillate that way.
--scott
--
"C'est un Nagra. C'est suisse, et tres, tres precis."