Philco 84 now has a hum - Printable Version

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+--- Thread: Philco 84 now has a hum (/showthread.php?tid=15956)

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RE: Philco 84 now has a hum - morzh - 12-26-2016

Speaking of FCC part 15 subpart B conformance for Unintentional Radiators.

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RE: Philco 84 now has a hum - Radioroslyn - 12-26-2016

Hey Mike,
I've got a similar issue w/my fairly new refrigerator. When the compressor kicks on the line noise triples. Very annoying!!! At first I thought it was a switch mode p/s some where in the house but tracked it to the fridge. Haven't tried to fix it yet but is on my long to do list.

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RE: Philco 84 now has a hum - morzh - 12-26-2016

Terry

It is strange, the asynchronous motors are not known to be big offenders.
You could try to buy/build a large enough filter and plug through it.
You could start with a few microfarads of capacitance in parallel to the lines. I doubt Y-caps would do much, the noise is likely the differential one.

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RE: Philco 84 now has a hum - Radioroslyn - 12-28-2016

So if I hook this puppy across the line all the noise will go away, neighbors will thank me for cleaning the line for blocks and blocks???

or

Will I be cursed for years for make the hood go black??

Don't know how many nf it is but it's 12mfd @ 3500v np.

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RE: Philco 84 now has a hum - morzh - 12-28-2016

The hood won't go black as 12uF is not that much of a capacitance and is an equivalent of 220 Ohms load except it is purely capacitive, and the current itself will be 1/2 A.
And this is one of those cases where "the size doesn't matter"

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RE: Philco 84 now has a hum - Radioroslyn - 12-28-2016

(12-28-2016, 05:44 PM)morzh Wrote:  The hood won't go black as 12uF is not that much of a capacitance and is an equivalent of 220 Ohms load except it is purely capacitive, and the current itself will be 1/2 A.
And this is one of those cases where "the size doesn't matter"

So abt 50wts.
Do thing improve if I add a few hnys in series with the cap?? I may have a 5 or 600 ma choke around.

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RE: Philco 84 now has a hum - morzh - 12-29-2016

I don't see why unless you are having problems. Yes LC filters are good if used correctly. Henries? Depends what noise it is.

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