This circuit is from 1964 documentation but can be easily implemented based on current components. Input waveforms and detection are shown next to the diagram.
This control circuit or reversible contactor was found in a 1967 General Electric manual. The...
This is one of the many versions of amplifiers with LM386. This was achieved in an old publication (1981). The...
This two-phase stepper motor circuit was found in an old documentation using an operational amplifier...