| 摘要 |
PURPOSE:To interchange signals economically by limiting the use of a network unit, by making it possible to repeat line signals by making a connection between calling trunks as to only a signal converting trunk. CONSTITUTION:State supervisory relay F supervises the blocking of a next stage and sends a blocking state signal to a preceding office. The start signals of the preceding office operates relay A to transmit trunk start information to central processor via scanner SCN, and processor CC acquires free incoming register trunk IRT to connect a signal converting trunk to IRT, thereby receiving the register signal of the preceding office. Once IRT receives the register signal, processor CC acquires free outgoing sender trunk OST to connect the signal converting trunk to OST. On the other hand, when the transmission of the register signal from OST to the next office ends, processor CC releases OST and a network to return the signal converting trunk to a speech state. Once a called subscriber answers, reverse signals of line A and B are sent back to operate relay F. The signal converting trunk informs the processor CC of the answer of the called subscriber by way of SCN. |
