This regulator can use BD'136 as the main transistor and as a reference next to a BC548 zener. The circuit provides a voltage of 9V from 12 to power devices that use batteries.
We found this active crossover in a Radio Electronics magazine from June 1961. Note the different...
Found in Popular Electronics from the 90s, this circuit serves to indicate the output level of a...
If you are on an old PC that you use for experiments, control or other applications, this circuit is...