Fish Sensitivity; Real Time Sonar (Rts®) Window (Sonar View Only); Sonar View - Humminbird 515 Operation Manual

When Fish ID+ is turned off, the FishFinder shows only the raw sonar returns on the
display. For dual beam Fishfinders, when Fish ID+ is turned off, only the narrow
beam is used to detect sonar returns. These returns will often result in "arches"
forming on the display, indicating potential targets. Due to the transducer beam
angle, the distance to a fish decreases as the fish moves into the beam, and then
increases as it moves out again, creating a Fish Arch when this distance change is
shown on the display. Boat speed, chart speed, and the position of the fish within
the sonar beam greatly affect the shape of the arch.
Transducer Cone and Fish Arches
To turn Fish ID+ on or off:
1. Highlight Fish ID+ on the Sonar main menu.
2. Use the LEFT or RIGHT 4-Way Cursor Control keys to turn the Fish ID+ setting
On or Off. (On, Off, Default = On)

Fish Sensitivity

Fish Sensitivity
Fish Sensitivity adjusts the threshold of the Fish ID+
detection algorithms. Selecting a higher setting allows weaker returns to be
displayed as fish. This is useful for identifying smaller fish species or baitfish.
Selecting a lower setting displays fewer fish from weak sonar returns. This is
helpful when seeking larger species of fish. Fish Sensitivity is used in conjunction
with Fish ID+. Fish ID+ must be On for Fish Sensitivity to affect the ability of the
FishFinder to identify sonar returns as fish.
To change the Fish Sensitivity setting:
1. Highlight Fish Sensitivity on the Sonar main menu.
2. Use the LEFT or RIGHT 4-Way Cursor Control keys to change the Fish
Sensitivity setting. (Low = 1, High = 10, Default = 5)
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R eal Time Sonar (R
R eal Time Sonar (R
(Sonar View Only) (Sonar View Only)
RTS® Window sets the RTS window to either Wide or Narrow, or turns it off in the
Sonar View. The RTS window always updates at the fastest rate possible and only
displays returns that are within the transducer beam. (See Real Time Sonar (RTS)
Window for additional detail).
RTS Window (Wide) RTS Window (Narrow)
To change the RTS Window setting:
1. Highlight RTS Window on the Sonar main menu.
2. Use the LEFT or RIGHT 4-Way Cursor Control keys to change the RTS Window
setting. (Wide, Narrow, Off, Default = Off)
TS®) Window
TS®) Window
RTS Window (Off)
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