This circuit, for frequencies up to 100 kHz, was found in American documentation from 1970. The circuit can serve as a reference for projects with modern equivalent components.
In the figure we have a Texas Instruments circuit for TTL interfacing using discrete transistors. The two...
This circuit was found in Radio Electronics magazine from June 1963. The range is small and the...
The project presented in a 2009 documentation is intended for radio amateurs operating in the...