Trinitron TV letterboxing / adjustment / service menu etc

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Restart_Point
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Trinitron TV letterboxing / adjustment / service menu etc

Post by Restart_Point »

Recently came across a 1997 Trinitron, decided it could be good as my first CRT. It's all working fine with my Japanese Super Famicom but I haven't been able to get rid of the top and bottom borders.

It's a PAL territory model (i'm in the UK) so it was designed to use here, but it reads and displays NTSC RGB signals fine. I have the remote and have gone into the service menu where I have adjusted Vertical size / linearity to max values and that has made some small improvement but it still doesn't fill the screen vertically. There's a very definite black area at the top and bottom of about an inch tall (this is a 21 inch screen) where no beams are being projected at all. I haven't tested this with a composite or RF cable yet as I don't have them but maybe they would act differently from the RGB cable i'm using.

Is this going to be impossible to improve further? I can only guess that because it was made for the UK market it will never show NTSC at full screen and the only way to do so would be to buy a different model, or a TV designed primarily for NTSC regions. Or maybe this happens in NTSC regions too and is not an issue at all?

Has anyone got experience of this? Cheers
Last edited by Restart_Point on Sun Jul 08, 2018 1:26 pm, edited 3 times in total.
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Fudoh
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Re: Trinitron TV letterboxing / adjustment / service menu et

Post by Fudoh »

never seen this problem on a Trinitron TV. If your TV is from the late 90s, it has an anamorphic 16:9 mode though, which will get automatically enabled when you provide a 5V voltage to pin 8 of the TV.

You can still switch between 4:3 and 16:9 using the remote.

Sounds to me as if you were trying to adjust the 16:9 mode and not the 4:3 one.
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Restart_Point
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Re: Trinitron TV letterboxing / adjustment / service menu et

Post by Restart_Point »

Fudoh wrote:never seen this problem on a Trinitron TV. If your TV is from the late 90s, it has an anamorphic 16:9 mode though, which will get automatically enabled when you provide a 5V voltage to pin 8 of the TV.

You can still switch between 4:3 and 16:9 using the remote.

Sounds to me as if you were trying to adjust the 16:9 mode and not the 4:3 one.
Haha brilliant!! There was a 16:9 option in the VCR section (this has a built-in VCR) so I hadn't looked in there yet as I wasn't concerned with using the VCR, and I have changed that to 4:3 and it's worked!!! Looks great. Seems to default to 16:9 every time the signal resets but its not a huge issue to switch back to 4:3. I wonder if that's because the RGB Famicom cable i'm using is providing the 5V at pin 8 as you say. After 25 years and crappy PAL consoles as a kid I can finally play Third Lightening and Mariokart at 60hz full screen (with no lag) :D Thanks
MarkOZLAD
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Re: Trinitron TV letterboxing / adjustment / service menu et

Post by MarkOZLAD »

It should be possible to mod the TV and run a switch to force 4:3 mode. Usually just by sending a 5V signal past the voltage divider on the Scart pin 8 circuit inside the TV.

Would need to see the exact schematics on the TV to comment further.
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pedroTFP
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Re: Trinitron TV letterboxing / adjustment / service menu et

Post by pedroTFP »

Hi guys,
I recently got a Sony KV-25T1A (service manual is here: https://freeservicemanuals.info/en/serv ... B/KV25M1D/, service from pg. 16 and on) for my retrogaming.

Everything is ok, except image looks a little rotated on the left size, as you can see here: https://imgur.com/a/DVb7CjO (low left angle, but the upper side looks ok...)

Is there any way to fix it without opening the TV? I tried all the service setting with no result. Maybe is CORR PIN or PIN AMP the one to fix?

Besides, what are RGB BLK, S-COR and V-LIN?

Thanks a lot!

(Sorry to hijack OP, but the issue didn't seem worth a new thread).
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