This circuit converts signals from the shortwave band to the 118 to 130 MHz VHF band used in aviation. The circuit uses a 55 MHz crystal. We found it in documentation from the 90s.
The circuit shown is from an old European publication. In it we have the way to activate a relay...
We found this circuit in a European publication from the 1990s. Transistors are still common types...
This circuit was found in an American documentation and can be added to common amplifiers of any...