12V to 9,7.5,6 VDC converter with 2N3055

12Vdc to 9,7.5,6 Vdc circuit

This simple converter using a Zener diode and a transistor into a 9V DC 12V DC battery power to the maximum 1A. The circuit is very simple to build, and requires only 3 electronic components, resistors, zener diodes and transistors. The 2N3055 transistors, 1N4738A Zener diode or Zener voltage and the same power. 3W, and possibly wire wound resistor 3R type. Powering a useful tool to use 9V DC.

The output voltage of the following formula:
Zener voltage Vout = + 0.65V, 0.65V, which is the base-emitter voltage of transistor