Nostalgic Prelude
Back in the old days of home computers, I started off with a BBC Model
B, tape recorder, dot matrix printer, and portable TV. The next hardware
add-on I bought was the Acorn Teletext Adaptor. This was a large beige box
that plugged into the Beeb, the mains, and a TV aerial socket. It was
controlled by a series of little tuning wheels (that always seemed to drift
when you weren't looking) and the Advanced Teletext System software. Of
course, the BBC were also broadcasting a range of Telesoftware for
downloading. As well as games, teachers' notes for schools' programmes, and
weather satellite pictures, there were programming courses and extra
software to let your adaptor do other things. Eventually, I had a system
that would search through all the pages transmitted, looking for keywords
(e.g. Cricket, Acorn etc.) and storing the first ten pages the keyword
appeared on. Eventually, the day came to upgrade to an A3000, and despite
the death of the Telesoftware service, my main concern was to keep the
Teletext access. Consequently I bought a Ground Control Teletext Adaptor
with their software. In some ways this was better, in that it multi-tasked
and I could watch the Test Match scores updating in a small window while
doing something else. It wasn't possible to search for keywords or do
anything fancy except click on a keypad or number embedded in a page to
change the displayed pages: you couldn't even use the keys to control it.
Unfortunately Ground Control closed down some time ago, and I thought I was
stuck with their software. I was aware of other Teletext systems, and that
Paul Skirrow, of the strangely-named Octopus Systems, was selling updated
software, but the price put me off. Eventually I decided to treat myself to
a copy though, and haven't regretted it.
Ground Control
For those who haven't seen one, the Ground Control adaptor
is quite small (20 × 13 × 6cm) with no controls or displays
apart from a mains switch and power LED. Mine sits on the floor covered in
dust and hidden in the general rat's nest of wiring behind the desk. It has
given sterling service since purchased, and stays powered up whenever the
computer is on. I currently use it with a RISC PC, but have previously had
it working with an A5000 as well as the A3000, as it plugs into any podule
expansion card connector (or you can solder the three wires directly on to
another expansion card). A good TV signal is needed to connect to the
adaptor's co-ax socket, but as long as you get a decent TV picture you
should be OK (only don't bother with those little set-top aerials because
the signal will be too weak). I have a splitter to feed both the computer
and TV, and get good reception on both. As well as the socket to connect to
the computer, the adaptor has a DIN socket with composite video and audio
output, giving access to the television picture and sound being broadcast on
the selected channel. This can be connected to an RGB colour monitor, to a
video digitising card, or even grabbing moving video directly with the
Computer Concepts Eagle card. When Ground Control went out of business,
Octopus Software bought up all their remaining stock.
The TTX+ Software
On upgrading, you get a floppy in a slim wallet folder and
an excellent A5 spiral-bound manual. Installation over the Ground Control
software is remarkably simple, and it even uses the same tuning information,
avoiding the need to re-enter anything. The list of features is
considerable, ranging from simple improvements such as displaying flashing
text and allowing keyboard as well as mouse control, to a sophisticated
predictive page cacheing system. Some example pages are also provided, and
I've included one of them here as the copyright statement on the broadcast
service prevents me from including real pages.
An Example Page
Cacheing
Teletext systems transmit one page at a time, with as much as 25 seconds passing before the page you've asked for being broadcast. The Octopus software tries to avoid this problem by storing pages in a memory cache, ready for future use. A simple text file is used to tell it which pages to collect, and a scoring system adds other pages you regularly look at to the cache. If a page is not currently being transmitted (e.g. company news pages on a weekend) then the search is abandoned after a few minutes to avoid "hanging" the system. You can specify the size of the cache depending on your page list (I have set a WimpSlot of 1Mb, which can hold 797 pages, but it can run in as little as 350kb with a smaller cache), and if you manually select a page it will be retrieved from the cache when possible, or the adapter will grab it for you. Sub-pages are dealt with the same way, and the display stays on the one you select until you press a cursor key to move backwards and forwards through the list. All this happens in the background while you get on with other things (it's running while I'm typing this, with a barely perceptible delay when a page is saved to the cache). The predictive cacheing is really cunning: the system keeps a list of the pages you actually look at, and gives them a score to reflect how often you check them. It then grabs pages in that order, so the chances are that it will have picked your favourite pages in a fairly short time. These can be on any channel, as it hops around following the score list grabbing them at 3-6 pages per minute. If you give it a while to stock the cache, you won't need to wait long for the information you want: twenty minutes or so is a good length of time, although my full set of 500 pages takes two hours to complete (although that's because I collect the Channel Four Share pages on p532 onwards, with their 80 or so sub-pages). I also tend to "disturb" the system by asking for pages out of sequence, which slows the cacheing down a bit. There are some sample lists provided for you to play with, so getting the hang of the principle and defining your own is very straightforward.
Part of My Page List
Of course, it can get caught out from time to time, especially with news stories changing during the day. However, there is a double check, as a page is first pulled out of the cache and then grabbed direct to deal with this situation. You might get a few seconds of the wrong story before the real one is displayed, but the system works very well indeed. It is also possible to disable all the sophistication to get, for example, the cricket scores continually updated.
Keyword Searching
Now this is something that really makes teletext on a computer
very useful. You can set up another list to tell the software which groups
of pages to search for what keywords. If I want to see references to
Hampshire (the cricket team), then I want to look in the sports pages only,
so as to avoid references to Hampshire (the county).
A Keywords List
I've got page groups for Sport, TV, Radio, News, Weather, Shares, Cinema etc. and they are searched on receipt and stored in a separate window. Clicking on the reference brings up the page for you to read, and allows you to build up a personal "electronic newspaper". Some suggestions are provided to allow you to build up your own selection, and ensure that you never miss an episode of your favourite TV or radio programme, or a particular film coming to a local cinema.
What Else Can It Do?
Lots of other things:
Why Bother with Teletext?
In these days of modems and WWW access, it's easy to overlook
Teletext as a source of information, but there are no subscription or
on-line charges (assuming you already have a TV license), it is updated more
regularly that any other information service I've found, and has a wide
variety of general news and information. OK, it doesn't have any significant
computing content, but the news, sports, business, and shares information is
excellent. In fact, I've seen postings on the Motor Sports Forum on
CompuServe quoting Ceefax reports as their source! Just make sure that you
have a valid TV license to cover the reception (a colour license is needed
for viewing Teletext on a colour monitor regardless of whether you have a
colour TV). If, like me, you've stuck with old, rather primitive teletext
software, I'd strongly recommend upgrading to Teletext+, and if you've never
really thought of it as an asset to your Acorn, Octopus have a few complete
systems left at a very reasonable price.
Availability and Prices
The Teletext+ V7·03 software for an existing adaptor costs
£39, and is suitable for Ground Control, Morley, Computer Concepts,
Design IT, Irlam and Solidisk teletext units. A hard disc is not necessary
to run it. Upgrades from earlier versions of Teletext+ are available by
email, and you should contact Paul for further information. A complete kit
of adaptor with software costs £169 while
stocks last. The package includes: Ground Control adaptor with built-in
power supply, Teletext+ software, podule lead with blanking plate (ie a
large podule plug to plug in to an expansion slot with the wire going
through a grommet set into a blanking plate). These prices all include UK
delivery and VAT, and the adaptors are supplied with a one year guarantee.
Full technical support is available by phone, fax, post or email, and I must
say that I've found Paul very responsive and helpful.
Octopus Systems have a WWW site with a page covering their Teletext software and hardware, and they can be contacted at
9 Randwell Close,Connectivity - Support - Education - Programming - Acorn Reviews - EPOC32 Reviews - Acorn Links - Psion S5 Links - Home
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