Abstract: Monitoring system particularly for detecting the presence of moving persons in a monitored area.This system comprises two detection stages 2 and 22, two processing stages 3 and 23 and a selective switching-on stage 4 which the two groups of stages 2, 22 and 3, 23 have in common. Each one of the detection stages 2 and 22, which comprise cameras 7 and 27, respectively, send field signals to the associated processing stages, these signals corresponding with the observed images. Each processing stage sequentially compares the signal values in the field signals which the stage receives in accordance with a controllable pre-determined rhythm, whereafter it sends comparison signals, whose number is proportional to the magnitude of the observed motion by comparing the field signals, to the switching-on stage 4. When the sum of the two numbers of signals received by the switching-on stage 4 is greater than the threshold value present in the threshold circuit an intervention device 17 is actuated.

Abstract: A device for the acquisition and storage of an electrical signal.The signal is divided into adjoining elementary time intervals of specific duration. During each of them the amplitude minimum and amplitude maximum of the signal are established, which values are first stored in analog form and subsequently in digital form.The device may be utilized in oscilloscopes, in particular those of the type comprising a matrix display panel.