Range - Lowrance GlobalMap 2000 Installation And Operation Instructions Manual

currently in use. Continue
pressing the arrow keys until
you reach the desired level. If
the unit is in the automatic mode,
the sensitivity level can't be in-
creased or decreased past a
certain point.
An easy way to adjust the sen-
sitivity in the manual mode is to
first change the range to a depth
that's at least twice as deep as
the current range. For example,
if the range is 0 - 60 feet, change it to 0 - 120 feet. Now increase the
sensitivity by pressing the up arrow key until a second bottom signal
appears on the screen at twice the depth of the actual depth. This signal
is the "second echo" and is caused by the sound wave travelling from the
transducer, striking the bottom, reflecting off the water's surface, and
repeating the cycle. Once you see the second echo appear, change the
range back to the original scale. The sensitivity level should be close to
ideal. If there's too much noise on the screen (random echoes), or if you
still can't see enough detail, bump the sensitivity up or down a step.
Another way to adjust the sen-
sitivity level is through the
menus. Press the MENU key,
then press the key adjacent to
the "Sonar Controls ..." menu.
A screen similar to the one at
right appears. Now press the
right or left arrow keys to in-
crease or decrease the sensi-
tivity level. The bar graph in the
upper left corner of the screen
shows the level currently in use.
When you're finished with the adjustment, press the CLR key to erase the
menus.

RANGE

The range can only be varied a little when the automatic mode is on. The
unit adjusts the range to keep the bottom signal in the lower half of the
display at all times. You can change the range to virtually any number
between 5 and 5000 feet when the unit is in the manual mode.
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