Found in a 90s Radio Electronics, this circuit uses a ceramic capacitor (C1) as a sensor. The operational amplifier is a double 741 of the time.
The circuit shown is from an old English publication from 1965. We can adapt the circuit to work...
If the reader needs to monitor a voltage and does not want an expensive or sophisticated solution. In...
August 2017 - Mouser Electronics is in stock with the PGA460 and PGA460 Q1 ultrasonic processors...