| 摘要 |
PURPOSE:To facilitate the supervision and maintenance and operation even when the number of slave stations is increased by supervising transmission power, transmission frequency and the fluctuation of a transmission frequency band width from each slave station, detecting a station whose level is changed by a prescribed level or above, specifying the station and issuing an alarm. CONSTITUTION:When a frequency out of the standard and excess transmission power are sent from a station among slave stations 5, an alarm detector 2 mounted on a supervisory and controlling circuit 1 from the output IF signal (a) of a transmitter-receiver 7 detect then. A decoder 3 decodes in which slave station the abnormality takes place depending on a detected alarm signal (b) and the IF signal (a) and the result is displayed on a display device 4 as a data signal (c). Thus, which slave station 5 has a fault is supervised centralizingly at a master station and the supervision and maintenance and operation are facilitated even when the number of slave stations is increased. |
