| 摘要 |
PURPOSE:To facilitate part management and repair with parts, which can be used commonly, without special relays, etc., by using commonly the speaker line and the line switch, which have been already provided, when an emergency broadcast equipment is provided newly. CONSTITUTION:Switch 27 is inserted to the service broadcast line which has been already provided, and a line for connecting an emergency equipment newly is inputted to this switch 27, and the line, the broadcast switch, etc., which have been already provided are used as they are by performing switching operation. Therefore, switch 27 is provided with various terminals 28, 30, 33, 34, 36, 39, 40 and 45, and is provided with input switching switch 32 speaker switching switch 38. All speaker lines 37 are controlled in case of emergency use and control circuit 41 is used to use a part of lines 37 selectively in case of partial use. Further, a power source is led from the external, and rectifier circuit 44 is provided. |
