This circuit is from an American 1964 documentation. Transistors of the time are used, but modern equivalents can be employed.
This very low ripple and high voltage circuit was found in a technical documentation from the 70s,...
This circuit is from the book Fun Projects for the Experimenter by Newton C. Braga, published in...
This circuit converts a positive CMOS supply voltage to a negative one. We found it in a 90s...