Visibility measurer with ambient light corrections - has numerical calculators determining visibility from transmission factor

摘要

Electronic circuits are employed which are integrated with the detector to permit an in-situ determination of visibility, taking into account the various characteristics. An analogue signal for the ambient lighting is connected to an input terminal of a validation circuit. A signal representing lighting of a beacon is connected to a second input and the signals are quantified into four levels to validate one of the memories. A transmission factor signal in digital form is connected to the input address highway of a number of memories and causes the validated memory to output the visibility corresponding to the transmission factor given. A digital interface circuit enables signals to be sent to a central control unit.