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Rkolsen2,752 posts since 20 Jan 2014
BBC World

The CEA-708 digital standard isn’t as flexible when it comes to recording. If your using a DVR it’s fine but if your outputting your receiver to a VCR (even ones with digital tuners) or a DVD recorder your out of luck. You would have to have your receiver output the captions to the recording device and they’d be burnt in with no way to turn them off.


Ah - I thought there were STBs that did 708 to 608 conversion at one point to allow for TV rather than STB decoding ? These would only work on SD outputs (same issue with DVB teletext, which can be re-inserted into an SD VBI for analogue SD output and display decoding, but has to be receiver decoded and burned into video for HD HDMI outputs)

Nope. The only way for a TV to do the decoding is for it to directly receive the signal.

Analog connections SD (composite) or HD (component) don’t transmit it either. So your stuck with the converter or STB.
Don’t let anyone treat you like you’re a VO/SOT when you’re a PKG.
Riaz614 posts since 6 Jan 2016
A long time ago I read an article about a proposal to integrate an MSX computer into a TV to create the first generation of smart TVs. This would not have been a difficult concept because many manufacturers of MSX computers also made TVs. An integrated MSX computer could be used in exactly the same way as an external MSX computer but it also provided a facility for software to be distributed via broadcasters by inserting it into the VBI. The possibilities would have been almost endless. Software could have ranged from video games to useful apps connected with TV programmes.
noggin14,365 posts since 26 Jun 2001

The CEA-708 digital standard isn’t as flexible when it comes to recording. If your using a DVR it’s fine but if your outputting your receiver to a VCR (even ones with digital tuners) or a DVD recorder your out of luck. You would have to have your receiver output the captions to the recording device and they’d be burnt in with no way to turn them off.


Ah - I thought there were STBs that did 708 to 608 conversion at one point to allow for TV rather than STB decoding ? These would only work on SD outputs (same issue with DVB teletext, which can be re-inserted into an SD VBI for analogue SD output and display decoding, but has to be receiver decoded and burned into video for HD HDMI outputs)

Nope. The only way for a TV to do the decoding is for it to directly receive the signal.

Analog connections SD (composite) or HD (component) don’t transmit it either. So your stuck with the converter or STB.


Ah - not the case here. Because we have a DVB version of teletext that is data compatible with the old analogue SD VBI system it's very easy for SD STBs to received DVB World System Teletext packets and insert them into analogue video blanking for TVs downstream to decode. It's very useful for analogue SD ring mains in hotels showing satellite channels (as the teletext services - including subtitles - survive Smile )
DVB Cornwall8,314 posts since 4 Dec 2003
Westcountry Spotlight
I remember the rather crude use of Teletext to switch the source feeds on OnDigital and ITVDigital between providers for whom there was insufficient space for a 24 hour stream. The pages were viewer accessible too. It did make it onto the DTT platform despite many discussions to the contrary.
Spectrum27010 posts since 12 Feb 2018
The US never adopted teletext on any significant scale but they had the V chip activated using data on line 21 of the VBI.


No - though a number of US stations ran services in the early 80s. Most used the 525/60 version of WST (i.e. the same system used in the UK modified for NTSC) - and I think TBS in particular ran a service. Zenith made TVs that had decoders, but when they re-engineered to add stereo functionality to their range, the teletext functionality was dropped, as by then it was clear it was going nowhere.

Some other stations in North America used a different system - NABTS (North American Broadcast Text Service) - which I think was originated in Canada and may have been linked to the French Antiope service a bit (France had their own bespoke teletext standard for a number of years before switching to WST).

Subtitles (aka Closed Captions) in North America are delivered using a separate system (much cruder, but also more robust, so it survived VHS recording) and the V-Chip system was integrated into this standard AIUI.

Yes, the service (W)TBS had was called Electra. They pretty much had nothing to do with it though. The service was in fact created by Taft Broadcasting in Cincinnati and broadcast by their flagship station, WKRC-12. It wasn't until 1985 that Electra went national. This was achieved by Satellite Syndicated Systems/Tempo Enterprises, the people in charge of uplinking WTBS to cable companies, putting it in on their end (ergo people in the Atlanta area who got WTBS over the air couldn't use Electra). Tempo also carried Electra and its' sister TEMPO Text (which from what I gather was mainly used for stock quotes and possibly sports stuff) on its' own Tempo Television network, which was mostly aimed at C-band dish owners and ended in 1989 when NBC bought the transponder to launch CNBC.

Aside from that, there were also a duo of services offered via the Discovery Channel: "Infotext", which carried agricultural related info as well as news and sports, and "Datavizion", which was family-oriented and was essentially the Fun & Games section of Ceefax combined with weird news stories and a satellite TV guide.

I've only ever found one or two pics of Electra and none at all of the other services. I have no idea if it's possible to extract pages from tapes of these channels as the Zenith-created teletext decoders (which were only compatible with Zenith TVs) seem to have vanished into the mists of time and Zenith TVs with the decoders built in are rather rare now.
noggin14,365 posts since 26 Jun 2001

I've only ever found one or two pics of Electra and none at all of the other services. I have no idea if it's possible to extract pages from tapes of these channels as the Zenith-created teletext decoders (which were only compatible with Zenith TVs) seem to have vanished into the mists of time and Zenith TVs with the decoders built in are rather rare now.


If recordings survive it should be possible. The current VHS archaeology uses video cards with VBI capture for software decoding, not teletext decoders, and lots of clever processing and error comparison. The US version of WST is a modified version of the European one (with a lower data rate because of the reduce vision bandwidth of 6MHz System M transmission) so could be do-able. However the lack of source material is probably the barrier to anyone bothering to do this.
Technologist43 posts since 10 Oct 2018
London London
Was teletext ever used anywhere on a significant scale for educational or entertainment purposes?

In Singapore there was a use of full field teletext to send back pages of information over the air as the return path if a Prestel like system. You had your own page address for “your” page
A sort if very early internet/ google like system
The Other use of full field teletext in City dealing rooms with lots if pages of financial data eg share prices etc.
Also it was the major use of the full address space to 7 FF 3F7F (mag 8 is actually mag zero )
And I did send compressed video,as full field text ....
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noggin gave kudos