GPS

What is it and how does it work?
A GPS (Global Positioning System) receiver uses signals from a network of US military satellites to accurately calculate it’s latitude, longitude and altitude anywhere on earth. If you are using one in the UK it can give you your position as an OS grid reference.

What are it’s benefits?

Under the right conditions, even a basic handheld GPS receiver will be able to calculate your position to within about 10 meters, in about 15 seconds, day or night, whatever the weather.
Once you start moving, the GPS receiver can provide a wealth of other information including your speed, direction, journey time, average speed, and distance travelled.
If you input the grid reference of a location you wish to travel to, the GPS receiver will guide you exactly to that point, no matter how may de-tours you make. It will continually re-calculate the bearing, distance and time to your destination, based on your current location and speed of travel.
If you have a PC, the correct software and a connection cable, you can plan your route on the PC and download this route to the GPS receiver. Once on a route, the GPS receiver will guide you from waypoint to waypoint, automatically directing you to the next once one is reached.

What are it’s drawbacks?

The satellite signals are easily subject to interference (which reduces accuracy), and can sometimes be completely blocked by mountains, dense trees, tall buildings, etc.
It will only work for as long as the batteries last! How long they last depends on use - it will typically be about 10 to 22 hours.
Most units only have a ‘sense of direction’ once you start moving. They can easily calculate the bearing you need to travel in to reach a waypoint, but have no idea in which direction that bearing is.
'TracBack' and 'Track-to-route' features (which will guide you back home exactly the way you have come) only work if your GPS has been switched on continuously since you left your starting point.
Waiting until you are lost on a wet, cold, cloud covered hillside is not a good time to start learning how to use a GPS or forgetting how to use it.
A GPS receiver can tell you where you are, and can direct you in a straight line to any location you ask it to, but it has no knowledge of the surrounding terrain - it may well direct you through bogs, into lakes, and even over cliffs if they happen to be on that course. Although more sophisticated receivers are able to direct you along roads, none can currently follow footpaths or avoid natural obstacles.
Due to these limitations, a GPS receiver is no substitute to a map and compass and traditional navigation skills. They are potentially a fantastic aid to navigation, but should never be relied on solely.

What does it cost?
Basic units now start at under £100. More money will get you more features like extra navigation functions, on-screen maps, a built-in compass and altimeter, more memory capacity for storing waypoints, etc.

How do I find out more?

[ www.garmin.com ] [ www.magellangps.com ]

Or escape2 on Freefone 0800 0286 836

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