| 摘要 |
<p>PURPOSE:To sufficiently extract the calling characteristic of a telephone set to change due to a calling electric current value by controlling the calling electric current value at a telephone set side based upon the conditions at a trunk line side. CONSTITUTION:A trunk line trapped relay contact 2 is closed, a TDM switch 21 is connected as shown by the broken line of a figure and the control of a calling establishment is completed between a trunk line 1 and a telephone set 61. A trunk line calling electric current is terminated through the trunk line trapped relay contact 2 by a calling electric current terminal circuit 3, detects the trunk line calling electric current value and sends to a CPU 41. The CPU 14 controls so that the calling electric current value to the telephone set 61 can be equal to the trunk line calling electric current value to a calling electric current supplying circuit 38, and the calling electric current value supplied to the telephone set 61 comes to be the same as the calling electric current value of the trunk line 1.</p> |
