see if this works Muskrat...I was just never sure of the application and when to use it and for what
Adjusting the Zoom
You can adjust the zoom manually by specifying the span and a
fixed starting depth. For example, when the depth is 15 m and
the starting depth is 5 m, the device displays a magnified area
from 5 to 20 m deep.
You also can allow the device to adjust the zoom automatically
by specifying a span. The device calculates the zoom area from
the bottom of the water. For example, if you select a span of
10 m, the device displays an magnified area from the bottom of
the water to 10 m above the bottom.
1 From a sonar screen, select > Zoom.
2 Select an option:
• Select Bottom Lock to lock the screen to the water
bottom.
• Select Manual to manually set the zoom.
• Select Auto to automatically set the zoom.
• Select Split Zoom to turn on the split-zoom view.
Locking the Screen to the Water Bottom
You can lock the screen to the water bottom. For example, if you
select a span of 20 meters, the device shows an area from the
water bottom to 20 meters above the bottom. The span appears
on the right side.
1 From a sonar view, select > Zoom > Bottom Lock.
2 Select a span.
Setting the Bottom Search Limit
You can set a maximum depth at which the auto range feature
searches for the bottom. A lower limit acquires data about the
bottom faster than a higher limit.
1 From a sonar screen, select > Sonar Setup > Bottom
Search Limit.
2 Select a range.
Sonar Frequencies
NOTE: The frequencies that are available depend on the
transducer being used.
Adjusting the frequency helps adapt the sonar for your particular
goals and the present depth of the water.
Selecting Frequencies
NOTE: You cannot adjust the frequency for all sonar views and
transducers.
You can indicate which frequencies appear on the sonar screen.
1 From a sonar view, select > Frequency.
2 Select a frequency suited to your needs and water depth.
For more information on frequencies, see Sonar
Frequencies, page 4.
Creating a Frequency Preset
NOTE: Not available with all transducers.
You can create a preset to save a specific sonar frequency,
which allows you to change frequencies quickly.
1 From a sonar view, select > Frequency.
2 Select Add.
3 Enter a frequency.
Setting the Scroll Speed
You can set the rate at which the sonar image moves across the
screen. A higher scroll speed shows more detail, especially
while moving or trolling. A lower scroll speed displays sonar
information on the screen longer. Setting the scroll speed on
one sonar view applies to all the sonar views.
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