I’ve just been rewinding my radio. Yes, you read that correctly - rewinding my radio. I’ve been listening to a piece of music I missed the beginning of and so simply pressed a button and went back to the start. I can even record up to an hour of radio programmes on to a tiny memory card or listen to transmissions on my PC with a plug-in card.

The ability to rewind and record radio programmes is just one of the features being offered on a new generation of radios that use a system known as Digital Audio Broadcasting or DAB. DAB is more commonly known as Digital Radio. But be warned, not all digital radios can receive DAB broadcasts (the genuine article has a DAB logo).

DAB has been around for years (the BBC started transmitting DAB programmes almost a decade ago) but it’s only now that the service is beginning to take off.

The connection between DAB and computers is closer than you think. For starters, DAB uses computer technology to broadcast its signal. Instead of radio programmes being broadcast as constantly fluctuating radio waves, they’re sent as computer code - a vast number of ones and zeros. This has many benefits over the older analogue system used by FM and AM radio.

First, it’s more robust, so DAB transmissions are less likely to suffer from the pops, crackles, hiss and fade-out that can bedevil analogue broadcasts. Second, transmitting radio programmes as computer code means you can squeeze many more stations into the available frequency space. A large town or city can typically receive up to a dozen FM stations, but when it comes to DAB, the choice is closer to 35-40.

The BBC, for example, transmits its five main national stations on DAB, along with several stations exclusive to DAB, including BBC 6 Music, which draws on a 40-year archive of contemporary and classical music. BBC 7 covers drama, children’s programming, comedy and books. 1Xtra covers genres of black music. There are also many DAB commercial stations on the Digital One national network including One Word, which specialises in spoken word.

Added to this are hundreds of local DAB stations, many of which play specialist music.

And because the DAB signal uses computer code, text and graphics can be transmitted along with the audio, providing information such as the artist name and song title, an address or breaking news. That’s why many DAB radios have large LCDs. You can also receive DAB on your PC by using a plug-in DAB card and a free data service, called Digizone, that transmits multimedia content to PCs (such as news, text and graphics) along with audio.

DAB covers around 85 per cent of the population, so you need to check you can receive the service before buying any equipment.

DAB radios come in all shapes, sizes and prices, from pound;50 boom boxes to specialist tuners that leave little change out of pound;1,000. More and more products are dipping below the pound;100 mark and most can also receive FM broadcasts. One of my favourites is The Bug, from Pure Digital, a Wayne Hemingway-designed radio that turns many heads.

Another favourite is the Roberts Gemini 1, which comes from Roberts Radio, the company that specialises in retro-look products. It costs around pound;200 and has a new feature called PausePlus. The radio has an internal memory and as soon as you switch it on it starts storing or caching the last 15 minutes of the radio programme you’re listening to. Imagine you’re listening to a show and you miss a news item or didn’t quite catch an address; with PausePlus you just press a button and scroll back to the beginning.

The Gemini 1 can also record on to an SD (Secure Digital) memory card - a stamp-sized card that can store up to 1Gb of data. Roberts provides a more modestly sized card (32Mb) that’s big enough to store up to one hour of radio programmes. You can then replay the show on your radio or remove the card and play it on an audio player or PC that supports SD.

DAB has a lot of educational potential, but, sadly, there’s no specialist educational channel on the service - so far. However, the BBC says: “We provide a basic text service for BBC Schools on DAB. The schedule runs from 3am to 5am from Tuesday to Friday, and from 3am to 4.30am in the summer.”

Who would have thought the humble wireless would one day become such a close companion to the PC?

DAB websites

* BBC Schools broadcasts during the night on Radio 4. You’ll find a programme guide at www.bbc.co.ukschoolsguideradio_schedule.shtml

You’ll also find a FAQ guide to digital radio at www.bbc.co.ukdigitalradiol Digital One Operates a UK digital radio network, including One Word www.ukdigitalradio.coml Love My Radio Free online DAB magazine www.lovemyradio.com

* Digital Radio Development Bureau Answers lots of questions about digital audio in the UK www.drdb.orgl Digizone Multimedia radio service www.thedigizone.co.uk