If your load. 1. Use a constant current at all times. For example coils, LEDs, lamps, Resistors, Heating coil, DC motor, etc. 2. Has a fixed DC-regulated circuit inside. For example, mini TV, Monitors, and m. If you have a small load using the current lower of 30mA. You use a Zener diode voltage regulator is enough. Watch in the circuit below. We use 0.1A transformer only, And the po. For load use the current lower 1000mA. I think using the LM7824 voltage regulator is best. It is easy and cheaper than a Zener diode and transistor regulator. Look at above 24V 1A po. If you have only 7805. But you want to make a 24V 1A regulated power supply. We can do it with potentiometer VR1 and R1-resistors. It is easy but useful. When we adjust VR1 to hig. 24V 2A power supply circuit Diagram This is a type of series voltage regulator. Some called it Transistor Series Voltage RegulatorIf you want to learn more. Click.
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