Lowrance electronic Hunt GPS Receiver User Manual


 
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the screen is 100 miles in diameter (same as the zoom range). The sec-
ond smaller ring is 50 miles in diameter (always 1/2 the zoom range).
The distance from your current position to the smaller ring (the ring's
radius) is 25 miles (always 1/4 the zoom range). With the arrow keys
and map cursor, you can scroll the map to see the third and fourth
rings. In this example, the distance to the third ring is 75 miles and
distance to the fourth ring is 100 miles from your current position.
To set range rings: Press
MENU| to MAP DATA|ENT. Press to RANGE
RINGS. With the option highlighted, press ENT to check it (turn on) and
uncheck it (turn off.) After the option is set, press
EXIT repeatedly to
return to the main page display.
To set Lat/Lon Grid Lines: Press
MENU| to MAP DATA|ENT. Press
to
LAT/LON GRID LINES. With the option highlighted, press ENT to check it
(turn on) and uncheck it (turn off.) After the option is set, press
EXIT
repeatedly to return to the main page display.
Map Datum Selection
Maps and charts are based on a survey of the area that's covered by the
map or chart. These surveys are called Datums. Maps that are created
using different datums will show the same latitude/longitude in slightly
different locations.
All datums are named. The GPS system is based on the WGS-84 da-
tum, which covers the entire world. Other datums may also cover the
entire world or just a small portion of it. By default, your position is
based on the WGS-84 datum. The iFINDER, however, can show your
position using one of 191 different datums.
Different datums can only be selected in Advanced Mode. (To switch
from Easy to Advanced press
MENU| to ADVANCED MODE|ENT. A mes-
sage will appear asking you if you are sure you want to enter Advanced
Mode. Select
YES and press ENT.
To change the datum:
1. Press
MENU|MENU| to GPS SETUP|ENT| to DATUM SELECTION|ENT.
2. Scroll or to select the desired datum, then press
ENT.
3. Press
EXIT repeatedly to return to the main display.
A list of datums you can use with this unit is in the back of this man-
ual.