12V Power Supply

[james McAllaster]

i scrap out old, dead computers so there's always
a pile of  the old "at" power supplies around
here. one is almost always running. fans,
speakers, testing anything that draws a low enough
amperage.

if anyone knows how to step to different voltages
i'd appreciate the feedback. i'd like to replace
the half dozen transformers i've got running at 6,
7.5, and 9 volts with a single "at" power supply.