Furuno FR-8252 EN - Manual (Page 26)

1. OPERATIONAL OVERVIEW
1-12
1.10 Adjusting the Gain (sensitivity)
The gain functions to adjust the receiver sensitivity for the best reception of signals of widely
varying amplitudes.
1.10.1 Choosing gain adjustment method
Gain may be adjusted automatically or manually. Push the GAIN control to choose automatic or
manual adjustment alternately. The adjustment method currently chosen is show at the top right
corner of the screen. In the example below the gain adjustment method is “AUTO”.
Gain adjustment method indicator
1.10.2 Setting automatic gain level
1. Press the MENU key to open the menu.
2. Choose the Echo menu and press the ENTER key.
3. Choose Auto Gain and press the ENTER key.
4. Choose the option which best matches current sea condition and press the ENTER key.
5. Press the MENU key to close the menu. Gain is automatically adjusted according to the level
selected.
1.10.3 Manual gain adjustment
Adjust the gain such that noise faintly appears over the entire screen. If the gain is too low weak
echoes will not be displayed and if the gain is too high, weak echoes will be hidden in background
noise.
1. Push the GAIN control to show “GAIN MAN” as the gain adjustment method.
2. Rotate the GAIN control to adjust the gain. Adjust the control so background noise is just visible
on the screen.
TUNE AUTO
GAIN AUTO
SEA AUTO
RAIN AUTO
Gain adjustment method (AUTO)
Rough
Moderate
Calm