Humminbird MEGA Live, Manual

Page: 71 / 75

65 Troubleshooting
Finding the Cause of Noise
Electrical noise usually affects the display with streaks or repetitive patterns on the
view. One or more of the following sources can cause noise or interference:
Possible Source of Noise Isolation
Other electronic devices Turn off any nearby electronic devices to see if
the problem goes away, then turn them on one
at a time to see if the noise re-appears.
Other sonar devices Turn off any nearby sonar devices to see if the
problem goes away, then turn them on one at a
time to see if the noise re-appears.
The boat’s engine To determine whether the boat’s engine is the
source of the noise, increase the RPMs while
the boat is in neutral and stationary to see if the
noise increases proportionately; if noise appears
when you rev the engine, the problem could
be the spark plugs, alternator, or tachometer
wiring. Replace the spark plugs with resistor
plugs, install an alternator filter, or route the
control head power and transducer cables away
from the engine wiring.