| 摘要 |
PURPOSE:To carry out the test of a subscriber circuit regardless of the state of the subscriber circuit to be tested by forming two channels from a test control means to the two exchange interface circuits of a test means for subscriber circuit. CONSTITUTION:When the electrode of a test controller 8 is operated, the test control signals are supplied to terminals 26a and 26b and then to terminals 27a and 27b of a subscriber circuit test instrument 24 through two channels. These control signals are received by a signal receiver 14 via the terminals 27a and 27b. Then a control circuit 11 actuates a relay 17 and leads a subscriber to be tested to a measurement circuit 12 for execution of the test. When this test is over, the test result is sent back to the controller 8 by a signal transmit ter 15 via terminals 26a and 26b. When a maintenance operator talks with the subscriber to be tested, the relay 17 is restored and a relay 25 works. Thus a channel is formed within the instrument 24. A relay 16 connected to a call line monitors the state of said subscriber. The circuit 11 can know the state of the subscriber through a contact 16a. |
