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 control for 12 V drills was found in a 90s Elektor. The components are current, and Q1 can be...
Found in an old English publication, this circuit applies to the 240 V network, but can be changed to...
This circuit was found in a 90s Popular Electronics. With it, using a 4066, it is possible to...