Patent · US Expired

Testing of subscriber loop pair gain systems

US4270030A · kind A · utility

23Cited by
7References
21Claims
0Family size

Assignee

Inventors

Key dates

Filing dateNov 27, 1979
Grant dateMay 26, 1981
Priority date
Expiry dateNov 27, 1999

Classification

  • Technology area (CPC H)Electricity
  • CPC primaryH04M3/30
  • WIPO fieldTelecommunications
  • WIPO sectorElectrical engineering

Abstract

A testing system is disclosed for telephone subscriber loops which are in part derived by multiplex facilities in what have come to be known as pair gain systems. In this testing arrangement, the local drop wires from the remote terminal of the pair gain system to the subscriber are separated from the carrier system itself and tested by connecting them to a separate metallic pair extending from the central office to the remote terminal location. Simultaneously, the carrier-derived portion of the subscriber loop is connected to automatic testing apparatus which sequences through a plurality of automatic tests for not only transmission characteristics of the carrier-derived channel but also tests for the ability of the derived channel to transmit supervisory information such as ringing, coin control and party identification information. The remote terminal of the pair gain channel is selectively terminated by a reflective or absorptive termination to assist in these testing procedures. The testing system is designed so as to make carrier-derived channels appear to the central office testing personnel as if they were identical to metallic loops, thus saving considerable administrative…

Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.