How to open
You open this function from the Active menu.
Description
This filter is useful if you try to find fish close to the bottom. Select a Target Threshold value to control the "strength" of the filter. A higher numerical value increases the filter efficiency and reduces the bottom echo accordingly.
Select the middle of the button to open a small menu with the available options. Select the left side of the button to select a "lower"' menu choice. Select the right side of the button to select a "higher"' menu choice.