| 摘要 |
PURPOSE:To avoid the interference between terminal devices and to extend branch lines, by connecting a base band MODEM to one set of MODEM connected to a line and branching a plurality of terminal devices via the base band MODEM. CONSTITUTION:Under the control of a central control station 1, a specific terminal device is called out, and information is given and received via a line between the device and the control station 1. In this case, a base band MODEM 3 is connected to a single MODEM 2 connected to the line and a plurality of terminals are branched via the MODEM 3. Then, a base band signal transmission is performed between the MODEM 3 and base band MODEMs M1-MN, and the length of metallic wires L0, L1-LN connecting the MODEM 3 and the MODEMs can sufficiently be taken longer. |
