This is a simple DC to AC Converter circuit,to converts 12VDC to 220VAC 50Hz/110V 60Hz as adjust frequency output using CD4047,MOSFET,power transistor and more
Small Zener diode voltage regulator circuit with PCB, using transistor and few parts. it is simple and cheap fixed dc source circuit. As one of best choice.
Transistor Variable power supply 1A, 0-30V project with PCB. Using transistor boost current to 1A. No IC. No Zener diode. But steady voltage.