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Whiteline
The Fishfinder 160C can help you to determine if the bottom is hard or soft. When the sonar sound waves are reflected back by the bottom, a hard bottom returns a stronger signal than a soft bottom. A thin whiteline indicates a softer bottom while a thick whiteline indicates a harder bottom. Normally, a red line shows the point where water meets the bottom. This line follows the bottom contour, along with any significant objects lying on the bottom. The unit uses the whiteline function to make the bottom layer information easier to distinguish.
With the Fishfinder 160C, active whiteline helps accentuate where strong signals are located, which makes bottom type determination easier. The example below shows the bottom return with and without the whiteline activated.
GETTING STARTED > UNDERSTANDING THE FISHFINDER AND SONAR
Thermoclines
Garmin’s
A rough definition of a thermocline is a break in water where the water temperature changes faster than the water above it.
Thermocline
Whiteline Hard Bottom Soft Bottom | Whiteline Turned Off |
Fishfinder 160C Owner’s Manual | 3 |