Chapter 3: Operating Instructions
29
and is shown as a straight line. Echoes from objects directly above the
bottom are indicated on the display.
A-Scope
The Soft Key for the A-Scope feature appears on the main Downlooker
display. The A-Scope feature presents a “real time” display of the area
under the boat.
Power
This button controls the power supply to the unit.
Gain/sensitivity
The “Gain” or “Sensitivity” setting controls the ability of the unit to tell the
difference between echoes of different strengths.
Display
The Display button allows you to step between the main displays or
“pages” presented by the unit.
VRM
“VRM” means “Variable Range Marker.” This is a way of finding the
depth of an object on the display. Using the VRM button, you can create
a line on the display, and move it up or down to match the depth of the
object you are checking.
Mark
The Mark button allows you to set a vertical marker on the display over a
selected point on the bottom. As the display scrolls past, the vertical line
keeps the same relative position.
Multi-purpose
This button allows you to adjust the contrast and backlighting level used
for the display.
Range
The “Range” changes the depth scale which can be displayed on the
screen.