Integrator with JFET (CB6229E)

This circuit was found in an 80s National Semiconductor documentation. The configuration holds true for modern JFETs.

LM3914 Audio Indicator (CB24686E)
This is one of many possible circuits for the LM3914 IC as an audio indicator. The trim pot has...
Isolated zero-crossing switch (CB7419E)
This circuit was obtained in a General Electric documentation from the 80's, and can be used as a...
Current Controlled Oscillator (CB13512E)
This circuit was found in a 1973 publication. The operational ones can be exchanged for...