This small phonographic amplifier was found in a 1967 General Electric documentation. The integrated circuit is from that time, providing 1.5 W of output power.
This is an old test circuit for integrated TTL counters, feeding a Nixie tube, common at the time....
I found this circuit in an Electronics Handbook from 1989. The circuit can be assembled with a...
This circuit makes use of a 2N301 germanium power transistor. We found it in a documentation from...