How Do You Build A Variable DC Power Supply?
DC power supplies are used to supply DC power to various pieces of equipment. These power supplies are also used to test new and existing equipment. Variable DC power supplies are designed to produce a range of DC power. Most variable DC power supplies produce a fixed amount of DC power. The difference is the addition of a high power wire wound potentiometer between the power supply and the power supply output terminals. Strip 1/2 inch of insulation from the cut end of the extension cord. Connect these two wires to the 120 volt side of the transformer. Connect the two 120 v AC terminals of the bridge rectifier to the two 12 volt terminals of the transformer. Connect the 12 volt negative terminal of the bridge rectifier to the fixed terminal of the variable potentiometer. The fixed terminal of the potentiometer will be the negative output for the power supply. A wire can be run from the fixed terminal to allow easier access to the terminal. Connect a wire to the 12 volt positive termina
