This circuit was obtained from a 1967 General Electric manual. The circuit uses components of the time, but equivalents can be used, for example, a BC547 for the transistor and a TIC106 for the SCR.
This circuit was obtained from Popular Electronics of the 1990s. It makes use of a mercury switch that...
I found this circuit in a Popular Electronics from 1992. The circuit shows how we can modulate a lamp...
Found in a 1966 American publication, this circuit invert the phase of a low frequency signal. The...