| 摘要 |
PURPOSE:To easily recognize the presence of connection by detecting the presence of connection between an antenna and a reception circuit so as to issue alarm when they are disconnected from each other. CONSTITUTION:When a plug 4 is not plugged into a jack 17 in at least one of connectors 16, 18, a discrimination circuit 19 outputs an output signal and the disconnecting state of the plug 4 and the jack 17 is displayed on a display device 20 thereby easily recognizing the disconnection. |
