Humminbird 408930-1 GPS Receiver User Manual


 
What’s on the Down Imaging™ Display
Down Imaging™ uses its unique transducer and sonar technology to provide
definition profiling beams produce the detailed sonar data that you see on the
can interpret the structure and bottom contour, including the following items:
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What’s on the Down Imaging™ Display
NOTE: Entries in this view that list (with Temp/Speed or GPS Receiver) are available if
then only the information from the GPS receiver will be displayed on the view.
Depth - Waterdepth canbe set to alarmwhen
the water becomes tooshallow.
Temperature - Water surface temperature.
Speed - If a GPS Receiver or Temp/Speed
accessory is connected, the Fishfinder can
display the speed of the boat and can keep a
Triplogof nautical or statute miles traveled.
Topography Changes - The light part of the
display shows where the beam is hitting hard
bottom or rising terrain. The dark part of the
display indicates soft bottom (sand, mud) or
descending terrain.
BottomReturn-Usetheappearanceofthebottom
return to determine bottom hardness. Rock and
gravel provide a clearer sonar return than
mud and sand because hard objects reflect
sonar better than soft objects.