I've never seen one of these before so I was a little surprised when I opened it up.
Can it be 50/60Hz moded?
I can see the security chip so I guess it's disabled in the same way; by running pin 4 to ground.
Full size image: http://www.davejuk.com/files/new_pal_snes_mobo.JPG (http://www.davejuk.com/files/new_pal_snes_mobo.JPG)
I've killed a couple of these boards trying to find a 50/60Hz pin. Lacking anymore information I just went looking at which pins were tied to GND or 5V and changed them one by one. Not the most scientific approach, but it's worked for me other times.
I gave up after killing a couple. I've got a stockpile of SNES consoles with the older moddable board in them, so I lost interest.
From memory this board only provides composite video. The S-video and RGB outputs were omitted to cut costs.
This appears to be an old model SNES, not a SNESjr (the controller ports are not attached to the PCB). I'm not aware of any of these that don't do RGB or S-video, I'd suggest then that this model prolly doesn't have that problem.
As for a 50/60 mod, send it to me along with an NTSC version of same and we'll sort it out once and for all, hey? =)
I'll eventually get around to checking through my pile of SNES consoles... I may have both NTSC and PAL consoles with this version of the board.
You can probably mod it the same way as the SNES Jr - switch pin 111 of the large chip, and change the oscillator crystal. I don't know what I've done with my PAL "1CHIP" board, so I can't check it myself.
EDIT: Here are the mod details:
(http://img.photobucket.com/albums/v204/retroyoda/1Chip-SNES.jpg)
last i heard the 1chip board wasnt switchable, or was with excessive work.. but the previous post seems to show its been pretty much perfected.. that'd be the way to do it, i dont think theres a simple high/low option for it.