Eagle Electronics 642c iGPS manual

Models: 642c iGPS

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Satellite Status Page. The first figure (left) indicates unit has not locked on to any satellites and does not have a fix on its position. The second figure (right) shows satellite lock-on with a 3D position acquired (lati- tude, longitude and altitude), and WAAS reception.

This screen shows a graphical view of the satellites that are in view. Each satellite is shown on the circular chart relative to your position. The point in the center of the chart is directly overhead. The small inner ring represents 45° above the horizon and the large ring represents the horizon. North is at the top of the screen. You can use this to see which satellites are obstructed by obstacles in your immediate area if the unit is facing north.

The GPS receiver is tracking satellites that are in bold type. The re- ceiver hasn't locked onto a satellite if the number is grayed out, there- fore it isn't being used to solve the position.

Beneath the circular graph are the bar graphs, one for each satellite in view. Since the unit has twelve channels, it can dedicate one channel per visible satellite. The taller the bar on the graph, the better the unit is receiving the signals from the satellite.

NOTE:

One of the data display options for the Satellite Status page is "Po- sition Error" (horizontal position error), which can appear in one of the page's data boxes. Position Error will show you the expected er- ror from a benchmark location. In other words, if the Position Error box shows 50 feet, then the position shown by the unit is estimated to be within 50 feet of the actual location.

This also gives you an indicator of the fix quality the unit currently has. The smaller the position error number, the better (and more ac- curate) the fix is. If the position error flashes dashes, then the unit hasn't locked onto the satellites, and the number shown isn't valid. (For details, see Customize Page Displays, on page 71.)

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Eagle Electronics 642c iGPS manual