The On Sun, 28 Dec 2008 20:39:43 -0000, Jim Hargrave wrote:
>Tony,
>I would first replace the DVD cable with one that each line has individual
>shields. You might want to go with individual cables. Normally single cables
>are shielded. If you have a three wire Siamese cable, I'm surprised it would
>not be shielded.
You would be barking up the wrong tree! This is not a shielding problem, it
is likely to be a pin 1 problem. One or more cables in the neighbor's system
is acting as a receive antenna and coupling your RF into some part of the
audio system that is detecting it. The most practical solution is usually to
block the antenna current with a common mode choke, or to divert it away from
the entertainment system.
The other VERY common coupling mode is the loudspeaker wiring, which couples
RF into the output stage. All output stages use negative feedback to reduce
distortion and noise. Any RF present on the output wiring is coupled by that
feedback network back to the input, where it is detected. This coupling can
also be fixed with a common mode choke. It can also usually be fixed by
replacing parallel wire speaker cable (glorified zip cord) with twisted pair.
See http://audiosystemsgroup.com/RFI-Ham.pdf for more detailed explanation and
advice on this.
73,
Jim Brown K9YC
_______________________________________________
_______________________________________________
TowerTalk mailing list
TowerTalk@contesting.com
http://lists.contesting.com/mailman/listinfo/towertalk
|