Quick PSU sanity check

[Loccy]

Will one of these

 

http://www.maplin.co.uk/Module.aspx?Module...r&doy=22m12

 

run my UK woody OK? It's 500mA with a voltage between 3V and 15V, and it has a 3.5mm mono jack. But are there any other gotchas that I'm missing?

 

(yes, I know, I'm sure I can pick one up cheaper, but I can pop down to Maplins and pick one of these up rather than having to wait for one in the post).

[Shawn]

yes

[Uzumaki]

Should be fine. You could set it to lower voltage than the usual 9v to help the 2600 voltage regulator run a bit cooler. Something like 7.5 is the minimum for standard 7805.

[elliott]

That adapter outputs AC, it will fry a normal 2600, you need a power supply that outputs DC.

 

The 9V one of these will work:

http://www.maplin.co.uk/Search.aspx?criter...R&DOY=22m12

 

Or if you want a selectable voltage output:

http://www.maplin.co.uk/Module.aspx?Module...4&doy=22m12

 

Or this one, which is on sale for 3.99

http://www.maplin.co.uk/Module.aspx?Module...4&doy=22m12

Edited December 22, 2006 by elliott

[A.J. Franzman]

Well spotted, elliott!

[+batari]

That adapter outputs AC, it will fry a normal 2600, you need a power supply that outputs DC.

Actually, AC will not fry a normal 2600, at least not right away. I think there is some isolation between the power input and the sensitive components.

 

I didn't check an adapter carefully once, and I ran 9v AC into my 2600. It not only didn't fry it, but it actually worked! The screen showed massive interference and the sound had a constant 60 Hz hum, but it did work.

[A.J. Franzman]

That's the effect of the big electrolytic filter cap sacrificing itself to protect the 7805 regulator. Leave it on too long and one or more of the following will fail: electrolytic filter cap, 7805, AC adapter.

[Loccy]

Well that was a bizarre morning.

 

Bought the £3.99 Maplins PSU; also had to buy another set of connectors as the PSU didn't come supplied with a 3.5mm mono jack. Got it home, plugged it into my new Woody fresh from ebay - nothing. Spent an hour watching the TV trying to tune into what was a non-existant signal. I'd actually got to the stage where I was thinking that either the PSU was faulty or the Woody was - I had noticed that as I plugged the PSU into the back of the Woody, there was a spark.

 

Out of desperation, and I was about to give up, when I decided to flip the connector on the end of the PSU around. Now I am absolutely positive that in doing so, I was flipping the polarity to the WRONG setting, ie. center negative. Not expecting anything I set the TV tuning itself - and up pops 1981 Atari (the minimalist title screen of Yars Revenge).

 

It was like coming home after 20-odd years.

[A.J. Franzman]

The Atari needs a tip-positive supply, so either you had it wrong initially, or your AC adapter wiring or the reversible tip is marked/assembled wrong.