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Old January 29th 15, 01:05 AM posted to rec.radio.amateur.homebrew
Ralph Mowery Ralph Mowery is offline
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First recorded activity by RadioBanter: Jul 2006
Posts: 702
Default 10.7 IF/Detector


"nothermark" wrote in message
...

If you can find an old scanner that has a true descriminator output
instead
of the phase detector types, then it is easy. Hook a DC scope to that
point
and fine a transmitter that has 1 khz steps . Go up and down one 1 khz at
a
time and see where the trace goes. At each point will be the 1 khz steps.

Hmmm, had not thought about that as I am also looking for a deal on a
signal generator. Come to think of it a 1 KHz shift between the
receiver and a transmitter will look like 1 Khz of deviation....


I have done that many years ago when I could not afford very good test
equipment. I did have a frequency counter that was halfway decent and an
inexpensive scope and multimeter. Had to learn how to do things to get by
with. Took a lot of time to do simple things, but I learned a lot in the
process.

Yes, if you have a true discriminator and a DC coupled scope the shift of an
unmodulated carrier will look like the deviation.