3-way control (CB7047E)

This is a simple circuit to control a set of lamps from 3 different points. We found it in an old Popular Electronics.

Optical zero-crossing switch (CB7416E)
This normally open, two-terminal, high-sensitivity circuit was found in General Electric's...
Bubba Oscillator (CB12743E)
Bubba's oscillator, shown in the figure, is another type of phase shift oscillator, but it takes...
MOSFET Electroscope 3N128 (CB852E)
This sensitive electroscope uses a MOSFET 3N128 and can detect electrostatic charges of objects....