Patent · US Expired

Emergency announcement system

US4086446A · kind A · utility

4Cited by
0References
7Claims
0Family size

Assignee

Inventor

Key dates

Filing dateFeb 11, 1977
Grant dateApr 25, 1978
Priority date
Expiry dateFeb 11, 1997

Classification

  • Technology area (CPC H)Electricity
  • CPC primaryH04M3/10
  • WIPO fieldTelecommunications
  • WIPO sectorElectrical engineering

Abstract

A system is disclosed for providing emergency announcements to telephone subscribers when a group of communication paths is out-of-service. More specifically, one operative communication path extending from a base location to a remote location is connected at the remote location to a plurality of out-of-service or dead communication paths also extending from the base location to the remote location. Emergency announcements are transmitted from the base to remote locations over the selected one good path and applied to the plurality of dead paths. Subscribers are then connected at the remote location to the so-called dead paths to hear emergency announcements.

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