Hobby Power Supply Kit using LM7805
This is a practical power supply for all your projects. It uses two 7805 regulators; input up to 20 VAC, or 30 VDC from a transformer or other power source. There are two outputs; one regulated at 5 VDC, and the other one is variable. This is an excellent introduction to power supplies.
Hobby Power Supply Kit using LM7805 Reviews: