Method and apparatus for reporting dangerous conditions

摘要: Attorney's Docket 7337 CAN INVENTORS: ALAN PAUL TROUP et al INVENTION: METHOD AND APPARATUS FOR REPORTING DANGEROUS CONDITIONS ABSTRACT OF THE INVENTION In an alarm system a central signal station periodically transmits interrogation signals, preferably in the form of infrared radiation packets to remotely located detectors which transmit response back after differing time delays that are characteristic for individual and permit localization source signal. state, respond every signal, normal operational state only mth i.e. less often, diminishing battery potential small pth even often. The is determined from frequency with signals transmitted by detectors, ratio signals. WWK:FR:rmw:mncl