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Hi,


I did a search on the board, but have not found an answer to my problem so I am hoping somebody can help me out. I am a novice, so I will keep it simple.


I just purchased my first high-def LCD TV and hooked it up tonight to my Comcast HD/DVR box. I had an old CRT Panasonic hooked up to the box with no problems via a coaxial cable. Coaxial from wall to cable box and then coaxial from cable box to CRT.


Now, I have the coaxial to cable box and then multiple color cables from cable box to LCD TV. Since I hooked it up to the LCD, I see faint horizontal bands traveling slowly from the bottom of the picture to the top. When I play a DVD the lines go away, so I assume it is something to do with the cable box or comcast cable line. The TV plays great with the DVD going, no lines and crisp picture. I did a little google search and figured out this is probably a 'ground loop' problem. First off, why did I never see this on my CRT TV, and still do not on my other existing CRT TVs in my house. Only on the LCD. Is it because the CRT TVs are two-pronged plugs, and the new LCD is a three-prong plug with a ground? Next, what is the easiest way to fix this?? Again, I am a beginner so treat me with kid gloves. Thanks for any help you can give with my problem.
 

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Is it because the CRT TVs are two-pronged plugs, and the new LCD is a three-prong plug with a ground?


Exactly. First thing to do is to verify that that the cable line is bonded to the house grounding electrode as called for by the National Electrical Code (NEC). If you live in a single family home, you can do this your self. Find the point where the cable comes to and enters the house, there should be a ground block attached to the sidewall with the cable entering and leaving it. Also attached to the block should be a ground wire going to the same grounding point as the electric meter and/or circuit breaker panel. Make sure that all connections are tight. If you are uncomfortable with doing this or live in a multible dwelling unit ie apartment, condo etc. then call the cable company to do this. When the tech comes follow him/her and question anything that doesn't look right.


If this doesn't work then get an outlet tester at the hardware store, this has three neon lights that verify that the outlets are wired correctly. Use it to check the outlet that the TV is on and any other outlets that are used by other cable devices, ie cable modems, second TVs, etc. Have any issues resolved.


If all this doesn't work then you probably should buy a "cable isolator" such as this Viewsonics VSIS-EU Isolator:

http://emersonnetworkpower.com/webap...og%20Rev03.pdf


There are other units out there, just use Google.


I hope this helps, Mallego
 

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In addition, under no circumstances should you ever even consider lifting the ground on the AC cord.


You can also check Calrad.com for isolators as well.
 
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