Abstract: A line pair testing and fault diagnostic apparatus implementing three-terminal measurement techniques using a multiple frequency source waveform transmission to propagate a reflected waveform. The apparatus implements a microcomputer circuit executing a program. The program has frequency domain analysis algorithms to process the reflected waveform to provide a craftsperson with the electrical characteristic data of a line pair to inform the craftsperson the existence of a line pair fault and the location of the fault in the line pair. The apparatus implements relays for switching between several diagnostics circuits within the apparatus for providing the craftsperson with numerous methods and techniques for troubleshooting a line pair.

Abstract: A line pair testing and fault diagnostic apparatus implementing three-terminal measurement techniques using a multiple frequency source waveform transmission to propagate a reflected waveform. The apparatus implements a microcomputer circuit executing a program. The program has frequency domain analysis algorithms to process the reflected waveform to provide a craftsperson with the electrical characteristic data of a line pair to inform the craftsperson the existence of a line pair fault and the location of the fault in the line pair. The apparatus implements relays for switching between several diagnostics circuits within the apparatus for providing the craftsperson with numerous methods and techniques for troubleshooting a line pair.

Abstract: Disclosed is a self-contained battery powered remotely controlled strapping and interconnection device for providing various selected interconnections and terminations of telephone lines or line pairs to which it is attached in order to establish testing configurations comprising a plurality of multi-contact latching relays selectably operable through a plurality of shift register devices under the control of an on-board processor responsive to dual tone multi-frequency instructional command signals remotely applied to a pair of lines. Plug-in expansion modules and battery charger modules are provided.

Abstract: Disclosed is a telephone line testing device comprising: clip leads for connecting the device to "ring," "tip" and external ground lines of the telephone line to be tested. Terminal pads make "ring" and "tip" connections to a craft telephone and a first testing circuit connectable to receive DC signals from the "ring" and the "tip" lines to provide electrical signals indicative of the magnitude of direct current available from the lines. Another testing circuit is connectable to receive AC signals from the "ring" and the "tip" lines to provide electrical signals indicative of the signal loss of the lines. A third testing circuit is connectable to receive AC signals selectably either from the "tip" and the "ring" connections or from the "tip" and the external ground connections comprising a filter and amplifier to receive and treat the AC signals and to apply the treated signals to the input of the second testing circuit.