Temperature Graph
Some of the screens have a temperature graph, as shown
at right. Normally, the temperature graph has a 2° range.
On the screen shown at right, the temperature graph has
a range from 71° to 73°. You can change this range to 4°
or 10° using the "Temp Graph Scale" label on the Units of
Measure menu. Highlight that label, then press the right
arrow key until the desired temperature graph range is
highlighted. Press the EXIT key to erase the menu.
Reset Distance Log
If you have a speed sensor attached, the unit starts counting the distance
you've travelled each time you turn it on. You can reset this distance to zero
by turning the unit off and on again, however, it's easier to highlight the
"Reset Distance Log" label on the System Setup menu, then press the right
arrow key. This resets the log and keeps you in the System Setup menu.
To erase this menu, press the EXIT key.
Preset Options
The unit "remembers" all settings such as units of measure, auto/manual,
sensitivity, even when power is removed from the unit. To return the unit
to the factory settings, highlight the "Preset Options" label on the "System
Setup" menu, then press the right arrow key. It returns to the full chart
screen with all settings returned to their factory values.
Keel Offset
The sonar measures water depth from the face of the transducer. Since the
transducer is below the surface of the water, this distance is not the exact
water depth. If the transducer is one foot below the surface, and the sonar
reports the water depth as 30 feet, then the depth is actually 31 feet.
You can calibrate the depth reading using
the keel offset feature. First, highlight the
"Keel Offset" label on the "System Setup"
menu, then press the right arrow key. The
screen shown at right appears. The current
bottom depth shows in the upper left corner
of the screen. The keel offset shows in the
upper right corner. In this example, we need
to change the keel offset so that the sonar
will add one foot to the depth, since the
transducer is one foot below the surface.