| 摘要 |
PURPOSE:To transmit the inversion signal to the calling subscriber with no intervention of the control part and no use of the relay driving unit. CONSTITUTION:Answer monitor relays A and D are actuated by the subscriber loop when subscribers subA and subB are under the answer state. And the circuit is formed via diode Di and coil B at intra-office trunk IOT, and reversing relay B operates. Thus the direction reverses for the direct current of subA, and reverse signal is transmitted to the calling subscriber only in case the both subscriber give the answer. And the reverse state has no change although one of the subscribers cuts the loop under talking, and relay B has no operation even if the subscriber abandons his rights prior to connection to IOT. At the same time, relays A and D repeat action and non-action when the subscriber has the hooking action, and scanner SCN operates regardless of relay B. In such way, an automatic reversing function is secured for the intra-office trunk by the answer of the subscriber. |
