Re: ATX -> Apple2e powersupply adaption.

["Michael J. Mahon" <mjmahon@aol.com>]

General_Failure wrote:
> Hello everyone.
>
> Today  started adapting a mini-ATX powersupply for use on my apple//e.
> The original plan was to mount the Mini-ATX supply inside the case,
> however I discovered it will not work due to the specific way the fan
> is mounted to the top of my supply. So I opted to make it an external
> supply.
>
> To do this I grabbed about 2m of some nice 6 core cable from one of the
> local electrical businesses. I don't remember what the cable is called,
> but I can tell you it's used for industrial control applications.
> I also grabbed some heatshrink tubing.
>
> The mini-atx powersupply had an odd feature which I ignored. It has a 6
> pin connector, with only one wire in it. The pin spacing, organisation
> and sizing is close to the apple2e socket.
> The angles of the edges were different, but because of its slightly
> smaller outer size it fit.
> Like I said though, I didn't use that.
>
> So anyway, I started cutting and soldering tonight. Then I realised I
> don't have a -5v rail. I read
> http://home.swbell.net/rubywand/Csa2POWER.html that it is possible to
> build a little regulator to derive the -5v from the -12v. Does anyone
> have a simple schematic on that?

<snip>

> So, big question, how do I make the -12 to -5v regulator?
> If I can't get this soon the job of 8-bit server falls to one of my
> C64s. Now people, which would you prefer?

As others have said, a 7905 will do the job fine.

The *actual* drain on -5v is almost neglibible.  I'd be surprised
to see more than 50ma.  It just isn't that useful.

-michael

Parallel computing for 8-bit Apple II's!
Home page:  http://members.aol.com/MJMahon/

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