Can a Jap Super Famicom be modded to 50Hz?
I have just modded a JAP and UK Snes, and the UK one works fine, swapping from 50Hz to 60Hz, but the Jap one does nothing - remains on 60Hz all the time.
I've tested out my wiring - all continuity from switch to ppu pins is fine.
Just trying to do a sanity check.
Ok Thanks.
Not quite clear where I've gone wrong then, as the pins are getting 5v or ground depending on the switch as expected.
Same pins I take it? It seems setting the pins (30 and 24) to 5v or 0V has no effect on the ouput. Weird. I've modded loads of PAL snes', but not seen this...
AFAIK, yes it's the same.
Well, I redid the mod completely. At the same time I modded to other PAL Sneses.
Both the PAL snes' now swap 50/60Hz perfectly, and still the jap snes will not shift from 60Hz. At all. Its rock solid. I used new switches, a different resistor (in fact one pulled from a another working mode). Bleeped out all the connections once soldered.
I can only guess more human error.
I notice this is an extremely old jap snes - it is a plug-in sound module in silver casing at the back that physically detaches from the motherboard, which I believe means its one of the earlier snes models.
Is the writing on the PPU different? Perhaps the PAL function was in a later revision.
Well they are still labelled PPU1 and PPU2. Also I have had confirmation that at least some models with SHVC plug in sound module can be modded no problem.
I've also read the voltages while running. 5V is getting to the correct connector on the switch via the 2.2k Ohm resistor, but when the switch is flicked, that connector is being pulled to ground, and the full 5v is dropping across the resistor, leaving all the contacts at 0V. (0V is 60HZ for NTSC machines).
So either the SPDT switch is faulty, or there is a pin short or similar. I attempted shorting the power regulator 5V output direct to the switch center contact (i.e. 5v from the regulator direct to pins 24/30 bypassing the switch) and it depowers the console. This points to a short again. (its a wonder I have not blown the fuse.
UPDATE: Turns out the switch was faulty after all. Amazing - was connected all 3 pins together when flicked, essentially grounding the +5V connection, so having a chunky over-rated resistor probably stopped it blowing the voltage regulator or fuse....
Now works a treat.