For experiments with a disk rotating at various speeds, the April 1998 Electronics Now magazine suggests this PWM motor control. The current with the LM317 is 1.5A maximum.
This circuit is from an old Elektor using components that are not currently common. The circuit is...
Pressing S1 the LED glows by a time interval depending on the capacitor. Time intervals in the...
Here we have an interesting circuit found in a 1981 publication that causes two LEDs to flash...