We found this circuit in an American documentation from 1969. The circuit works with the polarized transistor in reverse in the avalanche mode.
The frequency of this circuit depends on C1 and, for the indicated values, it is 1 kHz. Equivalent...
This configuration with the LM383 appears elsewhere on this site. The circuit shown was obtained...
This circuit was obtained from HAM Radio magazine in an 80's issue. The FETs are types of the time...