Multi-stage amplifier device

PURPOSE: To properly send an external output signal to a post-stage base station even when a power supply device is faulty by providing each means applying bypass control to a relay amplifier when a fault of supply power to the relay amplifier of each base station is detected. CONSTITUTION: n-Sets (a-n) of base stations connected in cascade and equipments in each station are all identical, and the base station and its equipment are described in (a). Each base station 20a receives an external output signal of a central managing room and a base station, is signal is amplified by amplifiers 14a, 15a and outputted to a pre-stage and a post-stage. A power supply device 16a supplies power to the amplifiers 14a, 15a and the supplied power is detected by a power detection relay 21a and when it is detected to be a fault as the result of detection, a relay 21a is activated. Thus, control contacts 22a, 23a, 24a, 25a are connected from the amplifiers 14a, 15a to the bypasses 26a, 27a. Thus, even when the device 16a is faulty or the like, an external output signal is properly sent to a pre-stage and post-stage central managing room and a base station. COPYRIGHT: (C)1993,JPO&Japio