Relaxation oscillator using a Thyratron (T426E)

This oscillating circuit for a frequency of 588 KHz was found in a book on electronic designs with modern tubes.

12 V to 220 V converter 555 (CB17238E)
The power of this converter is not the greatest, it can only supply small fluorescent lamps,...
Battery Charger with the TL317M II (CB1247E)
This circuit is in the very datasheet of Texas Instruments that manufactures the component...
Remote control tester (CB7819E)
Found in a PE Hobbyst Handbook from 1991, this circuit uses a common photocell as a sensor. The...