Jim Brown wrote:
>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
Jim,
I may be barking up the wrong tree, however let me explain my reasoning. If
you would re-read Toni's original post,
.I Quote:
>I narrowed it down to
>there jumpers from the tv to the dvd which are not
>shielded.
Toni stated that he had isolated the problem to the Un-shielded cables
between the DVD player and the TV. I was addressing that statement.
I agree with your statement that Speaker cables are a real source of
interference, However Toni did not reveal that an amplifier or external
speakers were in use. That should not be a problem with built in speakers
inside the TV.
* 73's Jim W5IFP *
>-----Original Message-----
>From: towertalk-bounces@contesting.com
>[mailto:towertalk-bounces@contesting.com]On Behalf Of Jim Brown
>Sent: Sunday, December 28, 2008 9:04 PM
>To: Tower
>Subject: Re: [TowerTalk] RFI WITH MY NEIGHBOR...HELP!
>
>
>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
>No virus found in this incoming message.
>Checked by AVG - http://www.avg.com
>Version: 8.0.176 / Virus Database: 270.10.1/1867 - Release
>Date: 12/28/2008 2:23 PM
>
_______________________________________________
_______________________________________________
TowerTalk mailing list
TowerTalk@contesting.com
http://lists.contesting.com/mailman/listinfo/towertalk
|