This circuit visually indicates that a high voltage is present in an outlet or other point. The neon lamp is common, and the appearance of the assembly is suggested in the same figure.
This common gate circuit for the 13 to 30 MHz band was found in old English documentation....
This circuit was originally found in a Philips documentation from 1969. It is intended for sensing...
This FET voltmeter is from an old 1974 amateur radio publication. The circuit can use MPF102 or...