Communication Methods : Teletext

The teletext system transmits text and very simple graphical information to televisions. To access teletext you need a television set with a teletext decoder built into it. Each television channel can provide its own teletext service. The channel supplies the information that is included on the service.

Teletext information is sent as pages, each of which is identified by a three-figure number such as 100 or 360. The pages are transmitted in sequence, one after the other. To access a particular page you must enter the page's number into your television using a remote control. You will then have to wait until the page that you want is next transmitted. When this occurs the page will be displayed, but you may have to wait for as long as a minute to view a particular page.

Typical information that is available on a teletext system includes news, weather, television listings, financial news and sports reports. Deaf people can use teletext to put subtitles at the bottom of the television screen so that they can read the words that are being spoken.

Advantages
  1. Most televisions can access teletext information. A television with teletext is only slightly more expensive than a television without teletext.
  2. Teletext is free to use.
Disadvantages
  1. The number of pages that you can look at is limited.
  2. Information can only be sent from the television channel to you. You can not interact with the system.

GCSE ICT Companion 04 - (C) P Meakin 2004