| 摘要 |
<P>PROBLEM TO BE SOLVED: To change to a standby line by detecting a fault even if broadcast waves stop partially despite no trouble has occurred in a line itself, and to prevent the line from being changed without determining that the partial stop of broadcast waves is abnormal when the broadcast stops even if the broadcast waves stop partially. <P>SOLUTION: When a transmission line 119 is selected from the transmission line 119 and the standby line 146, an input signal from the transmission line 119 is output, and a detector 123 controls switching by a change-over switch 131 based on variations in the output of the input signal from the transmission line 119 and schedule information (transmission presence information). <P>COPYRIGHT: (C)2009,JPO&INPIT |
