Found in a 1967 Electronic Design, this circuit changes the phase of a signal in 8 different ways, given by the formulas next to the diagram. Equivalent general-purpose transistors can be used.
With this circuit, a relay can be activated from an alternating signal with frequency up to a few...
With this circuit the visually impaired can easily locate important places inside the house, such...
In the figure we have the way to use the transistors of an old-paired pair as a trigger circuit. The...