Furuno NAVNET TZ2 TZTL12F - How to Activate or Deactivate an Alarm; Alarm Sensitivity; Accu-Fish

7. FISH FINDER (SOUNDER)
7-15
7.13.2 How to activate or deactivate an alarm
Fish alarm
1. Open the home screen, then tap [Settings]→[Fish Finder].
2. Turn [Fish Alarm] on or off.
The fish alarm can also be activated or deactivated with [Fish Alarm] on the pop-up
menu.
Bottom lock fish alarm
1. Open the Home screen, then tap [Settings]→[Fish Finder].
2. Turn [Fish Alarm for Bottom Lock] on or off.
3. Tap the close button on the title bar to finish.
7.13.3 Alarm sensitivity
You can select the echo strength that releases the fish alarms.
1. Open the Home screen, then tap [Settings]→[Fish Finder].
2. Tap [Fish Alarm Level].
3. Tap which echo strength releases the fish and bottom lock alarms. Low releases
the alarm against weak-to-strong echoes.
4. Tap the close button on the title bar to finish.
7.14 ACCU-FISH
™
The ACCU-FISH
™
feature, which requires an ACCU-FISH
™
capable transducer or
Bottom Discrimination Sounder BBDS1 or Network Fish Finder DFF1-UHD, calculates
the length of each fish and shows a fish symbol and depth value or fish length.
Usage guidelines
• The information provided by this feature is intended for reference only. It does not in-
dicate the exact length of a fish.
• ACCU-FISH
™
is available for use on both the high and low frequencies.
• The intensity of an echo depends on fish species. If the indicated length is different
from the true length, you can apply an offset. See section 7.14.2.
• Two frequencies are transmitted alternately without reference to the current display
mode.
• Use this feature with ship speed of 10 knots or less and depth between 2 and 100 m.
• This feature cannot be used with the inside-hull transducer since a fish may not be
detected depending on the frequency of the transducer. Even if a fish is detected, the
fish length indicated may be smaller than the actual length.
• ACCU-FISH
™
uses both low and high frequency echoes for the measurements re-
gardless of the frequency mode in use.
• Echoes from a school of fish can be in more than one layer, which can cause wrong
length indication.
• The fish symbol indication is not shown when the bottom echo is not shown on the
screen.
• The split range feature is inoperative when ACCU-FISH
™
is on.