Sonar Noise Rejection Settings
From a sonar view, select Menu > Sonar Setup > Noise Reject.
Interference: Adjusts the sensitivity to reduce the effects of interference from nearby sources of noise.
The lowest interference setting that achieves the desired improvement should be used to remove
interference from the screen. Correcting installation issues that cause noise is the best way to eliminate
interference.
Color Limit: Hides part of the color palette to help eliminate fields of weak clutter.
By setting the color limit to the color of the undesired returns, you can eliminate the display of undesired
returns on the screen.
Smoothing: Removes noise that is not part of a normal sonar return, and adjusts the appearance of returns,
such as the bottom.
When smoothing is set to high, more of the low-level noise remains than when using the interference control,
but the noise is more subdued because of averaging. Smoothing can remove speckle from the bottom.
Smoothing and interference work well together to eliminate low-level noise. You can adjust the interference
and smoothing settings incrementally to remove undesirable noise from the display.
Surface Noise: Hides surface noise to help reduce clutter. Wider beam widths (lower frequencies) can show
more targets, but can generate more surface noise.
TVG: Adjusts the time varying gain, which can reduce noise.
This control is best used for situations when you want to control and suppress clutter or noise near the
water surface. It also allows for the display of targets near the surface that are otherwise hidden or masked
by surface noise.
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Sonar Fishfinder