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Orry Verducci1,545 posts since 1 Feb 2005
Granada North West Today
Following on from the talk of the recovered Teletext pages on the TV Whirl topic, I thought I'd start a new one talking about the many recoveries that have been put online this past year, which as far as I can see seems to have gone unnoticed by TVF.

This past year a group of teletext enthusiast software developers and former teletext engineers have been working on software to recover teletext from Standard Play VHS tapes, by trying to interpret the lower resolution VBI in the same way barcode reading software scans images, and comparing the multiple copies of the page to guess where the errors are and correct them. Transdiffusion ran a story on it at the start of the year: https://www.transdiffusion.org/2016/01/07/teletext-time-travel

One of the developers has built up a large collection of recoveries he's made at: http://www.uniquecodeanddata.co.uk/teletext76/

There's also a collection from another of the developers at: http://al.robotfuzz.com/~al/teletext/

There's lots of the complete Ceefax, Oracle and Teletext from multiple dates over the years to be explored again.

For the really geeky among you, they've even developed software to get the Raspberry Pi to output teletext data on to the VBI on it's composite output, which you can find at https://github.com/peterkvt80/vbit2/wiki. It comes with a complete copy of ITV Teletext to explore on your TV just like the good old days, as well as their own Teletext service that they've been developing for fun.
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Inspector Sands10,634 posts since 25 Aug 2004
It's some sort of test page. Such pages usually have a letter in the page number so that they can't be typed on a remote. I'm surprised a regular page number was used as late as 1994.

Teletext had an interesting engineering page that showed the queues of pages being sent to each transmitter. That was on a numerical page number, can't remember which one though. I once had a sheet that they sent out explaining what it all meant,unfortunately now lost
Neil Jones3,480 posts since 23 Dec 2001
Central (West) Midlands Today
Not sure if it was a "feature" as such but a teletext capable TV I had it was possible to scroll up and down through the pages with a letter in the page number once you'd pressed a key that let you there - I only remember this because of the Bamboozle! game Smile IIRC it started you off at I think page 12A and I could scroll to page 12F, which was one of the "wrong" answer pages. Think it also used pages 13A to 13F and 14A to 14F as well which I was also able to scroll through once I'd been given access through the coloured buttons.
Markymark4,489 posts since 13 Dec 2004
Meridian (North) South Today
Not sure if it was a "feature" as such but a teletext capable TV I had it was possible to scroll up and down through the pages with a letter in the page number once you'd pressed a key that let you there - I only remember this because of the Bamboozle! game Smile IIRC it started you off at I think page 12A and I could scroll to page 12F, which was one of the "wrong" answer pages. Think it also used pages 13A to 13F and 14A to 14F as well which I was also able to scroll through once I'd been given access through the coloured buttons.


They were hexadecimal page numbers, my memory of the queue pages Insp Sands mentions were that they
were on 6AA or higher which I accessed by stepping the + button beyond 699 ? I'm sure deep inside the 1974 BBC/IBA/BREMA spec it said that the receiver should suppress such pages, but manufacturers often love to ignore specs.
Orry Verducci1,545 posts since 1 Feb 2005
Granada North West Today
The majority of the broadcasters in Europe still have teletext services, I know for certain RTE (Ireland), TVE (Spain), ARD/ZDF (Germany), NPO (Netherlands), SVT (Sweden) and Rai (Italy) still have full teletext services. Some of them even have Level 2 services which utilise more colours and better graphics (ARD and NPO). I've got a feeling France Télévisions may have closed theirs at switchover like us, but I'm not sure. They even have them on their HD channels through support on the receivers to access the text services directly from the DVB transport stream, bypassing the lack of VBI support on HD.

The Europeans never adopted digital text like we did, which basically secured the life of the old 'analogue' services on digital. I think we were the only ones to introduce digital text so early (arguably too early). It's only now with the introduction of HbbTV that the Europeans are looking into interactive digital services.

On the note of the test pages, or the engineering pages to more accurately describe them, they can be found all over the text services. They were all there as a way of the engineering teams to quickly check that the central server and the regional network were all in correct working order, and which parts had gone wrong if not.

Most (if not all) the regional ITV text services had a page on 6AA which show the status of the local teletext inserter and when it was last updated over the network, for example this is Granada's: http://al.robotfuzz.com/~al/teletext/itv/2000-05-05-0048.3/6AA.html

Teletext had theirs on 379 for most the 90's, for example this one from 1995 showing the network with a problem somewhere: http://al.robotfuzz.com/~al/teletext/itv/1995-11-04-0003.5/379.html. Looking at the recoveries it seems the page disappeared around April 1998, replaced with normal content.

DBI, the company who used the VBI lines for the 700 magazine on ITV to provide a data transmission service to betting shops and the like, also had one on 799: http://al.robotfuzz.com/~al/teletext/itv/1998-04-14-0036.10/799.html

They were hexadecimal page numbers, my memory of the queue pages Insp Sands mentions were that they
were on 6AA or higher which I accessed by stepping the + button beyond 699 ? I'm sure deep inside the 1974 BBC/IBA/BREMA spec it said that the receiver should suppress such pages, but manufacturers often love to ignore specs.

I'm not completely sure of the original spec, but I know the current ETSI spec states that page xFF (with x being the magazine number, eg 6FF) should be assumed to be a timing placeholder and ignored, as well as subpage 3F7F. By the ETSI spec 6AA is a valid page.
Steve in Pudsey7,968 posts since 4 Jan 2003
Yorkshire Look North (Yorkshire)
Some other C4 oddities, the PDC status page - presumably the red and green blocks show whether it is up or down in each macro-region, and the A or B in the corner is to identify main and reserve kit.

http://al.robotfuzz.com/~al/teletext/c4/1996-05-26-0021.5/3BB.html
http://al.robotfuzz.com/~al/teletext/c4/1999-01-10-0036.14/3BB.html
http://al.robotfuzz.com/~al/teletext/c4/1999-06-20-0013.2/3BB.html
Write that down in your copybook now.