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.
This circuit is from a Popular Electronics of the 90's. Any power MOSFET can be used. The circuit...
This circuit was obtained in an American publication of 1977. The circuit generates rectangular...
We found this circuit in a publication of 1990. With the changes it can be mounted easily today....