This circuit was obtained in an Electronics Now from the 90s. The circuit uses operational amplifiers from the time and the indicator is of the Sonalert type with internal oscillator.
This fast converter using operational was found in a 70s American documentation. The circuit can be...
This circuit uses two sensors that are placed at the intersection of a miniature railroad, causing the LED...
This RF wattmeter was found in an American 1980s documentation. The components are common and the...