The commodore power supply puts puts out +5 VDC and 9Vac (i'm sure it's actually between 10-12 Vac though, for some reason.. i'm jjst copying the first pinout i saw on google)

Anyhow.. i know the SID in the rev 2 motherbaord of C64 uses a 9 v DC to power the SID 8580 on it (becayse that runs on 9v DC)

my question is.. could you take the 9vDC and use that to power a psone screen? is the regulated voltage in the PSone screen only for part of the board, and 7.5 is used unregulated, through the PSU provided in the box, to the other parts of the board?

is 9v DC high enough to power a 7.5 regulator should i want to reduce it to 7.5, AND lastly, will it draw too much current and affect the SID chip itself? is there a way to protect the chip against any problems the screen might cause? diodes? caps? fuses?!

because of the recently rleased prophet 64 cartridge, i want to encorporate a psone screen, some pots, audi out and in jacks, etc.. so that my c64 is more easily playable live...

you understand..

so.. anyone who can help me?

edited: never mind, I'm stupid and thought you were talking about something else. (DTV setup)

to throw some reasonable input in, since there's no delete button,
I wouldn't try drawing enough current to run that screen through all those delicate parts on the c64 board. all it takes is for one of those not to like that kind of juice, and you'll be searching forever for a part to replace. An unmodified PSOne screen takes an awful lot of juice.

You could look for the bit that puts out the 9v to start with and look up the spec on it. It seems a better way to be sure than just trying it.

About powering the screen, Gannon suggests not putting more then 9v (or 9.6v) into the PSone as it has limited to the voltages the 7805 regulator can handle and other internal components. So you should no problems with running the PSone and Commodore 64 off one battery. Give picture when you're done.

Ahh, but the 9 volts is AC.

The screen takes 7.5 DC.

And from looking inside one, doesn't look like ALL the power is regulated... the regulatr seems to apply to only part of the circuit....

if i put a bridge rectifier directly at the input (the 9vac, which always actually measures about 10), then put in parallel a couple meg resistor and a 10uf capacitor, then take that and put that into an 8v voltage regulator... could taht work?

I don't know enough about electronics... i don't know how to calculate how much of a load resistor and how much of a capacitor i need to safeguard the bridge recitifier's output, to keep from ripples and surges and the like..

dammit.. i also don't know the minimum input voltage for an 8v regulator to work.. 9vdc might not be enough..

See, but you still need to worried about amperage. Because the screen takes about two amps to work comfortably. Or at least 1.5. And when you take away amps from the commodore, it acts funny.

I was thinking about it too, and if you just get a 7.5 volt adapter with a higher amperage output, you could get a regulator to drop it down to five, and supply the screen before the regulator, then the commodore. You just have to make sure the amperage is high enough to handle both draws comfortably.