This precision speed control was obtained in an Electronic Design from the 90's. The output final stage power transistors must be in accordance with the motor power.
This circuit matches a source of high or medium impedance audio signals with a low impedance...
Found in a 1993 Electronics Hobbyst Handbook, this circuit uses components that are still common...
This pulse width-tuned circuit was found in the March 1996 issue of Electronics Now magazine. The...