This commercial circuit is from a Japanese magazine from 1967. It uses germanium transistors, and the coil can be made with 80 to 100 turns of fine enameled wire on a ferrite rod.
This circuit was obtained in a 1967’s EEE. Transistors and integrated circuits can be replaced by...
This circuit was obtained from HAM Radio magazine in an 80's issue. The FETs are types of the time...
In the event of a short in the output, the relay disarms interrupting the supply. To reset this...