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IN-CAR COMMUNICATIONS SUPPLEMENT
INTRO
Cradles and hang-up cups are the quick,
simple and cheap way of getting a mobile phone into your car and on the road,
but it’s only the beginning. Now we look at ways of powering the phone, simple
car kits and full-blown hands-free installations
COPY
Now you’ve got your mobile phone safely
installed in a holder or cradle the next logical step is to power it from the
car’s electrical system. Of course you could just rely on the phone’s own
battery but you’ll need no reminding that operating times can be limited, even
with a high capacity battery. Furthermore, if you’re going to be away from home
or the office for any length of time, you will need some means of charging the
battery.
The solution is a car power cord, also known
as a talk and charge adaptor, it’s a simple and inexpensive widget that
connects between the car’s cigarette lighter and the phone. Inside the adaptor
-- a small module attached to the cigarette lighter plug -- there’s a regulator circuit that does two
important jobs. Firstly it reduces the voltage from the car battery to the six
volts supply needed by most phones, and secondly it controls the amount of
current drawn by the phone and its battery. Accurate voltage regulation is
critically important, the output from a car battery can be as low as 10 or 11
volts on a cold day, rising to 15 volts or more when it’s being charged. Moreover, when the car is started, high
voltage peaks or transients -- generated by the starter motor and ignition
system -- could find their way onto the supply cable and damage the delicate
micro circuits inside the phone, so they have to be suppressed. Not all power
cords have this facility so it’s usually a good idea not to connect the phone to
the cord until after the engine is running.
Current regulation is equally important. If
allowed to do so, a flat phone battery will draw a large current, that could
damage the cells inside, due to overheating, so the current has to be carefully
controlled. Some power cords incorporate sophisticated charging circuits that
work like a mains desktop charger. Initially the charge current is high, so the
battery charges quickly then, once the battery is fully charged, the current
reduces to a trickle charge, keeping the battery topped up. The cord will also
deal with variations in current consumption that occur when the phone is in the
standby condition, and in use.
POWER CORDS
There are basically two types of power cord.
Simple battery savers, which replace the phone’s own battery pack, , and the
more common talk-and-charge type adaptor. Battery savers do not charge the
battery so we consider them to be of limited use, in any case they’re becoming
increasingly rare these days.
Saver-chargers or talk and charge adaptors cost only a little more than
simple battery savers, so you might as well charge the battery when it’s being powered
by the car battery. The remaining talk and charge adaptors fall into one of two
sub-categories: trickle chargers, and more advanced types with fast-charging
facilities. Trickle chargers are kinder to your phone’s battery, but they’re
not much use if you need to charge the battery quickly. If you think your phone
is going to spend a lot of time connected to a car power cord it’s a good idea
to regularly discharge the battery, to prevent the build-up of a ‘memory’
effect, which can reduce the batteries capacity by as much as 50% in just a few
months. Here’s a small selection of car cords that we’ve tried and tested:
WHAT CELLPHONE RECOMMENDATIONS
Algon Charger Cable, £35
Advanced adaptor using a delta V charging
system (just like a desktop charger) for automatic fast and trickle-charge
operation. A two colour LED indicator (red and green) signals when fast
charging has finished and the unit reverts to trickle-charge mode. Pricey but well
presented and easy to use.
Make/model Algon
10.915
Typical price £35
System fast/trickle
Features 2-colour
(red/green) charge indicator, replaceable 2A fuse
Build quality *****
WC Rating 90%
Contact ALLGON
ANTENNAS, Unit 11, The Courtyard Whitwick Business Park, Stenson Road,
Coalville, Leicester LE67 3JP. Telephone (01530) 510013
Andrew Rapid Charger, £35
Not all cigarette lighter sockets are the
same but this one fits most types with its slide-action plug. A well-designed
fast charger that automatically reverts to trickle charge. Charge status is
shown by a two-colour LED indicator and there’s provision for both high and low
capacity batteries. Worth thinking about.
Make/model Andrew
Rapid Charger
Typical price £35
Charge system fast/trickle
Features 2-colour (orange/green) charge indicator,
custom-fit lighter plug
Build quality *****
WC Rating 90%
Contact ANDREW
Ltd, Ilex Building, Mulberry Business Park,
Fishponds Road, Wokingham RG11 2GY. Telephone
(01734) 776886
Ora Power Cord £20
Basic controlled current trickle-charger that
works on 12 or 24 volt supplies (useful for truckers). Just the job for topping
up the phone battery on a long run. A single colour LED confirms power is on.
An interchangeable tip for the plug is supplied, so it will fit most types of
cigarette lighter socket.
Make/model Ora
MOTCP5
Typical price £20
System trickle
Features 12-24
volt supply, red LED power-on indicator, 1.5A fuse, interchangeable plug tip
Build quality *****
WC Rating 90%
Contact ORA 28/29 Faraday Road, Aylesbury, Bucks HP19
3RY. Telephone (01296) 415445
Power Wave Plug-In Charger, £25
A sophisticated stepped-current pulse charger
that alternates between high and low current cycles for a more efficient
charge. Suitable for both 12 and 24 volt supplies, and rated to up to 60 volts.
Quick and effective.
Make/model Power
Wave Plug In Charger (Motorola)
Typical price £25
System stepped
current
Features green
LED power-on indicator, 2A fuse
Build quality ****
WC Rating 90%
Contact GRM
Ltd., GRM Building, Copse Road, Fleetwood, Lancashire FY7 6RP. Telephone
(01253) 773177
SIMPLE CAR KITS
So now the phone is safely secured, it has an
unlimited supply of power and the battery is being charged, what next? No ifs or buts, the only safe way to use a
mobile phone in a car, whilst you’re driving, is with a hands-free car kit.
Pick up the phone to make or take a call and you could be prosecuted for
driving without due care and attention, and it happens! If using the phone
contributes to an accident then at best you could end up with penalty points on
your licence, or loosing it altogether, at worst it could cost you or others
their lives. That happens too!
Okay, lecture over, you know it makes sense,
the only problem is they’re expensive to buy, difficult to fit, and you have to
have a degree in computer engineering to use one, right? Wrong on all counts.
As far as cost is concerned the cheapest ones start at less than £50. Difficult
to fit? That depends on whether you’re capable of finding your car’s cigarette
lighter socket and a figuring out a piece of double-sided sticky tape.
Difficult to use? On the contrary, the whole idea is to make it easier to use
the phone.
Even if we haven’t managed to convince you
with compelling safety and legal arguments there’s the prospect of improved
reception, better sound quality, fewer dropped calls, greater range, almost
indefinite operating time, added security and a free charge for your phone’s
battery thrown in for good measure. Then there’s the cost-saving. Yes, that’s
right, a hands-free car kit can actually save you money, by allowing you to use
your existing mobile handset, rather than having to invest in a dedicated
car-phone.
Hands-free kits come in wide range of styles,
we’ll begin with the simplest ones, the sort that you can easily fit yourself
in a couple of minutes. At this point the range of options begins to narrow
because unlike power cords, which are available for most makes and model of
mobile phone, most hands-free kits rely on the phone having the facility built
into its operating system, and not all do, especially older models.
As far as the very simplest ‘wired’ kits are
concerned you’re in luck if you’ve got one of the many variants or clones of
Motorola’s Micro TAC and ‘Flip’ phones (digital and analogue), Ericsson models
-- especially the ever popular 237 and 337s -- and the Nokia 2110. which are
very well served by the accessory companies. On other makes it’s patchy,
especially if the phone hasn’t been around long, or hasn’t sold well, in which
case accessory manufacturers may not have caught up. The best bet in those
cases is to see if the original manufacturer has something suitable in their
accessory range.
Simple hands-free kits usually consist of an
adaptor module with a wired microphone and earphone, that plugs into the phones
accessory socket. The adaptor module often has provision for a power cord as
well; your existing car cord -- assuming you have one -- may not fit, or the
outfit will come with one that’s been specially designed for the job. This
arrangement will allow you to carry on a conversation, without removing your hands
from the wheel, other than to dial, or answer the phone.
There are some disadvantages to this kind of set-up
to be aware of. Firstly with most of them the phone’s ringer can only be heard
through the earpiece, so it has to be left in all the time. Not all of them are
especially comfortable, something to bear in mind if you’re going on a long
journey. Secondly, only you will be able to use the phone, if a passenger wants
to use it you’ll have to swap the earphone -- not very hygienic -- or
disconnect the kit, and that’s not very convenient if you’re passing a call
between yourself and a passenger. The
plus points are that this kind of kit is quite cheap -- £50 or less in some
cases -- and there’s no problems with installation, no holes to be drilled, or cables
to be routed. There are a couple of
kits that dispense with the wired earphone in favour of a loudspeaker, and
we’ve included one in our roundup. They’re a little more expensive and clearly
a lot easier to use but the downside is the microphones tend to be a fair
distance from the user’s mouth, so you might have to speak up to make yourself
heard above the road noise, and thus far they’re only available for a very
limited number of phones.
We’ve also encountered a couple of kits that
have no connection to the phone or the vehicle, these so-called ‘universal’
kits fit any mobile handset. They quite cheap -- typically £70 to £100 -- and
the one’s we’ve seen are powered by internal batteries. The phone is held in a
simple cradle, sound from the phone’s earpiece is picked up by a microphone, on
an articulated arm, and fed to a small amplifier which drives a separate
speaker. So far so good, except this arrangement relies on the phone’s
microphone to pick up the users voice from some distance away. Most are simply
not up to it, they’re designed to pick up sound from just a few centimetres
away, so you end up shouting. Apart
from anything else they’re ugly looking things as well, our advice is to give
them a miss. Here’s some simple kits that have caught our eye recently.
WHAT CELLPHONE RECOMMENDATIONS
ALLGON HANDS FREE PORTABLE £120
Currently only available for Ericsson phones
(Nokia 2110 soon), this ingenious two-part design comprises a speaker module
with boom microphone, that attaches to the headrest on the drivers seat, using
an elasticated band. The interface module clips to the phone and is powered by
a car cord. Neat and effective, though a tad pricey.
Make/model ALLGON
11.103/3
Typical price £120
System/fit Ericsson
197/198, 237/337
Features plug-in
hand-free kit with integrated speaker/microphone module and separate car-cord
Build quality ****
WC Rating 85%
ORA TRAVEL TALK £80
Clever one-piece design that plugs into the
car cigarette lighter. It contains power/charger circuit, amplifier and
loudspeaker. The microphone module is wired into the cable that connects to the
phone’s accessory socket. Brilliantly simple but you do need to talk quite
loudly to be heard at the other end.
Make/model ORA
MTH F5 ‘Travel Talk’
Typical price £80
System/fit Motorola
phones including: Micro TAC MkII, Classic, Flip-Phone, Cuo, Pro, BT Pearl,
Ford, Blaupunkt 582, Pioneer 740, Bosch Cartel S/SC/SL
Features plug-in
hands-free car kit with integrated speaker/power supply unit and microphone
Build quality *****
WC Rating 90%
Contact ORA 28/29 Faraday Road, Aylesbury, Bucks HP19
3RY. Telephone (01296) 415445
ORA CTM5, £45
Yes, it’s them again, this time with a well
designed kit containing a phone holder, car cord and earphone/mike lead. No
drilling required, just stick the holder to the dashboard using double-sided
sticky tape, plug the car cord into the ciggy lighter and you’re in business.
All it takes is a couple of minutes, there’s nothing to go wrong, it works well
and its cheap!
Make/model ORA
CTM5
Typical price £45
System/fit Motorola
phones including: Micro TAC MkII, Classic, Flip-Phone, Cuo, Pro, BT Pearl,
Ford, Blaupunkt 582, Pioneer 740, Bosch Cartel S/SC/SL trickle
Features simple
hands-free car kit with phone holder, car cord and microphone/earphone
Build quality *****
WC Rating 75%
Contact ORA 28/29 Faraday Road, Aylesbury, Bucks HP19
3RY. Telephone (01296) 415445
FULL CAR KITS
Simple hands-free car kits are fine for the
occasional user, but for those who earn their living behind the wheel, and
depend on staying in contact then there’s no substitute for a proper car kit.
But what about dedicated car phones? They’re good too, but these days
differences in performance, convenience and features between purpose-designed
car phones and mobile handsets used in good quality hands-free car kits have
narrowed to the point where there’s almost nothing to choose between them. In some
ways mobile handsets are better, because you can take them with you when you
get out of the car.
Hands-free car kits for mobile phones have
been around for a while but they’ve only been to be a viable alternative --
economically at least -- to dedicated car phones in the past two or three
years. Initially they were only produced by the phone manufacturers or OEMs
(original equipment manufacturers); they were horrendously expensive and only
available through authorised dealers or specialised installation companies.
Everyone did very nicely out of this tightly controlled market, thank you very
much. Then a few more kits began to appear, made by accessory companies, though
at first they too were mainly marketed through installation companies who would
fit them for you, for a price of course. Then, about two and a half years ago,
the floodgates opened, and hands-free car kits found their way onto the open
market, freely available from everyone from high-street retailers, to market
stall holders and mail-order companies.
Full car kits differ from simple car kits in
three ways. First they’re permanently installed in the vehicle; secondly they
have the facility to connect an external antenna, and third, there’s the option
to boost the signal output to the same level as a proper car phone. Full car
kits also mark the dividing line between have-a-go DIY installations, and
letting the experts do it. With these outfits there’s no way of avoiding
drilling holes in your car, rooting around under carpets and trim, threading
cables through small holes and fiddling with the car’s electric’s. In short
there’s a whole bunch of opportunities to foul up, possibly with disastrous
consequences. Nevertheless, it’s fair to say that it’s not beyond the resources
of a typical handyperson, and anyone who has installed a car radio or alarm
shouldn’t have any problems doing it.
If you fancy having a go, it behoves us as a
responsible consumer-oriented magazine to draw your attention to a publication called ‘Code of Practice
for Installation of Mobile Radio Equipment in Land-based Vehicles’ or MPT 1362
to its friends, published by Department
of Trade and Industry. It has been written for professional installation
engineers, and it covers a wide variety
of mobile communications equipment, but it’s jam-packed with sensible advice
and guidance regarding the hazards involved with this kind of work. A while
back the DTI told us they were toying with the idea of putting together a more
digestible version for cellphone installers and DIYers but the last we heard
they were still thinking about it.
Most of what this sizeable tome contains is
common-sense. The golden rule is to plan the installation beforehand, well
before you reach for the electric drill. Lay out all the cables first, check
the length of runs, and make sure they’re not going to chafe against sharp
surfaces, or get in the way of any moving parts. The position of the phone is
very important -- this applies equally to all types of car kits -- and make
sure that whatever the holder is attached to can bear the extra weight or
strain. Its location should be within easy reach of the driver, and preferably
within their field of vision, though make sure it doesn’t interfere with any
controls or instruments.
Mobile phone antenna installation is probably
something most DIYers won’t have come across before, but again there’s no great
mystery to it. For the best results the aerial should be mounted as high up as
possible, with as much of the radiating element clear of the car’s roof-line as
possible. Make a note of where the
aerials have been fitted on cars of the same make as your own if you’re unsure
where to put it. There are lots of
different types of cellphone aerials on the market, and a wide variety of
mounting systems, but the most convenient (and cheapest) ones are 1/4-wave
glass-mount whips, which are suitable for 95% of all cars. They do not require
any drilling, and can be fitted (and removed) in a matter of minutes. The trick
with these antennas is to thoroughly clean the class beforehand, most outfits
contain cleaning swabs for this purpose. If the glass is dirty then the antenna
will drop off...
WHAT CELLPHONE RECOMMENDATIONS
ANDREW HANDS FREE KIT £230
This is one of the most complete kits on the
market, and eminently suitable for DIYers. The kit is very complete, it even includes
an antenna, which is normally supplied separately
with most other kits. The cradle/holder has the speaker built in, which further
simplifies installation.
Whilst the instructions have been written
principally for installers they’re clear and easy to follow. Operation is very
straightforward. The phone slots into the holder, the feature connector is
built into the cradle, so there’s no cables or plugs to worry about. Performance is generally good, though it
could do with being a bit louder and it might be a struggle to hear the caller
in a really noisy car.
Make/model ANDREW
SIMPLE CAR KIT
Typical price £230
System/fit Motorola
Micro TAC, Flip and family,
Features integrated
cradle and loudspeaker, kit includes microphone, antenna and all cables
Build quality ****
WC Rating 90%
Contact Andrew
Ltd., Ilex Building, Mulberry Business Park,
Fishponds Road, Wokingham RG11 2GY. Telephone
(01734) 776886
ONLINE HANDS FREE CAR KIT, £100
This kit is intended for DIY installation,
and that’s reflected in the simplified power connection -- it uses a cigarette
lighter plug -- and lower than average price. That’s also helped by the fact
that the kit doesn’t include an antenna, though it has the necessary
connections. The kit does, however, include a microphone, loudspeaker, mounting
bracket and a set of fixing screws. The phone connects to the unit via a
plug-in curly lead, so it can be picked up and used as normal. The controls are confined to a volume knob
and LED charge status indicator. Sound
quality is good at both ends of the connection, the speaker is not very loud
though. Good value.
Make/model ONLINE
HANDS-FREE CAR KIT
Typical price £100
System/fit Motorola
Micro TAC family and clones
Features simple
power connection, kit includes cradle, speaker microphone and cables but not
the antenna
Build quality *****
WC Rating 95%
Contact Online
Accessories, 1-15 Kingston Road. Freemantle,
Southampton SO15 3DB. Telephone (01703)
237111
ATEC HANDS-FREE
KIT £170
A smart-looking
kit all the way from Italy with an unusually small cradle. That’s because all
of the electronic gubbins are housed inside a separate box, that can be tucked
away under a seat or behind the dash. The extra cabling and box of tricks makes
it a little harder to install, and the instructions are a bit thin, but it
should still be within the capabilities of most handypersons.
Audio
performance is good, bags of volume and speech quality is fine, at both ends.
Worth
considering.
Make/model ATEC HANDS FREE KIT
Typical price £170
System/fit Motorola
Micro TAC family and clones
Features separate
control electric’s and power supply module, outfit includes cradle, mount,
speaker and microphone
Build quality ****
WC Rating 95%
Contact Lemon,
telephone (0500) 282104
BOOSTERS
All of the car kits we’ve looked at have no influence
on the power output of the phone they’re used with, though clearly an external
antenna will improve transmission and reception performance, particularly in
difficult conditions. However, hand-portable phones have a Class 4 output of
just a few milliwatts, which is well below the Class 2 output of a dedicated
car phone or transportable. A device called a signal booster can be fitted to
most car kits, that increases the output to Class 2. Signal boosters fit in
between the aerial and the cradle and are powered from the car battery. Because
they only handle radio-frequency signals, and operate independently of the phone
they’re not normally specific to a particular make or model of phone or car kit.
Unfortunately this is a rather touchy
subject. A good proportion of the cellphone boosters sold in this country are technically
illegal. These devices, known in the trade as linear amplifiers are classed as transmitters,
and as such require BABT approval before they can be sold for use in the UK. Accessory
companies we have spoken to have told us that the procedure for obtaining
approval takes forever. One firm commented that a phone could be obsolete
before the certificate is granted, so whilst many companies stock signal
boosters, they only sell them for ‘export’.
It’s a different situation when it comes to the
boosters sold by the phone manufacturers, for use with their own car kits. In
most cases they will have (at least we hope they do), BABT approval; phone manufacturers,
unlike accessory companies don’t have to concern themselves with the vagaries
of the market, and their products are less price sensitive. So there you have
it, signal boosters are available, but the ones we’ve looked from accessory
companies did not have BABT approval, so we can’t really recommend them to you.
By the way, watch out for products that
purport to ‘boost’ the signal from your mobile phone, most of them do nothing
of the sort, unless of course they are linear amplifiers. Most of them involve
some form of antenna trickery, and creative use of ‘gain’ figures, to suggest
you get something for nothing. In fact antenna gain is nothing more than a
trade-off, a stronger signal in one direction means a weaker signal in another.
Some of them may indeed yield small improvements -- every little helps with a
Class 4 output -- but there’s always a price to be paid, normally with
increased directionality or reduced sensitivity, resulting in less reliable
contacts when on the move. That’s the good news, the bad news is that many of
these snake-oil remedies have no effect at all, some even impair performance.
Just remember that there’s no such thing as a free lunch, not even in the
cellphone market.
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Ó R. Maybury 1996 0403
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