The first digital radio sets costing less than �100 went on sale in London on Wednesday - but were expected to sell out immediately.

They will become more widely available in August, and it is hoped that the "kitchen radio" will provide a breakthrough for digital radio stations.

BBC digital stations

Radios 1-4 and Five Live Five Live Sports Extra 6 Music: New and classic sounds 1Xtra: Black music, launching 16 August "Network Z": Comedy and drama, launching soon Asian Network: launching nationally soon

Broadcasters have been struggling to attract listeners, with sets costing at least �250 until now.

More than 50,000 of the new �99 Pure Evoke-1 sets are expected to be sold by Christmas - which would double the number of people listening to digital radio.

The new technology promises improved reception, easier tuning, more stations and extra features including text and pictures with some receivers.

BBC digital station 1Xtra is about to launch with DJ Semtex

The first available VideoLogic sets were expected to sell out after going on sale at two Dixons stores on Oxford Street.

There are hundreds of commercial and BBC digital stations available, according to Dixons managing director Chris Langley.

"Although quality content is available, the price of previous digital radios has been prohibitive for many listeners. This price breakthrough will bring digital radio to a wider audience," he said.

Commercial stations

Virgin, Classic FM and Talksport PrimeTime: Easy listening Core: chart pop Planet Rock: "Uncompromising classics" Life: Soft pop Oneword: Speech Bloomberg: Financial news Plus a range of local stations

The BBC has been transmitting its services digitally for seven years, and the first commercial digital services went on air three years ago.

A number of digital-only stations have been launched recently by the BBC, including 6 Music and Five Live Sports Extra, with new urban music station 1Xtra set to go on air on 16 August.

Digital radio is currently available to 80% of the UK population, and its backers say that figure will increase to 85% by the end of the year.

Only 55% of households would buy a �99 box to upgrade their TV sets for digital broadcasts, a new survey says.

Continental Research, which carried out the survey, said set-top boxes would need to be given away to ensure 95% of the population could get digital TV.

A BBC-led consortium recently won the licence to provide digital terrestrial TV, and it is hoping to push take-up of its free service with set-stop boxes costing �99.