Metropoulos Forum

My way of fixing the problem with 18v adapter. 9v to 12v internal voltage boost!

BOSS 9v 100mA adapter is enough to power 2 of these circuits => 2 different pedals with the voltage converters from 9 to 18 volts. And there is plenty of empty space for 2 9v batteries! Or one battery and a switch for true bypass mode.
Ic's are max1044/ICL7660. Cheap and very effective!
With 9v 500mA adapter you can power more than 3 with no noise issues
I had 40mA voltage regulators (78L12 and 78L15) - burned them all with this circuit, that's why I used 7812 and 7815 (1.5A rated). Schottky diodes - 1n5817.