This circuit was found in a 1967 US publication. In it we have the implementation of a ring counter using only relays. Relay free contacts can trigger indicator lamps or LEDs.
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...