AC to AC adapters?

[kevman3d]

Bit of a noob question - as I want to create a replacement C64 PSU, I need a power adapter capable of outputting 9V AC - 99% of power adapters I have found output in DC, and they're easy to get...

So anybody know about getting something with an AC output? Would it require some kind of additional inverter or other device? Any suggestions welcome obviously...

[LilJoe]

http://www.instructables.com/id/9VAC-power-supply-for-x0xb0x/

[Clym5]

I found a couple of 9VAC adaptors in a box of assorted modems. If you can't find one, I think I may have one or two spare.

[kevman3d]

When you mentioned modem, I suddenly realised I had a brand new 56k D-link still in a box on the shelf (behind everything I've stored up there).

Its 9V 800mA. Should I assume that the fact there is no +/- diagram on the bottom of the label (the one showing the polarity for the plug) and that it says its a Class 2 transformer that this is AC?

All I can say now is 'thank god for being a hoarder'

[kevman3d]

http://www.instructables.com/id/9VAC-power-supply-for-x0xb0x/

That's actually a really interesting tutorial. Thanks for the link...

[Clym5]

Sadly, 800mA won't cut it. You need 9VAC at 1.2 or 1A from memory. I never like to load up power supplies at anywhere over 75% of their rated capacity for constant current draw. 800mA powering a 1.2A device would either just shut the power supply down, or kill it quickly.

And for testing if it is AC or DC, it might show a symbol.

~ means AC and one with a flat line on the bottom and 3 dashes on top means DC. You could also find out with a multimeter if it can test both AC and DC.

[kevman3d]

I agree - having less then 1 Amp is looking a little too low for anything more then a cheap plastic modem

I'll keep looking in case there's something laying about elsewhere - I do have an old scanner and various old peripherals downstairs that occasionally have adapters - what they are, I'll check - Gives me something to look at on the weekend...

[xjas]

http://www.instructables.com/id/9VAC-power-supply-for-x0xb0x/

I use original Nintendo (NES) power supplies on my x0xb0x. 9VAC, 1.3A and pretty sure they're regulated (show ~9V on a multimeter with no load - but haven't opened one up to check). Granted they're nearly as old as C64 power supplies and getting hard to find.

Note: a lot of aftermarket NES PSUs are DC! (Anything that says "compatible with Sega/Nintendo" will be.)

[xjas]

Also I have a modern(ish) Linksys PSU here that is 9VAC 1000MA. No idea what model it came from though (and it's 110V only.) Might be worth scouring old routers/switches at a thrift shop.

[kevman3d]

Note: a lot of aftermarket NES PSUs are DC! (Anything that says "compatible with Sega/Nintendo" will be.)

lol! I noticed - I ordered a retrobit brand one for SNES/Genesis (dual output plugs of different sizes) and its 9V DC - though I read on a forum that the SNES can work with either AC or DC input (its not picky apparently).

My father-in-law is a hoarder of electronics and industrial equipment (50+ years worth). I'll shoot him a quick email as I know he's very likely got something (and my wife just said that her sister is going to visit him - handy for bringing stuff back to Auckland). Fingers crossed - we'll see what happens.

[SpidersWeb]

Don't take my word for it, but my understanding was inside the C64 the 9V AC goes straight in to a diode bridge except for one line to the cassette deck.
So if you're not running cassettes, you can run them on 10-12V DC which is much easier to organise. (Don't do this without checking first, it was just my "off the top of my head" memory)

[entomos]

When I put together mine I picked up both the 5V DC and 9V AC from Jay Car.

9V AC 1A - Without load it measured ~ 10 V AC from memory.
http://www.jaycar.co.nz/productResults. ... MIT=Search

This is the 5V DC 3A power supply I used.
http://www.jaycar.co.nz/productResults. ... MIT=Search

All up it cost me around $60 (both adapters, 7 Pin Din plug) brought a few spare din plugs as they can be a pain to solder.

[Clym5]

brought a few spare din plugs as they can be a pain to solder.

They sure can be! I actually lopped off the C64 end of a original PSU, as soldering DIN plugs are a pain, and it was free. Just went wire to wire.

[SpidersWeb]

Yeah I went through a couple of DIN connectors my first time too.

Some tips I found useful:

- cut a potato in half, place on bench, stab the DIN plug in - this will keep the other side of the plug cold, while also holding it steady for you.
- pre-tin / solder each wire - with only a small amount of wire exposed
- pre-fill each of the DIN pins with a tiny ball of solder at the ends

I guess the last two are common sense, but I don't always do it automatically because for most jobs I get away with not pre-tinning.

[RonTurner]

I wouldnt use Jaycars cheap DINs , inferior.