| 摘要 |
<p>PURPOSE:To reduce the number of supervising lines between a relay station and a central terminal station where the supervising lines are branched by providing a line selection switch to each branched relay station where the supervising lines are branched and changing over the branched lines by the said switch when the supervision and troubleshooting are performed for devices of a relay station far from the branched relay station. CONSTITUTION:A fixed pattern signal for measuring code error transmitted from a central radio terminal station 1 passes through a radio relay station 2 and is branched into two at a hybrid circuit 13 of a branch line selection switch at a branched radio relay station 3'; one passes through a radio relay station 4, is reflected at a radio relay station 5 and passes through the radio relay station 4 and reaches the branched radio relay station 3', and the other passes through a radio relay station 6, is reflected at a radio relay station 7, passes through the radio relay station 6 and reaches the branched radio relay station 3'. The branched line selection switch 13 of the branched radio relay station 3' is changed over to the position in solid lines by the control of the radio centeral terminal station 1. Thus, the fixed pattern signal from the radio relay station 4 and the fixed pattern signal from the radio relay station 6 pass through the radio relay station 2 on the same supervising line and reach the radio central terminal station 1.</p> |
