This mod replaces RF modulator in original white model PC Engine with Mega Drive 2 style Mini-Din-9 RGB-video and audio out.
This is my own design based on two common schematics available online. The amp board has Voultar’s THS7374 based RGB amp circuit and Mobius’ audio amp circuit on the same board.
Stereo audio from HuC6280 chip comes directly without amplification to PCE expansion port and is very low volume by default. The amp board has a simple LMV358 opamp amplification circuit designed by Mobius that amplifies the audio to line level.
I also designed an adapter board for installing Mini-Din-9 connector to PC Engine and adapter for PC Engine expansion port for easy wiring of the amp.
The project is open source. See my Git for more information and install tips.
The kit includes the following parts
The Amp board
Mini-Din-9 socket and adapter board
Adapter board for expansion port