Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
G08B—SIGNALLING OR CALLING SYSTEMS; ORDER TELEGRAPHS; ALARM SYSTEMS
G08B25/00—Alarm systems in which the location of the alarm condition is signalled to a central station, e.g. fire or police telegraphic systems
G08B25/01—Alarm systems in which the location of the alarm condition is signalled to a central station, e.g. fire or police telegraphic systems characterised by the transmission medium
G08B25/014—Alarm signalling to a central station with two-way communication, e.g. with signalling back
Schaltungsanordnung zur Kontrolle des richtigen Empfangs von Schaltkennzeichen in Fernmeldeanlagen, z.B. Fernsprechanlagen, insbesondere fuer Kennzeichenuebertragung ueber drahtlose Strecken