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this is often of interest to the user, it is primarily a diagnostic tool for the
repair technician should the unit need service.
Sonar Beams.
The second Diagnostic screen provides valuable information
about the sonar function of the 450TX. The three columns of information
show the raw sonar signal as it is seen by the unit.
This information is useful in both troubleshooting a potential fault, as well
as aiding in the transducer installation (for through the hull installations
only).
The sonar diagrams indicate the returned signal of each sonar pulse
transmission. By analyzing these diagrams, the user can gain additional
insight into the performance of the unit.
The diagrams show time delay (distance) on the vertical axis, and amplitude
or strength of return on the horizontal axis. An “amplitude” number shows
the relative strength of each return signal. The depth number shows the
depth of water beneath the boat as measured by each of the three beams.
With the boat stationary over a flat, consistent bottom, the sonar returns
from the left and right beams should be identical. Any discrepancy
between these signals may indicate a problem with the location of the
transducer. (Often voids or irregularities in the laminated hull of a fiberglass
boat will block or degrade one or more of the sonar signals.)
By referring to this screen prior to permanently mounting a through-the-
hull transducer, the location can be adjusted until no visible loss is
observed.
The diagram of the center beam cannot be compared to the left and right
beams as this beam is a different frequency and beam width. The diagram
is useful in ensuring that the center beam is present and of sufficient
strength.
The depth of the water beneath the boat is shown for each of the three
beams. In operation, only the center beam is used to display this depth,
however, the depth number is another means of comparison.
When in diagnostic, two menus are available to the user: Depth Range, and
ADVANCED FEATURES
USING DIAGNOSTIC
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