Patent · US Expired

Trunk test circuit

US4247742A · kind A · utility

3Cited by
6References
14Claims
0Family size

Assignee

Inventor

Key dates

Filing dateSep 26, 1979
Grant dateJan 27, 1981
Priority date
Expiry dateSep 26, 1999

Classification

  • Technology area (CPC H)Electricity
  • CPC primaryH04M3/28
  • WIPO fieldTelecommunications
  • WIPO sectorElectrical engineering

Abstract

A trunk test circuit (107) is disclosed in a stored program controlled toll switching system (103) for executing tests to determine transmission quality of communication trunks connected to a remote telephone office (101). A detector circuit (200) has a novel feedback arrangement comprising a selectable frequency source, comparison circuitry, and a sample and hold circuit, for generating output test signals corresponding to priorly received incoming test signals. The detector circuit is responsive to control signals received from a sequence control circuit (201) for receiving, measuring, and transmitting test signals on a communication trunk (102) under test.

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