Lowrance electronic GlobalMap 100 - Manual (Page 11)

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error is only an estimate, 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 is flashing, then the unit has not locked onto the
satellites, and the number shown is not valid.
The fix indicator on the left center shows either 2D or 3D. A 2D fix means
the unit has locked onto three satellites and has calculated its position. A
3D fix means the unit has locked onto at least four satellites and has
calculated both the position and altitude. (Remember, it takes three satel-
lites to determine the position - four to determine position and altitude.) If
neither 2D nor 3D are showing, then the unit doesn’t have the position or
altitude.
A battery level indicator on the lower right side of the screen shows ap-
proximately how much life is in the batteries. This runs from “F” (fully
charged) to “E” (expired).
A light bulb indicator at the top right corner of the screen appears when
the backlights are on.
Finding Your Position
Auto Search
To lock onto the satellites, the GPS receiver needs to know it’s current
position, local time, and date. (Elevation (altitude) is also used in the equa-
tion, but it’s rarely required to determine a position.) It needs this data so
that it can calculate which satellites should be in view. It then searches for
only those satellites. When your GPS receiver is turned on for the first
time, it doesn’t know what your position or elevation (altitude) is. It does
know the current UTC time and date since these were programmed into it
at the factory and an internal clock keeps the time while the unit is turned
off. It begins searching for the satellites using the above data that it ac-
quired the last time it was turned on. This probably was at the Lowrance
factory. Since it’s almost certain that you’re not at the Lowrance factory,
it’s probably looking for the wrong satellites. If it doesn’t find the satellites
it’s looking for after five minutes, it switches to Auto Search. The receiver
looks for any satellite in the sky. Due to advanced technology, the auto
search time has shrunk to about five minutes, so the longest time you
should ever have to wait is ten minutes from the time you turn the unit on
until it locks onto the satellites and shows a position. Once the unit locks
onto the satellites, it should take less than a minute to find your position
the next time it’s turned on, provided you haven’t moved more than ap-
proximately 100 miles from the last location it was used.