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No AVC?
1/26/1999 7:37:56 PMStephen Smith
As you have probably guessed I'm really getting into this and have more questions then answers. Recently I've been playing with a Crosley 519 and a Philco 46?-200.
I have a 1629, "EYE" tube that I wanted to use as a tuning indicator. I was able to find the AVC on the Philco and with a little jury rigging was able to make it work. I then turned my attention to the Philco and can't find anything that looks like and AVC line. It's probably right in front of me. The Philco uses a 50L6GT, 35Z5GT, 7A8, 7B7 and 7C6. Is it possible that this radio doesn't use an AVC signal?
1/26/1999 10:39:22 PMNorm Leal
: As you have probably guessed I'm really getting into this and have more questions then answers. Recently I've been playing with a Crosley 519 and a Philco 46?-200.
: I have a 1629, "EYE" tube that I wanted to use as a tuning indicator. I was able to find the AVC on the Philco and with a little jury rigging was able to make it work. I then turned my attention to the Philco and can't find anything that looks like and AVC line. It's probably right in front of me. The Philco uses a 50L6GT, 35Z5GT, 7A8, 7B7 and 7C6. Is it possible that this radio doesn't use an AVC signal?

Hi Stephen

A radio with those tubes will have AVC. The AVC voltage will be generated by a diode in the 7C6. You should be able to find this AVC voltage on the signal side of the volume control. From there it goes through a large value resistor, 1 meg or more, and to a cap to ground. (.05-.1mfd) If you just can't find the AVC voltage this cap may be shorted. I would expect an AVC voltage of -10 volts or more on strong stations.

By the way, you know how to get the 12 volts for filament of the 1629? You can use a voltage doubler right off of the 6 volts.

Norm



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