radio station????

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mcsparky

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Hi all....newbe here and was just wondering if anybody else has had this bizzar thing happen to them.

Low down on the install is

Cooper (menvier) security M800 control panel with 4 remote keypads and 4 extension speakers. Its a large domestic install with 32 zones and 3 external sounders. Just bells only at the moment.

The problem is really bizzar.....all extension speakers are fine except for the landing speaker which has radio interference coming through it. When i say radio interference, i mean radio interference..........music and voices talking!!!! Now the thing is that all speakers are fed from thier respective remote keypad outputs....EXCEPT for the landing one which is the speaker in question. The landing speaker is fed from the control panel. I have walked around the house today and checked that all tv's and radio's are switched off at the mains socket (not just standby) but that didnt work. The nearest neibour is a good 400/500 meters away so would'nt expect it to come from there either.

Any help on this would be great

Thanks people and happy scratching? :|

 

The Godfather

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May I ask..

The location, and how far is the local TX for Radio & TV?

The reason I ask is because in strong signal areas of the above mentioned, is that the signals 'are' picked up by wiring and demodulated (crudely) by various means.

Hence the music.

The Godfather

 

springcrocus

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As the Don said, the speaker wires are probably acting as a dipole aerial. Try placing a ferrite choke around the cable near to the speaker end of the wire.

These are examples of ferrite chokes

 
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Welcome mcsparky.

As the others say.. Radio interference from your nearest transmitter...

Nothing to do with TV/Radios on in the property or adjoining properties.

Some part of the electronics in the control panel is creating a tuned circuit which matches one of the frequencies the particular radio station you can hear on the speaker.

This phenomena can also be experienced with some modern electronic land-line telephones, once the first digit is pressed, if you listen before dialling more digits, you no longer hear dial tone but you can hear a faint radio.

especially when the phone wire comes overhead, nice big aerial sticking out the house.

I guess some part of you speaker wire is very nicely positioned to act as ariel and the control panel and loudspeaker makes a basic little crystal set tuned for just one radio station.

I would agree with SpringCrocus get your ferrets out, ooops FERRITE'S!!! :D

Or possibly run the speaker wire in a screened cable may do the trick?

Your location says Solihull, so at my guesswork the Big transmitters nearest to you are Sutton Coldfield & Droitwich.

BUT as a minor bit of trivia I understand one of the functions of Droitwich transmitter is to do Long Waves radio signals...

Which go all the way down to Lands-End!!

So if its long-wave you are picking up...

You ain't going to get away from it!! :_| :|

just need to reduce it or suppresses it in some manner.

SL. :)

 

springcrocus

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Try turning the house through 90 degrees (Can't find a symbol for degrees:()

 

Admin 2

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Still dont work.

When i hold in Alt and start pressing any numbers the cursor(think thats what its called) disappears and the page moves up????

altho when i press Alt Gr and number 4 i get

 

Admin 2

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Interesting Admin 2. Are you using a laptop? I posted earlier from the desktop @ work and that does it. I'm home now on laptop and that doesn't, unless I plug a seperate USB number pad I have in! Doesn't work with the numbers at the top of the laptop keyboard. Curious
No not using a lappy.

Wonder if it will work on firefox? or has that got nothing to do with it?

 
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