This circuit supplies 5 V from two AA batteries. The output current is 4 mA, resulting in an 11 mA input current from the batteries. The circuit is from an old EDN.
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...