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Philco 42-380 120 Hz Hum
#9

Audio amp - yes, detector - no. Then again, detector is rarely the problem, if ever.

Does gounding he chassis make any difference?

At any event, if you could by tracing (say by pulling one by one RF tubes before detector) see if the hum stops at wone point, then it is likely an interference. I saw several cases where a radio sounded fine before having been relocated, usually those were cases of electrical noise, in Mains or radiated by home dvices / Power lines.

Moving the radio inside the house could show difference, switching off lighting sources one by one. In my old house it was the fixture in the lobby. Sometimes the opposite is true: turning on some loads attenuates hum. Or maybe even binging it
back to the repair guy's house to see if the hum is there.

The other radio you have - is it a transistor? Or does t have a frame/loop/ferrite antenna? If yes, does rotating the radio around gets the hum to appear?

People who do not drink, do not smoke, do not eat red meat will one day feel really stupid lying there and dying from nothing.


Messages In This Thread
Philco 42-380 120 Hz Hum - by Jason63 - 12-27-2017, 05:31 PM
RE: Philco 42-380 120 Hz Hum - by morzh - 12-27-2017, 06:07 PM
RE: Philco 42-380 120 Hz Hum - by Jason63 - 12-27-2017, 08:38 PM
RE: Philco 42-380 120 Hz Hum - by Radioroslyn - 12-27-2017, 09:03 PM
RE: Philco 42-380 120 Hz Hum - by klondike98 - 12-27-2017, 10:12 PM
RE: Philco 42-380 120 Hz Hum - by Jason63 - 12-28-2017, 11:01 AM
RE: Philco 42-380 120 Hz Hum - by morzh - 12-28-2017, 12:47 PM
RE: Philco 42-380 120 Hz Hum - by Jason63 - 12-28-2017, 03:08 PM
RE: Philco 42-380 120 Hz Hum - by morzh - 12-28-2017, 03:31 PM
RE: Philco 42-380 120 Hz Hum - by Radioroslyn - 12-28-2017, 03:34 PM
RE: Philco 42-380 120 Hz Hum - by Jason63 - 12-29-2017, 06:55 PM



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