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.
We find this circuit in a 2005 Linear Technology manual. The circuit applies to small DC motors...
This 12V battery charging circuit automatically shuts off at the end of the charge. The disconnect...
This is one of many Morse code audio oscillators that can be found in this section. The circuit...