This circuit converts infrared pulses into audio and can be used in an experimental telegraphic link. The circuit is from a Popular Electronics from the 90s.
We found this circuit in a 1985 technical publication. The circuit uses PUTs to drive lamps....
This precision circuit can be implemented with other operational ones. We found it in a...
This simple circuit uses a car ignition coil. The circuit appeared in the 1983 Radio Electronics Annual...