5 automatic sounder operation, 6 manual sounder operation – Furuno GP-1650WDF User Manual
Page 19
2. VIDEO SOUNDER OPERATION
 
 
2-5
2.5 Automatic
Sounder
Operation
Automatic sounder operation is useful when 
you are preoccupied with other tasks and do 
not have time to adjust the display. 
 
How the automatic sounder works
The automatic sounder function 
automatically selects the proper gain, range 
scale and clutter suppression level according 
to depth. It works as follows: 
•
Range changes automatically to display 
the bottom echo on the screen. 
•
The gain is automatically adjusted to 
display the bottom echo in reddish brown 
(default color arrangement). 
•
Clutter, which suppresses low level noise, 
is automatically adjusted. 
Two types of automatic sounder 
modes 
Two types of automatic sounder modes are 
available: CRUISING and FISHING. 
CRUISING is for tracking the bottom, and 
FISHING is for searching fish schools. 
CRUISING uses a higher clutter rejection 
setting than FISHING therefore it is not 
recommended for fish detection - weak fish 
echoes may be erased by the clutter 
suppression circuit. 
 
How to enable automatic sounder 
operation 
1. To show the mode/freq window: 
 
Normal sounder display:
Press the
MODE/FREQ soft key.
Plotter/sounder display:
Press the
SNDR, MODE/FREQ soft keys in order.
Dual-frequency display:
Press the
MODE soft key.
MODE/FREQ
▲
AUTO CRUISING
AUTO FISHING
MANUAL
▼
Mode/frequency window
 
2. Press ▲ or ▼ to select AUTO CRUISING 
or AUTO FISHING.
3. Press the RETURN soft key to close the
window, or wait 10 seconds and the 
window closes automatically. 
2.6 Manual
Sounder
Operation
Manual operation is useful for observing fish 
schools and bottom using a fixed gain 
setting. 
 
The gain, clutter, range and range shifting 
functions used together give you the means 
to select the depth you can see on screen. 
The basic range can be thought of as 
providing a “window” into the water column 
and range shifting as moving the “window” to 
the desired depth. 
 
Selecting the manual mode
1. Press the appropriate soft keys to show
the MODE/FREQ window.
2. Select MANUAL. 
3. Press the RETURN soft key.