Cable Text and Cable Text Retrieval

Abstract

Videotext and Bildschirmtext, which are called Teletext and Viewdata in Great Britain, tend to become most promising new forms of text communication in existing networks. Their typical features are shown in Table 1. For some applications, however, the average waiting time of 12 sec or 5 – 6 sec, respectively, for the build-up of a text page on the screen is unsatisfactorily long. A considerable improvement in this respect may be achieved by using cable television or broadband distribution networks such as shown in Fig. 1. The great bandwidth of such a network (up to 30 channels) allows the realization of many new forms of telecommunication (Table 2) in addition to the TV programs. Table 3 lists the German expressions for the different possibilities of communicating text and still pictures which are displayed on the screen of a TV set.