Found in a Westinghouse Silicon Power Handbook from the 60s, this circuit makes use of period components. Special high voltage transistors are used. Zeners are 15 V.
This flasher was found in an 80's Electronic Engineering but can be easily implemented with modern...
This simple reducer can supply devices that require currents up to 1 A. The power transistor must be...
This interesting circuit converts BCD signals into a voltage that can be used in an analog...