NorthStar EXPLORER 443S Installation And Operation Manual page 29

f) Check the transducer and power cable LT
connectors at the back of the display unit
are securely plugged in and the collar is
locked in place. The collar must be secure for
watertight connection.
g) Inspect the transducer and power cables
from end to end for damage such as cuts,
breaks or squashed sections.
h) Ensure there is not another fishfinder or
depth sounder turned on, which may
interfere with the Explorer 443s/443sp.
i) Electrical noise from the boat's engine or
an accessory may be interfering with the
transducer(s) and/or the Northstar fishfinder.
This may cause the fishfinder to automatically
decrease the gain unless using Manual Gain.
The fishfinder thus eliminates weaker signals
such as fish or even the bottom from the
display. This may be checked by switching
off other instruments, accessories (e.g. bilge
pump) and the motor until the offending
device is located. To stop problems from
electrical noise, try:
- Rerouting the power and transducer cable(s)
away from the boat's other electrical wiring.
- Routing the unit's power cable directly to the
battery instead of through a fuse block or
ignition switch.
4. Bottom is not displayed:
a) The fishfinder may have Manual Range
selected and the depth may be outside the
range value selected. Either change the
fishfinder to Auto Range or select another
depth range (see section 3-8).
b) The depth may be outside the fishfinder's
range. While in Auto Range, the display
unit will flash the last depth displayed, then
display "--.-" to indicate that there is no
bottom detected. A display of the bottom
should reappear when it is shallower than
180 m (600 ft).
Northstar Explorer 443s/443sp Installation and Operation Manual
5. The bottom is displayed too far up the
screen:
The fishfinder may have Manual Range
selected and the selected Range value is
too high for the depth. Either change the
fishfinder to Auto Range or select another
depth range (see section 3-8).
6. Bottom echo disappears or erratic digital
reading while the boat is moving:
a) Ensure the back of the bottom surface of the
transducer is slightly lower than the front and
the front is as deep in the water as possible in
order to minimise the generation of bubbles
through cavitation. See the Transducer
Installation Guide for more information.
b) The transducer may be in turbulent water.
Air bubbles in the water disrupt the echoes
returned, interfering with the fishfinder's
ability to find the bottom or other targets.
This often happens when the boat is
reversed. The transducer must be mounted
in a smooth flow of water in order for the
fishfinder to work at all boat speeds.
c) Electrical noise from the boat's motor
can interfere with the fishfinder. Try some
suppression spark plugs.
7. If the fishfinder beeps when turned on
but nothing is displayed:
The fishfinder may be operating, but the
contrast settings may have been set too
high or low. Power off the fishfinder. Then
hold and press
the default contrast setting.
8. The wrong language is displayed:
(See section 2).
to reset the fishfinder to
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