Abstract: A system for transmitting an emergency call from a person requiring assistance. The system includes an emergency calling device coupled via a telephone exchange system to an emergency call receiving center having an operator. The calling device automatically dials a predetermined emergency telephone number upon actuation of a sensor by the person requiring assistance for placing a call to the emergency center. A first data device is provided for transmitting predetermined emergency data by frequency keying in the voice band to the emergency center. An intercommunication set in the calling device establishes a voice connection between the person requiring assistance and the emergency center operator. The intercommunication set is switchable between states of voice transmission and voice reception.

Abstract: A dialing device and method for using the device in a common dial network consisting of a central office and a plurality of user stations connected to the central office by subscriber telephone lines. At least one of the user stations is a calling station having a dialing device which incorporates a memory for storing calling number and identification number. The method comprises the steps of establishing a connection between the calling station and the central station via the subscriber terminal lines and via the central office, transmitting the new calling number of the central station and/or the new identification number of the calling station from the central station to the calling station and storing the numbers in the memory of the calling station.