Power source for tubes (T384E)

This experimental bench source was found in a modern book on tubes. The components used can be easily obtained.

Battery controlled switch (CB8708E)
This circuit was found in a 90s Popular Electronics. It can be used to control a triac from the...
Flasher (CB22498E)
Originally designed for an incandescent lamp, this flasher or pulser can be adapted to operate with...
Simple Metal Detector (CB11508E)
This circuit found in Popular Electronics from July 1974 consists of an oscillator that sends its...