Furuno NAVNET GD-1920C - Manual (Page 31)

2. RADAR OPERATION
2-2
2.3 Tuning
The radar receiver can be tuned automatically or manually, and the default tuning method is
automatic. If you require manual tuning, do the following:
1. Press the
MENU key to display the main menu.
2. Press the RADAR DISPLAY SETUP soft key.
3. Select TUNING, then press the EDIT soft key.
AUTO
MAN
TUNING
Tuning bar
Tuning window
4. Choose MAN.
5. Adjust the
ENTER knob until the tuning bar is at its longest position.
6. Press the MENU key to close the menu.
Note: If the auto setting does not provide satisfactory tuning, ask your dealer how to
re-adjust tuning.
2.4 Adjusting the Gain
The GAIN key adjusts the gain sensitivity of the radar receiver. It works in a manner similar
to that of volume control of a broadcast receiver, which amplifies received signals.
The proper setting is such that the background noise is just visible on the screen. If your
gain setting is too low, weak echoes may be missed. On the other hand, excessive gain
yields too much background noise; strong targets may be missed because of the poor
contrast between desired echoes and the background noise on the display.
To adjust the receiver sensitivity, transmit on long range, and then do the following:
1. Press the
GAIN key to show the “gain adjustment”
soft keys, and the last-used adjustment window
appears. The example below shows the gain
sensitivity adjustment window. The gain soft keys
shown depend on radar source as shown below.
2. If the gain sensitivity window is not displayed, press
the GAIN soft key to show the gain sensitivity setting
window.
3. Use the Trackball to select AUTO ROUGH, AUTO
MODERATE, AUTO CALM, or MAN (manual) as
appropriate. Select an AUTO option according to the sea state.
4. For manual adjustment, rotate the ENTER knob to adjust, while observing the radar
echo. The range of adjustment is 0-100.
5. Press the GAIN key on the front panel or the RETURN soft key to finish.
GAIN SENSITIVITY
AUTO ROUGH
AUTO MODERATE
AUTO CALM
MAN 0
Gain sensitivity window