Humminbird 561 Fish Finder User Manual


 
4
How Sonar Works
Single Beam Sonar
(550, 560)
The 550 Fishfinder and 560 Fishfinder use a
200 kHz single beam sonar system with a 20°
area of coverage. Depth capability is affected by
such factors as boat speed, wave action, bottom
hardness, water conditions, and transducer
installation.