How sat nav systems work
Sat nav systems make use of a network of
satellites called GPS. These satellites orbit the Earth in known positions.
By comparing the signal from several of these satellites, your sat nav
can calculate where it is on the Earth's surface – often to within
a few metres.
Sat navs allow you to plan your route in a variety of ways – entering a postcode,
address, even a nearby landmark. The sat nav will calculate the shortest
route to your destination and guide you every step of the way.
Which type of sat nav is right for me?
Sat navs come in varying sizes, starting at 3.5in. If you think you’ll use it often and that you’ll benefit from a larger screen, you should definitely consider 4.3in or 5in.
Larger screens are clearer and make using the touch screen even easier. They also allow you to view a greater area of the map at any one time. As you can see below there are various maps to choose depending on whether you want to use your sat nav in the UK or when you travel abroad.
| UK & ROI | Western Europe or Full Europe. | North America and Canada. |
| UK and ROI mapping sat navs are ideal for business users, day trips and those who travel regularly domestically. Think about upgrading to a
European sat nav as the majority of European mapping sat navs also feature street level mapping of UK and ROI. |
Europe mapping sat navs are ideal for those who holiday or travel regularly on the continent. If you travel to Eastern Europe you need Full European mapping. |
USA and Canada mapping sat nav is pre-loaded with the latest and most accurate maps, this sat nav is ideal for those who holiday or travel for business regularly to North America and Canada. |
Key features to look out for
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Traffic and routing |
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Safety cameras |
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Points of interest
This is great when you’re in a place you don’t know very well. On longer journeys this feature can be used to plan breaks. |
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Bluetooth |
| Touch screen |
You can choose options on your sat nav by touching the screen with a finger – easier than a keyboard, especially when you're driving. |
| 2D/3D mapping | The sat nav can display both flat 2D maps (as you'd see on a printed road map) and 3D views that look more like the view from your car. |
| Postcode search |
Allows you to search for your destination by postcode. |
| Mapping loaded |
The type of map on the sat nav system. There are several, such as 21 Euro (which covers most of Europe) and UK/ROI (Britain and Ireland). |
What to look for when subscribing
To keep the maps in your sat nav up to date, you'll
need a subscription. (Many sat navs offer you several months' free service,
after which you pay a small fee per month). It's a small price to pay for
having information about new petrol stations, closed or new roads, and
speed camera locations at your fingertips.
Traffic updates reach your sat nav in one of two ways. The radio system,
called Traffic Messaging Channel (TMC) is usually free, while updates through
your mobile phone (connected to your sat nav wirelessly) need a subscription.
There's a bonus: some Bluetooth sat navs can help you make hands-free calls
or even read your text messages to you!




