Emergency call system

摘要

The invention relates to an emergency call system, the emergency call subscriber unit being connectable via subscriber lines of a dial- up switching network and via data lines and telephone connection lines to a central emergency call station. The subscriber lines of the emergency call subscriber station are used in this case in duplicate by providing, in addition to the AF speech path, a data transmission channel via which not only the emergency call telegram and acknowledgement and control signals are exchanged between the emergency call subscriber unit and the central station, but text communication between the subscriber and operating staff is also enabled. To match the communication capabilities of the respective persons seeking help, various input and output devices such as a keyboard, VDU or talk/listen device are provided in the subscriber unit. Advantageously, the telephone channel can thereby be kept free for telephone operation only.