This circuit is from a Radio Electronics from July 1965. The circuit uses components from the time also controlling a servo from the time. The power supply is 28 V.
This circuit was found in an American documentation from the 90s. It can be implemented with...
This 2-terminal regulator was obtained from a 1990s National Semiconductor manual. The components admit...
This circuit uses a photocell as sensor and a sensitive relay according the power supply voltage....