Found in a 1968 Ferranti documentation, this circuit can be implemented with modern equivalent semiconductors. With the indicated components the load can be a lamp up to 1 A.
This circuit that uses a mechanical tuning fork was found in Radio Electronics magazine from June...
In the presence of the supply voltage of a 3 to 12 V circuit, this circuit causes the LED to...
This circuit supplies a voltage of 110 V from car battery with 110 V x 100 W output. Transformer...