This 0-30V power supply is the variable voltage Regulator at 2A max, by used IC-723for control volt stable regulated. The 2N3055 power transistor for boost up current to 2amp. It suitable for general electronics work shop. Because it is a simple circuit and easy circuit. In addition to this has the over current protection as well. This circuit is designed using LM723 voltage regulators IC DIP 20pin maintain a constant voltage, and a power transistor as the way through the current to can be used up as wanted. The circuit was designed also with overload protection or short circuit in the output. The amount of current flow will not exceed the set. Because it is monitored constantly by R4. When the current flows through the R4, until the 0.6V voltage drop across it. Making Q3 runs short the bias voltage between the base-emitter of Q2, it stopped working. Now, the Q1 stop working because does not has the bias voltage to base pin its, The output voltage is zero or down quite a close to zero. The potentiometer VR1 acts as adjust the voltage that enter to the LM723 for the volt output by you want. By the our circuit can adjust the voltage output from 0V to 30V. In use real, because the properties of the transistors used and values error of each device. Therefore, if the circuit can not be supply up to 2 A. Try changing the value of R4 is a lower value, until has the maximum current desired. Should be to use transformer 3A. The Transistor to Hold Heat sink as well. 0-30V 2A Laboratuvar tipi ayarlı güç kaynağı devresi yukarıda yer almaktadır..