Humminbird 500 series Operation Manual page 11

the area under and adjacent to your boat, including the following items:
device is connected to the Fishfinder.
83 kHz, Wide Beam Hollow Fish Symbol
(ONLY available on Dual Beam Units)
Structure - where fish may be hiding.
Fish - fish are displayed as arches and/or
fish icons, and the unit can be set to alarm
when a fish of a certain size is detected.
When a target is detected and Fish ID+
on, a Fish ID+ TM
displayed. The size of the symbol shows the
intensity of the sonar return. The unit will
clearly show schools of Bait Fish as "clouds"
of different shapes and sizes, depending on
the number of fish and boat speed.
200 kHz, Narrow Beam Shaded Fish Symbol
Thermoclines - layers of water with
different temperatures that appear at
different depths and different times of the
year. A thermocline typically appears as a
continuous band of many gray levels moving
across the display at the same depth.
Soft Bottom
RTS® (Real Time Sonar) Window
Battery Voltage - the voltage of the boat's
battery; can be set to alarm if the voltage
falls below a certain point.
6
symbol with depth is
TM is