This circuit was found in an old documentation, being able to generate signals of frequencies in the range of 50 to 100 MHz. The components are of the time.
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...