Furuno FSV-84 SONAR User Manual


 
4. SLANT MODE
4-26
4.13 Detecting Fish Schools Aurally
Sometimes you may be preoccupied with other tasks and unable to concentrate
on watching the sonar picture. In such cases it would be a good choice to use
the audio function. This function enables you to monitor echoes from fish
schools and seabed through the built-in speaker.
After you’ve become accustomed to monitoring fish aurally, you should be able
to detect a fish school from a range longer than you can detect it on the screen.
In addition you may judge whether the fish school is approaching or going away;
the tone becomes higher when the school is approaching and lowers when the
school is going away.
4.13.1 Selecting direction
In the default setting, the audio function is on and the audio sector is 30°.
1. Operate the trackball to place the trackball mark on the direction you want to
monitor through the speaker.
2. Press the [R/B AUDIO] key.
The audio bearing mark appears on the bearing selected, in a 30°, 60°, 90°,
180° or 330° sector centering the audio bearing mark. Echoes are monitored
through the speaker. You can adjust speaker volume with the [AUDIO] control.
Note: When the trackball mark is placed near own ship mark and the [R/B
AUDIO] key is pressed, the range mark and the related data at the bottom of the
screen are erased. Note that the audio bearing is erased when “AUDIO” on the
ALARM & AUDIO menu is turned off.
Range and audio bearing
marks data
Range mark
Audio bearing mark
R 400m
B 45°
A
Range and audio bearing marks