Found in a 1968 Motorola documentation, this circuit operates at 1 kHz and can deliver 20 V from 12 V. Transistors support modern equivalents.
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...