Found in a Popular Electronics from the 90s, this circuit can be adapted to use modern operational amplifiers. The output voltage is the square root of the input voltage.
This circuit, from an 80's publication, detects the SCA (Announcer Eliminator) signal from FM...
The circuit is from the Linear Application Handbook. The resistors determine the voltage applied to...
USB58xx and USB59xx Devices Integrate a 2:1 Multiplexer to Support Reversible Connection of USB...