| 摘要 |
PURPOSE:To make the tripartite two-way service possible, by using a hybrid coil in the offering trunk of a four-wire exchange. CONSTITUTION:In a four-wire exchange having channels T (transmission) and R (reception), hybrid coils HYBA and HYBB are provided in an offering trunk OFFT. When a subscriber C breaks in between speaking subscribers A and B, subscribers A, B, and C speak to one another in two directions through a four- wire trunk A, a trunk B, and the offering trunk OFFT. |
