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.)
H04M11/00—Telephonic communication systems specially adapted for combination with other electrical systems
H04M11/04—Telephonic communication systems specially adapted for combination with other electrical systems with alarm systems, e.g. fire, police or burglar alarm systems
Schaltungsanordnung fuer Fernsprechanlagen mit Waehlerbetrieb und mehreren Vermittlungsstellen, die durch induktiv abgeriegelte Leitungen miteinander verbunden sind