Virtually any FET can be used on this voltmeter found in old documentation. The indicator is a microamper meter 0-100 uA and the accuracy of the circuit depends on the accuracy of the resistors used.
This circuit was found in the February 1980 issue of Radio Electronics magazine. The digital...
We found this circuit in a Motorola manual. The circuit has the capacitor charging at 15 to 30 V,...
This circuit has a high input impedance and low output impedance, serving as an adapter for...