Patent · US Expired

Security terminal for use with two-way interactive cable system

US4361730A · kind A · utility

179Cited by
2References
86Claims
0Family size

Assignee

Inventors

Key dates

Filing dateAug 29, 1980
Grant dateNov 30, 1982
Priority date
Expiry dateAug 29, 2000

Classification

  • Technology area (CPC H)Electricity
  • CPC primaryH04M11/04
  • WIPO fieldTelecommunications
  • WIPO sectorElectrical engineering

Abstract

A security terminal for use with a two-way interactive cable system. The security terminal develops alarm and supervisory signals, and controls their transmission over the cable when polled by a central station. The terminal discriminates between four different types of alarm condition (burglary, fire, medical and general emergency), and transmits respective coded signals over the cable, or over a switched telephone network if cable transmission is not successful. To further insure that alarm signals are properly transmitted in the event of a cable outage, the terminal responds to a cable-sent test command from the central station by causing the dialer to dial the central station over the switched telephone network; in this way, the dialer mechanism can be tested periodically to insure that it will be operative if needed.

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