This receiver was found in a 1924 book by Gernsback. The circuit uses three tubes and is powered by 3 batteries of different voltages, common at the time.
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...