The Trolling Angles Calibration screen has several parts. It may be scrolled vertically to focus on the top or bottom sections. It may be tabbed or swiped horizontally to switch between the interactive graphical Trolling panel or the Edit panel.

Graph Section

The Graph section shows the profile of the trolling line with a true 1:1 aspect ratio.
The graph of the full line profile (gray) is updated whenever a measurement is added, deleted, or changed.
The graph of the submerged line (red), unsubmerged line (magenta), and water surface (blue) is updated whenever the desired trolling depth is changed.

Depth Control Section

The Depth Control lets you determine the line length required to reach your desired trolling depth.
Set the Height field to the trolling height of the rod tip above the water surface.
As you move the slider, the Depth Control shows the Line Length, the Line Angle at the surface, and the Depth.
The lengths of submerged and unsubmerged line are shown beneath the total line length.

GPS Section

Turn on the GPS switch to use the device’s GPS sensors to determine the current boat speed.

Alternatively, read the boat speed from the boat’s marine electronics, the boat’s speedometer, or other means.

Angle Measurements Section

The Measurements section shows the line angle measurements that make up the Trolling Angles calibration.

All angles of a calibration must be measured with the same speed and rod tip height.
Enter the Speed and Rod Tip Height that are in effect when measuring the line angles. You can use a different rod tip height while fishing.