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Ask Rick 030, 02/03/09 & Houston 120, 14/03/09
Roaming in the USA
I am planning a trip to Florida and would like to take a
laptop with me for Internet and Skype use. The villa where I will be staying
has broadband but not Wi-Fi. As yet I
cannot establish whether there is a wireless hotspot close by. Would a USB modem for mobile broadband work
outside the UK and how close to a hot spot would it need to be? Can you suggest a solution?
Ruth Martindale, by email
You should be able to connect your laptop to the broadband
modem using a LAN/Ethernet cable; these are widely available from computer
stores, here and in the US, for around £5.00. Simply plug the cable you’re your
PC’s LAN socket, and the other end goes to the corresponding socket on the back
of the modem. Once connected XP and Vista will immediately recognise the modem
and the Internet connection and you’ll be online.
Mobile broadband in the US lags some way behind the UK and
Europe. Older, slower 2G services are fairly widely available but you’ll need a
specialised mobile modem or triband cellphone with data capability and PC
connectivity, plus a suitable connecting lead. 3G services are still patchy and
quite expensive, especially if you are ‘roaming’ on your UK mobile broadband
contract. There are ways to cut costs, such as using an ‘unlocked’ triband or
quadband modem with a SIM and pay-as-you-go data package purchased when you get
there, if you can find one, but it’s a bit of a minefield at the moment so
unless you are going to be visiting the US on a regular basis, and know you’ll
be in an area with good coverage I would stick with the villa’s broadband.
Providing your laptop has wi-fi capability you should be able to connect to any
free hotspot in range (typically 25 – 30 metres) and there are plenty of them,
just Google ‘free wi-fi florida’ for locations.
Google Maps Blindspot
I recently had a nasty accident negotiating a bend, going
uphill, in the rain (86mm in 24 hours - I am in Spain!). I wanted to make a printout of the scene of
the accident showing all the white lines, the arrows on the road and where I
finished up in a gully having traversed, travelling backwards, the lane of
oncoming traffic. I had a brilliant idea of zooming in on a satellite images
from Google maps. When I attempted to print the image the map all that came out
was the actual road map. So I emailed
the satellite image to myself and again it came out as the actual map. Do you
know of any way round this?
Ernest Bulitude, by email
Unfortunately you
can't print satellite images in Google Maps. There doesn’t seem to be
any good reason for this and it’s a bit odd in view of the fact that there are
no such restrictions in Google Earth (http://earth.google.com/),
which as far as I’m aware uses the same satellite image database. When you
click the print icon in Google Earth you get whatever is showing on
the screen.
Guilty As Charged
Why is it that
rechargeable batteries run down in a relatively short space of time, even if
they’re not being used, and stored properly? To what extent does the quality of
the battery make a difference? How many charges should I expect from a set of
batteries?
Peter Martin,
East Yorkshire
All rechargeable
batteries self-discharge and the speed at which they do so depends on a number
of factors, including the chemistry and the cell’s internal resistance. Lithium
Ion (Ion) batteries usually have quite good long-term storage characteristics
and this can be from a few weeks to several months. Nickel Cadmium (NiCad) and
Nickel Metal Hydride (NiMh) cells can lose between 1 and 4 percent of their
charge every day. However, a lot also depends on the quality of the cells, the
pack construction and the device they’re powering.
Even when switched
off many laptops and mobile phones, for example, can still consume a few micro
amps to several milliamps of power to keep an internal clock running or
maintain data on ‘volatile’ memory chips. Self-discharge rates also increase
with temperature and the age of the battery.
Li-Ion batteries
degrade from the day they're made and there can be a significant drop in
capacity, as much as 50 percent, in as few as 500 charge/discharge cycles,
though it’s getting better all the time. NiCad and Nickel Metal Hydride (NiMh)
cells can typically go through 1000 charge cycles before the rot sets in, and
NiCad battery packs also suffer from the so-called ‘memory’ effects or cell
imbalance. This happens when one or more cells in the pack retain a
higher charge than the others, which fools the charger into delivering an
incomplete charge.
Don’t be Dense
I appear to have bought,
online, 1Gb of RAM, which runs as 512k. It seems to be ‘high density’ RAM, a
version unknown to me. Is this common and how can a purchaser know what they
are buying?
Gordon Lee, by email
High-density RAM modules
have been appearing on ebay at enticingly low prices and I suspect quite a few
people have been caught out. Virtually all PCs are designed to work with Low
Density RAM modules. High Density RAM works in a slightly different way and is
designed for specialist applications, like server computers and until recently
they have not been available in the consumer marketplace, so it wasn’t a
problem. The problem is the two types look almost identical. In fact the only
way to tell them apart is from the coding on the labels. These can be
difficult, if not impossible if all you have to go on is a fuzzy picture and a
vague description, so the best advice, as always, is to only buy from reputable
sources. Unless you can persuade the seller to take them back, or they were
knowingly miss-sold to you then I’m afraid there’s not much you can do. There’s
a helpful guide to identifying the different density types in ebay Reviews at: http://tinyurl.com/6knk63.
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© R. Maybury 2009 0902
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