Found in a 90s EDN, this circuit is indicated for power control through a 4-20 mA line. The circuit makes use of optical couplers of the time.
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...