A DC power supply can be hard to find and expensive. With features that are more or less hit or miss for what you need.
In this Instructable, I will show you how to convert a computer power supply into a regular DC power supply with 12, 5 and 3.3 volt outputs. For about $10!
Why use a computer (ATX) power supply? Well, they're available everywhere, and they can output tremendous amounts of power in a small form factor. They have overload protection built right in, and even a 500W model can be reasonably priced with high efficiency. The voltage rails are incredibly stable. Giving nice, clean DC current even at high loads.
Plus, it's likely that many of you simply have an extra one lying around doing nothing. Might as well get the most value for your investment.
Step 1: Getting Started
The first order of business is that of safety. While I'm reasonably sure that there isn't enough residual energy to stop your heart, those capacitors can still bite, and that can cause significant pain and maybe even burns. So be paranoid when getting close to the internal circuitry. It would probably be a good idea to put on some insulating gloves. Also (obviously) make sure the thing is unplugged. You are responsible for your own safety!
Here are the tools/parts needed:
3 x "Banana Jack" Insulated Binding Post sets
1 x bag of "#6" Ring Tongue Terminals (16-14 gauge)
Small bit of heat shrink.
Ok, let's get to voiding some warranties!