Since most surviving Chevy Vega's now have big-block V8-s in them that's
probably not a valid analogy ;-).

"-Bill M-" exray@coquidotnet wrote in message
...
Edward Knobloch wrote:
I would simply use a divide by ten oscilloscope probe
connected to the plate of the S-108 local oscillator tube, feeding
a frequency counter. The divide by ten probe provides isolation,
to avoid pulling the oscillator off frequency.

If you just want a 100 KHz calibrator, I recommend an old Bud Radio
model "FCC-90 B". It has it's own power supply, and requires
no connection to the receiver. (Just uses a loosely coupled
antenna wire near the receiver input). It has two tubes,
a 35W4 and a 50C5, in a transformerless circuit.
The older Bud model FCC-90 used octal tubes.

73,
Ed Knobloch

While all of the previous comments are good advice I suspect a counter
would drive a guy crazy on an S-108 with the constantly drifting freq
and oscillator pulling.
The 100kc calibrator will get you in the ballpark...at least to as close
as you can read the dial...I don't recall that there's a front panel
tweak to align the pointer or LO to have the calibrator line up with the
dial.
Nice little radio but if you want a better radio, well...
Its kinda like sticking STP racing stickers on a Chevy Vega.

-Bill

Let the newsgroup scroll proclaim that -Bill M- exray@coquidotnet scribed
upon its pages in :


Nice little radio but if you want a better radio, well...
Its kinda like sticking STP racing stickers on a Chevy Vega.

-Bill


So, who told you about my Vega? G

--
Allen McBroom
www.NPSTKD.com
Remove WOOF when replying by email

Allen McBroom wrote:

I've had an old Hallicrafter's S-108 since the early 70's, and trying
to tell what freq I'm on is impossible. Does anyone know of a method for
installing a crystal oscillator on this old tube rcvr, or some other method
of acurately determining which frequency the radio is receiving at the
moment?
Many thanks for the help!

How about getting a digital frequency display for the S-108. I use one
with several of my boatanchors. Here's a website that makes digital
display kits for shortwave receivers:

http://www.aade.com/dfd.htm


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