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NEC TG-16/TE/TurboDuo => TG/PCE Repair/Mod Discussion => Topic started by: Wertwertx on November 21, 2016, 06:27:41 AM

Title: PCE Duo Scrambled Graphics
Post by: Wertwertx on November 21, 2016, 06:27:41 AM

My PC Engine Duo is outputting glitched scrambled graphics, similar to the way NES games appear when carts are dirty. It appears this way with all software, including the CD boot screen (see image link below) There has been no audio distortion or the general telltale signs of bad caps.

https://goo.gl/photos/godLqgLSGRKSojzy7

I am looking for help to diagnose this problem and where to get it repaired. Thank you.

Title: Re: PCE Duo Scrambled Graphics
Post by: Necromancer on November 21, 2016, 07:08:48 AM

Borked traces or corrupt ram?  I don't know what's wrong, but I'd send it to thesteve for repairs;  that dude can fix anything.

Title: Re: PCE Duo Scrambled Graphics
Post by: thesteve on November 21, 2016, 08:07:50 AM

It's either a bad huc6270 or bad traces to the ram by the 6270

Title: Re: PCE Duo Scrambled Graphics
Post by: thesteve on November 21, 2016, 08:08:11 AM

Or bad ram

Title: Re: PCE Duo Scrambled Graphics
Post by: Wertwertx on November 21, 2016, 09:18:39 AM

Thanks for the quick response. How do you think I should move forward? Do you do these repairs?

Title: Re: PCE Duo Scrambled Graphics
Post by: thesteve on November 22, 2016, 05:22:24 AM

I can do it
To move forward, run a finger across the ram chips while watching the picture
If it changes its an open Trace

Title: Re: PCE Duo Scrambled Graphics
Post by: Wertwertx on November 23, 2016, 02:53:52 PM

Despite my best efforts, I haven't been able to get my PCE Duo open to run my finger across the ram - it requires a screwdriver that I haven't been able to track down locally.

If I were to send it your way to fix it, how much do you charge for this kind of repair + parts? Do you do recaps (if I need them) or RGB mods (which I have a framemeister and am definitely curious about at least).

Thanks in advance.

Title: Re: PCE Duo Scrambled Graphics
Post by: thesteve on November 24, 2016, 05:47:01 PM

i do all those things
the screwdriver is a security or drilled torx

Title: Re: PCE Duo Scrambled Graphics
Post by: Wertwertx on November 25, 2016, 10:47:38 AM

I enlisted my local game shop to help me get my Duo open and diagnose the problem. We tried running our fingers on the RAM chips with the Duo plugged in and saw no changes to the picture, which makes me assume that its a problem with the RAM itself and not the traces. I took some photos of my console so that you can have a look. Note that my console has a region switch installed:

https://goo.gl/photos/6QfuYNCnxE7Uu9Kr5

https://goo.gl/photos/9p39BJMmb76czmHv7
https://goo.gl/photos/qmkZ2SqWco7D3oGu5
https://goo.gl/photos/EooJ1S12HR7kXBjJ8
https://goo.gl/photos/EjSL5LJFLSVdAogA9

If possible, could we take this conversation to PM to discuss specifics about your services? Thank you.

Title: Re: PCE Duo Scrambled Graphics
Post by: thesteve on November 25, 2016, 12:05:05 PM

note the system and video ram is underneath the board, so if it wasnt pulled from the bottom chassis when you checked, you didnt get there
PM,ing