This simple low current circuit was found in a Radio Electronics magazine from August 1960. The circuit does not use transistors in regulation, but only zeners directly.
The battery charger suggested in the figure has its current limited by resistor R1. This component may...
This interesting 80's EDN circuit divides the input pulse frequency by a number given by n...
This circuit was found in a 1969 CQ magazine. It is intended for coupling telephones to radio...