Found in a documentation from the 70s, this circuit can be implemented today with ease. The relay is of the alternating current type.
This useful power supply was found in an 1985 Italian publication, but can still be assembled...
This dimmer for 12 V incandescent lamps was found in a 1966 General Electric documentation. The circuit has...
With this circuit any number of 4017 integrated circuits can be connected in series. The circuit is...