GPS Unit
Most GPS receivers are easy to setup and operate. User guide manuals usually have easy instructions that will get you started. These instructions include how to install the battery, how to determine your initial current position and how to input a destination. When you first turn on your GPS unit at a totally new location, it helps to input an estimate of your approximate location (like the coordinates of the nearest large city). This helps your unit know where the satellites are supposed to be, so that it takes less time to pinpoint your position. If your unit starts out “cold”, or you are no where near your last stored position, it may take up to 15 minutes to find its place on earth. However, if you give it a little hint, or you are near where you were the last time the GPS unit was on, it usually takes no more than 3-5 minutes to fix your position. Once again, please read your user guide manual for actual instructions.
How to Input Data
There are different ways to input numbers and letters into your GPS unit. Most units use arrows or buttons to move between functions and screens. Some units use these arrows to select a number or letter (for a location name or coordinate). The up arrow will advance thru the alphabet and 10 digits. After you find the value you want, you just enter it and proceed to the next letter. Other GPS units have actual alphanumeric keys, like your phone, to make it easier to enter names and numbers.
TYPES OF GPS FEATURES:
There are several buttons on the face of most GPS units that, when pressed, route you to various operating options. They may have different names, but they have similar functions. They may allow you to view a navigation screen, status satellite signal availability, review your positions list, or determine your position relative to a selected destination. The following explains what some of these options are:
Position:
This screen displays present position, elevation, and time of day. If a destination or route is active, it may also indicate direction toward the destination.
Pointer:
If there is an active destination or route, this screen will point to that location and provide bearing, distance and time to go to get there.
Navigation:
If you are moving, the current heading and speed are displayed. If a destination or route is active, this screen gives bearing and distance to that position. It also provides an indicator if you are on or off course.
Plotter:
This screen provides a track history of the route traveled, and the bearing and distance to the listed destination.
Satellite Status:
Most GPS units have a feature to display how many satellites it is tracking and what level of satellite signal strength it is receiving. If more than 4 satellites are visible, the receiver will choose the best 4 satellites, based on signal strength and triangulation angle.
Landmark or Waypoint List:
You usually can view the positions you have stored in memory so that you can rename or delete them, or plan a route. You can sometimes add icons (a FISH or Car or TREE, etc), to distinguish important waypoints.
Setup Options:
Most units allow you to choose units, time system, the coordinate system, map datum, and true or magnetic north. There may also be options to receive Differential GPS signals, or download data.
Distance to (GO TO):
This feature allows you to select a stored position, and make it active. Then it provides the bearing and distance to that location, from where you are.
Cross-Track Error (XTE):
If you have selected a position or waypoint that you wish to travel to, and make it a route or leg, then as you move, the cross-tract error indicator will tell you if you are on the direct line between your start and stop point, or if you are left or right of that path, by 0.1 mile or 20 miles, depending on the scale you choose.
Last Fix:
While your GPS portable navigator is turned on, it will continually update its location every second or two. Your unit may regularly store this last fix location in memory every 10-30 minutes, and refer to it when you backtrack your route, or restart your unit.
Sunrise/Sunset Time:
Some GPS units can provide you sunrise and sunset time for a given day at a given position. This can help you plan to maximize activity in available daylight, or just catch a great sunset shot.
