Lowrance electronic LMS-334c iGPS GPS Receiver User Manual


 
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ring diameters are based on the current zoom range. For example: at the
100 mile zoom, the screen will show two rings with your current position
in the center. The large ring touching the left and right sides of the
screen is 100 miles in diameter (same as the zoom range). The second
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: From the Map Data menu, press to
RANGE
RINGS. With the option highlighted, press ENT to turn it on (check) or
turn it off (uncheck).
To set Lat/Long Grid: From the Map Data menu, press to
LAT/LON GRID LINES. With the option highlighted, press ENT to turn it on
(check) or turn it off (uncheck). Press
EXIT|EXIT to return to the main
page display.
Map Datum Selection
Maps and charts are based on a survey of an area covered by the map
or chart. These surveys are called Datums. Maps using different da-
tums will show the same latitude/longitude in different locations. The
GPS system used in this unit is the WGS-84 datum, which covers the
entire world. Other datums may also cover the entire world or just a
small portion of it. It, however, can show your position using any of 191
datums To change the datum:
1. Press
MENU|MENU| to GPS SETUP|ENT| to DATUM SELECTION|ENT.
2. Select the desired datum and press
ENT.
3. To return to the main page display, press
EXIT repeatedly.
Datum options for this unit are listed in the back of this manual.