Context
The Range setting defines how "deep" you wish the ME70 to detect echoes. In other words, this is the vertical distance between the "top" and the "bottom" of the echogram. The Range setting specifies the "bottom" depth, while the Start Range setting specifies the "top" depth.
The range you specify applies to the currently selected echogram. It is identified with a thick border.Several echogram types are available.
In a Surface echogram, the Start Range value is used to determine from which depth the echogram will start. This is normally a few metres below the sea surface. The Range value is then used to define the vertical extension of the echogram.
ExampleStart Range in a surface-related echogram
In a surface echogram, set the Start Range value to 0 metres. This will make the echogram start from the sea surface (provided that the transducer offset has been defined).
Set Range to the current depth plus 20 metres. The echogram will now show the area from the sea surface and down to 20 metres "below"
the sea bottom. The sea bottom contour is easily detected when the depth changes.