| 摘要 |
PURPOSE:To prevent line holding by not only transmitting a pilot signal to a slave station of the other party but also receiving the pilot signal from the slave station of the other party and releasing a line at the time of not receiving the pilot signal over a certain time. CONSTITUTION:If line disconnection occurs in a satellite line 81 in the middle of speaking, the pilot signal is not received for 60 seconds of the prescribed time or longer by a slave station 31, and time-out is detected by a timer 36. Then, the slave station 31 judges the line 81 to be faulty and releases the line 81 to perform the trouble processing and transmits a release end signal to a master station 2 through a control line 7. The master station 2 receives this signal to return a release confirmation signal to the slave station 31 and handles the line 81 as a faulty line. Meanwhile, a slave station 3n detects time-out by the timer 36 to release the line 81 and performs the trouble processing and transmits the release end signal to the master station 2, and the master station 2 returns the release confirmation signal to the slave station 3n. Thus, ineffective line holding for the occurrence of trouble of each slave station is prevented. |
