Found in a Philips documentation from 1968, this circuit detects the trimpot set input voltage. The operational can be of almost any kind.
This circuit was obtained from Linear Technology's own component manual of the 1990s. The circuit...
This circuit is suitable for low impedance m icrophones. Gain is given by the 2M2 resistor. This...
This simple circuit applies to any sensitive SCR. We found it in 1982 Maplin documentation. ...