This circuit was found in an American documentation from the 70s. The operational amplifier is from that time. Modern equivalents can be used.
This circuit can control the power from 0 to 70% of the maximum power on a load. The circuit was...
This circuit was found in an English publication from 1989, but it can be easily assembled, as the...
Found in the March 1992 Radio Electronics magazine, this circuit has two supply voltages. The...