50/60 hz mod help

[jantonio]

On the other day I soldered the extra capacitor to stop the screen wave of death XD (problem solved) and I took advantage of the half disassembly to solder two wires to the sw4 ( so I could play the majority of the games in full speed). The problem is that when I join the wires the image goes black (displaying the green AV1 icon in a weird way) only playing sound. If I disconnect the wire ( without turning the Saturn off), the console freezes (showing a corrupted image) and even the reset button stops working.

I know that my TV can display 60 Hz because it's a Trinitron kv-29fc20e.


If you can, I would like to ask you if you can identify my motherboard version because I think that my Saturn is mixed parts version (with no specific motherboard but with oval button) and to advise me about least destructive way to do the 60 Hz mod in my motherboard.

[zyrobs]

It's a VA1 PAL board. Those have a design error, the SW4 connector is still connected to the PLL, so using that will force the console to run at the wrong clocks (34MHz or so), hence the crash.

The most simple fix for that is tracing back the connection between VDP2 pin 79 and PLL pin 1, cutting it, and grounding it on the PLL side. There's a trace on the bottom of the board where you can do this, and with thin single strand (kynar) wire you can apply the grounding right there, without needing to lift any pins. I've done it recently, I'll see if I made any pics of it or not.

edit: found it:


You can see the trace I sloppily cut, and on the left side of the trace, the little white wire that connects to the ground side of the cap. The wire is 28AWG Kynar, it goes through the hole in the PCB making the connection very secure, it doesn't just grab the bottom of the board but it is soldered to the entire via.