This circuit was found in a 303 Circuits issue of Elektor magazine from the 1990s. The circuit uses an equivalent operating system. The source is not symmetrical.
Constant currents from 10 mA to 1 A can supply the load, depending on the selection made by S1. Q1...
In the figure we have two typical configurations of voltage regulators with protection against short...
Found in an old Radio Electronics, this circuit uses current components, used to rectify AC...