Abstract: The invention presented herein is directed to a remotely addressable maintenance unit (RAMU) working in conjunction with a test head at the central office for detecting and locating faults in digital subscriber loop (DSL) and/or plain old telephone system (POTS) environments. The RAMU includes circuitry for setting and resetting one or more relays for either normal or testing/maintenance mode. The present invention provides a system and method for addressing the RAMU by applying either positive or negative voltages from the tip to ground, from ring to ground, and from tip and ring to ground. In this manner, individual RAMUs can be defined/designed to respond in certain voltage levels and polarities. Accurate fault detection and sectionalization is achieved by the combination of the addressing capabilities enumerated herein, and the impedance signature designed into the RAMU, working in concert with a test head in the central office.

Abstract: A subscriber circuit allowing a reliable and proper subscriber line test is disclosed. The subscriber circuit includes a splitter and a feeder for feeding a current to subscriber equipment through a subscriber line. A path selector is provided to select one of a first path and a second path between the subscriber line and the feeder. The first path has the splitter inserted therein and the second path has no splitter inserted therein. The path selector normally selects the first path. When the subscriber line test instruction is received, the path selector selects the second path.

Abstract: A remote telephone testing device (22) includes a transmitter (30), a receiver (24), a controller (26) and a test circuit (28). In response to the receiver (24) receiving a test signal from a test system (20) via a telephone network (2, 4, 6, 8), the controller (26) communicatively isolates telephone equipment (10) of a subscriber (S) from the telephone network (2, 4, 6, 8) and connects the test circuit (28) to the telephone equipment (10). The test circuit (28) tests the telephone equipment (10) and conveys one or more results of such test to the controller (26) which relays the one or more results to the test system (20) via the transmitter (30). When testing is complete, the telephone equipment (10) is isolated from the test circuit (28) and is communicatively connected to the telephone network (2, 4, 6, 8).

Abstract: A communications system is tested to simulate a realistic conversation. A first measurement device make a call, through the system it is testing, to a second measurement device and the two devices converse using predetermined speech generated dynamically by each device in response to the signals received from the other, to simulate aspects of conversation over non-perfect communications system link. The progress of the conversation will therefore take different courses according to the quality of the link. For example, if an expected signal is detected by one device, it transmits an appropriate predetermined response to the other device. However, if the expected signal is corrupted, or not received at all, different predetermined responses (or no response at all) are transmitted to the other device. This in turn may cause the other device to repeat the original signal.

Abstract: A testing system for voice system equipment in a switchboard includes a testing maintenance terminal for inputting telephone number information of an ordinary subscriber's telephone that is to be designated as a maintenance party telephone. The testing maintenance terminal can be a testing maintenance terminal of a general-purpose information processing unit. A call processing block inside a control unit of the switchboard includes a test accepting module for accepting the telephone number information from the testing maintenance terminal and for transmitting a call message to a call control module, in addition to the call control module and a translation module.

Abstract: A method and apparatus for testing network elements within a communications system. A test is initiated at a data processing system located at a first site by the selection of one or more network elements for testing. In initiating the test, a communications link is established between the data processing system located at the first site and a network element located at a second site. The network element is monitored during testing of the network element using the communications link. The information is displayed on the data processing system in the form of a web page. Monitoring of the network element is paused from the data processing system in response to detecting an error originating from the network element. Monitoring of the network element is restarted from the data processing system in response to a correction of the error.

Abstract: A system and method to detect ground faults in a multi-processor communication system that includes a communications link that extends between the processors. The processors isolate different sections of the link. Measurements made with different isolated sections establish the location of the fault. The processors can also make measurements of the link to establish the magnitude of a shunt impedance on the link. Where an abnormal value of shunt impedance is detected, the respective devices can activate or deactivate solid state isolation circuitry to disconnect a section of the link exhibiting the abnormal level of shunt impedance.

Abstract: A two-ended, line-driving and receiving/tone signal analysis system performs line connection verification applying a low-distortion, low-amplitude test signal to one end of a cable pair under test and monitoring the response of a remote end wireline pair. Preferably the test signal frequency is on the order of 110 Hz, which avoids domestic and foreign AC power signal frequencies and is spectrally equidistant from their harmonics. It also avoids ringing frequencies for POTS lines, and remains safely below the 350 Hz lower limit of POTS and other telephone line system services. In response to application of the 110 Hz test signal to tip and ring segments of a wireline pair at one end of the cable bundle, the energy of the 110 Hz component, as well as that of two other ‘spectrally nearby’ (slightly higher at 112 Hz and slightly lower at 108 Hz), are measured at a tip and ring pair at the far end of the cable plant.

Abstract: A testing environment and a method for telephone number identification and/or verification. The method identifies a telephone number associated with a tested telephone line by: (a) operatively connecting a test equipment to the tested telephone line; (b) dialing via a communication port of the test equipment, via the tested telephone line, via a cellular communication system, to a cellular receiver, and (c) processing a received signal received by the cellular receiver to identify the telephone number associated with the tested telephone line.