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 for testing zener diodes by lifting their curve on an oscilloscope was presented in...
With this circuit it is possible to obtain a voltage modulated in amplitude with a maximum current of...
This well-known oscillator configuration that produces a siren sound when pressing CH1 is from a...