Found in an old publication about neon lamps this circuit works directly connected to the power grid, serving as an indicator for various situations. Ordinary neon lamps can be used.
This circuit is from a 1995 Electronics Now. It generates a 1 kHz sinusoidal signal. See in the...
Found in a publication by Gernsback from 1960, this circuit uses germanium transistors of the time...
This circuit is based entirely on SCRs. The circuit is from an American 80's documentation; and the PUTs...