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BOOT CAMP 217 (19/03/02)
TRAVEL TIPS, part 2
Portable gadgets like laptop PCs, pocket organisers, mobile
phones, camcorders and personal stereos have become essential travelling
companions – whether for business or pleasure -- but one thing the glossy ads
and brochures never seem to mention is that electronic devices that run on
batteries have a unquenchable thirst for electricity.
Virtually every portable PC and shiny pocket gizmo comes with
a mains adaptor/charger module, some of them half the size and weight of a house
brick, then there’s all the connecting cables, and if you’re travelling abroad
don’t forget the mains plug adaptors.
This week, in part two of our brief look at travelling with
technology we’re concentrating on the problems of portable power. And it is a
problem, and something you must consider whenever you buy a portable gadget. One
of the first questions you should ask is how long does it run on a set of
batteries or between charges? You should
then divide the answer by two and treat that as the absolute maximum you can
expect under perfect conditions, within the first three weeks of purchase…
The point is many manufacturers lie through their teeth when
it comes to battery running times. The highly optimistic figures they quote are
rarely, if ever, achievable in real life, where devices are used in a wide and
constantly changing range of temperatures. Usage patterns tend to be random and
unpredictable and the efficiency of re-chargeable batteries falls off rapidly
with use. If a product runs on disposable batteries be aware that claimed
running times are often based on the most expensive alkaline batteries. Don’t
forget that you will probably end up buying them as a ‘distress purchase’ at an
airport or gift shop, where you will almost certainly pay through the nose for
them!
That brings us to travel tip number one. Wherever possible shortlist gadgets that come
with, or can be powered by rechargeable batteries so take enough of them to see
you through the longest part of your journey (and remember to charge them before
you go…). Many devices are powered by proprietary battery packs so get a spare
but don’t just confine yourself to the manufacturer’s offerings, they’re almost
always the dearest and batteries from third-party manufacturers can be a lot
cheaper.
It’s worth spending a few minutes on the web, type the model
number of the battery you’re looking for into a search engine like Google (www.google.co.uk) and put ‘,uk’ (comma UK)
after the number, to limit your search to UK suppliers. For digital cameras,
camcorders, mobile phones etc., sites like http://www.strikalite.co.uk/home.asp
are well worth a visit. If there’s an option, go for one with a higher capacity
than the standard offering. Battery capacity is measured in ampere/hours (or
milliampere/hours), usually stamped or printed somewhere on the battery pack,
something like ‘2Ah’ or ‘500mAh’.
It is worth knowing that there are several different types of
rechargeable battery. The best -- at the moment -- is lithium-ion (Li-ion),
which has the highest power to weight ratio (power density), and can endure
so-called ‘top-up’ charging without damage. If you have a choice opt for the
device with a Li-ion battery, but expect to pay a healthy premium. Nickel Metal
Hydride (NiMh) rechargeable batteries are generally larger and heavier for a
given capacity but they’re also a lot cheaper, can also withstand top-up and
‘fast’ charging. Nickel-cadmium (NiCd or ‘nicad’) batteries usually have lowest
capacities and they don’t take kindly to top-up charging but they are normally
quite cheap and can be fast-charged.
Larger devices, like laptops and those using Li-ion batteries
should always travel with their own chargers but it should be possible to
rationalise your power supplies and chargers for smaller devices that use NiMh
or Nicad batteries with one ‘universal’ type charger. However it is very
important to make sure it has the correct voltage output, current rating and
connecting plug. Unfortunately there is no agreed standard for DC charger
connections; many products use a cylindrical style plug but there are several
different sizes and the polarity of the plug also varies, so it is important to
do a little research first. Universal ‘Travel’ chargers with switchable voltage
outputs and multi-way adaptor plugs are available from electronics stores like
Maplin (www.maplin.co.uk) for around
£40.
If you can’t cut down on the number of chargers you should at
least be able to reduce the number of mains leads. Most chargers use the
standard two-pin figure-of-8 or ‘Telefunken’ type connection so where possible
take just the one mains lead. Another quick and easy clutter-cutting trick is to
shorten the lead to a foot or less by cutting the cable and fitting a new plug.
Some Ericsson phone chargers come with detachable UK three-pin and continental
two-pin mains plugs with a moulded Telefunken plug on the back. These are worth
their weight in gold and fit many lightweight chargers.
Finally, if you’re flying long haul with a laptop you can
speed your transit (and others) by putting the machine into standby or sleep
mode just before you go through the customs and security checks. If you are
asked to power up the machine you can quickly show it working, without having to
wait for it to boot fully, which will save time, and power.
Next week –
JARGON FILTER
FAST CHARGING
Rapidly charging a battery pack, typically in an hour or so,
however, unless the charging current is very carefully controlled this can
result in a shortened life and/or reduce capacity. Normal charge times for nicad
and NiMh batteries/cells is in the order of 14-hours, the so-called ‘overnight’
rate
POWER DENSITY
The amount of energy a battery can store in relation to its
physical size and weight
TOP UP CHARGING
Charging a re-chargeable battery before it has been
completely drained. Some battery types (i.e. nicads), develop a ‘memory’ or
‘cell imbalance’ that over time prevents them from retaining a full charge
TOP TIP
If you are taking a laptop, organiser or mobile phone with
email access on a trip create a small document file containing important
numbers, names and contacts that might come in useful in case of an emergency,
such as your passport number and local telephone numbers for your insurance
company etc. You can disguise or hide the numbers in an email or letter, so that
no one else can understand them. Give the file an innocuous name – e.g.
‘trav126.txt’ -- and hide it in an unrelated folder. Before you leave send the
file to yourself in the form of an email, so you can access it, from an Internet
café for instance, using an email web server (e.g. www.mail2web.com) if your equipment is lost
or stolen.
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