Garmin GMR 21 - Manual (Page 20)

16 GMR 21/41 Owner’s Manual
GMR 21/41 O
PERATION
> T
HE
R
ADAR
A
DJUSTMENT
M
ENU
Rings—is used to turn the radar Range Rings On or Off.
Background—is used to select a background color for the Radar
Page. The options are Black, Blue, and White.
Heading Line—is used to turn the Heading Line On or Off.
Bearing Reference—has two settings, Absolute and Relative.
Relative calculates the bearing relative to own vessel heading.
Absolute calculates the bearing referring to North.
Navigation Features—there are three selectable Navigation
Features: Waypoints, Bearing Line, and Course Line. When selected,
that feature is displayed on the Radar Page.
• Waypoints—displays user waypoints on the Radar Page.
• Bearing Line—displays a bearing line on the Radar Page.
The bearing line is displayed as a line from your current
position to the active destination waypoint, similar to a
traditional lollipop.
• Course Line—displays a course line from your starting point
to the active destination waypoint, similar to navigation on a
map.
The MARPA Tab
See “MARPA Setup” on page 12.
The Advanced Tab
AFC Mode—has two settings, Auto and Manual. In Auto mode the
scanner frequency is automatically adjusted for optimal performance
and is recommended.
The Advanced Tab