| 摘要 |
PURPOSE:To enable to achieve the communication line among the slave stations of multi-direction and multiplex line without using complicated means, with a simple constitution, and without lowering the communication level and increase in the side tone, by means of a simple operation. CONSTITUTION:In the multi-direction and multiplex radio line connecting the master station 1 and a plurality of slave stations 2-1 to 2-n via radio lines, the first and second communication circuits 7-1 and 7-2, and reception circuits 8-1 and 8-2 are provided at the master station 1 and the slave stations 2-1 to 2-n respectively. Further, the master station 1 and the slave stations 2-1 to 2-n are provided with the band pass filters LPF 13-1 and 13-2, and the slave stations 2-1 to 2-n are provided with the signal oscillator 14 and the signal receiver 15. Moreover, out of the band of the communication lines 7-1 and 7-2, the out of band signal is provided to every direction, a slave station of the stations 2-1 to 2-n calling communication feeds information to the master station 1 with this signal, and the master station 1 returns the out of band signal. Further, the stations out of calling and other stations receive the out of band signal of the master station 1, allowing to automatically select them to the communication lines not connected with the calling station. |
