Television Text: First Experience with a New Medium

Abstract

New information services are becoming available for home users. These use the broadcast television channels—as in Teletext—and the public telephone network—as in Viewdata—to make information in the form of text and diagrams available on the screens of domestic television receivers. The viewer has a keyboard so that he or she can choose what to see and when to see it. Such services are expected to grow, and further sources of information will become available which use similar display facilities. The main features of these new systems are outlined and an experimental home terminal equipment that has been used to explore development in this field is described.

The displayed text pages are currently limited to a maximum of 960 alphanumeric characters or to simple diagrams. This represents a very small window with which to observe what may be a very large amount of information. Normal search and scanning techniques developed for books and newspapers do not necessarily apply. The paper outlines the methods currently used and their limitations, and describes possible further technological development which may be helpful. Other features of the display, such as the restricted paragraph size and the free availability of coloured text, are also commented upon. It is concluded that television text is an attractive medium that will play an important role in future communications.

In recent years a new technology in electronics, known as Very Large Scale Integration (VLSI) has been introduced. Using this technology, it becomes possible to manufacture complex circuits involving hundreds or even thousands of devices which occupy only a minute space and can be mass-produced cheaply. As a result, the electronic storage and processing of information is easier than ever before, and the cost of the circuits is within reach of the ordinary person. The electronic calculator is perhaps the best known example of this phenomenon. However, hard on the heels of the home calculator, we now have the home information system.