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Philco 42-380 120 Hz Hum
#3

I do have quite a few switching converters at home.  As a SWL enthusiast, I have tested most of them and replaced the small handful that have noticeable EMI issues.  However, your point is well taken as they are constantly being added whenever a new appliance is purchased so it would be easy for me to miss one.  I just tuned my Icom to the AM broadcast band and I do in fact hear a fair bit of what I would describe as shot/ignition noise there, which diminishes at higher frequencies.  The main difference in behavior between it and the 42-380 is that when I tune in a reasonably strong AM station on the Icom the noise disappears.  Not so on the 42-380 where the 120 Hz hum remains quite audible on most, but not all stations.  As far as CCFLs go, I can't be certain but I think most of the displays in the house (TVs, computer displays) are LED backlit.  It would be an interesting experiment to selectively power off each circuit in the house while listening to the 42-380 or Icom to see if that might locate the source of the problem.  I will add that to my list of things to try.

--
Jason


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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