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bigtenball
02-17-11, 05:09 PM
I have a 3800 receiver, which I think has had a new smartcard put in it at one time if I can remember right. Anyhow, I do not have a flatscreen TV, I still have the old "curved" type screen. I'm sure there is a more appropriate name for it than that but I don't know what it is. Anyway, the problem I have is that a lot of what is being broadcast on the screen is being truncated so I can't see it. At first I only noticed it when watching sporting events. Often times the score is displayed on the bottom of the screen, however a big portion of it is down below the border of the screen so it is practically unreadable. But now I am starting to notice it with just basic graphics displayed on the screen, and they are being truncated not only on the bottom of the screen but sometimes on the sides as well. This is obviously quite irritating, and I'm just wondering if there is anything I can do about this. Is it perhaps somehow adjustable?

P Smith
02-17-11, 05:36 PM
It's CRT, and yes - you must adjust overscan on your TV [V and H-size], not the 3800.

bigtenball
02-17-11, 08:08 PM
I was afraid of that. It's an old Zenith TV from about the mid 1990s. I don't know if it has an overscan adjustment on it or not, and if it does, I sure don't know how to do it. *sigh* Well, back to doing more research. Thank you P Smith.

P Smith
02-17-11, 09:18 PM
It would be easy if you know analog circuits/components a little bit - remove back cover, you'll see a lot of pots (potentiometers) and each one usually has silk print close to it; find H-size and V-size while the TV disconnected from power outlet. After that, it would be hard part - powering the TV and trimming those pots ... using ONE hand and steady holding it, turn that pot, looking in a mirror showing an edge of TV screen, checking an effect ...

bigtenball
02-17-11, 10:42 PM
sounds like a good job for someone who knows a lot more about what they are doing then I do.

BattleZone
02-18-11, 07:49 AM
All CRTs (cathode ray tubes) use overscan, because the edges of a CRT will be distorted. But many CRTs are set with far too much overscan.

Flat panel TVs technically need no overscan at all, but most have a slight bit of overscan to hide the "closed captioning" lines that are otherwise visible at the top of an analog transmission. HD signals don't have this issue and really need no overscan at all.

The problem is that you will increasingly be watching TV shows formatted for HD, and therefore for flat-panel TVs with very little overscan, as networks do away with their separate SD feeds and just convert the HD feed for SD customers.

So, in the meantime, you can have your CRT calibrated, and that will help, but sooner or later, you need to think about transitioning to a flat panel TV. Within 3-5 years, most SD feeds will go away, and nearly all TV will be formatted for widescreen flatpanel TVs, making TV harder to watch on a 4:3 CRT.

Michael P
06-06-11, 05:16 PM
I was afraid of that. It's an old Zenith TV from about the mid 1990s. I don't know if it has an overscan adjustment on it or not, and if it does, I sure don't know how to do it. *sigh* Well, back to doing more research. Thank you P Smith.

My Mother-in-law's TV was a 25" Zenith console from the late 1990's or perhaps the early 2000's. In any event the over-scan was terrible. You could not see the baseball scores back in the day when the box was at the top of the screen. We inherited this TV and put a CECB (digital converter) on it. Watching a 16 X 9 picture letter-boxed (as opposed to cropped) solved this problem.

Unfortunately an old E* SD STB will not allow you to watch any 16X9 except for the few SD channels that are not cropped. I have a ViP 622 and always watch 16 x 9 letter-boxed, even on my 27" sets (which did not share the same over-scan problem that Mom's Zenith had).