That sounds like the creators of your TV did not use proper grounding
technics. Take the back cover off and check out the ground wires that tie
the shields together. Make it short as possible and put a large ferrite on
the wires to the tube. I used this to fix a few monitors from Samsung
during the 96 CE Mark madhouse. The frequency range I tested was from 26MHz
to 1000GHz at 3V/m CW with 80% AM 1kHz.
(Embedded image moved to file: pic01869.gif)
"Bob Tellefsen"
<n6wg@earthlink.n To: "N6KJ"
<kelly@thejohnsons.ws>, <rfi@contesting.com>
et> cc:
Sent by: Subject: RE: [RFI] Tough to
solve TVI problem
rfi-bounces@conte
sting.com
06/05/2003 07:29
PM
Kelly
You didn't say outright, but it sounds like you are feeding
your antennas with coax.
1. Do you have a balun at the antenna? If not, can you add one
easily?
2. Can you feed the antenna with 300 ohm twinlead as a
balanced-line experiment? I ask because I cleared my TVI years
ago by going to a totally balanced antenna system.
Hope this gives you an idea or two.
73, Bob N6WG
-----Original Message-----
From: rfi-bounces@contesting.com [mailto:rfi-bounces@contesting.com]On
Behalf Of N6KJ
Sent: Thursday, June 05, 2003 5:14 PM
To: rfi@contesting.com
Subject: [RFI] Tough to solve TVI problem
I have a 10 year old Mitsubishi 35" CRT TV, model number CS-35201.
I am getting TVI on both 40 and 80 meters. Both dipoles are about 30 feet
above the TV. On 40 meters, I get interference with as little as 5 watts
TX output. On 80 meters, I get interference with as little as about 20
watts.
The rig is clean and has a low pass filter on the output. The TV has an AC
line filter and ferrite beads on all inputs. I get interference on all
channels regardless of input source (satellite rcvr, DVD, VCR) or input
jack (S-Video or 75 ohm rf input). Normally, I only use the S-Video input.
I have tried grounding the rig to an 8 ft. long ground rod and leaving it
floating and there's no change. The rig should be clean. It is an
FT-1000MP and just came back from Yaesu service with a clean bill of
heatlh.
As best I can tell, the interference is
coming right through the chassis and getting into the video circuitry.
Does anyone know of any particular issues with Mitsubishi or this
particular
model? Any suggestions of what to try next? I can't even get a service
technician to work on this. I've called several service technicians and
they
insist there's nothing they can do about it. Mitsubish won't acknowledge
that
it could be a TV problem either.
Has anyone found a TV manufacturer that manufacturers "clean" tv's and/or
understands these types of issues? I'll make a more informed choice next
time around :-)
_______________________________________________
RFI mailing list
RFI@contesting.com
http://lists.contesting.com/mailman/listinfo/rfi
_______________________________________________
RFI mailing list
RFI@contesting.com
http://lists.contesting.com/mailman/listinfo/rfi
|