Philco model 18 (code 121) - HELP!
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City: Sedona, AZ/Placentia/CA
Sorry I confused you. I guess that is our job at some point.  My comment on modulation refers to the point that a signal generator of the type we use will add a frequency (audio) that you can hear at the speaker . So if your pumping in an IF frequency to align the IF section, it will carry some tone with it. This is typically 300 or 400 cycles, makes an annoying sound out of the speaker and you can hook you meter to the speaker coil and measure the A/C (low voltage) for peaking. Mine has only one frequency as do most. Yours has another input for putting in an alternate tone or music. Think of putting into that your i-pod and your signal generator becomes a radio transmitter! Dial your sig gen to the frequency of your radio is set your probe near the antenna input of your radio with a small loop of wire and you can become your own transmitter with any frequency adjustable to your radio.
If you didn't have a tone on adjusting the frequency for something like the IF alignment, well, you couldn't hear it or monitor the AVC voltage or speaker, another way to peak. Your new one will work very well.
Just a nice little feature.
Jerry
A friend in need is a pest! Bill Slee ca 1970.
(This post was last modified: 02-12-2013, 05:48 PM by jerryhawthorne.)
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RE: Philco model 18 (code 121) - HELP! - by jerryhawthorne - 02-12-2013, 05:22 PM
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