The system will offer listeners near compact-disc-quality sound, more robust interference-free reception, more channels and extra services such as text data.
Liz Forgan, managing director BBC network radio, said the occasion was a "historic moment" marking the "dawn of a third age of radio - the technological progression from AM, which is now 100 years old, and FM, now 50 years old, into the digital multi-media world of the 21st century. Consumers will get superb quality sound, a fade-free signal and a whole range of new services on simple, easy-to-use sets."
Yesterday's switch-on means that BBC Radios 1, 2, 3, 4 and 5-Live, which are transmitted via conventional analogue delivery on AM and FM, will also be available on the new digital system. The corporation also announced a further digital network that will broadcast sport, live coverage of Parliament and selected World Service programmes.
However, despite the acknowledged benefits of digital technology, the vast majority of listeners will be unable to share in this latest radio revolution for several years.
To receive the improved signals, consumers will have to invest in special equipment that is only at the prototype stage. As it becomes more freely available over the next two to three years, prices are expected to fall from current levels of between pounds 500 and pounds 700.
Ms Forgan accepted that providing listeners with an incentive to pay for the new receivers would be a challenge, but said the BBC had to move ahead of the market if it was to fulfil its public service obligations to drive radio forward into the next century. The corporation will spend pounds 10m putting the appropriate transmitters in place and an initial further pounds 50,000 on new programmes.
Electronics manufacturers would not be prepared to invest in the new technology unless somebody was already out there broadcasting. "There is logjam at the moment and it is the BBC's job to free it up ... measured risk-taking by the BBC will help prime this market."
The other factor militating against widespread listener uptake will be its availability across the country. The initial DAB service broadcast from five transmitters will be restricted to Greater London and the M25. By March 1998, a further 22 transmitters will come on line, broadening coverage to 60 per cent of the population. However, the remote mountainous areas of Wales and Scotland, which experience the most acute reception difficulties and would therefore benefit most from DAB, will not be served in the immediate future.
Glyn Jones, managing director of DAB, said the BBC would use the system's bedding-in period to experiment with the types of service it would like to provide. The technology also allows for the transmission of text, data and pictures to accompany the item.
A new "audio-on-demand" service unique to DAB called BBC NOW, Mr Jones added, would begin next year. This would be a 24-hour information channel based on a rolling 10-minute package of news and business headlines, sport, weather, traffic and other programme information. If developed fully, listeners will be able to select which type of information they are interested in receiving, rather than relying on the broadcaster's schedule.Reuse content