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 jonah177

Tue, 17/01/06@22:29

Hello
We recently installed some logitech 5.1 speakers on our dell, but the computer is now talking to us! It's a foreign language, and seems to fade in/out when you adjust the volume. We are on broadband, but don't have the internet open all day. Are we picking up a radio station? We didn't notice it happening with the old pc speakers. Can anyone help?
Thanks

 woodchip

Tue, 17/01/06@22:42

Something connected or in the Computer is picking up Radio Frequencies. It is some sort of coil that does this, that the coils turns coincide with a Chanel. May be a Mic etc. The Speakers only amplify what the sound card is picking up

 jonah177

Tue, 17/01/06@22:58

speakers picking up radio

hi woodchip
thanks for your reply. we do have a mic plugged in the front. if you know how to stop it please let me know. i'll try unplugging the mic.
many thanks

 woodchip

Tue, 17/01/06@23:04

If it is the Mic you can only try a different one.

 rmcqua

Tue, 17/01/06@23:06

jonah177
Try getting hold of some ferrite rings (local Maplin electronics or other component store) and install them over the speaker leads as close to the PC as possible. If you can't get rings, small ferrite rods weill do with the wires wrapped around them a few times. That might fix it (prevents any RF which is being picked up by the speaker wiring from being fed through to the amp and being amplified there). You may need some rings at the speaker end of the wires too.

 woodchip

Tue, 17/01/06@23:13

They are no good on speakers, Read as above. once it's got into the sound card it amplifys it you have to stop it before it gets to the sound card.

 jonah177

Wed, 18/01/06@00:02

thanks for all the feedback. will try the route of the mic. wish i was techno minded like you guys!

Helen

 ashdav

Wed, 18/01/06@00:13

jonah177

Sounds like you are picking up shortwave or mediumwave broadcasts.
Try wrapping the mic lead a few turns around a big nail (I know it sounds daft).
If this doesn't work email me and I'll send you something which should cure it.

 octal

Wed, 18/01/06@07:16

Process of elimination

I take it your logitech 5.1 speakers are self powered? In other words they have an adaptor that plugs in the mains? If they are try the following:

Disconnect the speakers from the computer, plug the adaptor in and see if you can hear the voices.

If this is OK, remove all peripherals from the sound card like microphones, headsets etc, leave the computer off and plug the speakers back into the sound card and switch the speakers on, again check for voices.

If no voices are heard, now switch the computer on, check for voices.

If none are heard, start plugging peripherals back into the computer one at a time, all the time listening for those voices.

At any stage trying the above and you hear the voices come back and tell us.

One last question, what part of the country do you live in? The reason I ask is if you live around Ludlow you are close to the high power shortwave transmitters at Woofferton, if you live in the east Essex/Suffolk area you are close to the high power medium wave BBC world service transmitter at Orfordness, so you maybe picking up their transmitters.

 rmcqua

Wed, 18/01/06@08:55

woodchip:
The source of the RF may be the speaker leads. Mic leads don't usually pick up RF because they are screened, whereas speaker leads are not.
I believe it's worth a try.

 jonah177

Wed, 18/01/06@15:27

I think I may be busy this weekend playing with pc wires!!
I will try a proccess of elimination (or more likely the other half will!)
We live in the Medway area (southeast)so I don't know if there are transmitters around here. Funny we never heard it with the old pc speakers.
Allelujah for forums, you get a lot more help than going down your local pc superstore!!!

 rmcqua

Wed, 18/01/06@15:42

Good luck jonah177
I used to be an active radio amateur and wish I had a £ for every hour I spent trying to fix radio frequency interference (RFI) to neighbours' A/V equipment! (I once had the dubious privelege of being "heard" on the local church organ)>

 Diemmess

Wed, 18/01/06@15:51

Just to throw some mud into the water.
Time was when amateurs built talking type radios and amplifiers, a "dry" joint or dubious resistor behaved like the 1920s cat's whisker, rectified an incoming signal picked up by an audio lead somewhere which itself was forming a crude tuned circuit.

Local radio and some of the press still love to report someone claiming that she can hear Radio 2 on her false teeth! That is almost certaily a flawed casting of a chrome cobalt partial denture with tiny oxide inclusions.

Your problem is unlikely to be caused by duff manufacture, but Octal suggests a good way of finding where the problem lies by elimination.

 octal

Wed, 18/01/06@18:08

Diemmess

"Time was when amateurs built talking type radios and amplifiers, a "dry" joint or dubious resistor behaved like the 1920s cat's whisker, rectified an incoming signal picked up by an audio lead somewhere which itself was forming a crude tuned circuit."

The cat's whisker is a rudimentary form of diode which nowadays have turned into transistors, of course computers are full of 'em.

jonah177, to answer your question about the reason why you didn't hear it on your old speakers. It all boils down to susceptibility, some items of equipment are more susceptible to the pick up problem than others. If you are living in the Meadway area you will get very strong signals from the BBC world service transmitter at Orfordness near Woodbridge in Suffolk, also there are some very powerful transmitters in the Netherlands and Belgium, all which are over a sea path, so if your equipment is susceptible, you will pick them up.

Let us know how you get on and good luck.

 jonah177

Sun, 29/01/06@23:34

hi again
so far we have unplugged the mic and moved the base speaker away from the pc a little. We haven't noticed the sounds since, but somehow I feel we will still need to try some more of your tips to solve the problem - I think it is more a case of not noticing it than it gone away!
Thanks to everyone for your suggestions. On another note we get little pops through the speakers when we turn lights on or off etc - I guess this is all part of the problem, but if anyone know of a different reason for this please let me know.
Many thanks all.

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