Using a GPS device

GPS 

A GPS (Global Positioning System) device is a hand-held receiver that picks up signals from satellites circling the earth, enabling you to locate your current position to an accuracy of 10-20m. Most modern GPS devices can then show that position on a map and, if you have stored a pre-programmed route, help you navigate along it.

GPS devices are similar to the SatNav devices now used by many drivers. However, while SatNavs use information about the road network to navigate step by step towards your destination, there is no equivalent “dataset” of information about off-road paths and access areas for walkers. So although the GPS can help you find your way, it won’t give step by step instructions like SatNavs.

Many walkers find GPS devices a useful gadget but they aren’t a substitute for traditional maps and compasses in outdoor navigation. This is because:

  • To use a GPS successfully you will already need to have a reasonable understanding and experience of map reading and navigation.
  • GPS can’t be relied upon, especially in remote areas where accurate navigation is safety critical. The signal may fail in particular conditions, the device may fail, or the batteries may run flat, particularly if you’re unexpectedly delayed.

Some things to bear in mind when buying a GPS

  • The more channels a receiver has the more chance the unit will find enough satellites to pinpoint your location accurately.
  • An external power socket is a useful feature, for example if you want to save power when using your GPS in a car connected to a mobile charger or cigarette lighter, or use it with a solar powered charger.
  • Good battery life is essential – and make sure you pack some spares.
  • A good screen that displays quality colour will make the map more readable. Large screens are easier to read but are likely to use more battery power.
  • Will the buttons work if you’re wearing gloves? Will they be pushed accidentally when you put the unit in your pocket?
  • If you want to store lots of routes then you will need plenty of memory space.
  • Compatibility. Will your GPS connect to your computer (most will by using USB connections), and will it integrate with any electronic maps and mapping packages you want to use? Will it accept routes from your favourite online sites?
  • Is it also equipped with a magnetic compass? This is a useful feature to have as a failsafe it connection with the satellite fails.
Photo: © David Fulmer