9 TELECOMMUNICATION TERMINALS FOR SPEECH, DATA, IMAGE, AND TEXT COMMUNICATION NAMELY TELEPHONE, TELEX AND TELEXTEXT UNITS, VISION PHONES, POS-TERMINALS, SCREEN-TEXT TERMINALS, FACSIMILES AND PARTS THEREFOR; TELECOMMUNICATION SYSTEMS FOR LANGUAGE, DATA, IMAGE AND TEXT COMMUNICATION, COMPRISED OF A MAIN STATION, AN EXTENSION STATION AND A SWITCHING APPARATUS FOR SIGNAL AND DATA COMMUNICATION TECHNOLOGY, DIGITAL/ISDN EXTENSION STATIONS, AND PARTS THEREFOR