detection, therefore, only the area around where the energy from the actual bottom returns are will
be searched to derive a bottom detection. Although the user enters a depth for the gate setting, to
the Sonic 2024/2022 this is a time to start searching and a time to stop searching.
Figure 94: Graphical representation of depth gate
The above representation illustrates how the depth gate narrows down the bottom detection search
area (in time) to only the area where the true bottom is expected. If the Maximum Depth gate was
not in this location, the second return could be strong enough so as to influence the bottom
detection process.
Again, it must be borne in mind that if the depth gate is set such that true bottom detections are
‘gated out’; those data are lost entirely and cannot be recovered.
5.14 Ruler
The ruler or measuring tool can be used to obtain range and bearing information, within the GUI, by
using the mouse cursor. Use Ctrl + Left Mouse Button (LMB), the cursor will change to a cross and
can be dragged to the target (once the range and bearing is initiated, the Ctrl button can be
released. The Range and Bearing information is along the bottom of the Sonic Control window. To
remove, the Ruler use Ctrl + Double Click LMB.
Figure 95: Ruler Function
Page 83 of 210
Version 5.0 Rev r002
Date 05-08-2014