TELETEXT
(First published in the AAPRA newsletter DIGIPEAT, October-December 1998)
Introduction
There’s a silent revolution happening on your BBS. It’s not
the reduction of WIA bashing bulletins, nor the elimination of the packet
pirates. It’s not even the reduction in volume of trashy WW bulletins.
Something far more important has come to pass, and it’s been so silent that you
may not have even heard about it. Alas, let me shatter that silence.
The Hunt
How often have you posed yourself a question and then
thought, I bet that information is on the packet network. Armed with that
thought you sit down in front of your packet screen and go logging in to your
BBS, ever hopeful that you can find the information you seek. Where do you
start? The BBS has what seems like fifty thousand messages. How do you go
through all of those? I could use the LC
? command to list all the categories of messages, and after looking through
over 300 of these you could then pick the categories to list and then read each
relevant message.
Another way would be to do a search through all the message
subjects with the LS command and
read through each message. There are other ways, but all-in-all it’s a bit of a
bear trying to track down the information.
The Catch
What is needed is a way of gathering all of the information
together and categorising it for easy access, perhaps with a hierarchical
system of menus to make it easier to navigate. Enter Teletext, a data storage
and retrieval system based on pages of information accessed by number. Teletext
originated in the TV broadcasting industry and has now been adapted for packet.
In TV, the unused bandwidth available between each field of the picture was
utilised for sending textual data and limited graphics. The data slipped
through unobtrusively and any viewer equipped with the appropriate Teletext
signal decoder was able to select pages via a keypad and view them on their TV.
Channel Seven runs a very good TeleText system.
Packet Teletext
Just like the TV scenario, there is TeleText data being shipped around the packet network quite unobtrusively. Unlike TV though, the information is being stored by each equipped BBS, mainly to allow fast retrieval. The data is unobtrusive because it is all sent as personal messages rather than as bulletins and this is done to guarantee delivery at each operating BBS. The same cannot be said for bulletins which can easily go astray for a variety of reasons.
Using TeleText
There is a good chance that your local F6FBB BBS is a
cooperative TeleText system member. If not then there is probably one not too
far away. Most BBSs advertise that they have the TeleText system in the command
prompt. They show the command TT, mention TeleText or sometimes it is called
Think Tank. Any system which does not show this probably is not running the
system. You can see for yourself by entering the TT command and watching the
response. An error message is not a good sign!
TeleText Commands
There are surprisingly few commands to learn - “what a
relief”! Entry to the system is gained by TT
and you can exit again with B to
quit completely or F to get back to the BBS. A help listing is obtained
by entering ?. The pages of
information themselves are displayed by entering a three digit number such as
100 for the index page. The available number space has been divided up into
ranges to cater for various related interest areas. Each of these has its own
index so that it is possible to see by downloading just a few pages what is
stored in a particular area.
Categorisation
The categorisation based on number ranges is as shown in the
following table. Note that this applies to the TeleText system running on
packet BBSs in Australia and New Zealand only. In fact we are pioneers in this
area; the essential piece of software for handling the updating of the TeleText
pages was written in Australia.
000 Help screen (same as ?
command)
001 - 099 Local BBS pages (not released into national grid)
100 - 110 Index screens
111 Test page for all to use
112 - 199 FBB BBS overview
200 - 299 Experimenter’s corner
300 - 399 NZART
400 - 499 Continuation of pages longer than 7.5k
500 - 599 VK Packet Services
600 - 699 Clubs in VK3, VK5, VK6, VK7, VK8 and VK9/0
700 - 799 Federal Interest
800 - 899 Divisional Interest
900 - 998 Clubs in VK1, VK2, and VK4 plus Special Interest Groups
As you can see, there are a wide variety of topics. The pages from 001 to 099 are reserved for use by your local sysop. All the rest of the pages are sent around what is referred to as the national grid.
Content
The type of material suitable for inclusion in the TeleText
system is that which is of a fixed or slowly changing nature with wide appeal
to either the whole amateur community or to a defined interest group. An
example would be information on a local club, or the DXCC countries list, or a
list of 6m beacons.
Unsuitable material would include the coming events for a
club or Keplerian elements for amateur satellites. This material is too
transient and is better placed as a bulletin on the packet system.
Organisation
The national grid for the TeleText pages was set up by
Graham VK4BB and he administers additions and corrections to the distribution
system. He also looks after new pages being added to the system and distributes
a page with updates that have been made recently (page 999). In NewZealand, Phillip
ZL2TZE fulfils this role.
Contributions
Anyone can contribute pages to the system. In the case of
pages for the national grid, this is done by submitting them to VK4BB or
ZL2TZE. They check them and send them on the national grid. They also update
any link pages and send these out as well. The recent updates page is also
added to as well and this is periodically distributed.
If you have information for local distribution, this should be
sent to the sysop of your local TeleText BBS. There are special character
sequences to be included in a TeleText file, but that is beyond the scope of
this article. Consult your sysop for details.
AAPRA does not as yet have a TeleText page, however once the
web page has settled down it will be prepared.
Please try the TeleText system on your local BBS - it’s the
fastest way to find information on packet... And let the revolution continue!
Cheers … Gerard