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how to eliminate air-born RF

any ideas on how to eliminate airborn RF. I have disconnected all equipment from themselves and the ac outlet. Even shut off the main circuit breaker in the service panel. Have disconnected all video cabling and antenna wires. after all this, when I place my head behind my rack, which just holds my amps, I can here a humming noise similar to the ground like hum you hear from an electric guitar/amp combo or similar to a bad tonearm phono ground loop. With system wired up and operational, this humming is easily heard at idle on, with gain on preamp down. Again, this is occuring with nothing physical wired together or to the ac outlets and with all ac power shut off in the house. PLEASE HELP!!!
128x128mooncrikit
pmkalby
130 posts
 
Mooncrikit sent me the following via email:

I live in a single story family housein the suburbs on a 1/4 acre lot. I moved my amps and preamp and speakers and cd source to the other side of the house with no change. The only part of my gear that would be sucseptible to
microphonics would be the preamp, which is tubed, but I borrowed a buddies AR-LS1 and the same [stuff] was happening. I figure its RF since I shut down the main circuit breaker to the service panel, unplugged all gear from each otherand the wall and can still hear a humming onlt in this area of the house.

Well, I have no idea unless you live next to a giant power transformer and didn't tell us.
eldartford
4,262 posts
 
RF is not "air born" and you can't hear RF (even if you are a bat).

Find out where the noise is originating by using a cardboard tube (like the kind paper towels are wound on). Listen through the tube, and move it around until you find the source. Could it be insects (like crickets)?
mejames
986 posts
 
Call the people who investigate ufo sightings or the people who investigate haunted houses maybe they could help you.
edesilva
768 posts
 
Sounds like it might be 60 Hz hum from a transformer of some kind, but that only occurs if there is something powered up. Any chance you might have low voltage halogen lights on a different circuit breaker? If you still hear it and the whole house mains breaker is off, you may want to get your ears checked--might also be tinnitis...
philip_psha5b7
28 posts
 
Assuming that Edesilva might be on the right track about a very strong electromagnetic field (EMF)expanding and contracting at 60hz frequency from a rogue external power equipment, your speaker cables can pick up that like a wire-loop induction. If your speakers are efficient enough it might be playing the hum all day long without your amp turnon. I can be wrong, but try disconnect your speaker cables and see if the hum is still playing.

I do hope I'm wrong in this intriguing Mooncrikit case. There were many health concerns raised by people who live near sources of EMF recorded by Mark A. Pinsky in his book "The EMF Book" 1995 Warner.
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