We found this parallel regulator in a 1973 publication. Transistors admit equivalents and the output voltage can be modified by changing the zener.
This circuit was found in an American documentation from 1968. The circuit uses transistors from that...
Found in the June 1962 Radio Electronics magazine, this circuit uses 4 transistors. The range...
We found this circuit in Popular Electronics from 1993. The circuit can be assembled with any...