This oscillator produces a modulated signal using a unijunction transistor. We found it in an American documentation from 1965. The circuit modulates in frequency the generated signal.
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...