This cassette player motor speed control was found in the January 1991 issue of Radio Electronics magazine. The circuit is for voltages from 9 to 12 V.
This circuit, found in documentation from the 1980s, uses an operational amplifier from that time....
This low frequency sinusoidal oscillator was obtained in documentation from the 1970s. Operational...
This circuit was found in a 1980s documentation. It is intended for remote vibration monitoring...