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 [...]
High quality, 3A adjustable voltage regulator. Using LM317 and 2N3055 so easy and cheap. Adjust voltage in steps 3V, 6V, 9V, 12V. And In fine, 1.25V to 20V.
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.
A good DC switching power supply circuit form old computer that not used. It has used powerful, durable and works great.