As the national switchover to digital TV draws ever closer, a survey finds many families don’t understand about it or even know it is happening.

Four in ten UK viewers don't know about the digital switchover and only 7% know when it's happening in their area, according to the consumer group Which?

And that is an average figure. Only 6% of those in Wales and 7% of those the West Country know the date of switchover, despite the fact that normal analogue TV will be turned off in those areas as soon as 2009.

The current analogue broadcast signal will be switched off across the UK, region by region, between 2008 and 2012. Yet awareness of this is surprisingly low in all areas.

The forced conversion to digital television is also unpopular. 60% of viewers think it's wrong that there's no choice in the matter. And 9% even claim they'd rather give up television completely than be coerced to go digital.

Half the people surveyed didn't realise that to carry on watching TV as they do now, they'll need a Freeview box, Sky or cable for each television they possess. However, 17% said they wouldn't convert all of their TVs.

There are still 26 million sets that need modifying, according to Ofcom.

It's not just televisions that will need converting - other equipment, such as VCRs and aerials, might also need replacing or upgrading.

Which.co.uk editor Malcolm Coles said: "We've found that awareness of the digital switchover is alarmingly low, especially when you consider the first region is due to be switched over in just two years' time."

"People need information now so they can plan ahead. Digital UK needs to pull its finger out."

Which? said the official cost estimate of £132 per household to prepare for the switch-off was "conservative", especially for those needing a new aerial.