Suggested by a 1965 Electronic Design, this circuit has a gain of 15 dB at 45 MHz and can be changed to operate on other frequencies. The tetrode FET is an uncommon component today.
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...