Found in a Philips documentation from 1968, this circuit detects the trimpot set input voltage. The operational can be of almost any kind.
Several types of OSEPP sensor modules can be obtained from Mouser Electronics for Arduino...
Epcos TDK TB2569 Film Capacitor EPCOS / TDK offers through Mouser Electronics are line of film...
This circuit was obtained from a 2005 Linear Technology application manual. The circuit is...