For you who like antiques or the circuit is old, use old equipment comes to experience build is usable can jubilantly And still have an experience that good with. As a result should try build 0-30VDC Variable Voltage Regulator lap supply circuit. It can fine Voltage supply 0V - 30V and still fine current get 0A - 1A as well. For about the equipment not a problem use transistor 2N3055 and IC ua741 and LM301 seek easy certainly unless. This circuit still systematically protect shot circuit as well.
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