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•  Scale—controls the appearance of the depth scale shown 

vertically along the right side of the graph. You can configure 

the depth scale to appear in one of four different ways: as an 

Overlay, in the Corners, Basic, or No Scale.

•  Water Temperature Number and Water Speed Number—

hides or shows temperature and water speed on the Sonar 

Page. When set to Auto, the unit automatically shows this 

information, only if it is received from the transducer.

•  Color Scheme—sets the colors for the Sonar and Flasher 

Pages.

  NOTE: If the unit is unable to track the bottom for any reason, 

the digits in the depth window flash on and off to alert you that 

the unit is not tracking the bottom. 

 

The area covered by the transmitted sound waves is determined 

by the cone angle of the transducer and the water depth. The wide 

cone angles (40°) associated with low frequencies (50 kHz/80kHz) 

provide a large coverage area for finding fish within a coverage 

width that is approximately 2/3 of the water depth. However, this 

also means that wide cone angles produce less bottom detail and 

resolution. As shown in the drawing on 

, the 40° cone angle 

produces a coverage area of approximately a 20-foot diameter 

circle at a 30-foot depth. 
The narrow cone angles (10°) associated with the high frequencies 

(200 kHz) provide better bottom resolution and crisper detail, but 

cannot show a large coverage area for finding fish. The 10° cone 

angle provides a coverage width that is approximately 2/10 of the 

water depth. As shown in the drawing on the far right, the 10° cone 

angle produces a coverage area of approximately a 6-foot diameter 

circle at a 30-foot depth. 
Dual frequency or dual beam modes combine both frequencies to 

get the best coverage area and contour/depth readings.