This differential pulse shaping amplifier was found in documentation from the 1980s. Switching transistors equivalent to the originals can be used.
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....