Re: [Kinda OT] Power Supply

[carbide@egine.com (Paul G.)]

julian814@hotmail.com (Ralph Glatt) wrote in message news:<ce9c44dd.0408170659.516c726b@posting.google.com>...
> I have a question about a power supply for a ZX81, but no one on
> comp.sys.sinclair seems to be willing to help me, but since it's a
> general question and not system specific, I thought I might get an
> answer here.
> 
> The ZX81 takes a power supply that puts out 9v DC around 800 mA. I
> needed one, and a friend gave me a 9v AC power supply and said use
> that. Thing is, I'm afraid if I use the wrong kind of voltage, I might
> fry the board, which I don't want to do, because the ZX81 isn't all
> that easy to get in the US. Should I try it, or should I keep looking
> for a DC power supply?
> 

9V DC adapters are very common, a lot of answering machines use 'em.
Of course, they don't use the same type of connector so you'll have to
wire one on.

I just looked at a Timex Sinclaire 1000, which I think is the same as
a ZX81. The AC adapter says 9.75V DC, 650ma. I checked with a DMM- the
tip is positive.

I seem to recall opening up a ZX81- I believe it has an internal
regulator, probably to regulate the 9V to 5V.

Hope that helps.
-Paul