Power Supply in this post is using a regulator which is composed of 2 pieces of NPN transistor. A transistor acts as a power regulator and a transistor again serves as a controller output voltage. Power Supply has an adjustable output with a range of 6-12 VDC. The part that serves as a power regulator is Q1 TIP31. Then the controller output voltage is a voltage divider composed of R3, R4, VR1 and R2 provide bias to the base of Q2 to control the power regulator Q1. In a series of power supply is mounted 5.1 V zener diode which serves to make the minimum limit the output voltage with Q2.
Power Supply With transistor circuit is quite simple and can be made with the PCB holes, so for those who want to try to directly mempraktikannya. May the power supply circuit can be useful for readers, especially for friends who need a power supply circuit with the regulator transistor.