This small regulated power supply was found in a 1963 General Electric documentation. The special zener diode transistor can be replaced with an equivalent discrete configuration.
This circuit was published in an English magazine from 1981, but it can be easily assembled today,...
This circuit was obtained in the publication 101 Electronics Projects of 1979. The circuit can be...
Using JFETs, this circuit from a 90’s American documentation can generate signals of 0.15 Hz. The...