Wish you could listen to your MP3 player while driving? Plans are afoot to overturn a law which currently bans mini devices that broadcast to your car stereo. But do they work?
Look, no wires to cause clutter
The iTrip is the best-known of the many wireless transmitters that allow drivers with MP3 players to play their music collection through any FM radio. At a stroke, such devices open up the insular world of the headphone-wearing MP3 owner.
There's only one problem - the low-power transmitters are illegal under the Wireless Telegraphy Act of 1949, which forbids the use of radio transmission equipment without a licence or an exemption. But Ofcom - the communications regulator - is considering legalising the gadgets, paving the way for them to be as popular here as they are in the US.
But there's a difficulty. As these gadgets have to be tuned to an FM frequency, using one in the congested airwaves of a major city disrupts the user's listening pleasure.
Chris Price, publisher to Techdigest.tv, used to have an iTrip to listen to his iPod while driving. But for a year it has languished unused - he grew fed up with local and pirate radio stations cutting in as he drove around London.
"It's completely useless in London as there are so many FM frequencies in use. I kept having to retune the thing each time to find a free FM frequency. Sometimes I'd get snippets of a station, sometimes it just took over. Obviously this is less of an issue if you live in the back of beyond."
While the devices' broadcast range is short - rule changes are likely to allow much weaker devices than in the US, transmitting less than five metres - in theory these could disrupt other users.
"If I stopped at the lights next to someone with their iTrip using the same frequency, I could overhear the other driver's music or simply static. But it's not that likely - it would have to be the exact same frequency, and there are about 100 to choose from," says Mr Price.
And by the same token, they can disrupt ordinary radio broadcasts. Many users tune into low or high FM frequencies, well away from major radio stations. But these ends of the dial are commonly used by public radio, given over to talk and news programming.
Matt Hollerbach is a keen community radio listener who lives on a busy road in Ann Arbor, Michigan.
"If I've got my radio at the front of the house by the road, you will hear a little snippet of a song and then the car is gone. It is a college town so a lot of it is hip hop. I'm not a fan."
He has been in touch with Don Foster, the Liberal Democrat culture and media spokesman, who is a strong supporter of reforming the current law. Mr Foster has assured him that community radio fans will not face similar problems here as the gadgets' transmission range will be so short.
Mr Price is more concerned that UK gadget fans will be sold a swizz. "It's ridiculous that these are unlawful, but there's an issue with people thinking they'll be able to use them without interference."
Add your comments on this story, using the form below.
Here's my tip for the congested London FM frequencies though: Unscrew the aerial on your car (if you can). It then won't pick up any other station except for the extremely local signal from your iTrip.
Geoff Marshall, Charleston, SC, USA
I've got one, it does work much better outside of London, and is perfect for motorway journeys. Even with the interference you get from pirate stations in London, it's still far preferable to listen to your own music.
I used to have one of these when I lived in Spain - not only could I not drive 100m without a radio channel butting in, but also I had to have the iPod in a certain place in my car for it to work. Move it and the signal was gone. I stuck to a much more lo-tech solution after that - a tape adaptor for the car. Sounds almost as good and runs all day without having to faff around. And have you seen how cheap in-car cassette players are now?
I mostly use mine to play music at parties; to connect an iPod to someone's stereo you normally have to fiddle with different connecting cables, and probably find you don't have the right one. The beauty of FM devices is that they make your iPod compatible with any stereo. And when you're not moving around, there simply isn't a problem with having to switch frequencies.
Steve Harris, Jersey
Simple answer, get a car with a tape deck. I have had varying degrees of CD player, MP3 players over the years and have successfully listened to what I want by using an adapter that you stick in the tape deck and connect to your headphone socket. Sometimes not keeping up with technology lets you get ahead of the game.
I bought one in Australia when I drove around the country in a campervan last year and after an hour it was essential. In the outback and much of the countryside there's no radio and my 7 CDs got repetitive pretty quickly. Being able to pump the entire contents of my iPod through the van's stereo system was invaluable when driving for eight hours straight several days in a row.
Billy, London, UK
I've been using an iTrip for years and wouldn't be without it. It makes driving and listening to music a lot, lot safer as on long journeys I don't have to take my eyes off the road to change CDs. And it's so much better than listening to the radio - I may not know what the iPod will play next but I know that I'm going to like it.
Eric, Bath, England
The design of your car has a lot to do with it. I have... urm... a friend who illegally uses one in both their cars. One car has its aerial on the roof of the car, above the front windscreen, and the reception is perfect. However, on the other car, the radio aerial is at the back of the car and the reception is often full of background hiss.
Martin Randall, Wakefield, UK
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