"One thing you should realize about line filters is they are optimized for
conducted line emissions coming from the product where they are built in."
That could explain some things. A few months ago I posted details of tests
using various common filters such as we find online and in scrapped
electronics with rating from around one amp to around 15.
The test was simple, a 100W "equivalent" LED light bulb that generated X
amount of RFI on HF. Using a portable radio, I swept the light bulb and the
6' cord feeding it listening for noise. RFI was found at the bulb, as
expected and a smaller amount, I think around 6 to 12 inches from the bulb
with little to none along the rest of the cord.
I added various filters at the base of the bulb to see how they would
prevent RFI from traveling down and radiating from the line cord.
The results were disastrous! Massive amounts of RFI blasted from every inch
of the cord and most of the wiring in the shop where none had existed before
regardless of the filters used. I asked on this list how this could be. No
response.
Kurt
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