Patent · US Expired

Subscriber loop feed apparatus

US4197431A · kind A · utility

39Cited by
7References
8Claims
0Family size

Assignee

Inventor

Key dates

Filing dateOct 2, 1978
Grant dateApr 8, 1980
Priority date
Expiry dateOct 2, 1998

Classification

  • Technology area (CPC H)Electricity
  • CPC primaryH04M19/005
  • WIPO fieldTelecommunications
  • WIPO sectorElectrical engineering

Abstract

Telephone loop feed apparatus in which a hybrid couples audio signals to and from the subscriber loop and presents a high impedance to the loop relative to the loop impedance. DC power is coupled to the loop by matched resistors which determine the loop feed matching resistance. DC power is blocked from the hybrid to avoid saturation.

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