APPARATUS FOR REMOTELY MONITORING AND FOR SIGNALLING CHANGES OF STATES OF CYCLICALLY INTERROGATED RECOGNITION FREQUENCY MONITORING TRANSMITTERS

摘要

A rotary switch selects individual incoming transmissions which characterize the actual operation of amplifiers and like components within a data-transmission network. A memory is programmed with data characteristic of incoming transmissions which indicate proper operation of the components actually supervised. As the rotary switch selects an individual transmission, the transmission is interpreted and compared with the data stored in the memory. In the event that a defective component is detected, an alarm sounds and repairs can be quickly made since the individually defective component can be identified automatically.