| 摘要 |
PURPOSE:To make it possible that different kinds of exchanges use as a subscriber's tester, by connecting a boost power source to the subscriber's line when the current flowed out to the subscriber's line is smaller than a certain value. CONSTITUTION:When a subscriber's telephone set 4 is connected, a line monitor relay A is operated. Then, a controlling part 9 operates a relay INT to perform a series of tests successively. Meanwhile, when a long-distance subscriber's telephone is connected, the line monitor relay A is not operated, and a line length detecting means 7 detects that the current flowed to the subscriber's line is smaller than a certain value, and the means 7 sends the detection signal to the controlling part 9. The controlling part 9 operates a relay LL to connect a boost power source BB to the subscriber's line. As the result, the line monitor relay A is operated, and hereafter, tests are executed similarly to the general subscriber. |
