This circuit is from a 1968 Electronic Design. The circuit uses transistors of the time that can be replaced with modern equivalents. More stages can be used to get higher tension.
This 1965 General Electric circuit uses a "Thyrector" that is a suppressor of the time. The...
This circuit allows you to adjust the balance between channels of a stereo amplifier. The circuit...
With this circuit of a Popular Electronics from the 90's it is possible to test a diode with the...