In this 1990s circuit, found in a National Semiconductor manual, the output voltage is the square of the input voltage. The components are from the period.
This circuit is from 2001 documentation, serving to multiplex stereo signals for FM transmitters. The...
This circuit reverses the signal if both positive and negative. We found it in an American...
Found in a publication by Gernsback from 1960, this circuit makes use of germanium transistors of the time....