Battery Charger Circuit Description Q1 & Q2 make up a power Darlington using the venerable 2N3055 power transistor. The base of the Darlington is controlled by Q4, the voltage regulator transistor—it ...

6V Battery Charger Schematic. System diagram. Voltage pre-regulator. ... Started building my first hobby circuits at age 11 using the venerable 1N34A diode & 2N107 transistor. In high school, ... 24V, ...