INDUCTION LINE DISCONNECTION DETECTION DEVICE AND METHOD, AND RADIO REBROADCAST SYSTEM

摘要

PROBLEM TO BE SOLVED: To detect disconnection of an induction line which transmits AC signals and to prevent a minus ion from being drawn toward the induction line for prevention of rust by applying the minus DC voltage to the induction line with the ground side made a plus side and detecting the potential set between the induction line and the ground. SOLUTION: The radio broadcast signals received via an AM antenna are received by an AM receiving rack and turned into the sound signals. These sound signals are turned again into the original frequency signals by an AM broadcast rack and outputted via an induction line set in a tunnel. Thus, an AM receiver can operate in the tunnel. Meanwhile, an induction line disconnection detection unit 21 applies the minus DC voltage to the induction line with the ground side defined as a plus side. Then a detection part 25 of the unit 21 detects the potential set between the induction line and the ground and then detects the disconnection of the induction line based on the detected potential. Otherwise, the part 25 detects the current of the induction line and decides the disconnection of the induction line based on the detected current. When the part 25 decides the disconnection of the induction line, the part 25 sends a signal to a notification means 26 to notify the disconnection in sounds, the light display, etc.