Found in a 90s Elektor, this mixer makes use of integrated circuits of the time. The supply must be symmetrical at 15 V.
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...