531617-1_A - 1197c_ManE.qxp 11/6/2007 4:40 AM Page 182

Glossary

Sonar Terms

SONAR: SONAR is the acronym for SOund and NAvigation Ranging. Sonar technology uses precision sound bursts transmitted underwater to determine the distance and other attributes of objects in the water. Distance can be determined because the speed of sound in water is constant, and the time for the signal to return is measured. Sound also travels very quickly underwater, making sonar a responsive, cost-effective tool. Sonar is the basic technology behind all recreational and commercial fishfinding and depthfinding devices.

Sonar Echo Enhancement: Sonar Echo Enhancement is a Humminbird® feature that describes the high degree of sonar sensitivity achieved through a combination of transmitter/receiver and software algorithms. The result of Sonar Echo Enhancement is to display virtually everything in the water that is of interest to the angler, including bait fish, game fish, thermoclines, weed beds, subtle structure, and more.

Sonar Update Rate: Sonar Update Rate is the number of times per second that the transmitter/receiver sends and receives sonar signals. A very fast sonar update rate collects more information and provides a more detailed image of the bottom, fish and structure. Many Humminbird® units operate at up to 40 times per second when in single frequency operation. Due to the limitation of the speed of sound in water, the update rate begins to slow as depth increases to deeper than 50 feet. In very shallow water (less than 10 feet), however, update rates as much as 60 times per second can be achieved.

Speed: Speed is the rate at which the boat moves through the water. Boat speed can be measured as Speed Over Ground or Speed Through Water. Speed Over Ground is provided by GPS, and is the measurement of the boats progress across a given distance. Speed Through Water is provided by a speed paddlewheel, and is the measurement of the flow past the boat, which may vary depending on current speed and direction. Speed Through Water is most critical for anglers using downriggers, as it impacts the running depth of the down riggers. Speed Over Ground is optimal for navigation, as accurate destination times can be derived from this measurement. Humminbird® products allow for input and display of both sources.

Structure: Structure is a general term for objects on the bottom that present a discontinuity and are a likely attractor for fish. This includes bottom contour features (drop-offs, humps, and holes), standing structure (stumps, timbers, brush piles) and a wide range of other potential objects (sunken boats, reefs). Humminbird® units excel at showing structure with great detail over a wider area due to unique sonar configurations developed for the angler.

Structure ID®: Structure ID® is a Humminbird® feature that describes the traditional grayscale method of presenting sonar information. See Grayscale.

Surface Clutter: Surface Clutter is a phenomenon where sonar returns are reflected off of tiny objects near the surface of the water, including algae and even air bubbles. Typically, saltwater environments have significantly greater surface clutter than freshwater due to continuous wind and wave action that causes aeration at the surface. The Surface Clutter menu provides manual control to bias the default settings under extreme conditions.

Target Separation: Target Separation is the measurement of minimum distance that a fishfinder needs to be able to recognize two very close objects as two distinct targets (i.e. two fish hanging very close, or a fish hanging very close to structure). Humminbird® fishfinders provide a very good 2 1/2 inches of target separation in shallower than 100 feet of depth. Target separation decreases as depth increases due to the need for longer Pulse Width to achieve greater depth. See Pulse Width.

Thermoclines: Thermoclines are water layer(s) of distinctly different temperatures that create a sonar reflection due to the density of the differing water temperatures. Typically a thermocline will appear as a continuous band across the display at some distance above the bottom contour. Thermoclines are of interest to anglers because fish will suspend above or below the thermocline as they seek the optimum temperature and oxygen levels.

Time Variable Gain: Time Variable Gain is a processing step applied to the sonar return to "normalize" the data so that objects of equal size (i.e. fish) appear to be the same size, even if they are separated by a good distance. Time Variable Gain is a fundamental attribute of good sonar, but is often promoted as a feature.

Total Screen Update®: A Humminbird® feature that refreshes and updates all the sonar information on the display when a range change occurs. Without Total Screen Update®, only the most recent sonar information would be drawn to the new range, and the old sonar information would continue to scroll off the screen at the old range.

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Humminbird 1197C SI warranty 182

1197C SI specifications

The Humminbird 1197C SI is a high-performance fishfinder that has made waves in the world of angling technology. This device seamlessly integrates cutting-edge sonar technology with an intuitive user interface, making it a favorite among both novice and professional anglers.

One of the standout features of the 1197C SI is its Side Imaging technology. This unique sonar function allows users to see what lies beneath the water's surface, providing a wide, detailed view of the underwater environment. It operates at a frequency of 455 kHz and 800 kHz, enabling exceptional clarity and detail, even at considerable depths. This feature is particularly beneficial for identifying underwater structures such as rocks, wrecks, and weed beds, which are often hotspots for fish.

Another innovative component of the 1197C SI is its DualBeam PLUS sonar. This technology provides both a narrow and a wide beam, giving users the versatility to search for fish over a broader area while also honing in on specific targets. The combination of Side Imaging and DualBeam sonar results in an impressive level of detail and accuracy in fish detection.

The 1197C SI also boasts a large 10.4-inch color display, providing crisp visuals and easy navigation through the various features. The screen is designed for easy reading in bright sunlight, ensuring that anglers can rely on it no matter the fishing conditions. Additionally, the unit supports a variety of view options, allowing users to select from different display modes to suit their preferences.

Integration with GPS is another key characteristic of the Humminbird 1197C SI. Built-in GPS capabilities allow anglers to mark waypoints, create routes, and access detailed maps and charts. This feature not only aids in navigation but also helps anglers return to successful fishing spots with ease.

The 1197C SI is also equipped with advanced networking capabilities, enabling it to connect with other devices, such as additional sonar units or autopilot systems. This increases the overall functionality and enhances the fishing experience by providing a more integrated system.

In conclusion, the Humminbird 1197C SI stands out for its advanced technologies such as Side Imaging, DualBeam sonar, and comprehensive GPS capabilities. With its large display and user-friendly interface, it has become an essential tool for anglers looking to increase their success on the water. With lasting durability and a wealth of features, the 1197C SI is a smart investment for serious fishing enthusiasts.