Super Famicom power supply replacement

Hi all,

I have an SFC that has terrible video glitches. The analog kind, not the dirty cartridge kind. I used a cheap wall wart replacement PSU. Suspecting it might be a power issue, I got myself a barrel connector and hooked up my adjustable bench PSU. Much better picture, not perfect, but confirming that the image issues are PSU related.

The original SFC power supply is a chunky linear / transformer one. Those are very low-noise so the SFC likely has little to no filtering and expects clean power. The crap wall-wart and my bench PSU are switching ones and I hope that I can get a perfect picture once I actually hook up a linear PSU.

But where to get one? I find here it's basically impossible to get a linear power supply, they are all switching ones, who knows which ones are noisy and not. I could import an original Japanese one, but that would require a stepdown converter and be time consuming and expensive.

The European SNES PSUs unfortunately output AC. I only noticed this once I got one. I have rectifier and a buffer cap and can convert it to a DC PSU, but I measure close to 14V DC after adding the capacitor. PSU design is not my strength and I don't know if I should go down this route.

I've seen Mega Drive Gen 1 PSUs that seem chunky (so given the size & age hopefully linear) and they even output 10V/1.2A. Maybe I should get one of these?

What would you recommend? Can I Frankenstein any of the stuff I got into a decent SFC PSU? Where can I source a 220V replacement PSU that won't give me any video artifacts?

Thanks! ;-)

 

I can find linear power supplies no problem.

Here is one on UK ebay - http://www.ebay.co.uk/itm/OEM-AD-10...252015&hash=item283e73f02a:g:sDMAAOSwIQdZLwy-

Regarding 14v thing, linear power supplies only have the rated voltage with load attached. If you measure without it being connected to something, it will be far higher.

 

I always use a Megadrive (Genesis) 1 power supply on my SFC without any graphical issues.

 

Ok, seems like the situation in the UK is different! I figured it was just an EU thing and they have been outlawed for being to inefficient like incandescent light bulbs. On German Amazon/eBay or in local electronics stores there's basically nothing. I only found a single model of a linear bench PSU and a few Mega Drive ones. Not a single new wall wart type device.

How would I correctly measure my rectified SNES PSU? Given that the SFC has a voltage regulator in it 14V should be fine, at least short term, but I'd rather only attach it to my console once I verified it. Can I just measure it with a 100Ohm resistor attached? Would that be meaningful?

 

your power supply will be fine, its 14v by design.

If it says its 10v, its 10v. The fact its higher with no load is just how unregulated linear power supplies work.

https://www.sparkfun.com/tutorials/103

 

Today was the flea market, no luck, the only linear PSU I saw was the SNES one I already had :/

But I read your article and did some more reading up on power supplies. I think I understand a little better now. I tried my rectified & smoothed SNES power supply on my SFC and it works just fine. Voltage drops quite a bit with the intended load attached. Video quality is also good. There's minimal amount of noise in solid green colors and I can see a tiny bit of the ghosting that 1-CHIP SNES consoles are prone to, but I'm very happy with the image quality now.

Thanks for your help!