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.
Found in a publication for radio amateurs from the 1990s, this circuit makes it possible to...
I found this circuit in a Popular Electronics from November 1999. The magazine is no longer...
This simple transistorized receiver with earphone was found in a Japanese publication from the...