We found this circuit in documentation from the 1980s. It is an input stage for a digital frequency meter. The circuit can operate with signals up to a few tens of megahertz.
This simple experimental circuit using only transistor produces a tone given by C1 and C2. Tone is...
This circuit, which can be used as a shield, was found in American documentation from the 1970s....
I This well-crafted circuit was found in an American documentation from 1975. The components are...