| 摘要 |
PURPOSE:To make it possible to use two circuits independently by making a switching connection between two circuits by one duplexer normally and then by using a stand-by duplexer inserted into a jack provided to one circuit at the time of call convergence. CONSTITUTION:When a signal from either communication circuit 1 or 2 is inputted in normal mode, duplexer 11 is connected by switching to the communication circuit by incoming display of incoming display unit 3 or 4. Here, since one duplexer 11 is shared, the input of a signal from the unused communication circuit results in that the communication circuit is not constituted. In case of call convergence like this, switchs 5 and 6 are switched to the communication circuit 2 side and a stand-by duplexer is inserted into jack 7 provided to this circuit. At this time, contacts 9 and 10 of relay 8 operate through the operation of relay 8 to constitute a talking circuit between communication circuit 1 and duplexer 11 and that between communication circuit 2 and the stand-by duplexer, so that two communication circuits can be used independently. |
