Hi all I have a set of 5.1 Logitech speakers and since I have had them they keep picking up some forign radio station if I turn the volume down as soon as I turn them up I loose the station very wierd.
Rf can be picked up from the input leads or the speaker leads. You might try to figure out what the point of entry is.
If these are powered speakers then there should be an RF filter at the input of the amplifier. It's possible that's missing. If it's the speaker wires, I would expect that changing the cable orientation especially from horizontal to vertical would make a big difference since FM stations are usually polarized in one direction and I think that's horizontal.
You probably live near a small radio transmitter or maybe someone has an FM transmitter at home.
Ferrite beads, such as this one: **broken link removed** can be wrapped around the speaker cable or the audio cable.
Is the audio cable used, shielded?
Have to consulted the manufacturer?
Is this a powered speaker?
Can you post a pic of the speakers, showing the leads?
I dont think the cable is sheilded there molded cables that come from the back of the sub woofer.
I had this issue in my last house to about 0.4 miles down the road from where i am now so not that far but still it must be a good radio station I am picking up all so the language spoken sounds french not that makes any diff but still LOL
Move the wires around, you might be able to get it to stop, or put some clamp on ferrite rings on all the wires to the amplified speaker.
When I was a kid I was fascinated at a piezo earphone that came with a radio I had, at night it would play red rose radio quite merrily even though it wasnt plugged into anything.
Move the wires around, you might be able to get it to stop, or put some clamp on ferrite rings on all the wires to the amplified speaker.
When I was a kid I was fascinated at a piezo earphone that came with a radio I had, at night it would play red rose radio quite merrily even though it wasnt plugged into anything.
Before you go to the trouble and expense of ferrite rings, can I suggest that you try putting 1000pF capacitors across the input to the amplifier, connect them as close to the first stage of the amplifier as you can conveniently get to.
May be also worth doing it on the amplifier outputs to the speakers as well.
Try changing the input cable as a test. A cold solder joint on a length of wire can have a crystal of tin or even flux that will demodulate AM. I heard part of a baseball game on a microphone cable once, then I reflowed the solder joints on the connectors (I don't like baseball).
I wouldn't worry about the polarisation of the signal. That only applies in free space. by the time your wires are picking it up it will have been battered around and repolarised due to reflections.
Winding your cables around a 6 inch steel nail will probably sort it out. Cheaper than ferrites and at audio frequencies will not affect the sound.