| 摘要 |
PURPOSE:To transmit a signal before hitting to a line E for the hit <=nearly 0.6sec by integrating a signal to the line E detected from a transmission line by a transmission terminal station device at all times and transmitting the integration output to the line E at the detection of hit of the transmission line. CONSTITUTION:A signal from a synchronizing circuit 22 is at logical 1 level normally at, e.g., a PCM 24 CH multiplex transmission terminal station device and voltage to the E line 10 at a point C of each CH of an output of a signal separating section 15-2 passes through an AND circuit 17 and an OR circuit 20, is converted into an exchange interface level by a level converter 21 and transmitted to an exchange 5 via the E line 10. If a hit of nearly 0.6sec takes place in the transmission line during talking, out of synchronism is detected, and an out of synchronism detecting signal of 0 level is outputted from the circuit 22, the circuit 17 is closed, 1-level is inputted to an AND circuit 18 via a NOT circuit 19, the signal (d) from an integration circuit 16 enters a converter 21 through the circuits 18, 20 so as to hole the state before hitting. |
