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To adjust sensitivity in manual mode:
1. First, turn off Auto Sensitivity: from the Sonar Page, press
MENU|↓
to
AUTO SENSITIVITY|ENT.
2. Press ↑ to
SENSITIVITY|ENT and the Sensitivity Control Bar appears.
Press ↓ or ↑ to pick a different sensitivity setting. When it's set at the
desired level, press
EXIT.
To turn Auto Sensitivity back on:
From the Sonar Page, press
MENU|↓ to AUTO SENSITIVITY|ENT|EXIT.
NOTE:
To return to the original factory setting for Auto Sensitivity, see the
entry in this section on Reset Options. If sensitivity is in manual
mode, the Reset Options command will switch back to Auto and re-
set the factory setting at the same time.
Tip:
For quicker sensitivity adjustments, try leaving the Sensitivity
Control Bar on the screen as the chart scrolls. You can see the
changes on the screen as you press the up or down arrows. This is
handy when there's a lot of clutter in the water, and you are
matching the sensitivity to rapidly changing water conditions.
Set Keel Offset
This unit measures water depth from the face of the transducer. Since
the transducer is installed below the water surface, the distance dis-
played by the digital depth, chart depth scale, chart cursor or fish sym-
bols is not the exact water depth. If the transducer is 1 foot below the
surface, and the screen shows the water depth as 30 feet, then the ac-
tual depth is 31 feet.
On sailboats or other large vessels with deep drafts, the distance be-
tween the transducer installation and the keel or lower engine unit can
be several feet. In those cases, an inexact depth reading could result in
grounding or striking underwater structure. The Keel Offset feature
eliminates the need for the navigator to mentally calculate how much
water is under his keel.
Keel Offset lets you calibrate the digital depth: chart depth scale, chart
cursor depth and fish symbol depth displayed on the screen. To calibrate
the depth indicators, first measure the distance from the face of the trans-
ducer to the lowest part of the boat. In this example, we will use 3.5 feet.
We enter this as a negative 3.5 feet, which makes the depth indicators per-
form as if the transducer's lower in the water than it really is.
