Furuno GD-1700C - Manual (Page 161)

4. VIDEO SOUNDER OPERATION
4-17
4.10.2 Advancement synchronized with ship’s speed
With speed data provided by a speed measuring device, picture advance speed
may be automatically synchronized with ship’s speed. As shown in the figure
below the horizontal scale of the display is not influenced with the speed
dependent picture advance mode active, thus it permits judgment of fish school
size and abundance at any speed.
FULL
SPEED
HALF
SPEED
Actual Movement
Same size
fish schools
Speed
Normal Mode
Speed-Dependent Picture Advance Mode
Fish school shrinks as speed
is increased; expanded
as speed is decreased.
Fish schools are shown
same size regardless
of ship’s speed.
How the speed-dependent picture advance mode works
Activating/deactivating the speed-dependent picture advance mode
1. Press the [MENU] key followed by the SOUNDER MENU soft key.
2. Select PRR LEVEL.
3. Press the EDIT soft key to open the setting window.
4. Use the cursor pad
to select SPD SENSING PRR.
5. Press the ENTER soft key.
6. Press the [MENU] key to close the menu.
Note:
Use the same speed data (SOG or STW) throughout the network for
smooth advancement of the sounder picture.