Alarm system having bidirectional communication with secured area
US4918717A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Aug 23, 1988 |
| Grant date | Apr 17, 1990 |
| Priority date | — |
| Expiry date | Aug 23, 2008 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG08B25/016
- WIPO fieldControl
- WIPO sectorInstruments
Abstract
A security system which includes a master unit for communication with a central control station by telephone and provides for a plurality of remote detectors located in different zones of a secured area to be selectively wired. The remote detectors communicate through the main power supply with a master unit which is powered by the mains. Microphones in the remote detectors can be selectively operated through the master unit as activated by the central control station to listen in to different zones to permit for identification of a security breach in different zones. A high-volume output mode speaker phone is provided to the master unit. Feedback circuitry generates audible signals when the system is armed or disarmed remotely. Separate activation of interior and perimeter detectors can be effected.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.