The station will host Test Match Special

But it is available only through Sky TV services or to those with new digital radios.

Most digital radios currently on the market sell for about �300 - although the first sub-�100 digital radios went on sale at the end of 2001.

The channel will not broadcast full-time, but will accompany existing medium wave news and sport station Five Live by giving extra coverage of football, rugby, cricket, tennis and Formula One.

It was one of the conditions laid down by the Department for Culture, Media and Sport that the new service be used solely as an overflow station for sporting events that could not be accomodated on Five Live and Radio 4 Long Wave.

'Top quality'

Launching Five Live Sports Extra has been an aim at Five Live for "many years", according to Bob Shennan, controller of BBC Radio Five Live and Five Live Sports Extra.

"We will be offering even more top quality sport to those who want it, broadcast with the same Five Live authority and informal style listeners have come to love," he said.

Digital radio sets will soon be on sale from �99

It will be joined by four other BBC digital-only radio stations throughout spring and summer.

Network X will play contemporary black music to a young audience and break new, non-chart UK talent.

Network Y will use the huge BBC archives of concerts and music interviews to explore music from the 1970s to the 1990s.

Network Z is described as "fun, intelligent radio" and intends to provide spoken-word entertainment in a way which will encourage new listeners to speech radio.

The Asian Network will be a national version of the local BBC Asian network, currently available only in part of the North and Midlands, with a 50% speech content in both English and a range of Asian languages.

The BBC was a pioneer of digital radio broadcasting, broadcasting its existing networks on digital frequencies since 1995.

Football radio

There are currently 17 national digital radio stations, including seven existing BBC radio stations that include BBC Radio 4 long wave and the BBC World Service.

By the end of 2002 there will be nearly 310 national and local digital radio stations in the UK according to commercial operator Digital One.

A number of commercial digital-only stations have already launched, including several dedicated to football clubs including Chelsea and Aston Villa.

The BBC is also launching a range of new digital TV channels.

Arts and documentary channel BBC Four will launch on 4 March, while two children's services will go on air from 11 February.