advertisement
Chapter 10 - Understanding Radar Functions
Understanding how radar works
The word “radar” is an acronym for “Radio Detecting and
Ranging.” A radio transmitter sends out a very short microwave pulse, and then a receiver listens for that signal’s echo when it’s bounced back from something in its path
(called the “target”). The returning signal is processed by a computer to determine its relative distance, position, and bearing. This information is graphically displayed on a screen for you to see. The target might be other boats or ships, navigational markers, flocks of birds, land masses, or some other object. By knowing how long it takes for a signal to return, the distance to a target can be determined. As the radar antenna scans through a 360-degree rotation, it shows where the target is relative to your position. By repeated scans of a target such as another vessel, you can see where that other vessel is moving. For more information about how radar works, see ”Introducing radar” starting on page 187.
Displaying and controlling radar
To display radar alone on a full screen:
1. Press the CHART key to display the CHART screen.
Page 126 958 Operator’s Manual, Rev. A
Chapter 10 - Understanding Radar Functions
2. Press the SPLIT key to display the SELECT A SPLIT
SCREEN menu.
3. Press the RADAR key to view the radar:
958 Operator’s Manual, Rev. A
NOTE:
If you haven’t turned the radar transmitter on, you’ll see a blank screen or a residual echo. To turn on the radar transmitter, see ”Turning radar on and off” starting on page 128.
Among other items of information, the radar image includes:
• A north indicator to show the direction of True or
Magnetic North (see ”Choosing magnetic variation” starting on page 169)
Page 127
advertisement