| 摘要 |
PURPOSE:To detect exactly the collision of calls by detecting whether the other station side sends out a start-of-pulsing signal to the own station side or not, during a period for senting out the start-of-pulsing signal transmitted after transmitting a actuating signal of the own station side exchange device. CONSTITUTION:When a seizing signal is sent out to a B station from an A station, an MF (multi-frequency) signal receiver MFR is connected to a receiving side path of a bothway circuit BWT by switching a switch NW. In case when a collision of a call is generated, a start-of-pulsing signal KPB sent out to the A station from the B station is received, and the collision of the call is detected. When the collision of the call is detected, the A station sends out the start-of- pulsing signal KPA by a time when the B station can receive completely the start-of-pulsing signal. Thereafter, the A station sends out a busy tone by switching the NW, and releases the circuit. In this way, a bothway circuit is constituted by discriminating a start confirming signal from the B station, from the actuating signal, and detecting exactly a collision of a call, and an economization is improved. |
