GlossarySonar Terms:

Alarm, Depth: Depth Alarm is a user- controllable, au dible aler t that s ounds when depth is less than or equal to the setting.

Alarm, Temperature: Temperature Alarm is a user-co ntrollable, a udible aler t that sounds when the water surface temperature equals the setting.

Backlight: Backlight is a user-controllable illumination for the LCD for night and low light use.

Beam (S onar B eam): A sonar beam is th e wid e, cone-sha ped projection of sound waves formed as sound travels underwater. See Cone Angle.

Big Digits View: Big Digits View is a Humminbird® feature that displays the sonar graph and enlarged digital readouts for easy reading from a dis tance. This is a great tool when monitoring the digital depth is important - such as with higher boat speeds, or when vi ewing the uni t from a d istance. When speed input is available, the Big Digits View also shows the TripLog. See TripLog.

Bottom Black: Bottom Black is a Humminbird® feature that “fills in“ the area of the dis play below t he bottom cont our. Bottom Black is p referred by some anglers because of its high contrast and easy read ability, even though it c an obscure bottom hardness information.

Bottom Contour: Bottom Contour is t he profile of the bo ttom graphed to the display as the depth changes.

Bottom Hardn ess: Bottom Hardness is t he density (o r co mposition) of the bottom, which can often be determined by interpreting the main sonar return. Varying levels of hardness can be determined by interpreting the “thickness“ of the sonar return. Hard returns appear t hin a nd black, so fter retur ns a ppear thicker and less black. It is important to note that a sonar return from a sloping bottom can have the appearance of a softer bottom.

Cavitation: Cavitation is the effect of air b ubbles created as the pr opeller rotates and the boat moves through the water.

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Glossary