We found this circuit with duty cycle adjustment in the May 1988 Radio Electronics magazine. The source must be symmetrical, and the frequency given by R3 and C1.
This circuit was found in a 1962 publication. At the time there were high voltage batteries like the...
Suggested by Sprague in the 1980s documentation, this circuit can control three-phase AC motors....
This circuit divides the frequency of a 2 kHz signal by 2. The circuit was found in Philips...