This fuzz effect for guitars was found in an American 1980s documentation. The transistors may be the BC549 and should be battery powered for noise sensitivity. Diodes are commonly used.
This integrated generates all the higher octave frequencies of a common keyboard when a clock...
In the figure we have the way to make the three-phase control of a motor using opto-diacs. The circuit is...
This experimental short-range transmitter came out in a 1972 publication and was designed to...