Lowrance electronic globalmap baja 840c Manual Do Utilizador

81 

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 cre-

ated 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 

shows using the WGS-84 datum. It, however, can show your position 

using one of 191 different datums. To change the datum: 
1. Press 

|

|

↓

 to 

|

|

↓

 to 

|

. 

2. Scroll 

↓

 or 

↑

 to select the desired datum, then press 

. 

3. To return to the last page displayed, press 

|

. 

A list of the datums used by this unit is in the back of this manual. 

 

 

This menu determines which of the mapping features are shown on the 

screen. This includes waypoints, trails, icons, cities, highways, etc. You 

can selectively turn on or off any of these items, customizing the map to 

your needs. 
To get to Map Categories:  

1. From the Map Page, press 

|

↓

 to 

|

. 

2. Press 

↑

 or 

↓

 to select a category or press 

→

 then press 

↑

 or 

↓

 to select 

a subcategory. Press 

 to turn it off (no check) or on (checked). 

3. To return to the last page displayed, press 

|

.