Teletext

TV data and information

The Teletext service is made up of data and information read by European TV sets from the unused VBI (the Vertical Blanking Interval) lines of the PAL and SECAM broadcasts. The display can also be altered (made larger) so that reading this information is clearer. Teletext is primarily used in Europe but there are country differences in the service offered by TV companies around the world. The Teletext service is operated by MediaCorp News Pte Ltd and provides the latest updated news and information on demand. The service is available 24 hours a day.

Teletext consists of information, such as news and sports, which are viewed on a television set capable of viewing it, or via a set-top box attached to a standard TV set. Its roots lie in the 1970s, when the BBC and Oracle started the first test services. A new and improved version of Teletext was released in 1997. The actual Teletext data is broadcasted in a hidden part of the television signal, the VBI and decoded by the television (if it has a Teletext module fitted) or set-top box which then feeds the decoded signal to the standard television set.

As well as news and sports information, Teletext contains financial information, such as the latest stock prices, recipes, entertainment listings, advertisements, movie schedules and reviews, music and TV programme reviews, additional information on various TV programmes and more. Teletext also broadcasts subtitles (closed captions) for various programmes and news bulletins that are overlaid on top of the TV picture. The incorporation of Digital TVs by consumers will not end Teletext use but instead will enhance it. The MHEG-5 hypermedia standard has been picked as the standard authoring language for Teletext services using the digital terrestrial platform in the UK.

Do I need to pay to get Teletext?
No, Teletext is a free service transmitted to your Teletext-enabled TV set

How do I view Teletext?
You need a Teletext-capable television set to view the pages. Turn to the appropriate channel and press the TEXT button on your remote control. By default you will receive page 100, which is the main menu page. It gives you the page numbers where the various main categories are available on that channel. The pages can be accessed by using your remote control to key in a 3-digit page number.

Where can I find the content page?
Go to the Main Menu page 100. You will find the page numbers for the various main categories. There s usually a link to the main Index page.

Why does it take so long for the pages to be displayed?
In a conventional Teletext system, there is no way of relaying the page number you key in back to the broadcaster. Instead, all the pages are broadcast in rotation (known as a data carousel). Once you have keyed in a page number, your TV waits for the page to be broadcast and then displays it. Thus, the more pages a system has, the slower it will be. The speed of page access also depends on the size of your TV's memory chip. Some newer sets are capable of caching between 80 and 100 Teletext pages, allowing you to flip quickly through your most frequently viewed pages.

Why are some pages quicker to display than others?
The more popular pages are allocated more VBI lines to speed up access. As the number of VBI lines is limited, not all pages can be given the same amount of resources, and some will be slower to load than others.

Why do I get garbled text/jumping characters/missing words?
The problem could lie with your reception. If you are using a roof-top aerial, try fine-tuning the channel. In some cases, you may have to get a service engineer to adjust the antenna.

Why are there no fancy graphics or fonts and only a few colours?
This is due to the technical limitations of the conventional TV decoder. The Teletext screen has 23 lines of 39 characters on each line. For the purpose of graphics, each character is split into six pixels. Only eight colours are available.

Why do the numbers keep scrolling after I key in a page number?
The page does not exist or has been removed.

Why do some pages flip by themselves?
These are multi-pages that flip automatically after an average time of about 20 seconds. You can see which page you are on by looking at the top or bottom right-hand corner of the screen.  For example 2/5 is the second page out of five. To stop the page from flipping, press the STOP button on your Beo4 remote control. Press STOP again to release the page (you will need to do so for the page to be refreshed).

What is FastText?
FastText is a shortcut key that allows you quick, one-button access to a particular page. It works by downloading to your TV cache the other four pages linked to the page you are reading. Four coloured codes corresponding to four pre-selected pages appear at the bottom of the screen. Select the colour button on the keypad of your Beo4 remote control to access your preferred page.
FastText links work best if you have been on the page for about 30 seconds - the time needed to complete the downloading process. Viewers with older Teletext TV sets that do not have FastText are not able to use this feature.

Is the Teletext information on the Internet similar to that on TV?
The pages on the web may be delayed between 5 to 10 minutes because of the time taken to capture all the Teletext pages.

 

 

 

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