| 摘要 |
A subscriber station (20, fig.1) provides a wireless telecommunication link to a remote central station (10). The subscriber station includes a transmitter/receiver (24, fig.2) for communication with the central station and for processing signals for transmission and/or received signals, at least one telephone line (32) for connection to subscriber telecommunications equipment (34,36,38), and a high impedance test circuit 750, comprised of sub-circuits 754,756,758,760,762, which may be connected across either telephone line 726,727 or 728,730 via relay 752. Having a high impedance, the sub-circuits may be permanently connected across the line under test, thereby allowing their connection during all operational conditions of the telephone line. In this way the test circuit is able to provide a range of test functions, including self-test functions in a cost effective manner, which would not be possible with conventional test circuits which are only switched in during line testing. |
