J=F3n-

The Cat-5 cable is twisted and therefore cancels=20
magnetically-induced noise (one twist acts like a=20
small inductive loop, but then the next twist=20
detects the fields backward and cancels the=20
noise). RCA-type of shielded cable is designed to=20
shield higher frequencys (up in the audio range)=20
and magnetic fields can easily penetrate the=20
shield. Also the shield is usually woven or worse=20
yet just wrapped around and is not a 100%=20
covering. CAT-5 is a better choice, but some=20
phone wire is twisted also and will work (in the=20
States, the phone wire from the wall to the phone=20
is usually parallel, but the wire in the walls is=20
usually twisted). Some instrumentation wire is=20
the best of both and has twisted wire inside a=20
shield (if you use this, tie one wire and the=20
shield to ground AT ONE END ONLY).

Hope this helps

At 05:09 PM 5/12/2010, J=F3n Fr=EDmann wrote:
>Hi all,
>
>I did replace my cable the other day from Cat-5 shielded cable to a RCA
>cable that is also shielded. But with the Cat-5 cable I did not get
>electronic noise. But with the RCA cable I do. I rather do not want to
>switch back to the Cat-5 cable, as it is harder to manage.
>
>What might be the reason why I am seeing electronic noise on the RCA
>cable ?
>
>Regards,
>--
>J=F3n Fr=EDmann J=F3nsson
>
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George=20

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