Calibration Menu - Furuno FCV-2100 Operator's Manual

4.7.5

Calibration menu

You can calibrate (offset) the speed of sound, water temperature and other informa-
tion from [Calibrate] section of the [System] menu.
Menu item
[Sound Speed]
[Temperature]
[Bottom Level]
[Position to Start Bottom
Detection]
[Zero Line Rejector]
[Zero Line Area]
[Zero Line Fill]
[Draft]
[Gain ADJ]
[Fish Size]
[Calibration Setting]
Soun Sound Soun Soun S oun S S d er der der der der
Di Displ Disp l ay lay
Sound Speed
Measurement
Temperature
Alarm
Bottom Level
External Echo Sounder
Position to Start Bottom Detection
Sounder
HF
Zero Line Rejection
LF
Zero Line Area
Calibration
Zero Line Fill
TX/RX
Draft
System
Gain ADJ
Range
Fish Size
TX/RX
Calibration Setting
Control Unit
User Interface Settings
Calibration
Stabilization
M d Mode Mode
T Test Tests Test Test Test t s s s s
S S i
Adjust the sound velocity of the TX/RX signal if the depth indication is
incorrect, often caused by water temperature or salinity.
If the water temperature indication is wrong, you can correct it here.
For example, if the actual temperature is 2°C higher than the tempera-
ture displayed on screen, set the offset to [+2°C].
In the default bottom level setting [0], the equipment judges consecu-
tive strong echoes to be bottom echoes. If, in that setting, the depth
indication is unstable, adjust the bottom level. If vertical lines extend
upward from the bottom echo in the bottom lock display, lower the bot-
tom level to erase the vertical lines. If the level is too low, however, it
may be difficult to distinguish bottom fish from the bottom echo.
Set the depth threshold at which the seabed is detected.
Turn the zero line (transmission line) on or off. When turned on, the
transmission line disappears, which allows you to see fish echoes
near the surface clearly. The length of the transmission line changes
with transducer used and installation characteristics.
This function adjusts the transmission line so that the transmission line
disappears when the menu item [Zero Line Rejection] is turned on. For
a long tail, increase the value. If the transmission line does not disap-
pear, lower the TX power.
Turn off to see fish echoes within 1 m from the surface.
The default depth display shows the distance from the transducer. If
you would rather show the distance from the sea surface, set your
ship's draft. The draft line for HF and LF can be set respectively.
If the gain is too high or too low, or the gain for the low and high fre-
quencies appears unbalanced, you can compensate it here.
Compensate for incorrect fish size indications. A positive value in-
creases compensation, a negative value decreases compensation.
For example [+50] increases the size indication by 1.5 times.
Set the target strength (echo strength for individual fish). If a calibra-
tion sphere was used, its value is shown. This value may be fine tuned.
For further details, see section 2.2.8.
The larger the calibration figure the longer the length of the individual
fish, even if the received signal is the same strength.
4. ADVANCED SETTINGS
Cal Cal Cal Cal Calib C l C l ibr ibr ibr ibr ibr ib ati ati ati ation ati ti ti on on on on
1500.0
0.0
0
0.0
Off
4.5
Off
0.0
0
0
0.0
Description
4-13