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TV Interference/RF Noise???

Hello, I have a problem with my TV. I recently hooked up my DVD to my new TV with component video cables and when the DVD is powered up I can see a "ghost" image of local TV stations floating across the screen. I have tried using two different "double shielded" component cables and it still occurs. I also tried both component inputs on the TV and the result was the same. I live in the city and I believe I am the victim of too much "broadcast noise" in my area (I'm in line of sight to the Sears Tower which has huge broadcast antennas on the roof). There also is an audible buzzing sound from the TV speakers. I originally thought this was a ground loop problem (the TV and DVD have no third ground prong on their plugs), but I have tried removing all other components from my AC outlets and I have also grounded my coax cable shield to my AC ground (this solved an earlier problem with my audio speaks buzzing when my amp was powered up). In fact the TV speakers still buzz when the coax is not connected to the TV at all and when I walk around to the back of the TV I can make the buzzing louder/quieter simply by being next to the rear of the TV. I have tried another TV in the same location and the speaker buzzing is still present. This leads me to believe that I'm picking up interference from the "airwaves" and it does not affect my HiFi because TVs are built poorly with cheap power supplies, poor shielding and improper grounding. Can anyone suggest a solution? How can I get the "ghost" image to disappear when I use the component video cables? Can I shield the TV somehow to stop the speaker buzzing? Should I ground the TV frame to my AC ground? Thanks for any advice in advance.

-DAVE
davesmith3
estrnad's avatar
estrnad
117 posts
 
I think you may need to uncouple the cable ground from your audio system ground. There could be a loop. Use a floating ground ballun on your coax cable, such as the "M.A.G.I.C. box ground loop eliminator. Audio Outlet, among others, sells it: 914-666-0550.
phild
603 posts
 
Check out jensentransformers.com...they have an Isomax piece that sells for about $50. Radio Shack may have a cheaper option...I'm not sure. I used the Isomax. It took the hum away, but it wreaks havoc with the local broadcast channels (received thru my cable). THe other channels...all digital cable..are fine.
treyhoss
287 posts
 
I'm not trying to sound like a smart-ass but I suggest you move the TV! Do you live in an apartment? I read an interesting article once about a problem just like you describe from someone who live in an apartment building. It turned out his TV was near a metal "beam" that ran behind the wall and acted like a superconductor. The article was much more technical of course but the solution ended up being movement AND orientation of the TV. Good luck.
davesmith3 OP
4 posts
 
You're right; I do live in an apartment. My local audio guru just suggested the same thing, to try moving the TV. He stated that simply re-orienting the TV could eliminate the problem just as re-arranging the rabbit ears on an old TV changed the reception. Your comment on the metal beam is interesting. I live in an older building that is steel beam construction (unlike many modern re-enforced concrete structures) and my TV is spaced between two windows where there most like is a vertical metal I-beam. I will try this soon. Unfortunately the TV will only fit in its current location, so then I need to find some way to shield the TV. Any thoughts? Thanks again.
-DAVE
treyhoss
287 posts
 
Dave, Wish I could help you there. I can relate to your dilemma anout TV placement. Perhaps you can investigate shielding the tuner portion of the set. This would have to be done internaly within the TV by a qualified person but would probably be the least "noticeable" way to deal with the problem. Before you go that far, you may want to test out some power conditioners or other RFI reducers. Good luck!
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