TELETEXT- a short technical description
This TV set displays Teletext information which includes stock market reports, TAB betting,
weather forecasts, and other useful material.
In Australia, the Teletext service is sent by the Seven Network, although other channels
send subtitles for the hearing impaired with programs marked by (S) in the TV guides. The
guides are not always correct! To get the full Austext service, the set must be tuned to the
Channel 7 Network. If there is no Channel 7 available, check with your local TV station.
The thing to remember about Teletext is that it is slow. It is the nature of the system
itself, where a large amount of information is sent using only a small fraction of the TV signal.
The Teletext picture is built up over many scans, and this makes the system slow and sensitive
to interference. If the TV signal strength is not good or shows interference on the screen, then
Teletext will drop an occasional word or letter. A better antenna is needed in this case, but
most of the time the results are excellent.
Teletext is controlled through the remote control unit. If you get yourself into trouble,
read the "Using Teletext for the First Time" hints and tips section later in the Manual. It may
have your answer.
Display
- The remote control has four buttons at the right hand side which control what will
be shown on the screen.
Button (15) puts the Teletext information on the screen.
Button (14) returns the TV display.
Button (17) mixes the two signals one on top of the other.
Button (13) switches to Audio/Video for VCRs and other equipment.
Pages
- The Teletext signal is sent in 800 pages, and when the Teletext button (15) is
pushed, the screen will be black with just two numbers - a black white "100" at the upper
left and an echoed black & red "100" at the bottom. This is the number of the main index
page, and it may take the system a few seconds to find it.
If nothing happens after a while, it probably means that the TV station is not sending
Teletext. Check that you are on Channel 7. Press button (14) to TV and switch channels.
(You cannot change channels from inside Teletext).
The required page is simply dialled up by pressing the numbers firmly on the "0 ~ 9"
keypad, one after the other. To call up page 186, press "1" then "8" then "6". The buttons
should be pressed deliberately, as it takes a moment for the push-button to register. The page
number is shown on the screen, together with the actual page being transmitted by the TV
channel, which counts up one page at a time. The pages are grouped in lots of
one hundred.
Speed
- It takes approximately 1. 5 seconds to send and display a page. In the worst case, if
the TV station is sending page 250 and page 24 0 is wanted, it will scan all the way up to 299
and back to 200 - and finally 240 before that page is shown on the screen. This would take
two minutes. In most cases it is half this.
Adjacent pages are held in memory, and may be displayed immediately using page
(- +) buttons (12), up and down.
Note: The + Button is also used to switch between single digit and double digit on TV.
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