Lowrance GlobalMap 1600, Installation And Operation Instructions Manual

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13
To turn the unit on, simply press the PWR key. A
GPS logo screen appears, then the screen simi-
lar to the one at right appears. Read the mes-
sage on the screen, then press the EXIT key to
erase it or wait a few seconds and it automati-
cally clears. The screen shown below appears
next.
This screen appears each time you turn the unit
on. It shows a graphical view of the satellites that
are in view. Each satellite is shown on the circu-
lar 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 you hold the unit facing
north.
The GPS receiver is tracking satellites that are surrounded by a black
box. The receiver hasn't locked onto a satellite if it's number isn't sur-
rounded by a box, therefore 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. Therefore, if only six satellites are visible, only six bar
charts show at the bottom of the screen. The wider the bar on the graph,
the better the unit is receiving the signals from the satellite.
The number in the upper left corner is the “expected horizontal position
error” or expected error from a benchmark location. In other words, if the
expected error shows 50 feet, then the position shown by the unit is esti-
mated to be within 50 feet of the actual location. However, this number is
only valid if you’re using DGPS or if S/A is turned off. Due to S/A, the
accuracy can only be less than 100 meters, 95% of the time, per U.S.
government specifications. Although the expected error is not accurate
unless you have a DGPS receiver, it does give you an indicator of the fix
quality the unit currently has. The smaller the expected error number, the
better (and more accurate) the fix is. If the expected error flashes, then
the unit hasn't locked onto the satellites, and the number shown isn't valid.
A light bulb indicator at the top right corner of the screen appears when
the backlights are on.