Adjusting the Zoom Scale on the Radar Screen
The radar zoom scale, also called the radar signal range, represents the distance from your position (the center) to the outermost ring.
From a Radar screen, select 
or 
.
or .
Each ring represents an even division of the zoom scale.
For example, if the zoom scale is set at 3 miles, each ring represents 1 mile from the center out.