This automatic brightness control that uses an LDR as a sensor, was found in American documentation from the 1980s. Resistors in series with LEDs depend on the desired current.
This circuit is a continuation of the previous one, serving as a protector against overloads in...
This circuit can handle 25 A unde a 32 V voltage using a hight power old transistor. This...
This circuit was found in 80's Popular Electronics. Transistors are commonly used. The...