Battery powered A1200

[motorollin]

Now I've got the A1200 that's never "bin" opened, I'm thinking of making it a portable games machine. I'm going to remove the floppy drive (I assume it'll still boot without it?), and put in an IDE flash card reader instead of a hard drive, and add a RAM expansion. I then want to power the whole thing from a battery so I can make it truly portable.

I'm aware the A1200 has a 5v, 12v and -12v supply. So my first thought is to get a 12v battery and split the 12v supply 3 ways. One would supply the 12v, one would supply 5v via a transformer, and the other well I don't know, how do you make +12v in to -12v?! I would have thought I would need to transform 220v to 12v and rectify to a negative voltage? Or can I "convert" +12v to -12v?

Also, how much current would a system like this draw? Is it realistic to power it from a battery?

Sorry for all the questions. I'm excited :-)

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moto

[motorollin]

Ok, I'll give the battery a miss :-) I'm going to remove the power supply from my XBox as it is fairly long and narrow, and not very tall, and see if I can cram it in to the A1200  :-D

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moto

[motorollin]

I've tried to find one of those 12v -> ATX converters, but I can't find one on the site you mentioned. Could you sort me out with a link?  ;-)

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moto

--EDIT
I think I've found them. Any of these look any good?

--EDIT
Actually, this is a better link.

[motorollin]

Would 60W be enough for an A1200 with a RAM expansion and an IDE compact flash device, with the floppy removed? Also, any thoughts as to battery life if I powered this off a 12v battery?

Thanks as always for your help guys :-)

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moto

[motorollin]

Wicked :-) I guess I can calculate the time I will get from the battery based on the current drawn by the ATX converter and the number of amp hours of the battery?!  :crazy:

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moto