TurboGrafx / PC-Engine
Here are the documents in regards to modding a TurboGrafx or PC Engine system with RGB and playing USA and Japanese system via switches. I also include some general pinouts and information on the systems too.
Please note, it can take a couple of minutes for the PDF’s to load! 
Note: The system is harder to get to grips with the variation of the consoles for this system than usual, in regards to the Europe/American/Japanese variations of the systems, add-ons and special HUcards needed for that. I have probably made errors in this part of my documentation, in which case apologies. Did my best to understand this stuff but not being a “fanboy” didn’t spend ages trying to check everything, so probably some errors. In saying that, all the documentation in regards to their modding and the project work I undertook are entirely accurate.
TurboGrafx guide – part 1
TurboGrafx guide – part 2
IntoGrafx build
Other information
An excellent forum site is this one: PCengineFX
A great site for magazine scans is this one and a good site for further reading
Some of the guide was from http://www.gamesx.com/rgbadd/rgbturbo.htm in regards to RGB modding, however as my TurboGrafx was PAL I had far greater success tapping off the CTX chip, which I managed to find documentation for on the net after a fair bit of searching. If I were modding a USA or Japanese TurboGrafx/PC-Engine in the future, I would wire the RGB directly to a CTX chip given the choice, as it amplifies the C-Sync line easier.
Do you have templates or something for the cases?
Changing case styles now for large format GBA style.
Could you build one of these for me? I noticed a message on the IntoPlay that said you could, but not for CD-game systems.
Can the PAL TurboGrafx be modded to output 60hz?
Doubt it, if you can it would mean changing the clock crystals.
Hey, you didnt even credit NFG for the instructions/pictures! please update your PDFs!
http://www.gamesx.com/rgbadd/rgbturbo.htm
Added as requested, however I must add that as my TurboGrafx was PAL I had far greater success tapping off the CTX chip, which I managed to find documentation for on the net. If I were modding a USA or Japanese TurboGrafx/PC-Engine in the future, I would wire the RGB directly to a CTX chip as it amplifies the C-Sync line easier. Each to their own! In other words, added your documentation as useful information, and thanks for that, but ultimately didn’t use it in my actual project as I had an alternative!
Hello, Bacteria! I read the guide – very nice! Although the UK/Euro version of the Turbografx is virtually identical to the US, and the US and Japanese systems are not similar at all.
Guts of the TG (PAL TurboGrafx) and TG-16 (NTSC TurboGrafx-16) are the same, apart from the crystals and their wiring, and the CTX chip (on the PAL not NTSC). The PCE look far different and far smaller and compact.