This circuit uses components of the time. We found it in a 1968 US documentation. The delay is 100 ns and the input impedance is 1 k.
This circuit generates a siren sound. It was found in the April 1969 Radio Electronics magazine. The...
This circuit converts pulse frequency to current, which is indicated on an analog instrument. The...
This circuit was obtained in a 1991 Electronics Handbook. The publication no longer exists, but...