Garmin GPSMAP 2106, 2110 Owner's Manual

Also see for GPSMAP 2106 - Marine GPS Receiver: Quick reference guide Install guide Installation instructions

Contents

Garmin GPSMAP 2106, 2110 Owner's Manual Manual pdf 80 page image

72 GPSMAP 2106/2110 Owner’s ManualU SING SONAR > U NDERSTANDING SONARU SING SONARThis section covers the additional options for the GPSMAP 2106/2110 whenused with a GSD 20, GSD 21, or GSD 22 Sounder Module. Read the installationinstructions included with your Garmin Sounder Module to install itNOTE: You must have a GSD 20, GSD 21, or GSD 22 Sounder Moduleinstalled and connected to your GPSMAP 2106/2110 to use the sonar features.Understanding SonarThe transducer mounted on your vessel sends sound waves down into the waterin a cone shape, similar to a flashlight beam (covering a smaller circular area atthe top and angling out to a larger circular area at the bottom). These sound wavesreflect off of any object that they hit, and then the waves travel back up to thetransducer. These objects could be fish, branches, the bottom, or any other objectthat has a density that is different from the water. The transducer receives thesound wave information and then sends the information to the GSD 20, GSD 21,or GSD 22 sounder module and then to the GPSMAP 2106/2110. TheGPSMAP 2106/2110 displays the information on the screen for you to see andinterpret. The type of transducer and the settings that you choose determine howthe information appears on the screen.Using Dual FrequencyDual frequency works best for deep water (off-shore) applications. The200 kHz frequency allows you access to great detail about what is underneathyour boat. The 50 kHz frequency provides less detailed information, butpenetrates to greater depths with the same power. You can choose either or bothfrequencies to get the information that you want. If you choose dual frequency,the transducer alternates between the 50 kHz and 200 kHz signals. This capabilityallows you to see the best picture available at any depth.Using Dual BeamDual beam works best for shallow water (for example, inland) applications.A dual beam transducer can transmit a narrow or a wide beam. The water areacovered by the transmitted sound waves is determined by the beam width of thetransducer and the water depth. The narrow beam provides crisp detail of what isunder your boat, and is very helpful if you are fishing in deeper water where thebeam covers more area (for example, at a 30-foot depth, the narrow beam coversthe area of about a 7-foot circle).WideBeamNarrowBeamThe wide beam is more helpful in shallow water, because it gives you a muchwider view of objects in the water, including areas beyond the sides of your boat.At a 30-foot depth, the wide beam covers the area of approximately a 20-footcircle.