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NEC TG-16/TE/TurboDuo => TG/PCE Repair/Mod Discussion => Topic started by: Jumpingmanjim on March 09, 2025, 06:14:25 AM

Title: PC engine GT scrambled/glitchy graphics
Post by: Jumpingmanjim on March 09, 2025, 06:14:25 AM

Hey everyone, I got a PC engine GT from Japan, opened it up, replaced all the capacitors and fixed a trace that had been rotted away by the capacitor juice.

Switched it on and now experiencing misaligned/glitchy graphics (This is Valkyrie no densetsu for reference)

(https://i.imgur.com/6scPiF5.jpeg)

(https://i.imgur.com/LT9PFnR.jpeg)

Here is a video if you prefer:

https://i.imgur.com/qBBSvb7.mp4

any suggestions greatly appreciated.

Title: Re: PC engine GT scrambled/glitchy graphics
Post by: DrunkenMonk on March 10, 2025, 12:49:13 AM

Looks like there's an address line still missing. Check around the 6280A, make sure each of the pins has continuity to the resistor arrays, sometimes the traces can be eaten UNDER the white silk screen so you can't see that they're damaged. There's also some vias that can get leaked in and the connection through the board destroyed

Title: Re: PC engine GT scrambled/glitchy graphics
Post by: Jumpingmanjim on March 18, 2025, 09:29:46 PM

Thanks for that, one of the traces from the graphics chip to the vram was bad.