Humminbird LCR 4x6 Operation Manual page 20

THINGS TO KNOW ABOUT AUTOMATIC AND MANUAL OPERATION
A. When the LCR is turned on the unit is in the automatic mode. This is indicated on the menu
and in the lower left area of the screen. In the Automatic Mode the sensitivity
Is continuously adjusted automatically, the correct depth range is automatically selected and the
area below the bottom return is blackened out making the bottom easy to see.
B. There are 16 levels of sensitivity adjustment, indicated by the bars on the menu and in the
lower left area of the display.
C. Pressing either the
D. In the Manual Mode the digital bottom reading goes off and the automatic range change is
off. Also the area below the bottom is no longer blacked out, therefore a second return or
double echo can be displayed if desired (see Figure 16). Also, the hardness of the bottom
can sometimes be determined by the thickness of the second bottom return. For example, a
hard or rock bottom will give a wider return as compared to a soft or muddy bottom.
, , or the button will put the LCR in the Manual Mode.