Using a 74123 TTL this circuit was found in the Radio Elecronics magazine of June 1975. The power supply must be 5 V. The capacitor determines the activation time.
Found with variations on this site, this circuit was taken from an American documentation from the...
This circuit generates damped sounds imitating a drum or other percussion instrument with...
This is the traditional configuration for a limit comparator or window comparator, using two...