Interpreting The Display; How The Picture Is Painted; Port-Stbd Picture - Furuno CH-37BB Operator's Manual

3. VERTICAL FAN MODE
3.13

Interpreting the Display

3.13.1

How the picture is painted

The sounding beam is emitted and the information (target echoes) obtained by the
beam appears in the corresponding sector as it appears on the sonar mode. The dif-
ference is that the training is performed only in vertical direction. It forms a sounding
area of a half-circle (like a slice of watermelon) to observe a vertical section of under-
water conditions.
Mode
Vertical
fan mode
3.13.2

Port-stbd picture

You can see fish echoes at the center-right of the CRT. The bottom is displayed wider
as the distance from the ship's position increases. Therefore, it may be difficult to dis-
criminate bottom fish.
3-10
Sounding beam
Select the bearing of the sounding beam
by TRAIN control, the sounding sector
center by the TILT control and the display
area by the SECTOR control.
Bow
180˚
Sector center
Example for sector angle
60°
180° 180° 180°
0˚
Tilting angle
Own ship Own ship Own ship
PORT STBD
Fish school
Bottom
Screen display
0° 0° 0°
60° 60° 60°
Display
area