181115-1216 EST
nizak:
Yes.
Your circuits are not separate from the perspective of noise. Everything is tied together at the main panel.
Phase shift dimmers, even on incandescents, are a noise source. This is from the very high rate of change of voltage at the switching point in every half cycle.
I have some 9.5 W LEDs from Home Depot that oscillate right around 1 MHz, middle of the AM band, when AC voltage is above about 112 V. My next door neighbor and I are the only ones on a 50 kVA pole transformer, and two street lights. One of said bulbs produces enough noise energy that I need to get more than about 75 ft beyond the street light before my car radio is free of the interference. I don't normally drive in the opposite direction and therefore I don't know if much of this energy passes thru the pole transformer.
Separately I have a Costco 4' LED shop light that produces so much noise that it interferes with low voltage measurements on my oscilloscope. I have to turn the light off and use an incandescent.
For at least 60 years I have used 8' Slimline fluorescent lights. I always installed a Corcom noise filter inside each fixture to reduce RF noise output.
Different LEDs have different noise outputs. So changing bulbs or fixtures can move the noise generated to some other frequency range that may be less of a problem. Other bulbs I have tested were in the 50 kHz range.
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