This circuit was found in a 1945 publication. The circuit was stated to be part of a walk talkie. Note that, as it is a portable assembly, it was powered by batteries. The jack was for microphone insertion.
Found in Unitrode documentation from the 1980s, this circuit makes use of PUTs, currently common...
This bidirectional motor control was found in an 80's Electronic Engineering. The circuit uses a...
We found this circuit in the 1972 RCA Linear Integrated Circuits Manual. The circuit can generate...