| 摘要 |
PURPOSE:To connect easily plural slave machines to one master machine by providing the slave machine with a signal separating means which separates a control signal from an input means and a sound signal from a speaking means and takes out them and connecting master and slave machines through control lines for individual signals and a voice line. CONSTITUTION:When a call switch 30 of a slave machine E is inputted, a call switch signal is inputted to a communication control circuit 50 through a detecting terminal 40 and is transmitted to a communication control circuit 49 of a master machine D through a control line 53. The communication control circuit 49 drives a ringing tone generating circuit 47 to generate the ringing tone from a speaker 45 through a voice switching circuit 44. When detecting that a hand set is taken off from a hook switch 48, the master machine D transmits a voice line connecting command to the communication control circuit 50 of the slave machine E through the control line 53 and stops the ringing tone generating circuit 47 and connects a relay 43 to switch the voice switching circuit 44 to the side of an audio line 52. Meanwhile, the communication control circuit 50 connects the relay 43 when receiving the voice line connecting command, and the service is started. |
