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.
We present a circuit formed by six voltage comparators. Each comparator will analyze the voltage...
This circuit can generate time base signals from 5 to 1500 Hz. We find it in a documentation about old neon...
In this circuit the CA3140, an operational amplifier, is used as a comparator with the zener diode...