The ITV digital fiasco looked to have dealt a fatal blow to the Government's hopes that we would all switch over to digital terrestrial broadcasts by 2010. But, as Nigel Burton reports, although digital may be down, it is by no means out.

IMAGINE the scene. You've finished your tea, consulted the paper and settled down to watch your favourite soap. You thumb the power button on the remote and the widescreen TV does... nothing.

You try switching on and off, fiddling with the set-up menus, even shouting and swearing. Nothing will persuade your expensive set to give up a picture as the time for EastEnders comes and goes. The screen remains resolutely blank.

Later on the reason for this televisual tragedy is revealed: the Government, in its infinite wisdom, has switched off the analogue signal received by more than 100 million TVs across the country. Anyone who doesn't have a digital set-top box can't see a thing.

The following day, you set off for your local electrical retailer with a pocketful of euros to buy digi-boxes for every television in your house.

It sounds pretty far-fetched and it's hard to believe any government would be so stupid but that's precisely the scenario Downing Street envisages sometime between 2006 and 2010.

When ITV Digital folded earlier this year it seemed as though the Government digital switch off had been scuppered. British broadcasting had never seen anything like it.

One day, 1.2 million customers were enjoying 40 channels, then, the next, all but a handful had been switched off. And customers are still waiting for an explanation. Nevertheless, it is wrong to think we should all give up on digital TV. As the number of bids for the digital broadcast licences given up by ITV Digital shows, there are still plenty of people who reckon they can make a go of it.

So what is going to happen? Should we all rush out and buy a television with a digital tuner or should we sit tight and wait to see what happens? In a bid to clarify some of the confusion, here's our straightforward guide to the state of digital play.

What is digital terrestrial?

If you want to watch digital TV programmes there are three options. Sky Digital which uses satellite technology to beam hundreds of new stations into your home via a dish; cable which transmits those programmes via a network of fibre optic cables; and terrestrial which transmits digital signals through the air.

In theory, terrestrial is the easiest way to join the digital revolution. Because the signal is received by a normal roof-top aerial, you should be able to plug your normal downlead into a set top box and receive whatever is out there.

Why would we want it?

Choice. Remember the fuss when Channel Four started broadcasting 20 years ago? Two decades ago, the concept of four channels was mind blowing. Today, Sky Digital offers more than 100 different channels catering for every taste from childrens' programmes to home shopping, movies to food and drink. If you want to watch first runs of Buffy, X-Files and Star Trek: Enterprise, then digital is the place to be.

Using a digital signal cleans up the picture, too. Analogue signals are susceptible to interference, leading to ghosting, colour shifts and wavy lines . Digital set-top boxes split a signal into red, green and blue components which, when used with the correct lead, result in brighter and sharper pictures. More programmes are broadcast in widescreen and stereo sound.

So why did ITV Digital fail?

It depends on who you ask. Critics reckon Granada and Carlton (ITV Digital's disgruntled parents) were wrong to try and take on Sky. They poured billions into a service that wasn't sufficiently diverse to offer something different. The decision to pay far too much for the rights to broadcast football league matches was the final nail in the coffin. So few people watched the matches it would have been cheaper to lay on a chauffeur driven limo and take each of them to the stadium personally.

ITV blames the Government. It says the signal wasn't strong enough. Thousands of would-be customers in the North-East couldn't receive a picture from their set top boxes even with a costly aerial upgrade.

ITV didn't help itself in this respect, however. It tried to cram too many channels into the limited bandwidth available. The result: pictures that frozen or broke up whenever the weather was iffy and boxes that crashed with monotonous regularity.

So what can we expect now?

The BBC's joint bid with satellite broadcaster BSkyB and transmitter company Crown Castle established a link between ITV and Channel 4 to win the three licences. The 12-year deal will see 24 digital free-to-view channels available via an existing aerial and set-top box costing about £100.

Which channels will I be able to receive?

The 24 channels will include the five terrestrial channels, plus S4C - the Welsh version of Channel 4 - and extra channels offered by ITV and the BBC. At the moment, this means BBC Choice, BBC4, the Beeb's Childrens' channel, and ITV 2. News junkies will be able to watch four rolling news and one continuous sport news channel spun off from Sky News and BBC News 24. The consortium is also planning channels dedicated to history, shopping, travel, and Parliament

Film fans will have access to one channel. This will most likely be the TCM service which transmits golden oldies and a handful of more recent movies.

When will this start?

Under the current plan, the service will go live this autumn.

Can I keep my ITV Digital box and still receive the new package?

Yes, but there is a catch. Of ITV Digital's 1.2 million subscribers, only 200,000 bought their boxes outright. The rest were given a box with their subscription and, technically, these remain part of ITV Digital's assets which could be sold off by administrators Deloitte and Touche.

So far the administrator has baulked at the cost of retrieving these boxes but, with each one worth around £100, the idea shouldn't be discounted altogether. If you're an ex-ITV Digital subscriber you'd best hang on to your box whether or not you intend to try the new service.

When will I be able to receive Sky's subscription channel via my aerial?

Under the current plan, never. The service will remain free for the duration of the licence, although you may be able to upgrade your equipment in a few years time to receive a limited subscription service.

Will the signal be any better?

The Beeb reckons so. It has taken a step in the right direction by cutting the number of channels from 36 to 24. Transmitters are also being upgraded. The signal is unlikely to reach everyone, however, leaving large parts of the North-East in the digital dark.

So why should I bother?

Good question. Looked at in the cold light of day, it's hard to see too many folk splashing out £100 to receive Sky News and re-runs of the Teletubbies. If the Government really is serious about switching off the analogue signal in a few years, it had better hope the BBC and its partners can come up with a few more compelling programmes.