Hey guys,

My computer speakers are picking up and amplifying a specific FM radio signal. I have noticed that it gets somewhat louder when other things get plugged in to the same surge protector. Does anyone know how to fix this?

 

Hello,

Are you shure it is an FM radio station?
A FM signal needs a fm-disciminator to be heard.
An AM signal can be detected by the base/emitor-diode of a transistor, and more often heard in audio devices.

On this website there is a possible solution :
http://www.stevelarkins.freeuk.com/computer_interference.htm

Greetings,
Bertus

 

Hello,

Are you shure it is an FM radio station?
A FM signal needs a fm-disciminator to be heard.
An AM signal can be detected by the base/emitor-diode of a transistor, and more often heard in audio devices.

On this website there is a possible solution :
http://www.stevelarkins.freeuk.com/computer_interference.htm

Greetings,
Bertus

Yep...almost absolutely, positively an A.M. station. Having been chief engineer of a 50KW station for a quarter century, I learned how to get R.F. out of every device known to man.

Ferrite beads around the speaker leads are the best first line of defense. They will solve about 90% of overload problems like this.

eric

 

Hey guys, thanks for the info so far. I just want to confirm that I am in fact picking up an FM signal. I verified this using a clock radio I have in my room. Can I still use ferrite beads or would something else be better? Thanks.

 

Make certain you are using a shielded audio input cable, not an unshielded headphones extension cord.

 

Along with using shielded cable, make sure that your speaker connections are clean. 91% isopropyl alcohol on a small cotton swab used on the jack and plug may help.

Make sure your power connections are clean.

Try swapping out your surge protector with a new one. If it's been in use for awhile, it's likely that it either has corroded sockets and/or it's been subjected to the effects of a lightning strike. If a lightning strike was nearby, the MOV(s) inside the protector could be fried and you wouldn't know it.

 

Wow it's pretty much completely gone now, that was it. I still hear it but its very faint, I'm going to try the ferrite beads to get rid of all the interference. Thanks.

 

Wow it's pretty much completely gone now, that was it.

What was it?

 

Make certain you are using a shielded audio input cable, not an unshielded headphones extension cord.

This got rid of pretty much all the interference. I'll try the other suggestions too. Thanks guys.

 

I've also had problems with that in the past. My house is a few hundred feet from a radio tower. Everything in our house used to be able to pick up FM 101.9 (our local station). They moved to another town though, so no more problems.