This circuit was obtained from 1967 documentation. It uses a sensor to determine the trigger point. The components are of the time, difficulty to obtain these days.
This circuit was found in a Popular Electronics from the 90s. The components used are all common...
This circuit is from a 60's documentation. The circuit uses components from the era and serves to...
One pulse in the output is produce at each 5 pulses applied to the input. The circuit uses CMOS...