Model 65 Modulation Hum

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Model 65 Modulation Hum

Radioroslyn
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Posts: 7,286
Threads: 268
Joined: Dec 2009
City: Roslyn Pa

#10

10-21-2012, 01:52 PM

Something else came to mind if you still can't find it check your RF coils for (green primaries) corrosion. You may have a sightly bad coil that isn't giving you a good ground return for the grid of the tube. Also you could have a bad 24 tube. It could have a short from the cathode to grid 1 or a heater to cathode. If you've got a spare I'd swap it and see if that does the trick. Either 24 could be at fault. The pilot lamp may affect the overall amount of hum. It may have a bit more of less with or without it in the circuit.
Just a thought.
GL
Terry

(This post was last modified: 10-21-2012, 02:03 PM by Radioroslyn.)

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Messages In This Thread

Model 65 Modulation Hum - by Sourbone - 10-20-2012, 03:00 PM

RE: Model 65 Modulation Hum - by TA Forbes - 10-20-2012, 03:53 PM

RE: Model 65 Modulation Hum - by Sourbone - 10-20-2012, 04:17 PM

RE: Model 65 Modulation Hum - by LASJayhawk - 10-20-2012, 05:33 PM

RE: Model 65 Modulation Hum - by Sourbone - 10-20-2012, 05:53 PM

RE: Model 65 Modulation Hum - by 7estatdef - 10-20-2012, 07:00 PM

RE: Model 65 Modulation Hum - by Chuck Schwark - 10-20-2012, 10:30 PM

RE: Model 65 Modulation Hum - by Sourbone - 10-21-2012, 08:52 AM

RE: Model 65 Modulation Hum - by codefox1 - 10-21-2012, 10:06 AM

RE: Model 65 Modulation Hum - by 7estatdef - 10-21-2012, 01:52 PM

RE: Model 65 Modulation Hum - by peteivan - 11-02-2012, 09:29 PM

RE: Model 65 Modulation Hum - by codefox1 - 11-02-2012, 09:39 PM

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