UK Digital Switchover

The main trasmitters will carry all 6 multiplexes on a much higher power than they are now, but the relays will not. They will only carry the multiplexes that are moved onto the frequencies of the analouge channels (that way they don't have to make changes to each relay). The 3 PSB multiplexes will definately be moved to analogue frequencies.

Though they will gain digital text - as you say a service replacement not a direct replica. (They gain in some areas - like better weather graphics, and lose in others, like flight information)



Yep - though the existing analogue services are now dog-free on terrestrial (unlike the early days when BBC One, BBC Two and Channel Four all had burned in DOGs on DTT and DSat... BBC One N Ireland was a particularly fave...)

This does'nt sound very fair, surely it would'nt be a massive effort to have all 6 mux's on the relays, eventually anyway. Is / will this be the case in other countries ? Also if we don't get HD versions of all main channels via DTT this will be another blow I think

The broadcast industry must reconsider, and with increasing urgency, plans to kill off "analogue" teletext services in view of the fact that almost all TVs in circulation can receive them - and more likely than not so can that brand new plasma someone will buy tomorrow!

The last year has seen improvements to the reception of Freeview text but there are still issues. Even on my 12-month old IDTV, I can still select a page and it will give up and return to P100 after a few minutes.

BBCi and Digital Teletext still lack the "homely" feel of their 30-year old predecessors - the pages remain clinical-looking, sort of like web pages being run on a system that isn't man enough. Which catches your eye more - P300 on digital Teletext, with the text restricted to one side of the screen, no double height main headline or heading banner, or the analogue version with all of these?

Recently I came across leaflets from 1998 showing how Teletext envisaged its digital service. It was far closer to traditional teletext, albeit with infinite colour palettes/fonts and the ability to insert photos. Maybe Teletext overestimated the technical capabilities required, but what we have almost ten years later is visibly inferior.

Indeed, they aren't actually losing a logo-free channel, they're gaining a lot more channels as a result of the changeover. They don't have to watch these channels, but even if they did that doesn't mean that they will mind the logo in the corner

Being 'homely' isn't really a good enough reason for stopping progress. Having a brand new TV system with a 1970's text system bolted onto the back of it would be an embarressment

Also remember that teletext doesn't work with digital TV in the same way as it does with analogue, it needs kit to encode the text, send it over the air and then software/hardware in the set top box to decode it and make it into traditional teletext. The millions of Freeview boxes out there that don't have the facility for teletext, it's too late to go back even if the industry wanted to

I find that I use less teletext (analogue or digital) now i've got broadband, I just don't need to use it any more and I'm sure I'm not the only one. I wonder if the days of digital text are numbered too

Err - it is a HUGE effort. You're talking about re-building over 1000 relay stations, adding a further three transposers or similar, and also possibly altering or replacing the transmitter aerials - as the 3 COM muxes are likely to be out-of-band compared to the 3 PSBs. Effectively, in many cases you'd be replacing and totally rebuilding the whole thing to ensure reception of non-PSB services. That is why they aren't doing it - at least initially.

There may also be an issue that the frequency plans won't support 6 separate muxes in the reduced TV band (once a large chunk has been sold off as the "digital dividend") at high power or relayed without interference...

I'm pretty sure it's been mentioned elsewhere but when the switch-off begins what will we see?

- A caption explaining what's happening?
- Snow?
- A caption on all regions from 2008 and then snow when the transmitters are switched off?

My understanding is that there'll be captions on screen prior to the closure in each area (although how they'll do this on a transmitter by transmitter basis in some areas I'm not sure).

BBC2 will be switched off first and replaced by a temporary MUX containing BBC1,2, ITV1, C4, five.

Then after a few weeks that, the remaining 3 or 4 analogue channels and any pre-exsisting DTT MUXs will will cease transmission and the new DTT MUXs will start

After the analogue services closedown you will see nothing (snow) as those transmitters will have ceased transmitting

Exactly, there are thousands of relay mast. By moving the multiplexes to the frequencies currently used for the analogue channels, the relays will automatically start rebroadcasting (as they just pick up whatever is on the channel it's programmed to and send it out again). They have done it in such a way that viewers don't loose the channels they currently get, and gain a few more too. Also, remember that almost all relays never had antennas for Five installed, so with the new setup many viewers will now be guaranteed reception of Five too. In the future it may be possible that some of the companies who own the relays start fitting aerials for the 3 COM multiplexes, expanding the coverage of them, but that isn't going to happen for the foreseeable future.

Almost. In fact BBC 2 will be replaced by PSB-1 (more or less what Mux 1 carries today)

As far as all the relays carrying all six muxes, forget it. One it's not economically viable for the COM mux operators, secondly not enough frequencies are available to do so. It's only technically possible at about 200 sites, the reality is only 81 will be '6 mux' equipped (one more than today, Fremont Point on Jersey)

Yes but it wouldn't be the freeview box that decodes the teletext it would be the TV.

With the majority of current boxes you still need both remotes to operate a large number of functions on the TV.

Plus I'd hardly call the mess that is MHEG "progress". It may be good for the interactive stuff but it's hopeless as a replacement for teletext.