The sound pulses are transmitted at various frequencies depending on the application. Very high frequencies (455 kHz) are used for greatest definition but the operating depth is limited. High frequencies (200 kHz) are commonly used on consumer sonar and provide a good balance between depth performance and resolution. Low frequencies (83 kHz) are typically used to achieve greater depth capability.

The power output is the amount of energy generated by the sonar transmitter. It is commonly measured using two methods:

Root Mean Square (RMS) measures power output over the entire transmit cycle.

Peak to Peak measures power output at the highest points.

The benefits of increased power output are the ability to detect smaller targets at greater distances, ability to overcome noise, better high speed performance and enhanced depth capability.

3D Sonar

Your 900 Series™ Fishing System uses a six-element transducer that transmits at 455 kHz and is capable of reaching depths of 240 ft (75 m).

Each transmitted beam is 16 degrees in width and is symmetrical. The six beams are lined up next to each other to provide a total coverage of 53 degrees from side to side, and 16 degrees from front to back. Using multiple narrow beams together

gives you a wide area of coverage for terrain interpretation and fish location, without sacrificing the detail only a narrow beam can provide. Your 900 Series™ Fishing System gathers information from a continuous series of these returned signals. It then interprets this information to create a detailed 3-dimensional view of the terrain passing beneath your boat as you travel across the water.

2D Sonar

Your 900 Series™ Fishing System also has the capability of displaying traditional 2-dimensional sonar information from either a 455 kHz beam or an 83 kHz beam. The 455 kHz single beam has the advantage of providing increased sonar resolution but is limited to a depth capability of 240 ft (75 m). The 83 kHz single beam sonar has the advantage of providing sonar information to 1000 ft (330 m) but the sonar resolution is not as great as with the 455 kHz single beam.

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Humminbird 967C manual 3D Sonar, 2D Sonar, Peak to Peak measures power output at the highest points