This circuit was found in a documentation for radio amateurs from the year 70. Its purpose is to produce a tone on a transducer when transmitting messages in SSB telegraphy.
This circuit is an excellent shield for microcontrollers and was found in the October 1987 Radio...
We found this circuit in a 1981 publication, when it was still possible to find 22.5 V batteries (used...
This grid-dip meter was found in a 1956 documentation from Sylvania. It can be implemented with...