96
95
Pixels, Vertical:
Vertical Pixels are a number of vertical picture elements in a single
column on an LCD display. A greater number of vertical pixels provide finer
resolution of targets detected by sonar. Essentially, a vertical distance (the depth),
when divided by a larger number, breaks that distance into smaller samples, each
representing a smaller area and thus providing more detail. In fishfinders, vertical
pixels are more critical than horizontal pixels because the horizontal axis of the
display represents time, or history. Sonar information on the horizontal axis can
vary greatly, depending on boat speed and the Chart Speed setting. A greater
number of horizontal pixels show more sonar history that the boat has passed
through. On many models, Humminbird® provides the most vertical pixels to
provide a better display resolution. See
Chart Speed
and
Pixels
.
Power Output:
Power output is the amount of sound energy emitted into the water
by the sonar transmitter. Power output is measured using either RMS (Root Mean
Square) or P-T-P (Peak-to-Peak) measurement systems. Either method is acceptable,
but it is important, when comparing power outputs, to make sure that the same
measurement system is being used for both outputs, because P-T-P numbers are 8
times higher than RMS numbers. Greater power output allows the sonar signal to
penetrate through weeds and thermoclines, reach deeper depths and operate more
effectively in noisy environments, such as when the boat is running at high speed.
Pulse Width (Pulse Length):
Pulse Width is the length of time that a sonar sound
burst is transmitted into the water. Shorter pulse widths provide better target
separation, but cannot travel to great depths. Longer pulse widths provide better
depth penetration, but result in poorer target separation. Humminbird® varies
pulse width based on depth to optimize both target separation and depth
performance. See
Target Separation
.
QuadraBeam
TM
:
QuadraBeam
TM
is a Humminbird® sonar configuration that uses
four sonar beams for a more detailed bottom image. QuadraBeam
TM
uses the
DualBeam PLUS
TM
configuration for downlooking, and also adds two additional
beams to look to the left and right. The sonar beams pointing to the left and right
provide the ability to spot fish and structure over a wide 90° area, and to identify on
which side of the boat they are located. See
DualBeam PLUS
TM
.
Quick Disconnect Mount:
The Quick Disconnect Mounting system is an exclusive
Humminbird® feature that permits the unit to be easily removed from the
mounting base by pressing a release button, and re-installed by simply snapping it
back into place. All cable connections are made when installing, so that no separate
wiring connections are required. Additionally, the mount offers 90° tilt and 360°
swivel capability to adjust the viewing angle of the unit as you move about the boat.
Real Time Sonar:
Real Time Sonar is a Humminbird® technology that delivers ultra-
fast sonar transmitter/receiver operation and results in a more detailed
instantaneous view of what is under the boat. The Real Time Sonar window is a
vertical band at the right side of the display that shows the instantaneous sonar
return from the transducer at a particular instant. The RTS® Window menu option
permits the user to adjust the window to show the full sonar signal return, or just a
narrower band that indicates intensity using grayscale. Real Time Sonar relies on
very fast Sonar Update Rate (Ping Speed). See
Sonar Update Rate
.
Receiver:
See
Transmitter
.
Second Return:
The Second Return is a term that describes the appearance of a
second sonar return below the primary sonar return (bottom contour) at exactly
twice the true depth. The second return is caused by the same sonar energy
bouncing off the bottom once, rebounding to the water surface and then traveling
back down to the bottom to be reflected again. Second returns are more common
in shallow water and over hard bottoms; it is actually possible to see a third sonar
return under some circumstances. The second return provides useful information to
help determine bottom hardness, as areas with harder bottoms will generally create
a second return. The second return can be used as a guide to set Sensitivity when in
shallower water.
Sensitivity:
Sensitivity is a user feature that adjusts the sensitivity of the sonar
system to show more or less detail in the water. Higher sensitivities are often
preferred, however, when the water contains debris (silt, storm debris, etc.) and it
can be difficult to pick out targets. Conversely, if sensitivity is set too low, relevant
targets may be missed.
SONAR:
SONAR is the acronym for SOund and NAvigation Ranging. Sonar
technology uses precision sound bursts transmitted underwater to determine the
distance and other attributes of objects in the water. Distance can be determined
because the speed of sound in water is constant, and the time for the signal to
return is measured. Sound also travels very quickly underwater, making sonar a
responsive, cost-effective tool. Sonar is the basic technology behind all recreational
and commercial fishfinding and depthfinding devices.
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