Lowrance 540c baja Guida Al Funzionamento

87 

To turn on/off Lat/Long Grid lines: 
1. From the Map Page, press 

|

↓ to 

|

.  

2. Press 

↓, to 

. With the option highlighted, press 

 

to check it (turn on) and uncheck it (turn off.)  
3. After the option is set, press 

|

 to return to the page display. 

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. 
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 unit uses the 

WGS-84 datum. It, however, can show your position using any of 191 

datums. Different datums can be selected. To change the datum: 
1. Press 

|

|

↓ to 

|

|

↓ to 

|

. 

2. Use 

↓ ↑ 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 turn on or off any of these items to customize the map.