Bluetooth
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ets make no bones about it –
having a Bluetooth device is cool!
But it’s a bit pointless, after all, you need at least two Bluetooth
devices for it to do anything, right?
Bluetooth is a universal communications standard, specifically designed
for “personal area networks,” i.e. for small networks about ones’ person! The designers really did have the idea of a
Bluetooth-enabled headset, cell ‘phone, PDA and MP3 player all living in your
pockets.
Two Classes
There are currently two classes of
Bluetooth radio services – class one being the more sensitive, longer ranged
radio service whereas class two has less sensitivity and a shorter range. Generally speaking, The shorter the shorter
the range, the lower the power consumption of the device and the last
thing you want or need is a Bluetooth radio that drains the battery in an hour.
Bluetooth Functionality
Palm gave the Tungsten T range
onboard Bluetooth, Charlie’s iPAQ has the Bluetooth radio and all of my mobile ‘phones
from my old stolen Nokia 6310i. I’ve
also used a Palm
Using Bluetooth, all of the above
devices (with the exception of the earpiece) can communicate with one
another. This by itself is useful,
however what is more useful is how easily they communicate with one
another. Providing you know the PINs for
the various devices, you’re all set to start communicating between the units.
The Palm
Palm’s tiny little Bluetooth SD
I/O card works flawlessly with both the Palm m515 and Palm
m130 I’ve tried it on, and of course it’ll also work with the Palm m125,
m500 and m505.
Using Your Bluetooth PDA with Your
Bluetooth Cell ‘Phone
Using your Bluetooth-enabled
PalmOS or PocketPC handheld to connect with a cell ‘phone is a logical
extension of the PDA. Although the
natural assumption is that the Bluetooth connection is for using the cell
‘phone as a modem, the reality is that a connection between the two devices is
rather more useful. If you’ve ever
tapped in a whole bunch of numbers into your cell ‘phone, only to have to
re-tap them into another cell ‘phone, and then if you ever had the handset lost
or stolen... You’ll be seeing where I’m
coming from (unless, of course, you’re in the habit of losing your PDA).
Edit: well this happened to
me! My Nokia 6310i handset was stolen by
some thieving scumbag, but fortunately I didn’t lose all that much
information. The replacement device, the
SPV also has Bluetooth, but it
also has most of the PDA functionality, too.
Using the Bluetooth connection,
it’s entirely possible to use the PDA to dial numbers, receive and send SMS
messages, as well as using the ‘phone as a modem.
Synchronising Your PDA
using Bluetooth
Now if you thought connecting to a
Bluetooth-enabled cell ‘phone was cool, connecting to your desktop computer is
quite special! Both PalmOS and PocketPC
2002 will happily connect to the desktop via Bluetooth and it’s simply a case
of configuring the Hotsync Manager or ActiveSync respectively to use the
Bluetooth adapter as a virtual serial (or COM) port.
Whilst connection speed is not especially
quick, being somewhere between a serial connection and a USB connection, it’s
certainly fast enough for most purposes.
And it’s still cool to Hotsync my PDA to the desktop in Dervy
Headquarters upstairs whilst in the living room downstairs.
Bluetooth Notification
One additional feature of
Bluetooth-enabled devices is that it has finally given manufacturers an
excuse to use bright blue LEDs to show the world that you have Bluetooth. Although at first this is a welcome feature,
it seems that the majority of blue LEDs are superbright and at night, the
effect can be quite dazzling.
These three images show the
standard dull green “service active” lamp, the bright blue Bluetooth lamp, and
no lamp lit.
Bluetooth Power Consumption
From a top down approach, most
devices have three broad Bluetooth modes - off, on and discoverable. Yes, I know some clever hardware boffin
will tell me that are four modes of operation, but this isn’t quite the place
to discuss one second sniffing...
When off, the associated hardware is simply deactivated and there is no
additional power consumption. When
switched on, this means that the Bluetooth hardware can communicate with other
known, or bonded, Bluetooth devices but it will refuse communication with unknown
Bluetooth devices. In discoverable mode,
this means that the Bluetooth hardware will seek out and interrogate all other
hardware within range.
It is reported that Bluetooth
hardware uses more power when in discoverable mode, although at the time of
writing I have insufficient data to confirm, or otherwise, this idea. It is also impossible to ascertain just how
much additional power the Bluetooth hardware uses, since this depends very much
on the device in question, how it is being used and the battery capacity of the
unit. Taking the PalmOS hardware I’ve
used in the past, using the Palm Bluetooth card with the Palm m130 will have significantly less impact on the
battery compared to using it with the Palm
m515 and keeping the backlight turned off.
Keeping the Bluetooth radio switched on all of the time with the Tungsten T3 hammers battery life when the device is
otherwise in standby mode.
However, when Bluetooth is used in
the absence of any other Bluetooth-enabled device, the power consumption of the
unit is significantly increased as the device essentially goes on the hunt for
like-equipped fellows. When two or more
devices are within range, power consumption is significantly reduced. If this doesn’t make any sense, think about
how much louder you would have to shout to an office colleague you didn’t know
if or she were a few rooms down because you couldn’t see that far, rather than
if he or she were next to you.
A Cool Gadget?
Now why hasn’t this been bought to
market yet? Or has it? Well, I’m sure it has, but I’ve yet to see it
advertised as such.
Given that modern cell ‘phones are
getting more and more complicated - with built-in Bluetooth, cameras,
calendars, tasks and note lists, plus Java games, colour screens, and a whole
lot more besides, is there still a market for a simple ‘phone?
I would like a simple ‘phone! Why?
Because my PDA (well, okay then, because my entourage of PDAs!)
provides me 
with everything else
need.
GSM technology has reached the
point whereby the core elements of a cell ‘phone can be shrunk to the size of a
ten pence piece.
So why not incorporate the
necessary antenna and battery into a headset?
Okay, well yeah I suppose there’s
this risk of GSM electromagnetic waves frying our brains, but if that doesn’t
get us, I’m sure Bluetooth, WiFi, television, radio, microwaves, heh everything
else will get me in the end!
So why not incorporate the GSM
‘phone into an earpiece, bungle it up with a Bluetooth unit, and then control
the ‘phone via the PDA.
So, c’mon people, what’s wrong
with that?
SPV Bluetooth
One of the reasons why I bought
the Orange SPV E200 is because the
device has onboard Bluetooth connectivity.
This meant I could use the handset in conjunction with my Jabra BT100
headset, and this in turn dramatically increases how much I can use the ‘phone,
especially when driving.
With the BT100 headset, I can
answer calls by depressing the multifunction button on the unit. Thus should somebody ring me when I’m driving
I’m potentially able to talk to them (of course, being able to and actually
doing so are two different things).
However, this functionality comes
at a cost. For most devices, it’s a
mixture of size, weight and battery longevity.
The SPV E200 also has these compromises.
It is slightly larger than the previous SPV models, although it feels
the same weight. And when the Bluetooth
radio is turned on, battery longevity takes a hit.
It is difficult to assess the
difference in battery life when the SPV needs charging each and every day. However, I have noticed that if I keep the
handset within range of another Bluetooth-enabled device that it is aware of,
the battery does last significantly longer.
This must be because the power consumption of the Bluetooth radio in
search mode is higher than that of it when maintaining a connection.
However, battery longevity can
become a problem on days out, especially when one makes use of the SPV for both
Bluetooth-headset calls and conventional calls.
Whilst admittedly, the device was not quite fully charged, I only
managed fourteen hours of (for me, heavy) use until the second “Low
Battery” warning flicked up.
Is this a problem? Well, not really providing I accept that I’m
going to have to charge the SPV every day anyway. But it will mean that we’re going to have
some kind of charger with us for when we go camping - as a last resort we
already have the option of Kermit’s voltage inverter and the 240v charger unit.