I've been tinkering with an SMS II (integrated Alex Kidd) for a while:
I've read tons of howtos, guides, etc but I can't still make this work.
My aim is to have a SCART socket
on the back of the console for A/V output.
This tutorial http://kaikoshumi.webs.com/mastersystemiimod.htm
seemed to fit my needs, I also had the same chips on the board, but was intended for a captive SCART cable, not for a socket.
This guy http://www.electronicspoint.com/adding-rgb-scart-sega-master-system-t241450.html
wanted to perform the same mod I'm trying to do, but had a different motherboard revision (with different chips).
This is my setup so far:
I can see a nice video (composite, since the C-video signal goes to pin 19), but have no sound.
Notice that the RGB switching and Audio pins are not wired:
- If I wired the RGB switching signal to the correspondent SCART pin
(I've read different stories on this one: pin 16; pin 16 and 8; directly to pin 8, then 180 Ohm to pin 16)
moving the C-video signal to pin 20, I should get RGB picture instead of Composite: tried them all, all lead to massively distorted picture
- I can't get the audio signal from any known contact on the board!
(all these contacts have been tested with either a 10uF or without it)
- SEGA 315-5246 - pin 15
- Sony CXA 1145P - pin 9 (also tried pin 8 in a moment of extreme discouragement)
- Negative leg of cap marked as C31)
- probably more
This mod should have been extremely easy, but...
Now, I don't care if all I can get is Composite video; all I want is a decent audio!
My idea is: since there is audio output if I plug the ol' crappy RF, where can I get it?