Top teletext - the differences from the teletext standard

In the current teletext system access to the pages can be rather complicated. In fact, in order to choose a teletext page, a number of three figures relatative to the page must be inputted on the remote control of the television set. During this operation typing errors can be made: for example, an undesired page may be selected, or perhaps the decoder is not able to carry out the search, inasmuch a number of four figures has been inputted. Moreover the teletext user cannot verify in advance if a known page is available or not in the cycle.

As long as the number of the pages was limited (inferior to 100), the users could learn by heart determined structures. It was also possible to search by heart the desired page, after a short period of practice.

If the user did not remember the number of a certain page containing the desired information, he could locate it through the "starting page" or " index page” (100) and the successive “sub-index” pages. But this procedure indirectly lengthened the waiting time, thus making it unattractive to the user. The problems grew when the teletext services were widened due to the use of other lines contained in the vertical blanking interval.

Moreover another problem arises when the user can receive multiple teletext programs that are organized completely differently each time. Every home is already able to receive several teletext programs.

Therefore, in order to make the teletext more attractive, it was necessary to simplify the access to the pages and to make the contents more transparent for the user, in such a way that the user felt more comfortable: in fact, only pages easy to memorize were requested, while many other interesting pages were seldom used, so as that the users exploited only a small part of the rich teletext system.

The editorial effort for improving the production of all the pages can only be fully appreciated by the user when all the pages are easily accessible. Starting from this observation, it’s necessary to structure the entire programme in a better way and to simplify the search of the pages. In Anglo-Saxon countries a procedure called FASTEXT has been developed, while the television broadcasters of the German an Italian speaking countries developed a procedure called “TOP” that makes the teletext transmitted from the television broadcasters more attractive, without complicating the editorial work.