What Cellphone








I read somewhere that it is possible for mobile phone users in the UK to use their phones in the United States. However, I would like to know if it works the other way around. In September a US colleague is coming to work in our office for three months.  I have been given the job of renting him a car, with a phone, unless thereís some way of getting his own mobile phone to work, when heís here?

C.R. Loxley, Westminster


British cellular phones -- analogue and digital -- do not work on US networks, which use the AMPS system. The opposite is true, and AMPS phones will not work here. What youíve probably seen is the services being offered by Cellnet and Vodaphone, whereby visitors to the US hire a phone when they get there, calls to their UK cellphone number are routed through to the US number. As far as weíre aware there are no reciprocal agreements with US mobile phone networks, for visitors to the UK.



Do you know of any mobile phone car kits for a Motorola 7500, that can be connected to a vehicle alarm? I occasionally forget to take the phone with me, when I park the car and Iím worried about it being stolen.

Stuart Duncan, Southend


Some car kits have such a facility, but even if it were obvious the phone was connected to an alarm, it would be unlikely to discourage the average car-thief. Leaving a mobile phone in your car, in full view, is simply asking for trouble!



Much has been written about the potential dangers of the high-frequency radiation emitted by mobile phones, but what happens when theyíre used in a car? I imagine that the radio waves must bounce off the metal roof, doors and floor, in much the same way as a microwave oven. Are we cooking ourselves every time we us the phone, or it no more than a light grilling?

Philip Culver, Barnsley, Yorkshire.


Hopefully neither. Microwave emissions from mobile phones are at a very low level and the energy contained in the signal follows the inverse square law. That means that any heating effect -- and itís only barely detectable with the most sensitive instruments -- tails off rapidly more than a couple of centimetres from the antenna. In any case, car kits with connections for an external aerial, channel the RF energy out of the vehicle and into the antenna.



I recently upgraded from a Motorola Micro TAC analogue mobile phone to a new 7500 GSM digital model.  I chose this one -- even though it was being discontinued -- because it fitted my existing car kit. I have to say that Iím far from impressed by the quality of the digital networks (I subscribe to Cellnet). I have found that the coverage is not as good as my old analogue phone, calls drop out more frequently, and I get a lot of strange noises. Should I have stayed with my faithful old Micro TAC?  

Lee Denton, Wrexham


Digital coverage in your area can be a bit patchy, but itís more likely that  fundamental differences in the way the two systems work is causing the problem. Itís often possible to hold a conversation with a weak analogue signal, it might be noisy, but you can still make yourself heard, even if it means shouting. Digital equipment is not so tolerant. When the signal is poor or intermittent the line will be dropped; marginal signals often produce so-called Ďartefactsí that make you sound like a Dalek. On the other hand, in areas of good coverage digital phones work very well indeed, moreover most networks offer a number of additional facilities, and data services, that are not possible on the analogue system. The analogue networks are due to be phased out in the next few years, maybe you should re-connect if digital coverage -- or rather the lack of it -- is causing a problem. Before you do, though, have your car kit checked out, and may consider a better antenna, especially if youíre using a Ďlossyí glass-mount type.



The kids have persuaded the wife and me to spend a week at Euro Disney in the Summer. Weíre going by ferry and will be driving to Paris. Iím self-employed and cannot afford to be out of touch so I need to know if my mobile phone will work on the journey, and when we get there? At what point will I have to change over to a French network? My phone is a Nokia 2110 and Iím connected to Cellnet Digital.


You may find coverage is a bit flaky mid-Channel. The phone should automatically register with France Telecom as soon as it looses the Cellnet signal. If not swich it off, then back on again once youíre in France. You should experience no problems along the Autoroutes and in the park itself. Before you go remember to check with your service provider that thereís no bar on international calls, read up on the instructions for making outgoing calls and donít forget the mains charger and a spare battery. Have fun!



I really canít agree with the fuss concerning using a mobile phone in a car. I admit itís probably not a good idea around town, but itís perfectly safe on motorways, when you donít need two hands on the wheel all the time, and certainly nor more dangerous than changing stations or loading a tape in the stereo. How can they ban it? What about taxis with radios, not to mention organisations like the AA and RAC who also use two-way radios with hand-held microphones?

Geoffrey Higgins, Lamberhurst, Kent


If the Government goes ahead and makes car-phones illegal, how will the police be able to tell when someone is using a hands-free model? Are they going to pull over anyone seen talking to themselves, or any car fitted with a radio aerial? I donít think so, itís about time someone thought this daft law through properly.

M.S. Seeney, Norwich, Norfolk


I speak both as a mobile phone owner, and as someone who has been involved in a accident with a driver using a mobile phone. Any new laws designed to curb the use of mobile phone use need to drafted very carefully, and not to outlaw the use of hands-free systems. They are no more dangerous to use than any other piece of equipment in a car, though I would make two suggestions, to improve safety even further. Firstly all car-phones should have a radio mute facility by law, so the car stereo is switched off as soon as the phone rings, and secondly, it should not be possible to dial out, whilst the car is moving.

Jill Parsons, Brighton, E. Sussex


As yet using a mobile phone in a moving car does not constitute an offence, unless it can be shown that it reduces the driverís ability to control their vehicle. There is growing pressure on the Government to introduce legislation, this is an important issue, your views and suggestions are very welcome and we fully intend to contribute to the debate thatís likely to ensue in the coming months.



R. Maybury 1997 1206




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