This circuit was obtained from the February 1992 Radio Electronics magazine. In it, a bar of 4 LEDs flashes continuously at a speed given by C1 and the setting of R3.
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...