Lowrance LMS-320, Руководство по эксплуатации

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NOTE:
If knowing the exact depth of water beneath the keel is less impor-
tant, you can calibrate the depth indicators so that they show the ac-
tual water depth from surface to bottom. To do this, first measure the
distance from the face of the transducer up to the surface (the water
line on the boat). In this example, we will use 1.5 feet. This will be en-
tered as a
positive 1.5 feet, which makes the depth indicators perform
as if the transducer's higher in the water than it really is.
1. Press
MENU
|
MENU
|
↓
to
S
ET
K
EEL
O
FFSET
|
ENT
.
2. The Keel Offset dialog box appears with a plus (+) sign at the
front of the box.
3. Press
→
to the first number, then press
↑
to change the number
to 1.
4. Press
→
to the second number, them press
↑
to change the num-
ber to 5, then press
EXIT
. The depth indicators now accurately show
the water depth from surface to bottom.
Sensitivity & Auto Sensitivity
The sensitivity controls the ability of the unit to pick up echoes. Sensi-
tivity can be adjusted, because water conditions vary greatly. A low
sensitivity level (from zero to 50 percent) excludes much of the bottom
information, fish signals, and other target information.
High sensitivity levels let you see this detail, but it can also clutter the
screen with many undesired signals. Typically, the best sensitivity level
shows a good solid bottom signal with Grayline and some surface clutter.
Automatic Sensitivity
The default sensitivity mode is automatic. The unit bases the sensitiv-
ity level on water depth and conditions. When the unit is in the auto-
matic mode, sensitivity is automatically adjusted to keep a solid bottom
signal displayed, plus a little more power. This gives it the capability to
show fish and other detail.
However, situations occur when it becomes necessary to increase or de-
crease the sensitivity. This typically happens when you wish to see
more detail, so an increase in sensitivity is indicated. Or, wave action
and boat wakes can create enough tiny air bubbles to clutter much of
the water column. In that case, a decrease in sensitivity is indicated to
reduce some of the clutter.
The control bar used to adjust sensitivity up or down is the same
whether the unit is in the automatic or manual mode. In automatic you