The following circuit is very simple to make. The Max 38 and the 7905 negative regulator ICs can be purchased from Digi-Key at www.digikey.com . The other parts can be purchased at Radio Shack, Digi-Key or just about any electronic parts store.


The circuit can be assembled on a pre-printed circuit board like Radio Shack 276-150. Keep all leads as short as possible. Use an enclosure like Radio Shack 270-253 and ground the aluminum front panel.