531528-1_A - 757c_787c2_&_787c2i_Man_Eng.qxp 10/16/2006 10:44 AM

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Finding the Cause of Noise

Electrical noise usually affects the display with many black dots at high speeds, and high sensitivity readings. 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.

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.

Cavitation from the boat’s

Turbulence created by the propeller can cause

propeller

noise; make sure the transducer is mounted at

 

least 15” (38 cm) from the propeller, and that

 

the water flows smoothly over the face of the

 

transducer at all times.

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Humminbird 757c, 787c2i manual Finding the Cause of Noise
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757c, 787c2i specifications

The Humminbird 787c2i and 757c are advanced fish finders designed to enhance the fishing experience through their superior technology and features. These models are part of Humminbird's commitment to providing anglers with the tools needed to improve their catch rates and navigate the waters with ease.

One of the standout features of the Humminbird 787c2i is its brilliant 7-inch color display. The large, high-resolution screen offers crystal-clear imaging, making it easier to identify fish and underwater structures. Coupled with a user-friendly interface, the display allows anglers to quickly access vital information without distraction.

The 757c, while slightly smaller with a 7-inch screen as well, boasts similar color resolution and quality. Both models utilize Humminbird's cutting-edge sonar technologies, including DualBeam PLUS sonar, which provides versatility in fishing techniques. The DualBeam technology allows the user to switch between narrow and wide beams for precise coverage of underwater areas.

Another notable feature is the exclusive SwitchFire technology. This enables users to customize the way sonar returns are displayed on their screen. Anglers can choose between a traditional view or an enhanced view, allowing for a more detailed look at the underwater environment. The added water column data helps in recognizing fish movement and behavior, invaluable information for any angler.

Both models come equipped with built-in GPS capabilities. The 787c2i includes a mapping feature that allows for precise navigation on water. The included Navionics Gold cartography provides detailed charts and information about various water bodies, helping anglers to find new fishing hotspots effortlessly.

For connectivity, the Humminbird 787c2i and 757c support an array of accessories, including radar and i-Pilot Link, enhancing the user experience with added functionalities like autopilot and advanced navigation features.

Other characteristics include an accurate temperature sensor, adjustable backlighting for optimal visibility in various lighting conditions, and a flexible mounting system. Overall, the Humminbird 787c2i and 757c stand out not just for their features, but also for their reliability and performance on the water, making them a valuable choice for both novice and seasoned anglers. These fish finders embody the spirit of innovation that Humminbird is known for, ensuring that users have the best tools at their disposal for a successful fishing expedition.
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