This is the power step of the previous circuit. Output transistors must be mounted on good heat sinks. The circuit is from documentation from the 60s.
This circuit from the 80s uses an integrated circuit from the time. The CI is difficult to find...
Found in a 90s Popular Electronics, this circuit is intended for amplifying analog video signals....
Suggested by General Electric in a 1967 publication, this circuit makes use of an SCR of the time....