This DC motor control uses a power operational amplifier. We found it in December 1984 in the Radio Electronics magazine. The amplifier must be mounted on a heat sink and the maximum current is 1 A.
The operational amplifier taken as an example is uncommon today, but the configuration can be made...
The integrated circuit used in this regulator is not easy to obtain, since the publication is from...
This configuration was obtained in a 1977 FET Databook. The circuit can be practically any JFET...