Strange AM radio static noise

Possiblbly a bad CFL lamp somewhere. With the cold weather, CFL's do strange things.

Cheers

Bad electrical connection / wire nut joint, somewhere upstream from the closet light... loading the connection apparently is enough to stop its intermittent connection and arcing.

This is serious, you could have a potential electrical fire in the making. Maybe call in an electrician? ...Jim Thompson

Thanks for the tip. I was thinking it was due to some bad ground connection maybe.

Any poor connection can make minute arcing. You notice it at night on AM stations since most of them must reduce transmitted power at (local) sundown., so your radio AGC's gain goes up to compensate, making it also more sensitive to electrical "static". ...Jim Thompson

I experienced a similar situation several years ago. It turned out that one of the lighting circuit breakers in my service entrance was causing the noise. Simply opening then closing said breaker solved the problem. There were no active loads on that circuit. Go figure.

I bet it's a touch light switch ?

Jamie

You said "vitually disappears". Does that mean that it's still somewhat audible when the light is turned off?

Check the following with a portable AM radio for EMI:

1. CFL lights
2. LED lights
3. Light dimmers
4. Arcing connections
5. Arcing conventional wall switch
6. Arcing circuit breaker
7. Alien invaders

However, if it doesn't completely go away when the power it turned off, I would go hunting for switching type wall warts (power supplies and chargers). The Chinese cheap clone variety produce large amounts of RF noise. Almost anything with a switching power supply inside (which is just about anything electronic these days) should be tested.

Also, to be sure that it's actually coming from your house, turn off the power to the entire house at the breaker panel. If the noise is still there, then it's coming from the neighbors (or the alien invaders).

You might try a small portable AM radio to sniff around and locate high noi se places. I have the same problem and traced it to my desktop computer whi ch was turned off. Don't know what's wrong with it, but the noise goes away when I disconnect the power plug. It doesn't have a hard power switch, so I have to pull the power plug out of the computer.

-Bill

If the noise is worse with it off suspect the switch itself.

Try unscrewing the lamp from the socket and see what happens. Keep us "posted".

If it's broadband, moving up in frequency more easily locates source. Shortwave, cb, am detection.

Greg

I have the same problem and traced it to my desktop computer

Many desktop computers stay partially on all the time, so that they can do "wakeup from LAN", ie. turn on when a message comes in to the Ethernet port. Some have a yellow LED on the motherboard that stays lit to indicate standby power is on. The network jack lights may still light up, too.

Jon

The problem is gone now. It appears that one of those in-line switches of a nearby lamp was responsible. It provided marginal connection when it was switched on.