We found this circuit in an old documentation for radio amateurs. The circuit uses an analog indicator. The characteristics of the coils are given next to the diagram.
The PA222 integrated circuit used in this project from an American 1967 documentation is not...
This circuit with an optical path sensor was found in a 1995 documentation. The circuit fires...
This circuit was found in an 80's Electronic Design. It amplifies TTL fast signals for a coaxial...