Distorted line at top of Plasma Picture

by JackTwist1 Jan 16, 2006 10:45AM PST

I recently purchased a Panasonic 42" Plasma TV TH42PX5OU. I have noticed that on some TV programs there is an intermittant white line that runs across the top of the screen. Some times it is a broken line. When there is a black picture at the top of the screen you can see the white line. It happens on certain commercials, sometimes for an entire broadcasted show. Sometimes on the HD channels, sometime on the SD channels. It seems very variable. What causes this and is it normal? Thanks.

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ANY INFO ON THAT LINE ???

by RORODAD Feb 10, 2006 4:55AM PST

I also am experiencing that white line only on certain cable channels (CNN,MSNBC)The line Never goes away while watching these channels. I have aPanny EDTV. Model # th42pd50u. If you have found an answer, PLEASE let me know, Thanks, Bob

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Possibly...more info needed, please.

by HighdefHoney Feb 13, 2006 11:38AM PST

What cable type you using to connect your box? What type of HD box is it? And thirdly, what resolution is your TV set at, 1080i or 720p?

-Honey

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That white line....

by RORODAD Feb 13, 2006 7:46PM PST

I subscribe to Cablevision which gave me a Scientific Atlanta HD4200 cable box. The wiring is a Monster DVI/HDMI cable. I have it set at 1080i. I've read on AV Forum that some people are experiencing the same problem.I appreciate your help.

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I am getting the white line too

by eddyhermann Feb 21, 2006 12:58AM PST

on a Panasonic 42" Plasma EDTV - seems to mostly be on the NBC, ABC, CBS HD channels, not on Discovery, HBO etc...

If I remember correctly, the NBC etc channels are broadcast in 1080i. I am wondering if changing the resolution down to 720 at least might solve our problems. I am going to run a test and report my results

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Distorted line at top of Plasma Picture

by jcrobso Feb 21, 2006 1:48AM PST

I'll try to explane this now that I have seen it on a couple of plasma TVs.
There is something called the Vitrical Blanking Inteval, see links below.
They can put info in this time space between the video frames. You never see this on a CRT TV because of over scaning.
Digital TVs may or may not overscan, if there is a lot of info in the VBI space it may show up on the screen the very top of the screen as black area with with bars in it. I don't know of any fix outside over overscanning, Don't know if you can change this on plasma TVs. John

http://whatis.techtarget.com/definition/0,,sid9_gci213677,00.html
http://www.webopedia.com/TERM/V/VBI.html

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Distorted line at top of Plasma Picture

by jcrobso Feb 21, 2006 1:59AM PST

Now that I have seen this on a couple of plasma TVs I have an idea what it is. Read the links on Vertical Blanking Interval below.
On a CRT TVs you never see this because of overscan.
Digital TVs may or may not overscan. When I saw this it looked like the plasma was showing some of the VBI on the top of the screen, If there is a lot of info in the VBI it will look like a black area with white areas. John

http://www.norpak.ca/article.htm
http://whatis.techtarget.com/definition/0,,sid9_gci213677,00.html

Distorted line at top of Plasma Picture

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