OPTICAL AIR POLLUTION OR SMOKE DETECTION APPARATUS OPTICAL AIR POLLUTION OR SMOKE DETECTION APPARATUS

摘要

There is disclosed a control device for use with a light sensing air pollution detection apparatus including an amplifier having pulse amplifiers producing an output pulse of high amplitude, an active peak-detector of high accuracy and linearity over a wide range an an active sample-and-hold circuit associated with a summing amplifier or a microprocessor for detecting and storing the peak amplitude of the pulse, said apparatus adapted to receive and amplify signals received from a solid-state photo-cell to subjected to a flashing light source, the control device including current measuring apparatus such as a moving-coil meter or an LED segmented bargraph display to indicate air pollution and programming pins for tapping off each individual bargraph segment to achieve plural preset alarm thresholds. The flashing light source is monitored to compensate or adjust for variations in flash intensity the signal from the monitor circuit and the detector circuit being subjected to a divider circuit.