On Wed, 25 Sep 2002, David Nicol wrote:

> There's this very old and neearly dead daydream of having
> a public internet-login at the Infinite Sun space, 1732 Oak,
> downtown.  That might be a good place to set up the cluster.
> Especially if they succeed in putting a windmill on the roof
> for the electricity.  Anyone feel like putting together
> a general power supply that can switch 24VDC into everything
> you need to make AT* motherboards happy?

How many watts do you need?  24VDC into 120VAC?  Many of the larger UPS
units use 2 12 volt batteries.  I've seen a lot of them discarded, just 
because the specially sized batteries died.  

I have a $60 600watt inverter from walmart that can easily be converted to
24volts.  The conversion would only require a small regulator for the 
control electronics and a few windings taken off the primary.

A DC to DC converter would likely be more expensive, because DC-AC units
are incredibly popular.  I suppose I could make one.  DC converters are so
much fun to design and like rocket science.  One mistake creates wonderful
fireworks and its back to the drawing board.  It usually takes a few dozen
tries to get a design perfected.  Not something I'd like to test with
nostolgic motherboards.  Except on the Forth of July.