Furuno 1834C-BB, GD-1920C-BB Erasing the Heading Line, North Marker, Reducing Noise Interference

2. RADAR OPERATION

2.12 Erasing the Heading Line, North Marker

The heading line indicates the ship's heading in all presentation modes. It is a line from the own ship position to the outer edge of the radar display area and appears at zero degrees on the bearing scale in head-up mode; it changes its orientation in the north-up, course-up and true motion modes with ship’s movement.

The north marker appears as a short dashed line. In the head-up and course-up modes the north marker moves around the bearing scale as the ship’s heading moves.

To temporarily erase the heading line and north marker, press the B: RADAR DISPLY soft

key followed by the D: HL OFF soft key. Release the key to redisplay the markers. (If the radar soft keys are not shown, hit the CLEAR key to display them.)

2.13 Reducing Noise Interference

Noise, appearing on the displays as random “speckles,” can be reduced as follows:

1.Press the MENU key to open the menu.

2.Press the A: RADAR DISPLAY SETUP soft key.

3.Select NOISE REJECTION, then press the A: EDIT soft key.

4.Select OFF, LOW or HIGH as appropriate.

5.Press the C: ENTER soft key.

6.Press the MENU key to close the menu.

2.14 Rejecting Radar Interference

Radar interference may occur when near another shipborne radar that is operating in the same frequency band as your radar. Its on-screen appearance looks like many bright dots either scattered at random or in the form of dotted lines extending from the center to the edge of the display. Interference effects are distinguishable from normal echoes because they do not appear in the same place on successive rotations of the scanner.

Be sure to turn off the interference rejector when no interference exists – weak targets may be missed.

Radar interference

2-11