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I need some help, my television seems to be cutting off the bottom of station logos. Here is an example of the Jimmy Kimmel show with the ABC logo at the bottom.




Also, here are some test patterns that I took pictures of, im sorry for the bad quality of these photos.







I was wondering if I could fix this problem. Any help would be great
 

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Originally Posted by sleepykidX /forum/post/18215216


I need some help, my television seems to be cutting off the bottom of station logos. Here is an example of the Jimmy Kimmel show with the ABC logo at the bottom.

The "cutting off" is due to overscan.

Overscan is displaying/projecting the image larger than the viewing area, which results in lost image around the edges. This is common practice for CRT TVs to conceal the fact that the low-cost power supply will cause the image to shrink during bright scenes and expand during dark scenes. Computer CRT monitors typically have much better power supplies, and will underscan: you'll see a black "frame" around the image.

Quote:
Also, here are some test patterns that I took pictures of, im sorry for the bad quality of these photos.


I was wondering if I could fix this problem. Any help would be great

Rather than just a grid, you need to display patterns that indicate where the image edges are. There are some patterns that show the "safe area" that must be displayed and the image boundaries. I like to use a large grid with circles in the corners; the "roundness" of the circles show if the horizontal is in proportion to the vertical. And you can tell if the image is centered on the screen (i.e. equal amounts of cutoff on each side and top and bottom).


You have to make the correction for overscan or centering in the Service Menu. The standard warnings about making changes in the Service Menu apply. Don't try to get rid of the overscan completely. It's still a consumer-grade TV, although one of the best ever.


The typical adjustment for correcting overscan (the image size) are the vertical and horizontal Amplitude (or Size). But adjusting Amplitude often affects Linearity or other adjustments. Also each electron gun may not respond identically to the adjustments and thus introduce convergence errors.


The focus, alignment and convergence of your TV looks good from the photos. Assuming nobody has touched it, it's not perfect geometry or convergence, but that is pretty good for a factory setup and after 5 or so years of aging.


Regards
 
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