Furuno GP-1650DF, GP-1650F manual Surface noise/Aeration, Surface noise/aeration

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Surface noise/Aeration

When the waters are rough or the boat passes over a wake, surface noise may ap- pear near the zero line. As surface turbulence is acoustically equivalent to running into a brick wall, the bottom echo will be displayed intermittently. Similar noise sometimes ap- pears when a water temperature difference (thermocline) exists. Different species of fish tend to prefer different temperature zones, so the thermocline may be useful to help iden- tify target fish. 200 kHz tends to show shal- low thermoclines better than 50 kHz.

In rough waters the display is occasionally interrupted due to below-the-ship air bubbles obstructing the sound path. This also occurs when the boat makes a quick turn or reverses movement. Lowering the picture advance speed may reduce the interruption. However, reconsideration of the transducer installation may be necessary if the interruption occurs frequently.

Surface noise

Caused by aerated water

Thermocline

Figure 2-34 Surface noise/aeration

2-12

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Contents Color DGPS/PLOTTER/SOUNDER Color GPS/PLOTTER/SOUNDER 199 Do not disassemble or modify the equipment About the TFT LCDDo not open the equipment Do not operate the equipment with wet handsTable of Contents Declaration of Conformity SpecificationsSounder Setup Options IiiWord to GP-1650DF/1650F Owners FeaturesForeword System Configuration Display UnitThis page is intentionally left blank Operational Overview Display Unit ControlsTurning the power off Inserting Mini Chart CardTurning the Power On/Off Display abbreviationsSelecting a display Adjusting Tone and BrilliancePlotter Displays Plotter/Sounder Display Sounder DisplaysMenu Operation, Soft Keys Normal Sounder Display10 Demo setting screen Demonstration DisplayThis page is intentionally left blank Video Sounder Operation Principle of OperationKHz picture Sounder Display DescriptionNormal sounder display indications, markers Marker zoom display Selecting sounder display modeBottom-zoom display Bottom-lock displayScope display Plotter/Sounder DisplayDual-frequency Display EnterAutomatic Sounder Operation Manual Sounder OperationSelecting display range Adjusting the gainMeasuring Depth Range shiftingSuppressing Interference Suppressing Low Level NoiseErasing Weak Echoes White MarkerBackground and echo colors Selecting Picture Advance SpeedSelecting Background and Echo Colors Alarms Fish school echoes Interpreting the DisplayZero line Bottom echoSurface noise/Aeration 34 Surface noise/aerationNorth-up Plotter DisplaysPresentation Modes Course-upCursor Selecting Chart Scale/RangeMini Chart Cards Shifting the DisplayChart symbols Indices and chart enlargementRemarks on chart display Furuno mini chart cardAid to navigation data Port service icons Nav-Charts cardsComparison of Furuno and Nav-Charts chart cards GPS satellite monitor display Navigation Data DisplayEnlarging an indication Beacon information display How to read the compass displaySteering Display Highway Display How to read the XTE scaleSetting the range of the XTE scale Navigation Trip Distance Changing Operation ModeFifure 3-16 Display setup1 menu FishingTracking TrackDisplaying Track Track Plotting Method, Interval Stopping/Restarting Plotting of TrackChanging Track Color Track plotting methodTrack Memory Changing Track Memory CapacityTrack plotting interval Erasing All Track Plotter display MarkEntering Marks Video sounder display Changing Mark AttributesVideo sounder display Small Changing Mark SizeTions Erasing individual marks/lines Erasing MarksDisplaying Track and Mark Points Erasing whole marks/linesEntering waypoints at own ship’s position WaypointsEntering Waypoints Entering waypoints at MOB positionWaypoint menu Changing the shape and color of waypoint markEntering waypoints by latitude and longitude position Changing waypoint name, comment, proximity alarm radiusEntering waypoints by range and bearing Changing waypoint positionErasing waypoints through the waypoint list Erasing Individual WaypointsChanging Waypoint Data Erasing waypoints by the cursorSearching Waypoints Waypoint Mark SizeChanging Waypoint Position on the Plotter Display This page is intentionally left blank Entering routes through the route list RoutesEntering Routes AbcdefEntering routes by the cursor Connecting RoutesInserting, Removing Waypoints Inserting waypoints through the route listAlph List Inserting waypoints on the plotter displayRemoving waypoints from routes WPTCreating Track-based Routes Removing route waypoints from the plotter displayErasing Routes Save icon appearance On the plotter displayThis page is intentionally left blank Selecting quick point entry method NavigationNavigating to Quick Points Navigating to a single quick pointNavigating to Ports, Port Services Navigating to Waypoints waypoint listNavigate directly to a route waypoint Following a RouteNavigate route waypoints in reverse order Navigate along specific leg of routeRestarting navigation Setting speed for ETA calculationSwitching waypoints Cancelling Navigation This page is intentionally left blank Arrival Alarm Plotter AlarmsAudio Alarm On/Off IntroductionAnchor Watch Alarm XTE Cross Track Error AlarmSpeed Alarm Proximity AlarmAlarm messages and their meanings Alarm InformationAlarm messages 10-1 Saving Data to Memory CardFormatting Memory Cards Saving data10-2 Error messageLoading Data from Memory Card Data overwriteTrack Configuration10-3 Waypoint/routeThis page is intentionally left blank Customizing Your Unit Chart Setup Options menuChart Offset menu 11-1Display Options menu Chart Details menuChart details menu description 11-2Display setup1 menu description 11-3Display SETUP2 menu description 11-411-5 GPS Setup Options menu description11.3 GPS/DGPS/TD Options menu 11-6 Dgps Setup Options menuDgps Setup Options 11-7 TD Setup menuTD Setup Displaying Loran C TDsRange Setup soft key Sounder Setup Options menuSounder Setup Options menu description 11-811-9 System Setup soft keySystem Setup menu description Echo Offset 200kHz, Echo Offset 50kHzSetup NMEA/DGPS Port 2 menu description Configuration menuSetup Nmea Port 1 menu description 11-10XON/XOFF 11-11UPLOAD/DOWNLOAD Data menu Download waypoint/route to PC11-12 22 Connection of GP-1650DF/GP-1650F to PCSystem Menu description 11-13System menu This page is intentionally left blank Using C-MAP NT Model 12-2 Example of caution area window12-3 Objects window12-4 13 Plotter displaySetting Chart Setup Options 12-6 20 Depth Info display12-7 21 Memory, I/O test resultsThis page is intentionally left blank Recommended maintenance program Maintenance & TroubleshootingMaintenance 13-1Simple troubleshooting plotter Replacement of Fuse, BatterySimple Troubleshooting 13-2Error messages Error MessagesSimple troubleshooting sounder 13-3Memory, I/O port test Diagnostic Tests13-4 TestDisplay test 13-5Keyboard test Clearing Memories 13-6Furuno chart Menu TreeSounder Setup Options Audio Alarm ON, OFF Loran C Chains Decca Chains World Time Geodetic Chart List Display Section GeneralGPS Receiver PlotterCoating Color Index Index-1Index-2 Index-3