Computing your position using a handheld GPS unit
Handheld GPS Units equip you with the navigation tools to arrive at your destination whether you’re hiking, camping or geocaching. Whatever the reason you use your handheld GPS unit you’re going to want to start by computing your position.
The basic operation of a GPS whether you are using a PDA handheld or a marine GPS is to use the GPS satellites to compute your position. This is done internally in the software of your handheld GPS system. The most important thing to remember is that you need to give your GPS system a clear view of the sky so that it can receive the signals from the satellites.
If your GPS navigation system is having problems make sure that the antenna isn’t covered by your hand or other objects, that the antenna isn’t pointing down, that there is a clear view of the sky and that the satellite signals are not being blocked by buildings or other large obstructions.
If in doubt have a look at the status of the satellites and their signal strength. On the eXplorist handheld unit this is done by switch to the Satellite Status screen. Where you can see a graphic of the satellites and their relative signal strength. You will usually need at least three satellites with good signal strength to compute your position. If you have four or more satellites then you will be able to add elevation to your position fix.
