NeoGeo 50 60 Hz Mod

[Dampfwalze]

Hi

I have the possibility to buy an PAL NeoGeo but I want to have full speed etc. so I need to mod it to 60 Hz.
There seem to be 2 different board revisions: old one, with small extra pcb and the newer one without the extra pcb. To mod the newer revision should be no problem, according to a website I found, but I didn't find a manual for the older revision apart from the gamesx one: http://www.gamesx.com/importmod/neocart5060.htm
But this one ist not really helpful as it is very vague about what to do.

Does somebody please could help me? Maybe you know a better manual for the old revision, or did that modding yourself and know exactly what to do?

Thank you very much in advance.

 

[Xian Xi]

It would be pin 7 on the encoder to switch from PAL to NTSC. VCC=NTSC Ground=PAL. But if you want to keep it at 60hz but in PAL color, I would think you just need to swap the colorburst crystal to a 4.43361875mhz. Hopefully someone can clarify or confirm this.

 

[Dampfwalze]

Thank you for your fast answer.
But where on the pcb is the encoder to find? And do I need to change the colorburst crystal if I stay with RGB output (I don't care for composite video).

PS To count the right direction, is it clockwise or anticlockwise from the mark on the chip (looking down on it).

 

[Xian Xi]

If you are using RGB then I don't think you need to mess with the encoder at all. Maybe just the crystal. But MKL or channelmaniac would know for sure.

Don't do anything until someone confirms.

 

[Dampfwalze]

OK. Thank you.
By the way. The Board seems to be an 3-4 revision (numbers visible through the module shaft).

 

[Dampfwalze]

I think I found a solution for this board revision.
Thank you very much for your help.