This circuit is DC to DC converter model step down voltage. That can modify voltage input 12V DC from be DC 6V , 7.5V and 9V by have the size current about 1A – 2 Amp think. Be easy circuit use Zener diode maintain one’s position voltage. Be stable and have transistor 2N3055. Perform enlarge the trend tallly go up fully be usable next , see the detail in the circuit and read to add
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