This proximity relay circuit was found in the July 1990 Radio Electronics magazine. The supply voltage should be according to the relay used.
Found in an Electronic Design from the 90s, this circuit does not need sinks for its components. The...
The figure shows a way to apply gain control to the LM3600 OTA. The circuit is from a Radio...
This circuit was found in a 1968’s General Electric documentation. The circuit has a control range of...