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 circuit came out in an American magazine that no longer exists. It's the Electronic...
This circuit originally came out in a Budget Electronics from 1981. The American magazine no...
This is the traditional audio preamp configuration with the National Semiconductor LM382. The...