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BOOT CAMP 117
LAPTOPS AND CELLPHONES Part 1
Believe it or not surfing the Internet, exchanging email and
faxing on a desktop PC is relatively easy nowadays. That’s cold comfort if you’re
struggling to configure Windows, a troublesome browser program or dealing with an
awkward Internet Service Provider, but even in the darkest moments of your
battle to get on-line you will not have experienced one tenth the misery and
suffering of someone attempting to establish a connection to the Internet using
a laptop PC and a cellular mobile phone!
Of course there are exceptions and a lucky few manage to get
everything up and running first time and it has to be said that it’s a lot
easier than it used to be, but the plain fact is current mobile phone
technology is simply not up to the job and all attempts to make it work involve
fudge and compromise. This week we’ll look at why it is so difficult and the
sort of kit you need; next week how to make it all work.
There are two fundamental problems. Firstly the GSM and PCN digital
cellphone networks we have in the UK were never designed to carry high-speed data
traffic. The best they can manage at the moment is 9600 bits per second (bps) or
between a quarter and a sixth the speed of a normal landline, and that’s on a
very good day with the wind in the right direction! Even if you manage to get a
strong stable signal web pages can still take an age to download. With peak
time call charges on some tariffs costing 50p or more a minute, web surfing can
be a horrifically expensive business so unless someone else is paying for the
calls it’s best confined to plain text emailing.
Second, there are the hoops that you have to go through, to connect
a cellphone to a PC. Conventional modems are no use; they’re designed to
convert PC data into audible tones that can be sent down analogue telephone
lines. Unfortunately you can’t simply squirt data from a PC into a phone, and
to make matters worse there’s no such thing as standardisation, when it comes
to the connectors on mobile phones, and PCs for that matter.
Moves are afoot to increase cellular telephone data transfer
rates. Orange is upgrading its network to operate at up to 28,000 bps by
stripping out a lot of the error correction using a technique known as High Speed
Circuit Switched Data (HSCSD). The other networks are testing a system called General
Packet Radio Service (GPRS), which has a claimed top speed of more than 40000 bps
and the prospect of permanent data connection. Both are still some way off
moreover it’s by no means certain that they will work with existing phones and
you can be sure it will involve a good deal of extra expense.
PC to phone connections are a nightmare and the cellphone in
question has to be ‘data compatible’. Most are these days but if yours is more
than three or four years old or a very
basic model on a low cost tariff it might be time to upgrade. As far as the PC
is concerned the most straightforward option is a Windows or Apple Mac laptop
or notebook that can run all of your usual browser and email software. The next
best thing is a Windows CE or Psion palmtop PC. Windows CE includes cut-down or
‘pocket’ versions of Internet Explorer and Outlook Express, which makes life
easier if you’re accustomed to Windows applications; Psion palmtops are also
very simple to use but only the Series 5 and 7 models are email and Internet friendly.
It is also possible to connect most keyboard-less organisers or PDAs (personal
digital assistants) to mobile phones but that’s another scary subject for
another day…
In order to physically connect a mobile phone to a PC the
latter needs a PCMCIA (PC Card) slot or a serial port. The former is for a GSM
or PCN ‘modem’ card, a lead from the card goes to the phone’s accessory socket.
A card and cable can be quite expensive, between £150 and £250 is not uncommon,
depending on the make and model of phone, how old it is and how well supported
it is by third party accessory manufacturers. Be warned that you’ll probably have
to chuck the whole lot away if you change or upgrade your phone due to the lack
of standardisation on phone connectors and operating software.
A recent and more cost-effective alternative to the PC card
is a ‘Soft Modem’. This is essentially a PC program that replicates the actions
of a modem in software. They tend to be a lot cheaper than PC cards (typically £75
to £120, including the serial port to cellphone connecting lead), and they don’t
consume anything like the power of a PC card modem (see Tip of the Week). The
downside is that all of the cellphone soft modems that we are aware of are written
for Windows 95/98 and Windows CE machines, it looks as though Mac users will
have to wait.
On a few recent phones you can do away with the cable link
altogether, these models have infra-red ports compatible with the IrDA ports on
a lot of laptop, notebook and palmtop PCs. Specialist software is usually needed
to utilise the link so check on the cost of this first as in some instances it
can be almost as expensive as a PC Card or soft modem. One last thought. IR
links sound like a great idea but they can be quite difficult to use in
practice since the phone has to be carefully aligned to the PC’s IR window – a
tricky balancing act if they’re both on your lap – and this may not be the best
position for the phone if you’re in a marginal signal area.
Next week – Laptops and mobile phones Part 2 -- getting it
to work
JARGON FILTER
GSM
Global System for Mobile communications – digital cellular
telephone system used by the Cellnet and Vodaphone networks in the UK and in more
than 100 other countries
PCMCIA
Personal Computer Memory Card International Association. Body
responsible for PC card standards. PC cards are credit card sized modules (but
a little thicker) used in laptops for modems, memory expansion and other
peripherals
PCN
Personal Communications Network (aka GSM 1800) digital
cellular telephone system used by Orange, One 2 One and Virgin in the UK and more
than 100 other countries
TOP TIP
If you are using a laptop or notebook with a PC card modem to
connect to the Internet – via land-line or a mobile phone -- then make sure you
remove the card when it is not being used, especially if you are running the PC
on battery power. PC cards draw power from the PC’s battery, but what the instructions
usually fail to mention is that the card is permanently on and draining the
battery all of the time it’s in the slot.
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