This countdown electromagnetic ring launcher was found in an Electronic Hobbyst Handbook from 1993. The components can be difficult to obtain. Details of the launch coil were not given.
This circuit with a MOSFET is from an old American documentation. The capacitor should be leak...
This circuit of an old medical publication makes use of an integrated circuit of the time,...
The transistors on this circuit can be the BC548. The circuit is from English documentation from...