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  #1  
Old 03-24-2021, 07:58 AM
kf4rca kf4rca is offline
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Overscan Issue

This problem arose as a result of combining two sets into 1. They were both 40 inchers. The Westinghouse had a bad screen and the Element had a bad main board. These were both roadside finds and appeared almost identical inside. So I put the good main board into the one with the good screen. Everything just dropped right in. Or so I thought.
The result is a slight overscan at the bottom of the display where the crawl usually runs. Its really not a problem unless you like to read the crawls.
Question is: Is there any software to adjust this? Thanks.
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File Type: jpg Overscan.jpg (62.5 KB, 18 views)
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  #2  
Old 03-24-2021, 01:14 PM
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Jeffhs Jeffhs is offline
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Quote:
Originally Posted by kf4rca View Post
This problem arose as a result of combining two sets into 1. They were both 40 inchers. The Westinghouse had a bad screen and the Element had a bad main board. These were both roadside finds and appeared almost identical inside. So I put the good main board into the one with the good screen. Everything just dropped right in. Or so I thought.
The result is a slight overscan at the bottom of the display where the crawl usually runs. Its really not a problem unless you like to read the crawls.
Question is: Is there any software to adjust this? Thanks.
What is the problem? I don't see any overscan on the thumbnail you posted. The closed-caption display is right where it should be, and is readable. If you had noticeable overscan, the image would be so large the CC display would likely disappear below the base of the TV's display panel. If there is an adjustment for the size of the picture, I would adjust that until the picture fills the display. If there are no adjustments of this kind on the set, the picture size is likely regulated by software and, therefore, may not be easily adjustable unless a special pattern generator is used.

The above is about all I can offer as far as advice on your set's problem is concerned, since I have no experience with repairing or adjusting flat-screen TVs. If adjustments don't bring your TV picture back to full size with no overscan, it sounds to me as if there may be another problem somewhere. The only thing I can think of as I write this is maybe, just perhaps either the new main board or the display panel itself is defective, or maybe one or the other isn't 100 percent compatible with your TV. I am thinking flat-screen televisions are quite picky when it comes to replacement parts; the replacement(s) must be identical to the component presently in the TV, not unlike parts substitutions in older CRT sets. Parts substittions are to be undertaken if and only if the correct replacement part is not available; they may work in older sets, but I wouldn't trust them in today's flat screen televisions. The use of an incorrect component in a flat-screen TV could cause more trouble than you bargained for, including damaging or destroying the entire TV.

Edit: I just looked at the thumbnail you posted a moment or so ago and saw what you're referring to. Part of the picture is in fact missing, being pushed off the screen by the overscan problem. As I said, however, the picture size may well be regulated by software within the TV and may not be easily adjustable unless, as I said, there is an actual vertical height and/or linearity control, as there were in older CRT TVs. If there are no such service adjustments, the problem is likely on the main board or even the panel itself.
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Last edited by Jeffhs; 03-24-2021 at 01:29 PM.
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  #3  
Old 03-24-2021, 04:52 PM
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old_tv_nut old_tv_nut is offline
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Quote:
Originally Posted by kf4rca View Post
This problem arose as a result of combining two sets into 1. They were both 40 inchers. The Westinghouse had a bad screen and the Element had a bad main board. These were both roadside finds and appeared almost identical inside. So I put the good main board into the one with the good screen. Everything just dropped right in. Or so I thought.
The result is a slight overscan at the bottom of the display where the crawl usually runs. Its really not a problem unless you like to read the crawls.
Question is: Is there any software to adjust this? Thanks.
What menus can you access? Do you have the correct remote? There may be an overscan setting somewhere.

Is the source a cable box or satellite box, or over the air antenna? A cable or satellite box's menu may have an overscan setting.
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  #4  
Old 03-24-2021, 05:32 PM
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JohnCT JohnCT is offline
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If the main boards share the same platform, you can swap the eeprom from the bad board to the good board, assuming your eeprom wasn't the issue with the bad board.

I've seen all kinds of issues with that kind of swap. Sometimes a split screen, or upside down picture, or weird resolution issues etc, because the eeprom contains the software for a different screen.

John
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