This circuit was obtained from American documentation from 1966. It triggers when the two input voltages are within a pre-established range. The circuit can be mounted with modern transistors.
This voltage calibrator circuit using a zener diode was found in Radio Electronics magazine from...
The relay of this circuit closes when the position set in P2 is reached by the sensor...
The purpose of this circuit, which we find in an old American documentation, is to allow the...