How to Buy a Handheld GPS System

Forget a compass, which only shows you north, south, east or west. A handheld GPS (global positioning system) navigation device can tell you within feet where you are and what route to take to get to a destination. And these products are so small they can fit inside a pocket.

Things You'll Need

• GPS Carrying Case
• Handheld GPS Navigation System

Instructions

1. Consider the size of the unit. Do you want to slip a unit into your pocket? Various carrying cases are available.

2. Choose a system that has multi-parallel channels. This ensures that several satellites are tracking you at one time rather than just one. You get faster fixes in difficult conditions.

3. Select a system that can store 100 or more way points. These are geographic points that can be used as markers.

4. Pick a system that can give the distance and direction of a point from your current position.

5. Choose a system that can store several routes.

6. Pick a system that is capable of using UTM grid data maps or local grid maps. Make certain that the system can use the common datums used worldwide.

7. Make sure the unit is rugged and waterproof.

8. Make certain that it has a backlit display. This is essential if you intend to do your hiking or bike riding at night.

9. Make certain that the battery life of the unit is sufficient for your travels.

10. Have the salesperson show you how to work the unit and then work it yourself.

Tips & Warnings

• Instead of relying on the Earth's magnetic field as a compass does, the GPS navigation system uses a host of satellites that orbit the Earth. The satellites communicate with land-based stations to always know their own positions in space. Your GPS unit communicates with the satellites to determine your distance from the satellites - and thus your position on the Earth.

• Purchase and carry extra batteries for use when needed.