Dual Power Supply

(for use with the JFET preamp)

Schematic (GIF 6k)

PCB (GIF 10k)

Components Layout (GIF 19k)



(click on schematic for larger version)


Some brands of electrolytics have a small inductance which will cause the regulator ICs to oscillate. Use tantalum caps for C5/C6 to be sure (but also most normal electrolytics will work).
The 7915 (at least the "made in Morocco" I used) needs a small load (some mA) to work correctly. If you get funny voltages (-18.4V or so), put a resistor from the 7915 output to ground (2k2 works good). Or it might be a good idea to put the "power on" LED with a 1k5 resistor to the negative rail (take care of polarity!).