Some early commercial broadcast FM transmitters used very low
fundamental crystal frequencies; the large frequency mulitplication
was needed to produce the relatively wide FM deviation.

Pete

"Frank Dresser" wrote in message
...
I have 112.30 kc crystal and I'm curious about what it was originally used
for and what sort of equiptment it was used in. It's in a metal can, like
a
short version of a 6L6, with an octal base. It's marked GENERAL ELECTRIC
as well as with the frequency and several other numbers.

I'm vaguely aware that this band is used for some sort of maratime
purpose,
but I don't know exactly what.

I hooked it to an audio generator and a scope, and it's series resonant at
more or less the marked frequency.

Frank Dresser