EP 0493973 B1 19970305 - Radio pager tone alarm circuit for generating variable duty constant audio frequency pulses modulated with unique tone pattern
Title (en)
Radio pager tone alarm circuit for generating variable duty constant audio frequency pulses modulated with unique tone pattern
Title (de)
Tonalarmschaltung für einen Personenrufempfänger zum Erzeugen von Impulsen einer konstanten Tastfrequenz mit variablem Tastverhältniss und moduliert mit einem eindeutigen Alarmtonsignal
Title (fr)
Circuit d'alarme sonore d'un recepteur d'appel pour la génération d'impulsions à frequence audible constante et à rapport cyclique variable et modulées par un unique signal d'avertissement
Publication
Application
Priority
JP 41850290 A 19901229
Abstract (en)
[origin: EP0493973A1] A POCSAG compatible pager where the output of comparator (17) is a square waveform of fixed pulse repetition frequency and increasing in steps mark/space ratio. The POCSAG alert tone modulates in an ON/OFF fashion the output of comparator (17) and this results in a sound level that escalates every 6 seconds. <IMAGE>
IPC 1-7
IPC 8 full level
G08B 3/10 (2006.01); H04Q 7/14 (2006.01); H04W 84/02 (2009.01); H04W 88/02 (2009.01)
CPC (source: EP)
G08B 3/1025 (2013.01)
Designated contracting state (EPC)
DE GB NL
DOCDB simple family (publication)
EP 0493973 A1 19920708; EP 0493973 B1 19970305; AU 649505 B2 19940526; AU 9010291 A 19920702; CA 2058536 A1 19920630; DE 69124974 D1 19970410; DE 69124974 T2 19970612; HK 1002413 A1 19980821; JP H04227134 A 19920817
DOCDB simple family (application)
EP 91312066 A 19911227; AU 9010291 A 19911230; CA 2058536 A 19911227; DE 69124974 T 19911227; HK 98101363 A 19980223; JP 41850290 A 19901229