DTT Challenge 

1 October 2004 tbs.pm/2046

An additional perspective on why analogue should end sooner, rather than later.

The ‘beginning of the beginning’ of digital terrestrial television (DTT) didn’t exactly go smoothly. Those that did adopt an ONdigital box can probably tell tales of pictures breaking up whenever a motorcyclist rode past, and that was if you could get a signal at all. The beginning didn’t end very well either, as ITV Digital hit the dust in spectacular fashion.

Digital terrestrial television

But after a very rocky start, it seems as if the platform is finally finding its feet, helped by the launch of Freeview and the huge advertising campaigns by the BBC for its digital portfolio.

That’s not to say there aren’t still challenges with the technology, although better set-top boxes – along with power increases at a number of transmitters – have improved the situation. Changes in transmission methods on some multiplexes have also helped.

Even so, only about 70% of the country can receive a signal, and many of those users will need a new aerial in order to pick it up.

These problems have an unfortunate potential side effect: prospective customers will see the difficulties and assume that digital television through an aerial will always suffer from them; that DTT is a flawed technology.

The fact is that this perception is erroneous – there is nothing intrinsically wrong with DTT as a technology. The trouble is in the implementation.

A parallel for DTT’s problems can be found in the world of analogue television. Channel 5, the UK’s fifth and last analogue television station, may have launched in a blaze of glory in 1997, but its signal was nothing to write home about. With lower power and awkward channel allocations making antenna choices difficult, in many areas the picture is downright awful. Unlike DTT though, we don’t blame the technology.

Five’s problem was that it was crowbarred into an already overcrowded spectrum. Its transmitters are low powered to ensure they don’t interfere with the signals from the other four analogue stations, and from those in Europe.

At present, DTT has exactly the same problem. Its signals share the same broadcast spectrum as its analogue counterparts, and have to coexist alongside them without causing interference.

With Channel 5, the weak transmission strength showed itself with fuzzier pictures, or with people living in a valley not being able to get a picture whilst a friend half a mile away, and up the hill a bit, got a perfect one.

With digital terrestrial, the problem is revealed by pictures breaking up – showing the dreaded green squares that most DTT viewers will have experienced at some point in their viewing – or by being susceptible to interruptions every time a motorbike rides by, or someone uses a light switch.

Of course the problem could easily be solved – but unfortunately the only way to solve the problems is to turn analogue off completely. Turning off analogue would mean that today’s analogue frequencies could then be used for DTT instead. Although this would require some reorganization of frequencies, the result would be that DTT would become just as available as analogue is now.

It would also mean that DTT transmitters could run at higher output levels, and with that power increase comes the solution to DTT’s problems. Higher power would mean that interference from taxis and light switches would cease (just as they don’t cause problems for analogue) and DTT should achieve something at least close to current UK analogue coverage.

To a DTT viewer it sounds like a wonderful dream. But here’s the catch: it is years away.

The government decided that it won’t start to turn off analogue transmissions until the majority of the population have digital. The current aim is around 2012, although some believe that even this is unlikely. And even then, the problem is still simply getting people to go digital.

For this quest, DTT is actually quite important. There are still a huge number of people in this country without multichannel television, and the majority of those aren’t willing pay more for their TV. Whilst Sky has been very successful in signing up a large number of subscribers, the potential market is finite, and is probably getting close to saturation.

So if you want to sell those people digital, the importance of a non-subscription digital TV service is clear. Indeed, it’s the market at which DTT is now being aimed. Whilst you can get a digital satellite option without an ongoing subscription, it’s not an option that is not currently marketed by Sky and, unsurprisingly, public knowledge of the option is rather low. While Sky is soon to launch a better free proposition, it is still unknown how well it will be promoted. And to most people, if you want digital but not pay-TV, Freeview is the way to go.

But hang on… isn’t that the platform that suffers from interference, which isn’t even available in 30% of the country? And isn’t that Mr Vicious Circle standing in the corner with a smirk on his face?

Unfortunately, the government’s solution has been to be to just stick its collective fingers in its ears and hope the problem will go away, which is exactly what terrestrial broadcast digital TV doesn’t need. Instead, DTT needs to be helped out of the circle it’s currently stuck in. Neither of its problems are particularly easy to solve, so the only real way out is by brute force. The government needs to start closing down analogue stations by station, replacing the analogue signals with vastly improved digital multiplexes.

Sadly it’s this pro-active attitude that the government was for a long time, keen to avoid, no doubt too fearful of doing anything that might be perceived in a negative way by the dreaded focus groups. It may bring bad publicity, but it would certainly get analogue turned off by 2012.

Thankfully, after much pressure from the broadcasters and the regulator, Ofcom, the government is finally making moves in the right direction, even if not quite as forcefully as one would like. A trial in Wales has already been announced, and politicians are at least now openly talking about analogue-turn off.

Ofcom is now in consultation on what are called ‘Digital Replacement Licences’ for ITV1, Channel 4 and Five. Current licences allow analogue broadcasting plus the ability to transmit on DTT. The new DRLs, however, would prioritise digital transmission and oblige broadcasters to cease analogue by the end of 2012 at the latest, meaning that switchover could start five years before that. The DRLs, which will be issued by the end of 2004, require broadcasters to implement DTT services from 1154 transmission sites, offering a similar coverage to today’s analogue transmissions.

Unfortunately, however, the idea of closing analogue early isn’t a part of their plans. So will DTT’s quality improve? It’s hard to say.

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