This circuit appears at various points on this site and in this section and can be designed with almost any operational amplifier. This version is from an American documentation from 1975.
We found this circuit in a 1985 technical publication. The circuit uses PUTs to drive lamps....
This high-powered megaphone circuit is from a Radio Electronics from December 1964. Note the use...
This amplifier with differential input uses two old op amps but can be implemented with modern op amps....