This is 5v 12v dual power supply circuit using 2N3055 and Zener diode for 12V then to LM309 or IC-7805 dc regulator IC for 5V output which easy circuit [...]
This is LM317 voltage selector power supply projects can select output 1.5V,3V,4.5V,5V,6V,9V at 1.5A current. you can use as as battery, so saving.
Multi voltage power supply circuit. There is 2 Dual output, The 12V are +12V,-12V, Ground. And also the 5V are +5V, -5V, Ground. All 1A max.