Found in Popular Electronics from the 90s, this circuit turns off an appliance at the end of the programmed time. The 12 V relay must have contacts according to the controlled current.
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...