Abstract: A processor-controlled integrated telephone line measurement and conditioning apparatus installable at a remote site provides a multiplicity of measurement and conditioning functions that are selectively executable in response to commands issued from a supervisory command site. The dual measurement and conditioning capabilities of the architecture of the present invention impart both remote measurement unit (RMU) functionality and metallic access unit (MAU) functionality that may be individually accessed and controlled. The RMU operates primarily as a test head that performs mechanized loop testing (MLT) tasks, while the MAU is operative to impart prescribed electrical conditions to a specified line circuit. When controllably accessed to operate as an RMU, the present invention responds to instructions from a command site (loop maintenance operations systems) and performs single-line demand tests on a line provided by a pair gain system.

Abstract: A data communication and sleeve lead control apparatus provides auxilary signalling between a no-test trunk control unit, and another unit such as a pair gain unit which is coupled with the link between the control unit and the no-test trunk, while maintaining stability of the sleeve lead monitored by the no-test trunk. The appearance is installed within the pair gain unit, and effectively isolates the sleeve lead to the no-test trunk from sleeve lead to the no-test trunk control unit, so that the data communications between the control unit and the pair gain unit are transparent to the no-test trunk. During a prescribed sleeve lead current flow state, e.g. high resistance or low current flow, controlled interruption of sleeve lead current between the control unit and the pair gain unit effectively modulates the state of the sleeve lead therebetween, but does not change the intended current flow state applied by way of the sleeve lead output port to the no-test trunk.

Abstract: A direct access test unit for testing subscriber lines is located in the central office and is accessable from a remote location through a standard ground start line circuit. The field technician involved in a troubleshooting problem dials the number of the ground start line circuit followed by a security code to gain access to the test unit which then returns dial tone. Dialing the number of a subscriber line to be tested provides for access to that line via the test unit and a test trunk connected thereto. Various tests may be performed on the subscriber line thus accessed by dialing a selected digit to identify the test. The test unit provides voice messages to the field technician to instruct in the use of the test unit and explain the available test operations and how they may be initiated.