Humminbird 343c Operation Manual page 66

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™.
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.) it can be
difficult to pick out targets. Conversely, if sensitivity is set too low, relevant targets
may be missed.
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