NorthStar Navigation GPS Receiver M121 User Manual

M121/M84  
Multi-Function Unit  
Installation and Operation Manual  
www.northstarnav.com  
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Contents  
1 Introduction ............................................................................................................................................................................. 5  
1-1 Overview . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6  
1-2 Cleaning and maintenance . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6  
1-3 Plug-in cards . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7  
1-4 Removing and replacing the display unit . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8  
2 Basic Operation.......................................................................................................................................................................... 9  
2-1 Using the keys . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 11  
2-2 Turning on and off / auto power . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 12  
2-3 Backlight and night mode . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 12  
2-4 Man overboard (MOB). . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 13  
2-5 Alarms. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 13  
2-6 Simulate mode . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 14  
2-7 The main windows . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 14  
3 Navigation: Chart..................................................................................................................................................................... 19  
3-1 Introduction to navigating. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 19  
3-2 Chart window . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 21  
3-3 Distance and bearing calculator . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 23  
3-4 Projected course . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 24  
3-5 Tracks and tracking. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 24  
4 Video window .......................................................................................................................................................................... 25  
5 Navigation: Highway window .................................................................................................................................................. 26  
6 Navigation: Waypoints............................................................................................................................................................. 26  
6-1 Waypoints window . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 27  
6-2 Managing waypoints . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 27  
7 Navigation: Routes .................................................................................................................................................................. 29  
7-1 Routes window . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 29  
7-2 Managing routes . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 29  
8 Satellites ................................................................................................................................................................................. 32  
8-1 Satellite window. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 33  
9 Sonar fishfinding: Introduction ............................................................................................................................................... 33  
9-1 Using the Instrument . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 33  
9-2 Interpreting the display. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 34  
9-3 Single and Dual frequency fishfinding. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 36  
9-4 Fish detection and display. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 39  
9-5 Range . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 40  
9-6 Gain and threshold. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 41  
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10 Sonar fishfinding: Windows ................................................................................................................................................... 42  
10-1 Sonar history window - no split . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 42  
10-2 Sonar Zoom and Full Screen Zoom displays . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 43  
10-3 Sonar Bottom window . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .44  
10-4 Sonar 50/200 window. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .44  
10-5 Sonar A-Scope window . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 45  
11 Gauges window...................................................................................................................................................................... 46  
12 Data window.......................................................................................................................................................................... 46  
13 Fuel functions and display...................................................................................................................................................... 47  
13-1 What the fuel computer does. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 47  
13-2 Fuel display . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 47  
13-3 When you add or remove fuel . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 48  
13-4 Low fuel alarm . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 49  
13-5 Boat speed sensors. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 49  
13-6 Fuel consumption curves. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 51  
13-7 Calibration . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 53  
14 Tides window ......................................................................................................................................................................... 54  
15 User card window................................................................................................................................................................... 55  
16 AIS ......................................................................................................................................................................................... 57  
16-1 Viewing AIS Vessels . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 57  
16-2 Dangerous Vessels . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 58  
16-3 AIS Windows . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 58  
17 DSC/Buddy track windows ...................................................................................................................................................... 60  
17-1 The windows . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 60  
17-2 Using the windows . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 61  
18 Radar .................................................................................................................................................................................... 62  
18-1 Radar window. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 62  
18-2 Radar modes . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 63  
18-3 Enabling the radar functionality . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 63  
18-4 Selecting standby mode or transmit mode. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 63  
18-5 Disabling the radar functionality . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 63  
18-6 Adjusting the quality of the radar window . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 63  
18-7 Changing the echo expansion setting . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 65  
18-8 Turning the target trails on or off . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 66  
18-9 Using the VRM/EBL. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 66  
18-10 Changing the PPI position. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 68  
18-11 Using the radar guard zones. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 68  
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19 Setting up the M121/M84 ....................................................................................................................................................... 70  
19-1 Setup > System . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 71  
19-2 Setup > Chart . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 72  
19-3 Setup > Sonar . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 75  
19-4 Setup > Radar . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 76  
19-5 Setup > GPS . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 79  
19-6 Setup > Fuel . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 80  
19-7 Setup > Track. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 81  
19-8 Setup > AIS. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 82  
19-9 Setup > Logs . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 83  
19-10 Setup > Alarms. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 84  
19-11 Setup > Units. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 85  
19-12 Setup > Comms . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 85  
19-13 Setup > Calibrate. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 86  
19-14 Setup > Time . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 87  
19-15 Setup > Favorites. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 88  
19-16 Setup > Simulate . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 88  
20 Installation ........................................................................................................................................................................... 89  
20-1 Installation: What else comes with my M121/M84?. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 90  
20-2 Installation: Options and Accessories . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 91  
20-3 Installation: The display unit. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 92  
20-4 Installation: Power/data cable. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 94  
20-5 Installation: GPS antenna . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 95  
20-6 Installation: Sonar transducer . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 96  
20-7 Installation: Northstar petrol/gasoline sensors . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 96  
20-8 Installation: SmartCraft. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 97  
20-9 Installation: Radar . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 97  
20-10 Installation: Other NavBus instruments. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 98  
20-11 Installation: Other NMEA instruments . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 99  
20-12 Installation: Setup and test . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 99  
Appendix A - Specifications....................................................................................................................................................... 100  
Appendix B - Troubleshooting................................................................................................................................................... 103  
B-1 General problems . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .103  
B-2 GPS navigation problems. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .104  
B-3 Fuel consumption problems. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .104  
B-4 Sonar fishfinding problems . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .105  
B-5 Radar problems . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .107  
Appendix C Glossary and navigation data ................................................................................................................................. 108  
Appendix D Compliance statements...........................................................................................................................................111  
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Warning  
It is your sole responsibility to install and use the instrument and transducer(s) in a manner  
that will not cause accidents, personal injury or property damage. Always observe safe boating  
practices.  
The choice, location, and installation of transducers and other components of the system are  
critical to the performance of the system as intended. If in doubt, consult your Northstar dealer.  
To reduce the risk of misusing or misinterpreting this instrument, you must read and understand  
all aspects of this Installation and Operation Manual. We also recommend that you practice all  
operations using the built-in simulator before using this instrument at sea.  
Global Positioning System: The Global Positioning System (GPS) is operated by the US  
Government which is solely responsible for its operation, accuracy and maintenance. The GPS  
is subject to changes which could affect the accuracy and performance of all GPS equipment  
anywhere in the world, including this instrument.  
Electronic Chart: The electronic chart used by this instrument is an aid to navigation designed  
to supplement, not replace, official government charts. Only official government charts  
supplemented by notices to mariners contain the information required for safe and prudent  
navigation. Always supplement the electronic information provided by this instrument with  
other plotting sources such as observations, depth soundings, radar and hand compass bearings.  
Should the information not agree, the discrepancy must be resolved before proceeding any  
further.  
AIS: The AIS features on this chart-plotter are designed as a safety aid only and do not guarantee  
safety at sea. AIS transmission is mandatory on some, but not all, vessels. You should check  
your local laws and regulations for requirements in your area. As a result of different legal  
requirements, different vessel sizes and uses, you should not assume that your AIS equipped  
chart-plotter will show the location of ALL vessels in your area. Careful prudence, judgement, and  
safe navigation practices should always be exercised. AIS should be used to complement radar,  
but AIS is not a substitute for radar.  
Sonar performance: The accuracy of the sonar depth display can be affected by many  
factors, including the type and location of the transducer and water conditions. Never use this  
instrument to gauge depth or other conditions for swimming or diving.  
Fuel data: Do not rely on this instrument as the sole source of information about fuel available  
onboard. You must supplement this instrument’s fuel data with visual or other checks of the  
fuel available. This is necessary because possible operator errors, such as forgetting to reset the  
fuel used when filling the tank or running the engine with this instrument not switched on, can  
render this instrument inaccurate. Fuel economy can change drastically depending on boat  
loading and sea conditions. Always carry adequate fuel onboard for the intended trip, plus a  
reserve to allow for unforeseen circumstances.  
Simulate mode: Never have simulate mode on when you are navigating on the water.  
Failure to adhere to these warnings may lead to death, serious injury or property  
damage. Northstar disclaims all liability for installation or use of this product that  
causes or contributes to death, injury or property damage or that violates any law.  
4
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1 Introduction  
Quick reference to the built-in and optional features:  
Feature  
General  
Type  
See  
Requires  
How to use the keys and windows  
Troubleshooting  
2
Appendix B  
Simulate mode  
2-6  
Glossary of special names  
Specifications  
Appendix C  
Appendix A  
MOB  
Man overboard key  
2-4  
3-1  
3-2  
3-1  
3-1  
3-4  
3-5  
8-1  
15  
Navigation  
Overview of how to navigate  
Finding the boat’s position on the chart  
Navigate to any point or to a waypoint  
Navigate along a route  
GPS fix  
Projected course: An estimate of progress  
Tracks: records of where the boat has been  
GPS receiver status  
Saving and loading data with a user card  
Chart features (built in world chart)  
Chart details  
User card  
Chart data  
3-2  
3-2-4 & 5  
14  
Chart card  
Chart card  
Tides at a port  
AIS  
16  
Alarms  
Built in alarms  
2-5  
2-7-3  
2-7-4  
12  
Boat data  
Data at top of main displays  
Compass at top of main displays  
Dedicated data display  
Fuel  
Fuel computer, Instrument petrol/gasoline engine  
Fuel computer, SmartCraft engines  
What to do when you add or remove fuel  
Overview of the depth sounder  
Depth, bottom features, water features  
Fishfinder  
13  
Fuel sensors  
SmartCraft  
13  
13-1  
9
Sounder  
Sounder  
Sounder  
Sounder  
DSC VHF  
DSC VHF  
9
9
Other boats  
Track your buddy, polling other boats  
Distress calls  
17  
17  
(Continued next page)  
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Radar  
Overview of the radar  
18  
Radar  
Radar  
Radar  
Radar  
Radar  
Radar  
Radar  
The radar window explained  
18-1  
Change the radar operation mode  
Change the radar rotation or motion mode  
Optimize the quality of the radar window  
Find range and bearing with VRM/EBL  
Set up the radar guard zones  
18-2  
18-6, 18-7  
18-9  
18-10  
18-12  
1-1 Overview  
The M121/M84 can send data to other  
instruments, such as an autopilot, and  
receive data from other instruments.  
The Northstar M121/M84 is a rugged, highly  
integrated marine chartplotter and fishfinder.  
It is easy to use and has a high resolution color  
display. Complex functions can be performed  
with only a few key presses, taking the hard  
work out of boating.  
Radar functions require an optional  
Northstar radar system to be installed. Three  
radar systems are available; 2 kW, 4 kW, or 6  
kW.  
The available functions depend on the optional  
sensors and instruments that are installed:  
AIS functions require an optional AIS receiver  
to be installed.  
The Video window requires the M121/M84  
to receive video from a compatible source,  
such as a camera.  
For information on installation options, see  
section 20.  
This manual describes how to install and  
operate the M121/M84. Special terms  
are explained in Appendix C. For more  
information on this instrument and other  
Northstar products, go to our website, www.  
northstarnav.com.  
Fuel functions require one or more petrol/  
gasoline or diesel fuel sensors to be installed.  
SmartCraft engine functions require a  
SmartCraft system to be installed. For  
information on using SmartCraft, see  
the SmartCraft Gateway Installation and  
Operation Manual.  
DSC/Buddy track functions require an  
appropriate Northstar DSC VHF radio to be  
installed.  
1-2 Cleaning and maintenance  
The Instrument screen is covered by a  
proprietary anti-reflection coating. To avoid  
damage, clean the screen only with a damp  
cloth and mild detergent when dirty or  
covered in sea salt. Avoid abrasive cleaners,  
petrol or other solvents. If a plug-in card gets  
dirty or wet, clean it with a damp cloth or mild  
detergent.  
paint, use only one coat of paint. Remove the  
previous coat of antifouling paint by sanding it  
lightly.  
To optimize performance, avoid walking on  
or jamming cables and connectors. Keep the  
transducer free of weed, paint and debris. Do  
not use a high pressure water blast on a speed  
sensor paddlewheel as it may damage the  
bearings.  
Cover or remove a transom-mounted  
transducer when repainting the hull. If painting  
over a through hull transducer with antifouling  
Push the dust cover over the display when the  
Instrument is turned off.  
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1-3 Plug-in cards  
The M121/M84 can use two kinds of C-MAP™  
SD-Card plug-in cards:  
CAUTION  
1. Chart cards have chart details required for  
navigating in a particular region. When  
you insert a chart card, the extra details  
automatically appear on the Chart window.  
You can plug in up to two chart cards  
at once. If the chart shows a region not  
covered by a chart card, then it displays a  
simplified built-in world chart.  
Handle plug-in cards carefully. Keep them  
in their protective cases when not plugged  
into the M121/M84.  
Keep the M121/M84 card cover closed at all  
times to prevent moisture from entering the  
card compartment.  
2. User cards store navigation data. A user card  
allows navigation data to be transferred  
to another compatible instrument (see  
section 15).  
Removing a plug-in card  
1
2
3
Turn the M121/M84 off  
(see section 2-2).  
Push the card down until it  
releases and can pop up.  
Lift the card out.  
Put the card in its case.  
Open the card cover on the  
right of the display.  
Inserting a plug-in card  
1
2
3
Hold the new card with the  
gold contacts on the far side.  
Push the card into an empty  
socket until it clicks.  
Close the card cover.  
Turn the M121/M84 on  
(see section 2-2).  
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1-4 Removing and replacing the display unit  
If the M121/M84 is bracket mounted then it can  
easily be removed for security.  
Replacing the display unit  
1
Plug the connectors into the back of the  
display unit:  
Removing the display unit:  
1
2
3
Turn the M121/M84 off (see section 2-2) and  
put the dust cover on.  
Match the connector’s color to the socket  
color.  
Loosen the knobs on the mounting bracket  
and lift the unit off the bracket.  
Insert each connector and turn the  
locking collar clockwise until it is finger  
tight.  
Unplug the connectors from the M121/M84;  
turn each locking collar anticlockwise until  
you can pull the plug out.  
Nothing will be damaged if a cable is  
plugged into the wrong socket by mistake.  
4
Store the M121/M84 in a dry clean place.  
2
Hold the M121/M84 in place on the  
mounting bracket. Tilt it for best viewing,  
then hand tighten the knobs on the  
mounting bracket. Remove the dust cover.  
Knob  
Mounting bracket  
8
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2 Basic Operation  
Overview of the M121 keys  
ESC  
q
w
– Go back to an earlier menu or window. In  
chart mode centers chart at boat’s position.  
DISPLAY  
– This is a powerful key that allows you  
to setup the display the way you want. Main  
displays can be saved as favorite displays for easy  
access from the  
key.  
MENU  
e
– Show a menu of the options for the  
current active window.  
ENTER  
r
t
– Start an action or accept a change.  
/
– Changes the range on a window eg. Chart  
or Sonar zooms  
– Cursor keys, to move the cursor or  
the selection highlight.  
y
u
,
,
,
– The  
key selects which window you  
are working with. The Active window is indicated  
with a red border.  
1
i
o
– The  
key allows you to quickly  
2
switch between your saved favorite displays.  
5
6
GOTO  
AUTO  
– For a navigation display: Start navigating  
to a point, waypoint or along a route (see section  
3-1-2). For sonar display: Select a sonar operating  
mode (see section 6).  
3
4
7
SETUP  
a
s
– The setup key takes you to the setup  
menu which allows advanced configuration of  
the M121.  
8
9
– This key places a waypoint on the Active  
Chart Window.  
d
f
– Man overboard (MOB, see section 2-4).  
10  
11  
– Turn Instrument on and off (see section 2-2);  
adjust the backlighting (see section 2-3).  
12  
13  
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Overview of the M84 keys  
ESC  
q
w
– Go back to an earlier menu or window. In  
chart mode centers chart at boat’s position.  
DISPLAY  
– This is a powerful key that allows you  
to setup the display the way you want. Main  
displays can be saved as favorite displays for easy  
access from the  
key.  
MENU  
e
– Show a menu of the options for the  
current active window. The setup menu can be  
MENU  
opened by pressing  
twice.  
ENTER  
r
t
– Start an action or accept a change.  
/
– Changes the range on a window eg. Chart  
or Sonar zooms  
– Cursor keys, to move the cursor or  
the selection highlight.  
y
u
,
,
,
– The  
key selects which window you  
1
are working with. The Active window is indicated  
with a red border.  
i
o
– The  
key allows you to quickly  
2
6
5
switch between your saved favorite displays.  
– This key places a waypoint on the Active  
Chart Window.  
3
4
a
s
– Man overboard (MOB, see section 2-4).  
7
– Turn Instrument on and off (see section 2-2);  
adjust the backlighting (see section 2-3).  
8
9
10  
11  
Note: Display refers to ALL windows and the data header/Compass  
Window refers to a part of the display in which a particular function is shown  
e.g. The Chart window on a Chart + Sonar display.  
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2-1 Using the keys  
In this manual:  
Changing data  
Press means to push the key for less than a  
second.  
First press or to move the highlight to the  
data to change, then:  
a) To change a tick box  
Hold means to hold the key down.  
means On or Yes  
The internal beeper beeps when a key is  
pressed (to adjust the beep volume, see section  
19-1).  
means Off or No.  
ENTER  
Press  
or to change the tick box.  
Using the menus  
b) To select an option  
Operate the Instrument by selecting items from  
menus. Items can be submenus, commands or  
data.  
ENTER  
1
2
Press  
to display the list of options.  
Press or to move the highlight to the  
option you want, then press  
ENTER  
.
Selecting a submenu  
c) To change a name or number:  
A
after a menu item indicates a submenu, for  
ENTER  
1
Press  
to display the name or number:  
example Chart . Press or to move the  
ENTER  
highlight to the submenu, then press  
.
Starting a command  
2
Press or to select a letter or digit to  
change. Press or to change the letter or  
digit.  
Press or to move the highlight to the  
command, for example Goto cursor, then press  
ENTER  
.
Repeat this to change other letters or  
numbers.  
ENTER  
3
Press  
ESC  
to accept the new value. Or press  
to ignore the changes.  
d) To change a slider value  
Press to decrease the value or to increase  
the value.  
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2-2 Turning on and off / auto power  
Turning on manually  
Auto power  
If the Instrument is not wired for auto power,  
press to turn the unit on. If necessary, adjust  
the display to be easy to read (see section 2-3).  
If the Instrument is wired for auto power (see  
section 20-4), then:  
The Instrument automatically turns on when  
you turn the boat’s ignition switch on.  
You can not turn the Instrument off while  
the ignition switch is on.  
!
WARNING  
If the Instrument is not wired for auto power  
then the Instrument does not record engine  
hours and will not record fuel consumption  
if not powered (see section 18-4).  
If Auto power off (see section 19-1) is , the  
Instrument automatically turns off when you  
turn the boat’s ignition switch off.  
If Auto power off (see section 19-1) is , the  
Instrument stays on when you turn the boat’s  
ignition switch off. You can now turn the  
Instrument off manually.  
Turning off manually  
If the Instrument is not wired for auto power or  
if the ignition switch is off, hold down until  
the display turns off.  
2-3 Backlight and night mode  
To go to the Backlight window, press briefly.  
Night mode  
Night mode sets the palette for all windows.  
Backlight  
Normal palette, for daytime  
The display and keys are backlit. To change the  
backlight level, select Backlight, then press to  
dim or to brighten.  
A palette optimized for night time.  
To change mode, highlight Night mode, then  
ESC  
When you have finished, press  
ENTER  
press or  
. To change only the chart  
palette, see section 19-1.  
Tip: Press twice to give the brightest  
screen, with maximum backlight and Night  
mode off.  
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2-4 Man overboard (MOB)  
The MOB feature saves the boat’s position and  
then navigates back to this point.  
If the NMEA output (autopilot) is on, the  
Instrument asks if the autopilot is active.  
Select:  
No: Use the Instrument to manually navigate  
to the destination MOB waypoint (see  
sections 3-1-1 and 3-1-2).  
!
WARNING  
MOB will not work if the Instrument does  
not have a GPS fix.  
Yes: The Instrument asks if the boat is to go  
to the MOB waypoint.  
1
2
Press  
Select:  
The Instrument stores the boat’s position as  
a waypoint called MOB.  
Yes: to immediately start navigating to the  
MOB waypoint.  
The Instrument changes to the chart  
window, with the MOB waypoint at the  
centre of the chart.  
!
WARNING  
This might result in a sudden and dangerous  
turn.  
The chart zooms in for accurate navigation.  
If the chart can not show the required small  
scale, the Instrument changes to plotter  
mode (a white window with crosshatching  
and no chart details, see section 19-2).  
No: disengage the autopilot; then use the  
Instrument to manually navigate to the  
destination MOB waypoint (see sections  
3-1-1 and 3-1-2).  
3
The Instrument sets the MOB waypoint to  
be the destination to navigate to.  
If the NMEA output (autopilot) is off  
(see section 19-12) use the Instrument to  
manually navigate to the destination MOB  
waypoint (see sections 3-1-1 and 3-1-2).  
To cancel MOB or set another MOB  
1
2
Press  
again to display a menu.  
Select an option from the menu.  
Tip: The MOB waypoint remains on the chart  
after the MOB has been cancelled. To delete the  
MOB waypoint, see section 6-2-5.  
2-5 Alarms  
ESC  
When the Instrument detects an alarm  
condition, it displays a warning message on  
the display, the internal beeper sounds and any  
external beepers or lights operate.  
Press  
to clear the alarm. The alarm will  
sound again if the alarm condition occurs again.  
The Instrument has user settable alarms (see  
section 19-10).  
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2-6 Simulate mode  
In Simulate mode, the Instrument ignores data  
from the GPS antenna and other transducers  
and sensors and the Instrument generates this  
data itself. Otherwise, the Instrument functions  
normally.  
To start and stop Simulate mode, and for more  
information, see section 19-16. In simulate  
mode, Simulate or Demo flashes at the bottom  
of the window.  
There are two simulate modes:  
!
WARNING  
Normal: Allows a user to become familiar  
with the Instrument off the water.  
Never have Simulate mode on when using  
the Instrument to navigate on the water.  
Demo: Simulates a boat moving along a  
route and automatically displays different  
Instrument functions.  
2-7 The main windows  
DISPLAY  
To show one of the main windows full-size, press  
and select the window.  
Note  
1
The windows available depend on the optional sensors and instruments that are installed (see  
section 1-1).  
2
Set up commonly used windows as favorites and press  
section 2-7-2).  
to switch between windows (see  
14  
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DISPLAY  
To show one of the other windows full-screen, press  
, select More... and select the window.  
ESC  
Press  
to return from one of these  
windows to the previous window.  
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ENTER  
2-7-1 Multi window displays  
3
Press  
.
The M121/M84 can show up to four windows  
at once, for example Chart, Sonar, Gauges and  
Video:  
Deleting a window from the display  
1
2
Press  
until the window you want to  
delete has a red border.  
DISPLAY  
Press  
and select Delete window.  
Exchanging two windows on the display  
1
Press  
until the first window has a red  
border.  
DISPLAY  
2
Press  
, select Replaceand select the  
second window.  
The M121/M84 exchanges the two windows.  
Replacing a window on the display  
1
Press  
until the window that you want  
to replace has a red border.  
Adding a window to the display  
DISPLAY  
2
Press  
, select Replaceand select a new  
DISPLAY  
Press  
, select Add windowand select a  
window that is not currently visible.  
window to add. The M121/M84 automatically  
rearranges the display to show the new  
window.  
Note  
1
When some windows are small then not all  
the data is shown.  
Changing window size  
DISPLAY  
2
Set up commonly used displays as favorites  
1
2
Press  
and select Split ratio.  
and press  
to switch between displays  
Press or to change the width of the  
windows. If the M121/M84 is displaying three  
or four windows, press or to change  
the height of the windows.  
(see section 2-7-2).  
Note: Some windows are fixed in size.  
The active window  
If there is more than one window displayed, the active window is indicated by a red border. To  
change the active window to the next window, press  
.
MENU  
Pressing  
will display the options menu for the active window.  
Red border  
Press  
Press  
Chart is active  
Sonar is active  
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3
Select where in the list to add the new  
favorite. If you select an existing favorite  
display then the new favorite will replace the  
existing favorite in the list.  
2-7-2 Favorite displays  
The M121/M84 has a list of commonly used  
displays, called favorite displays. There can be  
up to six favorite displays.  
Each display can have one or more windows  
plus a data header (see section 2-7-3) and a  
compass (see section 2-7-4). Set up favorite  
displays for common situations, for example  
navigating along a route, travelling in a harbour,  
fishing.  
Selecting a favorite display  
Deleting a favorite display from the list  
MENU  
1
2
Press  
twice then select Favorites.  
MENU  
Highlight the display to delete, press  
and select Delete.  
Changing the order of the favorites list  
To select another favorite, press  
more times. For example, with six favorites:  
one or  
MENU  
1
2
Press  
twice then select Favorites.  
MENU  
Highlight the display to move, press  
and select Move up or Move down.  
Adding a favorite display to the list  
1
Set up the display with the window or  
windows you want in the new favorite (see  
sections 2-7-1 and 2-7-4).  
DISPLAY  
2
Press  
and select Save this display. The  
M121/M84 displays the favorites list.  
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Tip: If all fields in a line are None then the  
line will not be displayed and the data header  
will take less space on the display.  
ESC  
2-7-3 Data header  
The displays can show data at the top, called  
the data header.  
5
Press  
.
Tip: The data header will change when you  
select another display. To set a data header that  
you can recall later, set the header as part of a  
favorites display (see below).  
Favorites displays and data headers  
When you select a window from the display  
menu (see section 2-7) the M121/M84  
displays an appropriate data header for the  
window.  
To set a data header for a favorites display,  
follow the steps to add a favorite (see section  
2-7-2 - Adding a favorite display to the list). In  
step 1, set the data header for the favorite as  
described above.  
Each favorite display (see section 2-7-2) has  
its own data header. When you press  
to recall a favorite display, the M121/M84  
recalls the favorite displays data header.  
2-7-4 Compass  
The chart, sonar and highway displays can show  
a compass at the top of the window.  
Setting the data header for a display  
The compass always shows the boat’s course  
over ground (COG), a black symbol in the  
middle. When the boat is navigating to a  
point, the compass also shows bearing to the  
destination (BRG), a red symbol.  
DISPLAY  
1
2
Press  
and select Data header.  
To turn the data header on or off:  
Select Data.  
ii Select or  
To select the size of the data:  
Select Size.  
i
.
In this example, BRG is 260°M and COG is 321°M.  
3
4
To turn the compass off or on:  
i
MENU  
1
2
Press  
and select Data header.  
ii Select the size to display.  
To change the data displayed:  
Set Compass to or  
.
i
Select Data setup.  
ii Change a data field:  
a
b
c
Press the cursor keys to highlight  
the field.  
ENTER  
Press  
to display a menu  
of data items.  
Select a data item that is available  
on your system or select None to  
leave the field empty.  
iii Repeat the above step to set the other  
data fields.  
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3 Navigation: Chart  
The chart window shows the chart, the boat’s position course and navigation data.  
3-1 Introduction to navigating  
The Instrument has two ways of navigating, going straight to a point or following a route.  
Note:  
3-1-1 Navigating to a point  
1
If the XTE alarm is enabled, an alarm will  
sound if the boat deviates too much from its  
intended course (see section 19-10).  
When the Instrument is navigating to a  
point, the chart and highway windows show  
navigation data:  
2
If the arrival radius alarm is enabled, then an  
alarm will sound to show that the boat has  
reached the destination  
A The boat position .  
B
The destination point marked with a circle.  
The boat’s plotted course to the destination.  
C
(see section 19-10).  
D Two CDI lines, parallel to the boat’s plotted  
course, which indicate the maximum  
3
When the destination is reached an  
arrival warning appears with the option  
to cancel navigation (goto or route). Yes  
the navigation is cancelled, nonavigation  
continues however XTE and highway are no  
longer displayed.  
expected deviation from the plotted course.  
For more information, see Appendix C.  
B
3-1-2 Going to a waypoint or to a point on the  
chart  
D
A waypoint is a position that you can set on the  
Instrument chart, for example a fishing spot or a  
point on a route (see section 6).  
A
D
C
Going to a waypoint from the chart  
window  
1
2
Go to the chart window.  
Move the cursor to the waypoint: either  
use the cursor keys or use Find (see section  
3-2-5).  
If the Instrument is connected to an autopilot,  
the Instrument will send data to the autopilot  
to steer the boat to the destination. Start the  
autopilot before starting to navigate to the  
point.  
MENU  
3
Press  
and select Goto waypoint.  
Going to a waypoint from the waypoints  
window  
1
2
Go to the waypoints window.  
If the Instrument has no autopilot, steer the  
boat manually:  
Press or to highlight the waypoint to go  
to.  
a
b
c
use the boat position and destination on the  
chart or highway windows  
MENU  
3
Press  
and select Goto.  
or use navigation data displayed on the data  
header (see section 2-7-3)  
or use COG and BRG on the compass (see  
section 2-7-4).  
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Going to a point on the chart  
Starting a route from the routes window:  
1
2
Switch to a chart window.  
1
2
Go to the routes window.  
Move the cursor to the destination point:  
Then follow step 3 as in starting a route  
either use the cursor keys or use Find (see  
from the chart window above.  
section 3-2-5).  
Navigating  
MENU  
3
Press  
and select Goto cursor.  
The Instrument navigates to each waypoint on  
the route in turn as described in section 3-1-1.  
The Instrument stops navigating to the  
waypoint at the end of the current leg and  
starts the next leg of the route:  
!
WARNING  
Make sure the course does not pass over  
land or dangerous waters.  
1
When the boat comes within 0.025 nm of  
the waypoint  
Navigating  
2
3
Or when the boat passes the waypoint  
Or if you skip the waypoint.  
The Instrument navigates to the point as  
described in section 3-1-1.  
Skipping a waypoint  
Cancelling navigating  
To skip a waypoint, go to a chart window, press  
MENU  
MENU  
Go to a Chart window, press  
Cancel goto.  
Tip: Before starting, create waypoints at  
points of interest. Create a waypoint at the  
start of the trip for you to navigate back to (see  
section 5-2-1).  
and select  
and select Skip. The Instrument starts  
navigating straight towards the next waypoint  
on the route.  
!
CAUTION  
3-1-3 Following a route  
Preparing  
Skipping a waypoint with the autopilot on  
might result in a sudden course change.  
A route is a list of waypoints that the boat can  
follow (see section 6).  
To create waypoints before creating the  
route, see section 6-2-1.  
Cancelling a route  
When the boat has reached the final waypoint,  
or to stop the boat following the route at any  
To create a route, see section 6-2-1.  
time, cancel the route. Go to a chart window,  
Starting a route from the chart window:  
MENU  
press  
and select Cancel route.  
1
2
3
Go to the chart window.  
MENU  
Press  
and select Start Route  
Press or to highlight the route to follow.  
ENTER  
Press  
.
4
The Instrument asks for the direction to  
traverse the route.  
Select Forward (the order the route was  
created) or Reverse.  
5
The Instrument displays the chart with the  
route marked and starts navigating from the  
start of the route.  
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3-2 Chart window  
To go to the Chart window:  
DISPLAY  
Press  
and select Chart  
A typical chart window shows:  
A
B
C
K
F
D
I
F
J
E
H
G
A Data header. To turn the data off or on or to  
change what data is displayed (see section  
2-7-3)  
Note:  
To change the types of information displayed  
on the chart, see section 17-2.  
B Compass (see section 2-7-4)  
C Chart scale (see section 3-2-3)  
D Boat position (see section 3-2-1)  
To change to a perspective view of the chart,  
see section 3-2-6.  
If the region on the chart is covered by a  
chart card then the card’s information is  
automatically displayed on the chart. If the  
region is not covered by a chart card then the  
chart displays a simplified built-in world chart  
which is suitable for planning and general  
interest.  
E
F
Boat track (see section 3-5)  
Boat course and CDI lines (see Appendix C,  
CDI).  
G Distance and bearing of cursor from boat  
H Land  
I
Sea  
J
The cursor (see section 3-2-1)  
!
WARNING  
K A typical waypoint (see section 6 )  
The built-in world chart does not show  
enough detail for navigation. When you  
use the M121/M84 to navigate, always use a  
chart card which covers the region.  
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position, and the latitude and longitude has a  
cursor symbol to show this:  
3-2-1 Chart modes  
The Chart has two modes:  
36° 29.841’ N or S Latitude  
Centre on boat mode  
175° 09.012’ E or W Longitude  
To switch to centre on boat mode in the chart  
ESC  
window, press  
. The boat is at the centre  
!
of the chart. As the boat moves through the  
water, the chart automatically scrolls to keep the  
boat in the centre of the chart. The cursor (see  
below) is turned off.  
WARNING  
When reading the boat position, make sure  
the position is not the cursor position.  
Cursor mode  
The keys  
and are called cursor keys. To  
3-2-3 Chart scale  
switch to cursor mode in the chart window, hold  
down a cursor key. The cursor appears and  
moves away from the boat:  
Press to zoom in and display a smaller area  
of the chart in more detail. Press to zoom out  
and display a bigger area in less detail.  
Press the key which points in the direction  
that the cursor will move, for example press  
to move the cursor down.  
The chart scale is displayed at the top left of the  
chart:  
Press midway between two of the cursor  
keys to make the cursor move diagonally.  
3-2-4 Chart symbols and information  
Hold a cursor key down to make the cursor  
move continuously across the window.  
The chart shows many kinds of symbols, such as  
waypoints, ports, marinas, buoys and beacons.  
If necessary, press or or to choose a chart  
scale where the symbol is displayed.  
In Cursor mode:  
The distance ( DST) and bearing ( BRG) of  
the cursor from the boat are displayed at the  
bottom corner of the window.  
To see stored information about a symbol:  
1
Either move the cursor to the symbol on the  
chart and wait two seconds or use Find to  
move the cursor to a symbol for a port or  
service (see section 3-2-5).  
The chart does not scroll as the boat moves.  
If the cursor reaches the edge of the window,  
the chart will scroll.  
For example, hold down to move the  
cursor to the right side of the window and  
the chart will scroll to the left.  
2
3
A window appears at the bottom of the  
display with some information about the  
symbol.  
3-2-2 Latitude and longitude  
To see more detail about a symbol or a list of  
Latitude and longitude can be displayed in  
the data header. The window is degrees and  
minutes to three decimal places, about 2 m (6  
ft) resolution. Normally the position is the boat’s  
position, and the latitude and longitude has a  
boat symbol to show this:  
ENTER  
associated items for the symbol, press  
:
i
Select an item to display. If there are more  
items than will fit on the window, press  
or to scroll up or down.  
Select a camera icon to display a photo of  
the item. If the photo is too big to fit on  
36° 29.637’ N or S Latitude  
the window, press  
the photo.  
,
,
or to scroll  
175° 09.165’ E or W Longitude  
If the cursor has been moved in the last ten  
seconds, then the position is the cursor’s  
Select Tide Stationto display a tide  
chart for the position (see section 14).  
ESC  
ii Select other items or press  
to the chart.  
to return  
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To see stored information about nearby symbols  
3-2-6 Perspective view  
Perspective view shows the chart from an  
angle instead of from straight above. To turn  
perspective view on or off, press  
Perspectiveto or  
3-2-7 Turn the radar overlay on or off  
If you have a radar installed, you can overlay  
the radar screen on your chart screen. This is  
extremely useful because it can help you to:  
MENU  
press  
follow step 3 above.  
and select Chart info. Then  
MENU  
and set  
3-2-5 Finding a chart symbol  
To find and display a chart symbol:  
MENU  
.
1
2
Press  
and select Find.  
Select the type of symbol: Waypoints,  
Routes, Ports by name, Ports & services, or  
Tide stations.  
interpret the radar image by matching the  
radar targets with charted objects  
3
4
For Ports & services: select the type of  
service to find.  
quickly identify objects that are not on the  
chart, such as other boats  
For Ports by name: press  
,
,
or to  
enter a name or letters contained in the port  
ENTER  
name, then press  
.
The radar overlay is also very useful in  
conditions of reduced visibility, at night, or in  
busy or hazardous waters.  
A list of items is displayed. If there are more  
items than will fit on the window, press or  
to page up and down.  
The range, rotation, mode, and centre position  
of the radar are all adjusted automatically to  
match your chart.  
For Ports by name: to search for a different  
ESC  
port name, press  
. Change the name,  
ENTER  
then press  
.
To turn the radar overlay on or off:  
ENTER  
MENU  
5
Select the item and press  
. The chart  
From the chart window, press  
Radar Overlay option to or  
and set  
window changes to show the item in the  
middle of the window.  
.
An extra menu item will them be displayed to  
control the radar and overlay.  
To see stored information about the item,  
ENTER  
press  
(see section 3-2-4).  
3-3 Distance and bearing calculator  
ENTER  
The distance and bearing calculator can plot  
a course of one or several legs and show the  
bearing and length of each leg, as well as the  
total distance along the course. The completed  
course can be converted into a route.  
Press  
.
4
5
6
To remove the last leg from the course, press  
MENU  
and select Remove.  
Repeat the above two steps to enter the  
whole course.  
To use the distance and bearing calculator:  
To save the new course as a route, press  
MENU  
1
Select the Chart window. Press  
and  
MENU  
and select Save. This also saves any  
select Distance.  
Move the cursor to the start of the first leg. It  
new points on the course as new waypoints,  
with default names. If necessary, edit the  
route later (see section 6-2-2) and edit any  
new waypoints later (see section 6-2-3).  
ESC  
2
does not matter if this point is a waypoint or  
ENTER  
not. Press  
.
3
To add a leg to the course, move the cursor  
to the end of the leg. It does not matter if  
this point is a waypoint or not. The window  
shows the bearing and length of the leg, as  
well as the total distance along the course.  
7
Finally, press  
window.  
to return to the chart  
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3-4 Projected course  
If Projected course is turned on, then the  
Instrument will display the projected position  
based on the course over ground (COG), speed  
and a specified time. To turn Projected course  
on and off and to set the time, see section 19-2.  
A Projected position  
A
B
Boat’s projected course  
Boat position  
B
C
C
3-5 Tracks and tracking  
Tracking records the boat’s position to memory  
at regular intervals, which can be:  
When recording is on and the track becomes  
full then recording continues and the oldest  
points in the track are deleted. The maximum  
length of a track depends on the selected track  
interval: a small interval will give a shorter, more  
detailed track and a long interval will give a  
longer, less detailed track, as shown in these  
examples:  
Time intervals.  
Or distance intervals.  
The track of where the boat has been can be  
displayed on the chart. The Instrument can  
display one track while recording another.  
To work with tracks, see section 19-7.  
The Instrument can store five tracks:  
Time intervals  
Interval  
1 sec  
Track 1  
Track 2, 3, 4 or 5  
minutes  
1.4 hours  
hours  
Track 1 can hold up to 2000 points and is  
intended to record the normal progress of  
the boat.  
33 minutes  
5.5 hours  
33 hours  
8
10 sec  
1 min  
8
Distance intervals  
Tracks 2, 3, 4 and 5 can hold up to 500 points  
each and are intended to record sections to  
be retraced accurately, for example entering  
a river mouth.  
Interval  
Track 1  
Track 2, 3, 4 or 5  
0.01  
1
20  
2,000  
5
500  
10  
20,000  
5,000  
Tip: Record a reference tracks and then use  
the track to help navigate the same trip later.  
For example, record a reference track as you  
leave harbour. Then if you return to harbour and  
visibility is poor, select the chart and navigate  
manually along the reference track back into  
the harbour. Record reference tracks in good  
conditions.  
The track lengths are in the current distance units, for example  
nm.  
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4 Video window  
The video window shows a picture from a  
video device, such as a camera. The video  
window requires a video device to be installed.  
Changing the video picture  
Press to zoom in  
DISPLAY  
To select the video window, press  
select Video.  
and  
Adjusting the video picture color  
MENU  
1
2
Press  
.
Press or to highlight a control, then  
press or to adjust the control.  
Press to zoom out  
3
4
To return the colors to their default settings,  
select Restore defaults.  
ESC  
Press  
.
Press or to move  
the picture sideways  
Press or to move  
the picture up and down  
ESC  
Press  
to fit the  
whole picture in the  
window  
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5 Navigation: Highway window  
A
The highway window shows:  
A Optional data header (see section 2-7-3)  
B Optional compass (see section 2-7-4)  
C Destination waypoint  
B
C
E
D Boat’s plotted course to destination  
E
CDI lines, parallel to the boat’s plotted  
course (see Appendix C, Navigation data,  
CDI). The CDI lines are like a highway over  
the water where the boat will move  
D
D
F
G
F
CDI scale  
G The boat position is at the bottom, centre of  
the window  
The highway window has a bird’s eye view of  
the boat’s course to a destination:  
DISPLAY  
To go to the Highway window, press  
,
!
WARNING  
select More, then select Highway.  
The highway window does not show land,  
dangerous waters or chart symbols.  
6 Navigation: Waypoints  
A waypoint is a position that you can set on the  
Instrument chart, for example a fishing spot or  
a point on a route. The Instrument can have up  
to 3000 waypoints. A waypoint can be created,  
changed or deleted.  
A position.  
A color for the waypoint symbol and name  
on the chart.  
A type:  
Normal: A normal waypoint can be  
A waypoint has:  
navigated to or included in a route.  
A name (up to eight characters).  
Danger: A danger waypoint is a point  
to avoid. If the boat comes within the  
danger radius of a danger waypoint the  
unit can sound an alarm  
An icon showing what kind of waypoint it is.  
The available icons are:  
(see section 19-10).  
A display option:  
Controls how the waypoint is displayed on  
the chart (see section 19-2):  
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6-1 Waypoints window  
DISPLAY  
To go to the waypoints window, press  
,
select More, then select Waypoints.  
The waypoints window is a list of the waypoints  
that have been entered, each with waypoint  
symbol, name, latitude and longitude, distance  
and bearing from the boat, type and display  
option.  
If there are more waypoints than will fit on the  
window, press or to scroll up or down a  
page at a time.  
6-2 Managing waypoints  
Note: Waypoints can also be created when a  
route is created (see section 6-2-1).  
!
WARNING  
Do not create a navigation waypoint on land  
or in dangerous water.  
6-2-2 Moving a waypoint  
Moving a waypoint from the chart window  
1
In the chart window, move the cursor to the  
waypoint to move.  
6-2-1 Creating a new waypoint  
Creating and editing a new waypoint from  
the chart window  
MENU  
2
3
Press  
and select Move.  
Move the cursor to the new position and  
ENTER  
press  
.
1
To create a waypoint at the boat position,  
Moving a waypoint from the waypoints  
window  
ESC  
press  
to switch the chart to centre on  
boat mode.  
To move a waypoint from the waypoints  
window, edit the waypoint (see section 6-2-3)  
and change the latitude and longitude.  
Or, to create a waypoint at a different point,  
move the cursor to that point on the chart.  
ENTER  
2
3
Press  
.
6-2-3 Editing a waypoint  
Editing a waypoint from the chart window  
A new waypoint, with the default name and  
data is created.  
1
2
3
In the chart window, move the cursor to the  
waypoint to edit.  
4
Change the waypoint data if necessary (see  
section 6-2-7).  
When the waypoint data is displayed, press  
Creating a new waypoint from the  
waypoints window  
ENTER  
.
MENU  
Change the waypoint data  
(see section 6-2-7).  
1
2
3
In the waypoints window, press  
and  
select Create.  
A new waypoint, with a default name and  
data, is created at the boat position.  
Change the waypoint data if necessary (see  
section 6-2-7).  
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Editing a waypoint from the waypoints  
window  
Deleting a waypoint from the waypoints  
window  
1
In the waypoints window, press or to  
highlight the waypoint to edit. Press  
1
In the waypoints window, press or to  
highlight the waypoint to delete. Press  
MENU  
MENU  
and select Edit.  
and select Delete.  
2
Change the waypoint data  
(see section 6-2-7).  
2
Select Yesto confirm.  
6-2-6 Deleting all waypoints  
In the waypoints window and press  
MENU  
6-2-4 Displaying a waypoint on the chart  
1
This goes to the chart window, and shows the  
selected waypoint at the centre of the window.  
and select Delete all.  
2
Select Yesto confirm.  
1
In the waypoints window, press or to  
highlight the waypoint to display. Press  
6-2-7 Changing a waypoint’s data  
To change the waypoint data when it is  
displayed in a window:  
MENU  
and select Display.  
MENU  
Or, in the Chart window, press  
Find, then select Waypoints. Select a  
waypoint from the list.  
, select  
1
Select the data to change.  
ENTER  
Press  
.
Use the cursor keys to change the data.  
2
The Instrument switches to the chart  
window, with the selected waypoint at the  
centre of the chart.  
ENTER  
Press  
.
2
3
If necessary, repeat the above step to  
change other data.  
6-2-5 Deleting a waypoint  
Select Save.  
6-2-8 Sort Waypoints  
A waypoint can not be deleted if the boat is  
navigating to it or if the waypoint is used in  
more than one route. A waypoint that is used in  
one route can be deleted.  
To change how the waypoints list is displayed:  
MENU  
1
2
Press  
and select Sort by.  
Select how to display the list:  
Name: In alphabetical order by name.  
Icon: Grouped by icon type.  
!
WARNING  
When a waypoint is deleted from a route,  
check that the changed route does not cross  
land or dangerous waters.  
Distance: In order of distance from the  
boat.  
An arrow at the top of a column indicates how  
the waypoints are sorted.  
Deleting a waypoint from the chart  
window  
6-2-9 Navigating to a waypoint  
See section 3-1-2.  
1
In the chart window, move the cursor to the  
waypoint to delete.  
MENU  
2
3
Press  
and select Delete.  
Select Yesto confirm.  
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7 Navigation: Routes  
A route is a list of waypoints that the boat can  
navigate along. Routes can be created, changed  
and deleted.  
The Instrument can navigate along a route in  
either direction. Waypoints on the route can be  
skipped.  
The Instrument can have up to 25 routes. Each  
route can have up to 50 waypoints.  
Routes are a powerful feature when the  
Instrument is connected to an autopilot,  
allowing the vessel to be automatically guided  
along the route.  
A route can:  
Start and stop at the same waypoint .  
Include waypoints more than once.  
!
WARNING  
Make sure that routes do not cross land or  
dangerous water.  
7-1 Routes window  
The routes window is a list of the routes that  
have been entered, each with route name, start  
waypoint, end waypoint, number of legs and  
total distance.  
DISPLAY  
To go to the routes window, press  
, select  
More, then select Routes.  
If there are more routes than will fit on the  
window, press or to scroll up or down a  
page at a time.  
7-2 Managing routes  
A data box at the bottom left of the window  
shows the route name and total distance. If  
the cursor is near a leg, it shows the length  
and bearing of the leg as well.  
!
WARNING  
After creating or changing a route, display  
the route on the chart and check that it  
does not cross land or dangerous water.  
The legs of a route must start and end at  
waypoints. If a leg does not start or end at  
an existing waypoint then a new waypoint  
will be created automatically (to change the  
new waypoint data, see section 6-2-1).  
7-2-1 Creating a new route  
A. Creating a new route from the chart  
window  
You can not use a Danger waypoint in a  
route.  
While creating the route:  
Press or to change the range; scroll the  
chart by moving the cursor to the edge of  
the chart.  
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MENU  
MENU  
1
2
In the chart window, press  
New route.  
and select  
ii Press  
and select Remove. The  
waypoint is removed from the route, but  
the waypoint is not deleted.  
The route is given a default name:  
Change the name if necessary.  
5
6
7
To start navigating the route  
i
MENU  
i
Press  
and select Start  
ii Select OK.  
To end creating the route  
3
To enter the legs of the route:  
MENU  
i
Press  
and select End  
i
Move the cursor to the start of the route  
ENTER  
and press  
.
To delete the route  
MENU  
ii A waypoint is created with a default  
i
Press  
and select Delete  
ENTER  
name. To save this waypoint press  
to edit the waypoint refer to 6-2-3  
ENTER  
,
ii Select yes to confirm.  
Tip: The distance and bearing calculator can  
also be used to enter a course and save it as a  
route (see section 3-3).  
iii Press  
a dotted leg line is displayed  
from the cursor to the previous waypoint  
B. Creating a new route from the routes  
iv Move the cursor to the end of the first leg  
window  
ENTER  
and press  
.
MENU  
1
2
3
In the routes window, press  
and select  
v
Repeat i to iv until the last waypoint in  
Create.  
the route is placed and saved  
A new route, with a default name and no  
waypoints, is displayed.  
ESC  
vi Press  
to complete the route  
Menu options while creating a route:  
To change the route name:  
1
To add a waypoint to the route  
i
Select the route name at the top of the  
window and press  
MENU  
i
Press  
and select Add.  
ENTER  
.
2
To insert a waypoint in the route by breaking  
one leg into two:  
ii Change the name if necessary.  
ENTER  
iii Press  
.
i
Move the cursor to the leg you want to  
4
To insert a waypoint in the route:  
break.  
i
Select where the waypoint will be:  
MENU  
ii Press  
and select Insert.  
To insert the first waypoint in a new  
route, select Leg 1.  
iii Move the cursor to where the new route  
waypoint will be.  
To insert a waypoint at the end of  
the route, select the unused leg at  
the end of the list of waypoints.  
ENTER  
iv Press  
.
3
4
To move a waypoint in the route:  
i
Move the cursor to the waypoint to  
Otherwise, select the waypoint to  
insert the new waypoint in front of.  
ENTER  
move.  
MENU  
ii Press  
and select Move.  
ii Press  
. A list of waypoints is  
iii Move the cursor to where the waypoint  
displayed. Select the waypoint to use.  
will be.  
As waypoints are inserted, the distance  
and bearing of each leg is shown  
automatically. If the route has more  
waypoints than will fit on the window,  
press or to see them.  
ENTER  
iv Press  
.
To remove a waypoint from the route:  
i
Move the cursor to the waypoint to  
remove from the route.  
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5
To remove a waypoint from the route:  
7-2-3 Displaying a route on the chart  
i
Select the waypoint to remove.  
To view the selected route at the centre of the  
MENU  
window:  
ii Press  
and select Remove.  
1
In the routes window, press or to  
highlight the route to window. Press  
and select Display.  
6
7
8
Repeat this process until the route is finished.  
MENU  
ESC  
Press  
.
Display the route on the chart (see section  
6-2-3) and check that the route does not  
cross land or dangerous water.  
MENU  
Or, in the Chart window, press  
Find, then select Route. Select a route from  
the list.  
, select  
7-2-2 Editing a route  
Editing a route from the chart  
2
The Instrument displays the selected route  
on the chart.  
1
2
3
In the routes window, select the route to  
7-2-4 Deleting a route  
MENU  
edit. Press  
and select Edit on chart.  
1
In the routes window, press or to  
The selected route is displayed on the chart,  
with a circle around the first waypoint.  
MENU  
highlight the route to delete. Press  
select Delete.  
and  
Edit the route as described in section 6-2-1  
A, starting at step 4.  
2
Select Yes to confirm.  
7-2-5 Deleting all routes  
Editing a route from the routes window  
MENU  
1
In the routes window, press  
and select  
1
In the routes window, press or to  
highlight the route to edit. Press  
select Edit.  
Delete all.  
Select Yesto confirm.  
MENU  
and  
2
2
3
The selected route is displayed: the route  
name and a list of the waypoints.  
7-2-6 Navigating a route  
See section 3-1-3.  
Edit the route as described in section 6-2-1 B,  
starting at step 3.  
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8 Satellites  
Differential beacon DGPS  
GPS worldwide navigation  
Differential beacons are land based radio  
transmitters that broadcast correction  
signals that can be received by a special  
receiver on the boat. Differential beacons  
are usually only installed near ports and  
important waterways, and each beacon  
has a limited range. The accuracy of the  
corrected GPS position is typically better  
than 2 to 5 m (6 to 16 ft).  
The US Government operates the GPS system.  
Twenty-four satellites orbit the earth and  
broadcast position and time signals. The  
positions of these satellites are constantly  
changing. The GPS receiver analyses the signals  
from the closest satellites and calculates exactly  
where it is on earth. This is called the GPS  
position.  
The accuracy of the GPS position is typically  
better than 10 m (33 ft) for 95% of the time. A  
GPS antenna can receive signals from the GPS  
satellites when it is almost anywhere on earth.  
GPS receiver  
Northstar GPS units have a sensitive 12-channel  
receiver, which tracks signals from all GPS  
satellites visible above the horizon and uses  
measurements from all satellites more than 5°  
above the horizon to calculate the position.  
DGPS  
A DGPS system uses correction signals to  
remove some of the errors in the GPS position.  
The Instrument can use one of two types of  
DGPS system:  
Each time a GPS receiver is turned on, it  
normally takes about 50 seconds before  
it outputs the first position. Under some  
circumstances it will take up to two minutes or  
longer.  
WAAS and EGNOS DGPS  
WAAS and EGNOS are two satellite based  
DGPS systems. The correction signals are  
broadcast by satellites and are received by  
the Instrument’s standard GPS antenna. The  
accuracy of the corrected GPS position is  
typically better than 5 m (15 ft) for 95% of  
the time.  
WAAS covers all of the USA and most of  
Canada. EGNOS will cover most of Western  
Europe when it becomes operational.  
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8-1 Satellite window  
The satellite window has information about the  
GPS satellites and GPS position.  
DISPLAY  
A Status of GPS antenna, for example  
Acquiring, GPS fix, No GPS. If  
the unit is in Simulate mode it displays  
Simulate(see section 2-6).  
To go to the satellite window, press  
,
select More, then select Satellite.  
B Time and date from GPS satellites. Time is  
local time (UTC [GMT] plus local offset, see  
section 19-4)  
The satellite window shows:  
A
C HDOP: The error in the GPS position caused  
by satellite geometry. A low value indicates  
a more precise fix, a high value a less precise  
fix  
B
E
C
D Signal strengths of up to twelve visible GPS  
satellites. The higher the bar the stronger the  
signal  
G
D
E
F
Boat position  
F
Positions of visible GPS satellites:  
Outer circle is horizon  
Inner circle is 45° elevation  
Centre is directly above  
North is at top of window  
G If the boat is moving, COG is a line from  
centre  
9 Sonar fishfinding: Introduction  
Sonar functions require an optional sonar  
transducer to be installed and set up.  
It also describes Gain and Range and shows  
examples of some of the different sonar  
displays.  
This section explains how to interpret the sonar  
displays, when and why to use the different  
frequencies and how fish are detected and  
displayed.  
9-1 Using the Instrument  
The Instrument uses a sonar transducer  
attached to the hull. The transducer generates  
an ultrasonic pulse (sound that is above the  
hearing range of the human ear), which travels  
down towards the bottom at a speed of about  
4800 ft/sec (1463 m/sec), spreading out into a  
cone shape.  
The depth of the object or bottom is calculated  
by the Instrument by measuring the time taken  
between sending a pulse and receiving the  
echo. When an echo has been returned, the  
next pulse is sent.  
The Instrument converts each echo into an  
electronic signal, displayed as a vertical line of  
pixels.  
When the pulse meets an object, such as a fish  
or the bottom, it is partly reflected back up  
towards the boat as an echo.  
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The most recent echo appears on the extreme  
right of the window, with the older echoes  
being scrolled towards the left, eventually  
disappearing off the window.  
Cruising mode: Use this when on the  
move. The Instrument automatically adjusts  
its settings to compensate for water clarity  
and to display the bottom.  
The scroll speed depends upon the water  
depth and scroll speed setting. See sections  
19-3 and section 9-2, for more information.  
Fishing mode: Use this when fishing. The  
Instrument automatically adjusts its settings  
to compensate for water clarity and to best  
display fish, the bottom and other details.  
The appearance of echoes displayed are  
affected by:  
Manual mode: Use this to fine-tune the  
Instrument settings by hand. Best results  
are often achieved in manual mode, but  
practice and experience are required to  
obtain the optimum settings for different  
conditions.  
The Instrument settings (see sections 19-3,  
9-5 and 9-6)  
Echoes (different fish types, different bottom  
types, wrecks and seaweed; see section 9-2)  
Noise (water clarity and bubbles; see section  
9-2).  
For more information about modes, see  
sections 9-5 and 9-6.  
Cruise, Fishing and Manual Modes  
The Instrument has three sonar operating  
modes:  
!
WARNING  
Use the automatic Cruising or Fishing  
modes when learning to use the Instrument  
or when travelling at speed.  
9-2 Interpreting the display  
The sonar windows do not show a fixed  
distance travelled by the boat; rather, they  
display a history, showing what has passed  
below the boat during a certain period of time.  
A
The history of the sonar signal displayed  
depends the depth of the water and the scroll  
speed setting.  
D
B
In shallow water, the echoes have a short  
distance to travel between the bottom and the  
boat. In deep water, the history moves across  
the window more slowly because the echoes  
take longer to travel between the bottom and  
the boat. For example, when the scroll speed  
is set to Fast, at depths over 1000 ft (300 m)  
it takes about 2 minutes for the data to move  
across the window, whereas at 20 ft (6 m) it  
takes only about 25 seconds.  
C
A School of fish  
B Single fish  
C Hard bottoms such as rock and coral show  
as wide bands  
D Soft bottoms such as mud, weed and sand  
show as narrow bands  
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The scroll speed can be set by the user to  
display either a longer history with less fish  
information or a shorter history with more fish  
details (see section 19-3).  
Location of the fish or object. (The area  
covered by the ultrasonic pulse is a rough  
cone shape and the echoes are strongest in  
the middle.)  
If the boat is anchored, the echoes all come  
from the same area of bottom. This produces a  
flat bottom trace on the window.  
Clarity of water. Particles or air in the water  
reduce the strength of the echo.  
Composition or density of the object or  
bottom.  
The screen shot shows a typical sonar window  
with the Fish symbols turned Off. The sonar  
pulse generated by the Instrument transducer  
travels down through the water, spreading  
outwards in a cone shape. The cone width is  
dependent upon the frequency of the pulse; at  
50 kHz it is approximately 45°, and at 200 kHz it  
is approximately 11°.  
CAUTION  
Planing hulls at speed produce air bubbles  
and turbulent water that bombard the  
transducer. The resulting ultrasonic noise  
may be picked up by the transducer and  
obscure the real echoes.  
The differences in the cone width affect what is  
displayed. (See section 9-3)  
Strength of echoes  
Bottom types  
The colors indicate differences in the strength  
of the echo. The strength varies with several  
factors, such as the:  
Mud, weed and sandy bottoms tend to weaken  
and scatter the sonar pulse, resulting in a weak  
echo. Hard, rocky or coral bottoms reflect the  
pulse, resulting in a strong echo.  
Size of the fish, school of fish or other object.  
Depth of the fish or object.  
Frequency and cone width  
Water Depth ft/m  
Cone width at 50 kHz  
Cone width at 200 kHz  
45˚ cone  
11˚ cone  
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See following for an example of the sonar  
window in such an environment. A double  
bottom trace is shown on the window.  
Shadows  
Shadows are created around areas where  
the ultrasonic beam cannot ‘see’. These areas  
include hollows on the bottom or beside rocks  
and ledges, where the strong echoes returned  
off the rocks obscure the weak echoes of the  
fish and may also create a double bottom trace.  
When looking for fish with the wide angled 50  
kHz frequency, be aware of increased shadows.  
Use the high frequency 200 kHz in areas that  
have rocks and ledges because this frequency  
reduces the shadow effect considerably.  
Example of shadows  
Sonar window of same area  
A
A
B
B
A
A
A Fish is visible on the window  
B Fish is hidden by the strong echoes off the  
bottom and is not shown on the window  
9-3 Single and Dual frequency fishfinding  
Sonar frequencies  
When to use 200 kHz  
The Instrument has two sonar frequencies, 200  
kHz and 50 kHz. To select the sonar frequency  
to use:  
The 200 kHz frequency is especially suitable  
for use in shallow and medium depth water,  
typically less than 500 ft (150 m) and while  
running at speed.  
1
2
Go to a sonar window (see section 9).  
At 200 kHz, the narrow cone reduces any noise  
caused by air bubbles.  
MENU  
Press  
, select Frequencyand select  
200 kHz, 50 kHz, or Mixed.  
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The 200 kHz frequency generates a higher  
definition pulse which produces little shadow  
and returns excellent detail over a small area  
of bottom. Therefore, it gives excellent bottom  
discrimination capability and is particularly  
good at showing individual fish, including  
bottom dwellers.  
When to use 50/200 kHz  
Operating the Instrument at both 50 kHz and  
200 kHz simultaneously on a split window can  
be very useful when operating in shallow to  
medium water, typically less than 500 ft (150  
m), because the 50 kHz section of the window  
shows the general area, while the 200 kHz  
section can be viewed simultaneously for a  
more detailed look at any interesting feature.  
When to use 50 kHz  
The 50 kHz frequency is particularly suitable for  
use in deep water, typically greater than 500 ft  
(150 m).  
To use 50/200 kHz, select the Split 50/200  
window (see section 9-4).  
At 50 kHz, the cone covers an area of water  
about four times wider than the 200 kHz cone  
and penetrates to a greater depth with minimal  
loss of the return signal.  
However, it produces a lower definition display  
with more shadow compared to the 200 kHz  
frequency. This means that a group of small fish,  
for example, could be displayed as a single item,  
while any fish very close to the bottom may not  
be found at all.  
This frequency is useful for getting a deep, wide  
overview of the area so that any areas of interest  
can be identified and then examined in detail  
with the 200 kHz frequency.  
A
B
When to use Mixed  
The Mixed frequency combines the 200 kHz  
and the 50 kHz echoes on one sonar window,  
filling in detailed echoes in the centre of the  
sonar cone.  
A Narrow angle, more detailed 200 kHz cone  
B Wide angle, less detailed 50 kHz cone  
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Comparison of the same fish scenario displayed at different frequencies:  
1 minute ago  
30 seconds ago  
Now  
50 kHz display  
200 kHz display  
200/50 kHz display  
Mixed display  
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9-4 Fish detection and display  
Where to find fish  
Underwater features like reefs, wrecks and rocky  
outcrops attract fish. Use the 50 kHz or 50/200  
kHz frequency window to find these features,  
then look for fish by passing over the feature  
slowly several times using the Zoom window  
(see section 9-2). If there is a current, the fish will  
often be found downstream of the feature.  
A fish arch starts when a fish enters the weak  
edge of the sonar cone, generating a weak  
echo that is displayed as the start of the fish  
arch. As the fish moves closer to the middle of  
the cone, the distance between the transducer  
and the fish reduces and the echo is displayed  
at progressively shallower depths, producing  
a rising shape. When the fish passes directly  
beneath the middle of the cone, the echo  
becomes strongest and thickest. As the fish  
passes out of the middle of the cone the  
reverse happens with a progressively weaker  
and deeper echo.  
When fishing with the Instrument with the  
Fish symbols Off, a weak fuzzy band may  
appear between the bottom trace and surface.  
This might indicate a thermocline - a rapid  
change in water temperature, such as the edge  
of a warm or cold current. The temperature  
difference can form a barrier which the fish  
may not swim through. In fresh water, fish often  
collect around a thermocline.  
There are many reasons why fish arches may  
not be seen. For example:  
Poor transducer installation (see Transom  
Transducers Installation Guide).  
If the boat is anchored then fish will tend to  
show on the window as horizontal lines as  
they swim into and out of the transducer  
sonar beam. Slow speeds in deeper water  
give the best fish arch returns.  
Fish symbols  
The Instrument uses Northstar’s SBN II  
technology to analyze sonar echoes and  
identify which are likely to be fish. The  
Instrument can be set up to display a fish  
symbol and the depth over these echoes (see  
section 19-3, Fish symbols). While SBN II is very  
sophisticated it is not foolproof - there will be  
times when the Instrument will not be able to  
differentiate between fish and large air bubbles  
or rubbish.  
Range is important. It will be much easier  
to see fish arches when using zoom mode  
to concentrate on a particular section of  
water, rather than just displaying everything  
from the surface to the bottom. Zooming  
increases screen resolution and is necessary  
for good fish arches.  
Depending on the strength of a fish signal, the  
Instrument can display a small, medium or large  
symbol (see section 19-3, Fish filter).  
It is difficult to get fish arches in shallow  
water as the transducer sonar beam is very  
narrow near the surface and fish do not stay  
within the beam long enough to display an  
arch. Several fish in shallow water tend to  
display as randomly stacked areas of color.  
To see the maximum amount of information  
from the echoes, turn Fish symbols off. Fish  
appear as arches on the window.  
Fish arches  
Wave motion may result in distorted fish  
arches.  
In good conditions, a fish passing through the  
cone-shaped ultrasonic pulse is displayed as  
a fish arch. The 50 kHz frequency uses a wider  
cone than the 200 kHz frequency. This makes  
the fish arches easier to see.  
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23  
Fun fish symbol  
Normal fish symbol  
Fun symbol + depth  
Fish arch + depth  
9-5 Range  
Range is the vertical depth displayed on the  
Instrument sonar window. For example, if the  
range is 100 m, then the sonar window shows  
depths between 0 and 100 m. The range is  
displayed at the bottom, right corner of a sonar  
window.  
Manual: The Instrument does not adjust the  
range automatically. If the bottom depth is  
below the range, the bottom will not appear  
on the window. Manual range is useful if  
the bottom depth changes rapidly, because  
Auto range will cause the window to change  
range frequently.  
The Instrument has two range modes:  
To set Manual range or to change the range:  
Auto: The Instrument adjusts the range  
automatically so that the bottom of the  
water is always shown at the bottom of the  
window. Auto range is recommended for  
normal operation.  
1
2
Go to a sonar window (see section 9).  
Either press to increase range or press  
to decrease range  
Zoom range and offset  
To set Auto mode:  
The sonar Zoom and Bottom windows can  
show a magnified part of the range (see  
sections 9-2 and 9-3).  
1
2
Go to a sonar window (see section 9).  
MENU  
Press  
, select Rangethen Auto.  
!
WARNING  
Use the Auto range when learning to use  
the Instrument or when travelling at speed.  
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9-6 Gain and threshold  
Gain and threshold settings control the amount  
of detail displayed on a sonar window:  
The Instrument has three operating modes, In  
Cruising and Fishing modes, the Instrument  
automatically adjusts gain and threshold for  
good performance. In manual mode, you can  
hand adjust the settings.  
Gain: The gain of the sonar receiver. The gain  
should be high to display good detail, but if  
the gain is too high then information from the  
strong bottom signal is lost and false echoes  
might be displayed. There is a separate gain  
setting for each sonar frequency, 50 kHz and  
200 kHz.  
To change the mode from the Gain window,  
Select Modeand then select Fishing,  
Cruisingor Manual. When you select  
Manual, the Instrument reverts to your last  
manual settings.  
Threshold: Return echoes less than the  
threshold are ignored. The threshold should  
be as low as possible, but if the threshold is  
too low, unwanted noise will be displayed.  
Threshold is set as a percentage of gain. For  
example, if the threshold is 50 %, then return  
echoes less than 50 % of the maximum signal  
are ignored. There is a separate threshold  
setting for each sonar frequency, 50 kHz and  
200 kHz.  
Changing gain and threshold  
1
In the Gain window, press or to select  
the setting to adjust.  
2
Press or adjust the setting. The  
Instrument changes to Manual mode.  
Tip: Use the A-scope window to help set  
gain or threshold manually (see section  
10-5).  
The gain window  
To display or change the current settings for  
ENTER  
gain, select a sonar window and press  
.
Select Thresholdto display the thresholds.  
Changing mode  
This window is called the gain window.  
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10 Sonar fishfinding: Windows  
DISPLAY  
To show the Sonar window, press  
, then  
Split A-Scope: Sonar history plus echo  
select Sonar.  
strength (see section 10-5)  
There are five kinds of sonar window. To use a  
If the window is split, adjust the split ratio if  
required:  
MENU  
window, press  
then select the type of window to use:  
, select Sonar splits,  
MENU  
1
2
3
Press  
and select Sonar window split.  
No split: Sonar history window at a single or  
mixed frequency (see section 10-1).  
Press or to adjust the ratio.  
ENTER  
Press  
.
Split zoom: Sonar history plus a zoomed  
section (see section 10-2)  
Full screen zoom: (see section 10-2)  
Split bottom: Sonar history plus a bottom  
trace in a zoomed section (see section 10-3)  
Split 50/200: Sonar histories at 50 and 200 kHz  
(see section 10-4)  
10-1 Sonar history window - no split  
A
B
A Optional data header (see section 2-7-3)  
B Optional compass (see section 2-7-4)  
C Depth  
C
D
G
D Color bar  
E
F
Bottom  
Range  
H
E
G Fish symbols with depth  
H Depth line  
The window scrolls from right (most recent  
echoes) to left (oldest echoes).  
F
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10-1-1 Extended history mode  
To review an old sonar echo, use and to  
move back and forward through the sonar  
history. The time since the echoes shown on  
the screen were recorded is displayed at the  
ESC  
bottom of the screen. Press  
the most recent echo.  
to return to  
The digital depth shown is always the current  
depth, even in extended history mode.  
The History Position Bar indicates the age of  
the most resent echo on the screen, and the  
position of the current screen in the recorded  
history.  
History position bar  
10-2 Sonar Zoom and Full Screen Zoom displays  
These windows show a zoomed section of the  
sonar history. The Sonar Zoom display shows  
the sonar history on the right and the zoomed  
section on the left. The Full Screen Zoom  
display shows the zoomed section only.  
A
The zoom bar on the far right shows the area  
of the history that is magnified in the zoom  
section:  
C
B
Press or to adjust the zoom range  
(the range of depths included in the zoom  
section).  
If Bottom lockis on, the zoom depth  
(the depth of the zoom section) is adjusted  
automatically so that the bottom is always  
displayed in the zoom section.  
D
E
A Divider line  
B Depth line marks the centre of the zoomed  
If Bottom lockis off, press or to  
manually adjust the zoom depth. If bottom  
lock is on it will turn off.  
area  
C Zoom bar  
D Zoom section  
Bottom lock  
E
Sonar history  
To turn Bottom lockon or off:  
MENU  
1
2
Press  
and select Bottom lock.  
Select Onor Off. Or if Bottom lockis  
on, pressing or will turn it off.  
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10-3 Sonar Bottom window  
The window shows the sonar history on the  
right and the bottom signal as a flat trace in  
the centre of the zoom section on the left. The  
flat trace make it easy to compare the echo  
strengths shown in the bottom signals. This can  
help to identify the type of bottom and objects  
close to the bottom.  
The zoom bar on the far right shows the area  
of the history that is magnified in the zoom  
section:  
A
Use the or keys to adjust the zoom  
range.  
B
The Instrument calculates the zoom depth  
automatically.  
A Zoomed bottom signal  
It is not necessary to turn Bottom lock on for  
this window.  
B Sonar history  
10-4 Sonar 50/200 window  
The window shows:  
A the 50 kHz sonar history on the left  
B the 200 kHz sonar history on the right.  
Gain can be set independently for each  
frequency (see section 9-6). Range applies to  
both frequencies (see section 9-5).  
A
B
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10-5 Sonar A-Scope window  
ENTER  
4
Press  
to display the Gain window. To  
D
B
adjust gain or threshold for a frequency,  
press or to select the setting to adjust,  
then press or to change the setting.  
E
A
5
6
Set threshold to zero.  
Adjust Gain so the peak of the strong signal  
from the bottom just touches the gain line.  
C
7
Adjust threshold so that it is just to the right  
of the noise.  
ESC  
8
9
Press  
to close the gain window.  
If required, repeat these steps to adjust gain  
and threshold for the other frequency.  
The window shows the sonar history on the  
left and the A-Scope window on the right. The  
A-Scope shows:  
Note: Setting the gain higher will display more  
detail from weak echoes, like fish, but will loose  
detail from the strong echo from the bottom.  
A, B, C, The strengths of echoes being received  
now from different depths - the longer the  
horizontal line the stronger the signal:  
Fish recognition  
The echo strengths shown on the A-scope  
can be useful in recognizing the type of fish.  
Different species of fish have different sizes  
and shapes of swim bladders. The air in the  
swim bladder reflects the ultrasonic pulse, so  
the strength of the echo varies between fish  
species according to the size and shape of the  
swim bladder.  
A Unwanted noise echoes.  
B Echoes from fish and the bottom  
C The strongest echo, usually from the bottom  
D A vertical line showing the threshold, the  
weakest echo to display on the sonar history  
E
A vertical line showing the gain setting;  
echoes above this strength will display as  
the maximum signal strength  
When catching fish from a school, note the  
species and the strength of the echo that  
it returns on the A-scope. Then, when that  
particular echo is seen again, it is likely to be the  
same fish species.  
Use the A-Scope while adjusting the gain and  
threshold settings manually (see section 9-6).  
Setting gain and threshold  
Bottom type  
The shape of the echo strengths in the A-Scope  
can help you to recognise the type of bottom.  
It is convenient to use the A-scope window  
when adjusting gain and threshold manually.  
Follow this procedure to adjust gain and  
threshold for normal circumstances:  
1
Switch to a sonar window (see section 9). If  
necessary, press or to adjust range so  
that the bottom is displayed.  
2
If necessary, select the sonar frequency to  
MENU  
adjust the settings for. Press  
, select  
Frequencyand select 200 kHzor 50  
kHz.  
Press  
MENU  
3
, select Sonar splits then select  
Split A-scope.  
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11 Gauges window  
The Gauges window shows boat data, such  
Selecting a Gauges layout  
as water speed, as analog gauges. To select  
The Gauges window can show one of four  
gauge layouts. To select a layout from the  
DISPLAY  
the Gauges window, press  
, select More,  
then select Gauges. Before using the Gauges  
window, set Speed range, Max RPM and Max  
fuel flow (see section 19-13).  
MENU  
Gauges window, press  
select a layout.  
, select Layout and  
Changing a gauge layout  
You can change the data displayed on each  
gauge in a layout.  
1
2
3
Select the layout to change (see above).  
MENU  
Press  
and select Gauge setup.  
ENTER  
Highlight the gauge to change. Press  
and select the data to display in the gauge.  
4
5
Repeat the above step to change other  
gauges.  
ESC  
Press  
.
12 Data window  
The data window has large numeric data fields  
and a graph of depth and water temperature if  
DISPLAY  
available. To go to the data window, press  
,
select More, then select Data.  
To select what data is displayed:  
MENU  
1
2
Press  
and select Data setup.  
Change a data field:  
i
Press the cursor keys to highlight the  
field.  
ENTER  
ii Press  
items.  
to display a menu of data  
iii Select a data item that is available on  
your system or select Noneto leave the  
field empty.  
3
4
Repeat the above step to set the other data  
fields.  
ESC  
Press  
.
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13 Fuel functions and display  
The Fuel functions require optional petrol/gasoline or SmartCraft fuel sensors to be installed and set  
up.  
13-1 What the fuel computer does  
Each engine has a flow sensor installed to  
!
WARNING  
measure the engine’s fuel flow.  
The M121/M84 use these flows, together with  
boat speed and engine RPM if available to  
estimate the fuel remaining in the tank(s), fuel  
used, range and fuel economy. This data is  
displayed on the fuel display (see section 13-2).  
To ensure the fuel data is accurate:  
When you add or remove fuel from a  
tank, tell the M121/M84 (see section 13-3)  
If the boat has petrol/gasoline sensors,  
calibrate them during installation or if  
the fuel readings seem inaccurate (see  
section 13-7)  
You can:  
display the fuel used during a trip  
(see section 13-2)  
Choose an appropriate type of boat  
speed sensor to calculate economy,  
range and the fuel consumption curve  
(see section 13-5)  
set low fuel alarms (see section 13-4)  
make fuel consumption curves - graphs  
of fuel consumption and boat speed as a  
function of engine RPM - to monitor and  
optimize boat performance.  
If the boat uses a paddlewheel sensor  
to measure speed, calibrate it during  
installation or if the speed readings seem  
inaccurate.  
(see section 13-6)  
13-2 Fuel display  
DISPLAY  
Fuel display  
To go to the Fuel display, press  
, select  
More, then select Fuel.  
The display differs according to the number of  
engines and tanks. If engine RPM is available  
and if you have made and selected a Fuel  
Consumption Curve (see section 13-6), press  
to switch between a Summary or a Fuel curve  
display.  
The Fuel display shows  
Speed  
To select a boat speed sensor, see section 13-5-1.  
RPM (if available)  
If engine RPM is not available, the display shows  
depth.  
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Remaining  
Fuel flow  
The fuel remaining in the tank(s) is shown as a  
vertical gauge on the right of the display. The  
height of the yellow bar(s) show how much fuel  
remains in the tank(s). If you have set a low fuel  
alarm (see section 13-4), a red bar shows the  
level at which the alarm will trigger. If there are  
two tanks, the left bar shows the port tank, the  
right bar shows the starboard tank.  
The fuel flow for the engine(s). On a multi  
engine boat, the data for the port engine is on  
the left of the display. Use the flows to check  
the load of each engine.  
Range  
The estimated boat range at the current fuel  
flow. The value can depend on the type of  
speed sensor (see section 13-5).  
Used  
The fuel used during a trip. On a multi-engine  
boat, the data for the port engine is on the left  
of the display.  
When you want to start measuring how much  
fuel is used, go to the Fuel display and:  
Economy  
The distance travelled per unit of fuel used. The  
value can depend on the type of speed sensor  
(see section 13-5). The larger the value, the  
better the fuel economy. Adjust the throttle and  
trim to achieve the best economy.  
MENU  
In a single engine boat, press  
and  
select Clear used.  
In a multi-engine boat, the fuel used by  
each engine and the total fuel used are  
Fuel consumption curve  
A graph of fuel consumption and boat speed  
as a function of engine RPM. Use the curve to  
monitor and optimize boat performance (see  
section 13-6).  
MENU  
shown. Press  
and select:  
, select Clear used  
Portor Starboardto clear the fuel used  
by one engine  
Both to clear the total fuel used.  
13-3 When you add or remove fuel  
When you add or remove fuel, you must tell  
the M121/M84, otherwise the fuel data will be  
meaningless.  
B When you part fill a tank  
1
2
3
4
Add fuel to a tank and write down how  
much fuel you add.  
A When you completely fill a tank  
MENU  
From the Fuel display, press  
and select  
MENU  
Go to the fuel display and press  
Then:  
.
Add fuel.  
On a multi-tank boat, select the tank that  
you have added fuel to.  
On a single-tank boat, select Fill tank.  
Change the number to the amount of fuel  
that you added.  
On a multi-tank boat, select Fill tank,  
then select the tank you have filled.  
Note: If you follow procedure B every time you  
add fuel, then a small error will accumulate,  
because it is hard to measure exactly how much  
fuel you add. To avoid this, completely fill the  
tank and follow procedure A about every tenth  
time you add fuel.  
Note: Underfloor fuel tanks are often difficult to  
refill to the same level twice, due to air pockets.  
With underfloor fuel tanks:  
Trim the boat to the same angle in the water  
each time you follow procedure A.  
Mostly use procedure B below when adding  
fuel, but completely fill the tank and follow  
procedure A about every tenth time you add  
fuel.  
C When you remove fuel  
1. Before removing fuel, go to the Fuel display,  
MENU  
press  
and select Set remaining.  
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2. On a multi-tank boat, select the tank that  
you are removing fuel from.  
6. Change the number on the Set Remaining  
menu to the amount of fuel that you  
calculated was now in the tank.  
3. Write down the value of Remaining for the  
tank; this is the amount of fuel originally in  
the tank.  
ENTER  
7. Press  
Note: You can also use this procedure when  
you add fuel to a tank. In this case, add the fuel  
you have added to the amount of fuel originally  
in the tank to calculate the amount of fuel now  
in the tank.  
4. Remove fuel from the tank and write down  
how much fuel you remove.  
5. Subtract the amount of fuel you removed  
from the amount of fuel originally in the tank  
to calculate the amount of fuel now in the  
tank.  
13-4 Low fuel alarm  
To set a low fuel alarm for a tank:  
When a low fuel alarm is set, the alarm’s fuel  
level is shown on the fuel display tank levels as  
a red bar. The alarm can also be set using the  
Alarms setup menu (see section 19-10)  
MENU  
1
2
3
Press  
twice, select Fuel,then select  
Setup tanks.  
On a multi-tank boat, select the tank to set  
the alarm for.  
Select Tank alarmand enter a fuel level  
to trigger the low fuel alarm; or enter zero to  
disable the alarm.  
13-5 Boat speed sensors  
To select an optional speed sensor  
13-5-1 Selecting a boat speed sensor  
MENU  
1
Press  
twice, select Fuel,then select  
The fuel calculations can use boat speeds from  
the GPS, or from a paddlewheel sensor or pitot  
sensor if these optional sensors are installed:  
Speed source.  
2
To use a paddlewheel or pitot sensor, select  
Water speed, otherwise select Ground  
speedto use GPS speed.  
Paddlewheel and pitot sensors measure  
the speed through the water; GPS speed is  
speed over ground; these sensors can give  
different values for Range, Economy and  
the fuel consumption curves (see section  
13-5-2).  
3
i
If you selected Water speed and you have  
both a paddlewheel sensor and a pitot  
sensor:  
ESC  
Press  
, select SmartCraftand select  
A pitot sensor is more accurate than a  
paddlewheel sensor at high speeds but is  
not accurate at low speeds. A paddlewheel  
sensor is more accurate than a pitot sensor  
at low speeds.  
Speed type  
ii Select Paddlewheelor Pitot.  
Tip: You can select a different speed sensor  
during a trip.  
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Water speed is better for measuring the boat’s  
potential performance, Ground speed is better  
for going to a destination because it takes  
currents into account. To select a speed sensor,  
see section 13-5-1.  
13-5-2 Water speed and ground speed  
A paddlewheel sensor and a pitot sensor  
measure water speed, the boat speed through  
the water. A GPS measures ground speed, the  
boat speed over the bottom of the water. If  
there is a current, then these speeds will be  
different, and the log, trip log, economy and  
range will be different, as shown below.  
When the current is from ahead, ground speed is less than water speed  
Water speed 10 knots  
Water speed 10 knots  
Current 4 knots  
Gives a ground speed of 6 knots  
Gives a ground speed  
of about 8 knots  
Current 4 knots at 45º  
For this example:  
If the boat travels for one hour, uses 3 gallons of fuel per hour and has 50 gallons of  
fuel left:  
Speed  
Log  
Economy  
3.3 nm / gal  
2.0 nm / gal  
Range  
165 nm  
100 nm  
Using water speed:  
10 knots  
10 nm  
6 nm  
Using ground speed: 6 knots  
When the current is from behind, ground speed is more than water speed  
Water speed 10 knots  
Current 4  
knots at 45º  
Current  
4 knots  
Water speed 10 knots  
Gives a ground speed of 14 knots  
For this example:  
Gives a ground speed of about 13 knots  
If the boat travels for one hour, uses 3 gallons of fuel and has 50 gallons of fuel left:  
Speed  
Log  
Economy  
3.3 nm / gal  
4.7 nm / gal  
Range  
165 nm  
235 nm  
Using water speed:  
10 knots  
10 nm  
14 nm  
Using ground speed: 14 knots  
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13-6 Fuel consumption curves  
A fuel consumption curve shows fuel  
consumption (fuel used per unit of distance  
travelled) and boat speed as a function of  
engine RPM. Fuel consumption curves require  
engine RPM, which requires SmartCraft to  
be installed. Fuel consumption curves are  
powerful tools for assessing boat performance  
in different conditions and for helping you  
to run at the most economical speed for the  
conditions.  
6
7
The M121/M84 then asks you to set the  
minimum RPM. Set the throttle to idle; on a  
multi engine boat set all engines to about  
the same idle RPM.  
Now, do not change the engine speed.  
Wait for about 60 seconds for the boat to  
ENTER  
stabilise, then press  
. Wait while the fuel  
computer records the data.  
The M121/M84 then asks you to set the  
throttle to achieve a target RPM. On a multi  
engine boat set all engines to about the  
target RPM. When the engine RPMs are  
correct, the Target RPM box will turn green.  
Now, do not change the engine speed.  
13-6-1 Making a fuel consumption curve  
To make a fuel consumption curve you will  
need to run the boat in a straight line for about  
15 minutes using the engine’s full RPM range.  
For your first curve, choose a calm day with  
light wind and little current; have a typical load  
and a freshly cleaned hull. Later, you can make  
fuel consumption curves for different boat,  
weather or sea conditions. Compare these  
with your first curve to see how your boat’s  
performance changes with conditions.  
Making a curve  
1
2
Start running the boat in a straight line.  
Choose a speed source for the curve (see  
section 13-5-1). Normally choose Water  
speed to measure the boat’s potential  
performance.  
MENU  
Wait for about 60 seconds for the boat to  
3
4
Press  
twice, then select Fuel.  
stabilise, ensuring the Target RPM box stays  
Select Fuel consumption curve,  
ENTER  
green. Then press  
. Wait while the fuel  
then select New.  
computer records the data.  
5
Enter the comfortable maximum RPM you  
know you can achieve for the engine rather  
than the maker’s value.  
8
The M121/M84 repeats the above step to  
record data up to the maximum RPM. Then  
the M121/M84 asks if you want to save the  
curve. Select Yes. The fuel computer asks for  
a name for the curve. Change the default  
ENTER  
name if required. Then press  
. The  
M121/M84 stores the new curve.  
Note To interrupt making the curve at any time,  
ENTER  
press  
.
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Information in a curve  
13-6-2 Managing fuel consumption curves  
A RPM of the boat now. For a twin engine  
boat, the RPM is the average of the two  
RPMs.  
Renaming a curve  
MENU  
1
2
Press  
twice, then select Fuel.  
Select Fuel consumption curve.  
Select Name and select the name of the  
curve to rename.  
B Red curve: boat speeds at different  
RPMs recorded when you made this fuel  
consumption curve.  
ENTER  
3
Select Rename and press  
. Change  
C Red marker: the boat speed now. This  
marker is below the red curve, showing that  
the boat speed now at this RPM is less than  
when you recorded the curve.  
the name.  
13-6-3 Using fuel consumption curves  
Deleting a curve  
MENU  
1
2
Press  
twice, then select Fuel.  
D Blue curve: fuel consumption at different  
RPMs recorded when you made this fuel  
consumption curve.  
Select Fuel consumption curve.  
Select Name and select the name of the  
curve to delete.  
E
Blue marker: the fuel consumption now. This  
marker is below the blue curve, showing  
that the fuel consumption now at this RPM is  
better than when you recorded the curve.  
3
Select Delete.  
Selecting a curve  
1
You must make a fuel consumption curve  
before you can use it (see section 13-6-1).  
MENU  
F
If the blue curve has a dip, then running the  
boat at this RPM will give the best speed for  
the least fuel consumption.  
2
On the Fuel display, press  
, select Fuel  
consumption curve and select the name of  
the curve to use.  
3
On the fuel display, press if necessary  
to select Fuel curve and display the fuel  
consumption curve.  
F
E
D
Note  
B
C
a
On a multi engine boat, keep the RPM of all  
engines similar while using a curve.  
b
The shape of the curve depends on the type  
of speed sensor you selected when making  
the curve (see sections 13-5-1 and 13-5).  
A
Using a curve  
Compare your boat’s performance now, at the  
current RPMs, with the boat’s performance  
when you made the curve. You can compare  
your boat’s performance now with a curve  
made under ideal conditions or with a curve  
made under similar conditions.  
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13-7 Calibration  
Calibrate petrol/gasoline fuel flow sensors  
during installation, or if the fuel readings seem  
inaccurate and the other troubleshooting  
suggestions do not help (see Appendix B  
troubleshooting).  
To calibrate the sensor(s):  
1
2
Record the level of the fuel in the tank(s).  
Connect the portable tank(s) to the engine  
through the fuel sensor(s).  
3
4
Run the engine at normal cruising speed  
until at least 4 gallons (15 litres) of fuel has  
been used per engine.  
Note  
SmartCraft fuel sensors are factory calibrated  
and should never need recalibrating.  
Check the actual amount of fuel used per  
engine by refilling the portable tank(s) to the  
original level and noting the reading(s) of  
the fuel dispenser’s gauge.  
On a multi engine boat, calibrate each  
engine’s sensor. This can be done at the  
same time with a portable tank for each  
engine or at different times using one  
portable tank.  
MENU  
5
6
Press  
twice, select Fuel,then select  
Setup engines.  
Calibrating a sensor requires accurate  
measurement of the fuel consumption.  
This is best done using a small portable tank.  
At least 4 gallons (15 litres) of fuel should be  
used to ensure an accurate calibration.  
On a single engine boat, select Calibrate  
and change the displayed value to be equal  
to the reading of the fuel dispenser’s gauge,  
ENTER  
then press  
.
On a multi-engine boat select the engine.  
It is often very difficult to fill underfloor tanks  
to the same level twice due to air pockets, so  
the more fuel used, the more accurate the  
calibration.  
Select Calibrateand change the  
displayed value to be equal to the reading of  
ENTER  
the fuel dispenser’s gauge, then press  
Repeat for the other engines.  
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14 Tides window  
MENU  
The tides window is available on Chart cards.  
The tides window shows tide information at a  
tide station for the selected date.  
1
From the chart window, press  
and  
select Find.  
Select Tide stations.  
2
3
A list of tide stations are displayed. Select  
the tide station to display. The chart redraws  
with the tide station centred.  
MENU  
CAUTION  
The tides window requires the local time  
offset to be set to work correctly (see  
section 19-14)  
4
5
Press  
and select Chart info.  
Select Tide height.  
Choosing the date of the tide chart  
MENU  
1
2
From the tides window, press  
.
To show the tides window for the tide station  
DISPLAY  
Select Today, Next dayor Prev day.  
To choose a different date from these, select  
nearest to the boat, press  
then select Tides.  
, select More,  
Set date, edit the date,  
To go to the tides window for any tide station:  
ENTER  
press  
.
The tides window shows data for the chosen date  
A
N
B
K
E
G
D
F
D
M
L
C
I
H
J
A Tide station name and distance from boat  
B Current time and chosen date for display  
C Tide chart  
J
Time of cursor and tide height at that time  
K Data for the chosen date  
L
Tide height cursor, a horizontal dotted line.  
Press or to move cursor up and down.  
D Night  
M Height of cursor on the tide chart  
E
F
Dawn  
Day  
N Moon phase for moon at the current time  
on the chosen date  
G Dusk  
H Tide height  
I
Time cursor, a vertical dotted line. Press or  
to move cursor sideways  
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15 User card window  
A user card is an optional plug-in card that can  
store data files (see section 1-3). There are three  
types of files: waypoints, routes or a track.  
DISPLAY  
Loading data from the user card to the  
Instrument  
This loads one file from the user card to the  
To go to the user card window, press  
,
Instrument:  
select More, then select User card.  
CAUTION  
1
Before using a user card, remove any  
chart card and plug the user card in.  
When you have finished with the user  
card, remove the user card and replace  
the chart card (see section 1-3).  
The user card window has:  
File list  
A list of the files on any user card in the  
Instrument. If there are more files than will fit  
on the window, press or to scroll up or  
down a page at a time.  
A waypoints file: The new waypoints are  
added to any existing waypoints in the  
Instrument. If a new waypoint has the same  
name as an existing waypoint but has  
different data, the Instrument displays both  
waypoints. Select:  
Waypoints, Routes  
The number of waypoints and routes currently  
in the Instrument.  
Track 1 to Track 5  
Skip: Do not load the new waypoint.  
The number of points in tracks 1 to 5 currently  
in the Instrument.  
Replace: Load the new waypoint and  
replace the existing one.  
Note:  
Skip all: Do not load any new  
waypoints which have the same names  
as existing waypoints.  
1
To save Instrument data onto the user card,  
use the Save command (see below).  
2
Data stored on the user card and shown on  
the file list is not available to be used by the  
Instrument until loaded into the Instrument  
with the LOAD command (see below).  
Rplc all: Load all new waypoints  
which have the same names as existing  
waypoints; the new waypoints replace  
the existing waypoints.  
Saving data to the user card  
A routes file: The new routes are added  
to any existing routes in the Instrument.  
If a new route has the same name as an  
existing route but has different data then the  
Instrument asks which route to keep.  
This saves all the Instrument’s waypoints, all the  
Instrument’s routes or one of the Instrument’s  
tracks to one file on the user card.  
MENU  
1
2
3
Press  
and select Save.  
Select Waypts, Routesor Tracks.  
A track file: The new track will replace the  
existing track in the Instrument.  
For Tracks, select the track number to  
save.  
4
The new file is created. Change the name  
if required. The new file appears in the  
file list.  
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To load a file to the Instrument:  
Formatting the user card  
1
2
Select the file to load.  
Formatting prepares a user card for use. Format  
the card if there is an error message saying that  
the card is not formatted. Any data files on the  
card are deleted.  
MENU  
Press  
and select Load.  
Deleting a file from the user card  
1
Select the file to delete.  
MENU  
1
2
3
Press  
and select Card.  
MENU  
2
3
Press  
and select Delete.  
Select Format.  
Select Yesto confirm.  
Select Yes to confirm.  
Rereading the file information  
This reads the file names from the user card and  
displays them. Reading does not load any file  
data into the Instrument. You should not need  
to do this.  
!
WARNING  
Do not format a chart card.  
MENU  
1
2
Press  
and select Card.  
Sorting the file names  
This sorts the displayed file names.  
MENU  
Select Read.  
1
2
Press  
and select Sort.  
Select sort by Name, Typeor Time.  
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16 AIS  
AIS is short for Automatic Identification System.  
The International Convention for Safety of  
Life At Sea (SOLAS) requires all vessels greater  
than 300 tons and all passenger vessels to be  
equipped with AIS Transponders. All vessels  
equipped with AIS permanently broadcast  
via one or more of the two dedicated VHF  
channels. This transmission may include  
information about the vessels MMSI-number,  
its call sign, name, position, course, heading,  
speed, rate of turn and type of vessel.  
area are shown on the chart when this feature  
is enabled.  
The following AIS receivers are supported by  
this unit:  
Comar SLR200 (external GPS).  
Weatherdock Two Channel AIS Receiver  
“EASY AIS”, Part No. 5-A-013 (external GPS).  
NASA Marine AIS Engine 2 channel Receiver  
(external GPS).  
Other AIS receivers may work but have not  
been tested with this unit.  
This unit can receive and display AIS  
information when connected to an AIS receiver.  
Available AIS vessels transmitting in the local  
To enable AIS from the system menu check the  
AIS box. (see section 16-3)  
16-1 Viewing AIS Vessels  
A typical AIS window shows:  
E
B
A
C
D
A AIS Vessel  
B Dangerous Vessel  
C Projected Course  
D Data Box  
E
Range Rings  
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When the cursor is placed over an AIS vessel for  
at least two seconds, a data box appears at the  
bottom of the window with information about  
the AIS vessel.  
For complete AIS information on the AIS vessel  
place the cursor over an AIS vessel for at least  
two seconds and press  
.
Press either  
information.  
or  
to clear the  
16-2 Dangerous Vessels  
The M121/M84 calculates the time of closest  
point of approach (TCPA) and closest point of  
approach (CPA) for each AIS vessel.  
A dangerous vessel is indicated on the chart by  
a red circle around the icon.  
TCPA 15 min  
This is used to determine potential dangerous  
vessels. If the TCPA and the CPA is below  
the trigger values then it will be considered  
dangerous. (See section 19-8 for setting the  
dangerous vessel alarm)  
CPA 0.5 nm  
16-3 AIS Windows  
To go to the AIS windows, press  
, select  
Vessels  
More, select AIS, then press or to select  
one of the two windows: Vessels or Safety msgs  
(rx).  
This is a sorted list of vessels currently being  
received by the AIS receiver. The maximum  
number of vessels that the system will support  
is 250. Once maximum is reached, vessels  
furthest away from the current location will be  
replaced. A vessel will be removed from the list  
if no information is received within 6 minutes  
from the last message.  
If there are more items than will fit on the  
window, press  
or  
to see the others.  
Displaying an AIS vessel on the chart  
1
Press or to select a vessel.  
2
Press  
and select Display. The  
Instrument switches to chart window, with  
the selected vessel position in the middle.  
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Displaying Full AIS Details  
Safety msgs (rx)  
1
Press or to select a vessel.  
Safety msgs (rx) are broadcasted messages  
received by the AIS receiver. This window  
displays the date and time of message  
2
Press  
and select More Infoor press  
.
received, MMSI of AIS vessel that broadcasted  
the message, and the message itself. Safety  
msgs (rx) list will store up to 10 messages. The  
oldest message is replaced when the list is full.  
This window displays all information for  
the selected AIS vessel provided by the AIS  
receiver.  
Sorting Vessels  
Press  
, select Sort and select one of  
the options.  
This sorts the list based on the chosen  
category.  
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17 DSC/Buddy track windows  
DISPLAY  
Buddy track requires an optional Northstar DSC  
VHF radio to be installed. Buddy track tracks  
other boats which have DSC radios connected  
to their GPS receivers by NavBus and are in VHF  
range. For information on setting up and using  
the VHF radio for buddy track, see the radio’s  
operation manual.  
To go to the DSC windows, press  
, select  
More, then press or to select one of the  
three windows: Distress, Poll or Buddy track.  
If there are more items than will fit on the  
window, press or to see the others.  
17-1 The windows  
Distress  
Boats that have sent DSC distress  
messages and their positions.  
Poll  
Buddy track  
Buddy boats from your DSC radio.  
The radio regularly calls the boats  
and updates their positions.  
Boats you have manually polled  
on the VHF radio, and their posi-  
tion at that time.  
When your DSC radio receives a distress  
message, the Instrument creates a distress  
waypoint at the boat position. Distress  
waypoints have default names like DSTRSS01.  
The Instrument displays a Distress warning.  
Select:  
OK to return to what you were doing.  
Display to switch to Chart and display the  
position of the boat sending the distress  
message.  
Polled boats: The position is where the boat  
was when you last polled the boat.  
Boat positions  
The boat positions on the Instrument can differ  
Buddy track: The position is where the boat  
was when your radio last polled the boat.  
from the true boat positions:  
Distress: The position is the distress  
waypoint, which is where the boat was  
when it sent the distress message.  
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17-2 Using the windows  
Displaying a boat on the chart  
1
Press or to select a boat.  
B
A
MENU  
2
Press  
and select Display. The  
Instrument switches to chart window, with  
the selected boat position in the middle (see  
Boat positions above).  
Going to a boat  
1
Press or to select a boat.  
MENU  
2
Press  
and select Goto. The Instrument  
starts navigating to the boat’s position (see  
Boat positions 17-1).  
Creating a waypoint  
On a chart window:  
Polled and buddy track boats are not waypoints.  
To create a waypoint at the position of a polled  
boat (see Boat positions above):  
A Distress boats are distress waypoints  
B Buddy track boats are buddy symbols  
1
2
Press or to select a boat.  
Deleting a boat  
At the Distress or Poll windows:  
MENU  
Press  
and select Create  
waypoint. Edit the waypoint data if  
1
2
Press or to select a boat.  
required (see section 6-2-7).  
MENU  
Press  
and select Delete. The boat is  
Editing a waypoint  
deleted from that window. Delete any boat  
waypoint manually (see section 6-2-5).  
A distress message creates a waypoint for the  
boat or you can create a waypoint at a polled  
boat’s position. To change the data of these  
waypoints:  
Buddy track boats automatically disappear from  
the Buddy track window when your DSC radio  
can not pick up their signal.  
1
2
Press or to select a boat.  
Deleting all boats  
At the Distress or Poll windows:  
MENU  
Press  
and select Edit waypoint.  
Edit the waypoint data if required (see  
section 6-2-7).  
1
2
Press or to select a boat.  
MENU  
Press  
and select Delete all. All  
boats are deleted from that window and any  
boat waypoints are deleted.  
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18 Radar  
Radar is the Radio Detection And Ranging  
system. Radar functions require an optional  
Northstar radar system to be installed. Three  
radar systems are available; 2 kW, 4 kW, or  
6 kW.  
The scanner rotates through 360° so the radar  
window shows all of the area around your boat  
within the range of the scanner, producing a  
map-like display called the PPI (Plan Position  
Indicator).  
When the radar is operating, the scanner  
transmits powerful microwave radio pulses  
which are reflected back from any solid objects  
such as land masses or other boats. These  
objects are called targets and are shown on the  
radar window.  
Typically, your boat is in the centre of the  
radar window with concentric range rings  
surrounding it. The range rings help you to  
quickly estimate the distance to various targets.  
If you prefer to view the radar overlaid on the  
chart screen see section 3-2-7.  
18-1 Radar window  
A
B
C
K
L
I
J
M
D
H
G
E
F
The radar window shows:  
G Compass ring  
A Distance between each range ring (in this  
H Range ring  
example, 1/8 nautical mile)  
I
North line (blue)  
B Range of radar (in this example, shown in  
J
Heading line (white)  
large digits)  
K The bearing (in Relative, True, or Magnetic  
C Radar rotation (in this example, North Up)  
mode)  
D Radar motion mode (in this example,  
L
Echo Expansion setting  
Relative Mode)  
M Interference Rejection setting  
E
F
Cursor  
Distance and bearing to the cursor position  
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18-2 Radar modes  
There are four radar modes:  
Standby. The radar is on and is warmed up. It  
is ready to start transmitting immediately.  
Disabled. This saves on power consumption  
and magnetron usage. If the radar is  
disabled, it has to warm up and enter  
standby mode before it can start  
transmitting.  
Transmitting. The radar is actively sending  
and receiving microwave radio pulses. An  
open array will be rotating.  
If you want to save on power but be able to  
start transmitting immediately, use standby  
mode.  
Warming. The radar on and is warming up.  
This can take up to 90 seconds, depending  
on your scanner type.  
18-3 Enabling the radar functionality  
When the radar is enabled, it will turn on, warm  
up, and enter standby mode. The different radar  
modes are explained in Section 18-2.  
3
4
The radar immediately turns on and enters  
warm-up mode. A message shows how long  
this will take.  
To enable the radar functionality:  
When the warm-up period is complete, the  
radar enters standby mode and is ready to  
transmit. To start the radar transmitting, see  
Section 18-4.  
MENU  
1
Press  
twice to display the Setup menu,  
then select System.  
2
Set Radar to  
.
18-4 Selecting standby mode or transmit mode  
MENU  
You can quickly change between these two  
modes.  
1. From the radar window, press  
and set  
the Transmit option to (transmit mode) or  
(standby mode).  
18-5 Disabling the radar functionality  
MENU  
3
4
A warning message appears. If you are  
sure that you want to disable the radar  
functionality, select Yes.  
1
2
Press  
twice to display the Setup menu,  
then select System.  
Set Radar to  
.
The radar enters disabled mode  
immediately.  
18-6 Adjusting the quality of the radar window  
Common problems that can degrade the  
quality of the radar window include:  
shadows (blind spots)  
multiple echoes off the same object  
incorrect threshold setting  
sea clutter  
rain clutter  
If the radar is installed at a suitable height and  
in a suitable location on your boat, side lobe  
patterns and shadows (blind spots) caused  
by obstructions such as funnels or masts will  
be minimized. If you’re having problems with  
false echoes (sometimes called ghost  
echoes) and background noise  
side lobe patterns (false echoes that appear  
as an arc or a broken arc)  
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these, you may need to relocate the radar.  
Consult the Installation Guide for your Northstar  
radar or talk to your dealer or installer.  
18-6-2 Changing the gain level  
Use the radar gain level to adjust the sensitivity  
of the radar receiver. Ideally, the radar gain level  
should be set so that background noise is just  
visible on the radar window.  
Multiple echoes off the same object are  
most likely to occur when you are close to a  
large target and are usually only a temporary  
nuisance.  
If the radar gain level is too low, weak echoes  
won’t be shown. If the radar gain level is too  
high, strong echoes will be difficult to see  
amongst the large amount of background  
noise.  
You can adjust the radar to reduce the effects  
of sea clutter, rain clutter, and interference from  
other radars. You can also change the gain  
mode setting and the gain level setting to help  
reduce false echoes.  
(If the radar Gain Mode is set to Auto and you  
adjust the gain level manually, the Gain Mode is  
changed to Manual.)  
MENU  
1
From the radar window, press  
then  
select Presentation.  
To change the radar gain level:  
ENTER  
2
Select Adjust Radarand press  
.
MENU  
1
From the radar window, press  
then  
select Adjust Radar.  
18-6-1 Changing the gain mode  
Use the radar gain mode to specify whether  
2
Select Gain Levelthen use and  
to decrease or increase the setting.  
18-6-3 Changing the sea clutter mode  
(Manual mode)  
Sea clutter usually appears as confusing,  
random signals close to your boat on the radar  
window.  
High waves that can reflect the radar signal will  
produce the maximum amount of sea clutter.  
you want to adjust the radar gain yourself or  
have it adjusted automatically.  
You can change the sea clutter mode  
yourself or have it changed automatically to  
compensate for the sea conditions.  
To change the radar gain mode:  
MENU  
To change the sea clutter mode:  
1
From the radar window, press  
then  
MENU  
select Adjust Radar.  
1
From the radar window, press  
select Adjust Radar.  
then  
2
Select Gain Mode. There are three  
choices:  
2
Select Sea ClutterMode. There are  
four choices:  
Manual. Adjust the radar gain yourself  
to suit your local conditions and  
preferences.  
Manual. Adjust the sea clutter setting  
yourself.  
Auto. The radar gain is adjusted  
automatically.  
Harbour. The sea clutter setting is  
adjusted automatically to suit a harbour  
environment.  
Range rider. Select this to adjust the  
radar gain yourself for a particular radar  
range, then have those settings stored  
and automatically re-used whenever you  
operate at that range again.  
Offshore. The sea clutter setting is  
adjusted automatically to suit an offshore  
environment.  
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Range Rider. Adjust the sea clutter  
setting yourself for a particular radar  
range, then have those settings stored  
and automatically re-used whenever you  
operate at that range again.  
The random signals are returned from rain, hail,  
sleet, or snow and can result in a confusing  
display.  
If the rain clutter is set too low, there will be  
excessive rain clutter displayed whenever it’s  
raining. If the rain clutter is set too high, very  
large targets such as the coastline will appear to  
be hollow.  
18-6-4 Changing the sea clutter level  
If the sea clutter level is set too low, a lot of sea  
clutter will be displayed. If the sea clutter level is  
set too high, small targets may not be shown in  
the radar window.  
To change the rain clutter setting:  
MENU  
1
From the radar window, press  
then  
select Adjust Radar.  
If the sea clutter mode is set to Harbour or  
Offshore, and you adjust the sea clutter level  
manually, the sea clutter mode changes to  
Manual.  
2
Select Rain clutterthen use and  
to decrease or increase the setting.  
18-6-6 Changing the threshold level  
If you are in Range Rider mode when you adjust  
the sea clutter level, the sea clutter mode does  
not change to manual but the setting is stored  
and used automatically whenever you use the  
same range again.  
Use this to define the threshold level of the  
weakest echo that you want to show on the  
radar screen. The threshold level is shown as a  
percentage.  
100% is the maximum threshold level, meaning  
that only the strongest echoes are shown. 0% is  
the minimum threshold level, meaning that all  
echoes are shown.  
To change the sea clutter level:  
MENU  
1
From the radar window, press  
then  
select Adjust Radar.  
2
Select Sea Clutter Level then  
use and to decrease or increase the  
setting.  
To change the threshold level:  
MENU  
1
From the radar window, press  
then  
select Presentation.  
18-6-5 Changing the rain clutter  
2
Select Thresholdthen use and to  
Rain clutter consists of random dots that can  
merge into badly-defined echoes on your radar  
screen.  
decrease or increase the setting.  
18-7 Changing the echo expansion setting  
If you have several small targets in view and  
want to make them easier to see, use the echo  
expansion option. Note that the resolution  
decreases as the target size increases, so use  
this option only when target detection and  
visibility is more important that the quality of  
the display.  
To change the echo expansion setting:  
MENU  
1
From the radar window, press  
then  
select Presentation.  
2
Select Echo Expansion. There are  
three choices:  
Off. No echo expansion.  
1. Targets expanded x 2.  
2. Targets expanded x 3.  
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18-8 Turning the target trails on or off  
If you turn the target trails on, each target  
leaves a 30 second trail on the radar screen. You  
cannot change the length of the target trail.  
To change the target trails setting:  
MENU  
1
From the radar window, press  
then  
select Presentation.  
If you turn the target trails off, the targets do  
not leave trails.  
2
Set the Target trailsoption to  
(target trails are on) or (target trails are  
off).  
Note that if the radar motion mode is set to  
true, stationary targets won’t leave a trail.  
If the radar motion mode is relative, any target  
that is moving relative to your boat will leave a  
trail.  
18-9 Using the VRM/EBL  
Use one, or both of the VRM/EBL (Variable  
Range Markers/Electronic Bearing Lines) to  
quickly find the precise range and bearing of a  
target.  
18-9-1 Finding range and bearing with a fixed  
VRM/EBL  
From the radar window, press  
MENU  
1
2
3
4
then  
select VRM/EBL.  
A VRM can be fixed or floating. Use the VRM to  
find the range (distance) to the target.  
Select VRM/EBLthen 1 (VRM/EBL 1) or 2  
(VRM/EBL 2).  
A fixed VRM is shown as a thin, dashed, circle  
centred around your boat. Use this to find  
the distance of a target from your boat.  
Set Enable to to show the VRM and EBL on  
the radar window (or to hide them).  
Select EBL reference if you want to change  
the EBL bearing reference. There are two  
choices:  
You can move the centre of the VRM away  
from your boat; for example, to measure the  
distance between two islands. This is called  
a floating VRM.  
°R shows the EBL bearing relative to your  
boat’s head.  
The EBL is shown as a thin, dashed line  
extending from the centre of the VRM to the  
edge of the radar window. Use the EBL to find  
the bearing of the target.  
°M/°T shows the EBL bearing relative to  
magnetic North or true North.  
5
Select Adjustto change the positions of  
the VRM and the EBL so that you can align  
them with the target. Use:  
MENU  
1
From the radar window, press  
select VRM/EBL.  
then  
and to decrease and increase the  
radius of the VRM until it touches the  
target to measure the range.  
and to move the EBL until it touches  
the target to measure the bearing.  
6
7
The range and bearing of the target is  
shown at the bottom of the screen.  
If you want to hide (or change the  
settings for) the range rings, North line,  
MENU  
and/or heading line, press  
then select  
Radar.  
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8
To clear the VRM/EBL display, press ESC and  
repeat steps 1 and 2. Then set Enable to  
If you want to find the range and bearing of  
5
Select Set centreto move the VRM  
and EBL centre away from your boat. Use the  
arrow keys to move the centre so that it is  
aligned over the first location.  
ENTER  
.
another target, repeat the sequence using the  
other VRM/EBL. This is shown in a different  
pattern.  
6
7
Press  
to save the new centre position,  
MENU  
then press  
and reselect the VRM/EBL.  
Select Adjust to change the positions of the  
VRM and the EBL so that you can align them  
with the second location. Use:  
18-9-2 Finding range and bearing with a  
floating VRM/EBL  
If you move the centre of a VRM away from  
your boat it is called a floating VRM. Use this  
to measure the range and bearing between  
two locations on the radar window, such as a  
headland and a buoy.  
and to decrease and increase the  
radius of the VRM until it touches the  
second location to measure the range.  
and to move the EBL until it touches  
the second location to measure the  
bearing.  
1
2
3
4
From the radar window, press MENU then  
select VRM/EBL.  
8
9
The range and bearing of the target is  
shown at the bottom of the screen.  
Select VRM/EBL then 1 (VRM/EBL 1) or 2  
(VRM/EBL 1).  
If you want to hide (or change the settings  
for) the range rings, North line, and/or  
heading line, press MENU then select Radar.  
Set Enable to to show the VRM and EBL on  
the radar window (or to hide them).  
Select EBL reference if you want to change  
the EBL bearing reference. There are two  
choices:  
10 To clear the VRM/EBL display, press ESC and  
repeat steps 1 and 2. Then set Enable to  
.
If you want to find the range and bearing  
between two other locations, repeat the  
sequence using the other VRM/EBL. This is  
shown in a different pattern.  
°R shows the EBL bearing relative to your  
boat’s head.  
°M/°T shows the EBL bearing relative to  
magnetic North or true North.  
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18-10 Changing the PPI position  
You can move the PPI (Plan Position Indicator)  
centre to a different location if you are in  
Relative motion mode. (If you are in True  
motion mode, the radar automatically positions  
the PPI centre.)  
Look Ahead. The PPI centre is positioned  
so that the radar window is offset from  
the centre to give you the maximum  
view ahead.  
Set. Offset the PPI centre in the radar  
window. (This works only when you are  
using relative motion (RM) mode). Use  
To change the PPI position:  
1
From the radar window, press MENU then  
select Position.  
the arrow keys to move the PPI centre  
ENTER  
to the new position then press  
to  
2
There are three choices:  
confirm. The new position must allow  
most of the radar sweep to appear on the  
radar window; if it doesn’t, the PPI centre  
will be moved as close as possible to the  
desired position.  
Centre. The PPI centre is in the centre  
of the radar window so that all other  
objects move relative to your boat.  
18-11 Using the radar guard zones  
Use either or both of the two radar guard zones  
and alarms to notify you when a target enters  
or exits a specified area around your boat.  
18-11-2 Displaying the area covered by a radar  
guard zone  
1
From the radar window, press MENU then  
You can customize the size and shape of the  
radar guard zones and set up alarms.  
select Guard Zone.  
2
3
Select Zone then radar guard zone 1 or radar  
guard zone 2.  
Set Enable to (show the radar guard zone)  
or (hide the radar guard zone).  
18-11-3 Change the setting for a radar guard  
zone alarm  
When a radar guard zone is on, the guard zone  
alarm is set automatically but you can change  
the setting to suit your preferences.  
1. From the radar window, press MENU then  
select Guard zone.  
1
2
3
From the radar window, press MENU then  
select Guard Zone.  
18-11-1 Turning a radar guard zone on or off  
Two radar guard zones are available. You can  
turn either or both on or off.  
Select Zone then radar guard zone 1 or radar  
guard zone 2.  
Select Alarm when. There are three choices:  
To turn a radar guard zone on or off:  
Enter sounds the alarm only when a  
target enters the radar guard zone.  
1
From the radar window, press MENU then  
select Guard zone.  
Exit sounds the alarm only when a target  
leaves the radar guard zone.  
2
Select Zone. There are two choices:  
1 selects radar guard zone 1.  
2 selects radar guard zone 2.  
Both sounds the alarm when a target  
enters or leaves the radar guard zone.  
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18-11-4 Adjusting the boundaries of a radar  
guard zone  
To adjust the boundaries and change the area  
18-11-5 Adjusting the sensitivity of the alarm  
You can set the sensitivity of the alarm for the  
radar guard zones, to define the size of the  
target that will trigger the alarm. The size of  
target is shown as a percentage.  
that is covered by a radar guard zone:  
1
2
3
From the radar window, press MENU then  
select Guard Zone.  
100% is maximum sensitivity, meaning that very  
small targets will trigger the guard zone alarm.  
0% is minimum sensitivity, meaning that only  
very large targets will trigger the alarm.  
Select Zone then 1 (radar guard zone 1) or 2  
(radar guard zone 2).  
Select Adjust to display the current  
boundaries of that radar guard zone. The  
following information is also shown in the  
top left corner:  
The same sensitivity setting is applied to both  
of the radar guard zones if both are turned on.  
To set the alarm:  
1
2
3
From the radar window, press MENU then  
select Guard Zone.  
Guard Zone The number shows the radar  
guard zone that is selected.  
Select Zone then select 1 (radar guard zone  
1) or 2 (radar guard zone 2).  
Sector or Circular The shape of the radar  
guard zone.  
Select Alarm sensitivity then use and to  
decrease or increase the setting.  
INR The distance between the inner  
boundary and your boat.  
OUR The distance between the outer  
boundary and your boat.  
WDT The angular width of the radar  
guard zone (in degrees).  
BRG The bearing of a line drawn from  
your boat through the centre of the radar  
guard zone (in degrees).  
4
5
Use and to select the parameter to  
change.  
Then use and to change the parameter.  
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19 Setting up the M121/M84  
The M121/M84 has a number of advanced  
features which are set up through the setup  
menu. We recommend that you become  
familiar with the operation of the unit using the  
default settings before making any changes in  
these menus.  
Note:  
1
2
3
The Setup menu options are explained in  
the following sections.  
Section 2-1 describes how to set or change  
data in the setup menus.  
The setup data available will depend on the  
optional sensors and instruments installed.  
SETUP  
To go to a setup option menu, press  
MENU  
(M121 only) or press  
twice, to display the  
setup menu, then select an option.  
System Setup (see section 19-1)  
Chart Setup (see section 19-2)  
Chart General Setup (see section 19-2)  
Chart Water Setup (see section 19-2)  
Chart Land Setup (see section 19-2)  
Chart Other Setup (see section 19-2)  
Sonar Setup (see section 19-3)  
Radar Setup (see section 19-4)  
GPS Setup (see section 19-5)  
Fuel Setup (see section 19-6)  
Track Setup (see section 19-7)  
AIS Setup (see section 19-8)  
Logs Setup (see section 19-9 )  
See the SmartCraft Gateway Instalation  
and Operation Manual  
Alarms Setup (see section 19-10)  
Units Setup (see section 19-11)  
Comms Setup (see section 19-12)  
Calibrate Setup (see section 19-13)  
Time Setup (see section 19-14)  
Favorites Setup (see section 19-15)  
Simulate Setup (see section 19-16)  
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19-1 Setup > System  
MENU  
Press  
twice, then select System:  
Factory reset  
This option returns all of the Instrument settings  
(except the language, waypoints and routes) to  
the default factory settings shown on the setup  
menus.  
About  
The about window shows:  
The software version and date.  
The world chart version.  
Any card fitted.  
The number of waypoints, routes and tracks  
you have stored.  
Connector wiring information.  
Language  
Select the language for the windows. The  
options are: English, Italian, French, German,  
Spanish, Dutch, Swedish, Portuguese, Finnish  
and Greek.  
Tip: In case you can’t read the current  
language, the language setting is found at the  
top of the system menu.  
Backlight  
Select the backlight level for the keys and  
display (see also section 2-3)  
In the unlikely event of having to contact a  
Northstar dealer for service, quote the software  
version number and date.  
Night mode  
Night mode sets the palette for all windows  
Sonar  
Normal palette, for daytime  
Disable any sonar transducer and disable  
sonar functions.  
All windows have a palette optimized for  
night time.  
A sonar transducer is fitted. Enable sonar  
operation.  
See also section 2-3. To change only the chart  
palette, see section 19-2.  
See section 19-3.  
Beep volume  
Select the beep volume for key presses.  
Radar  
No appropriate Radar system is fitted.  
Disable RADAR.  
Auto power off  
See section 2-2.  
An appropriate Radar receiver is fitted.  
Enable AIS.  
See section 19-4.  
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SmartCraft  
Buddy track  
No SmartCraft gateway is fitted. Disable  
No appropriate Northstar DSC VHF radio is  
SmartCraft functions.  
fitted. Disable Buddy track.  
SmartCraft gateway is fitted. Enable  
SmartCraft operation.  
An appropriate Northstar DSC VHF radio is  
fitted. Enable Buddy track.  
See section 20-8.  
See section 20-10  
AIS  
No appropriate AIS receiver is fitted.  
Disable AIS.  
An appropriate AIS receiver is fitted.  
Enable AIS.  
See section 19-8.  
19-2 Setup > Chart  
MENU  
Press  
twice, then select Chart:  
Course up:This option is only available  
if the boat is navigating to a destination. The  
chart is rotated so that the plotted course to  
the destination is vertical.  
Rotation  
The options for chart rotation are:  
North up: North is always at the top of  
the chart window.  
Palette  
Track up: The chart is rotated so that the  
boat direction is to the top of the window.  
This option is useful for navigating narrow  
harbours or rivers. The Instrument asks for  
a course deviation resolution; this is how  
much the boat direction needs to change to  
make the chart redraw.  
Select the color scheme for the LCD window.  
The options are:  
Normal  
Sunlight: Brighter colors, more visible in  
sunlight.  
Night: Reversed colors for night, to  
Tip: If the chart redraws too frequently,  
increase the course deviation setting.  
preserve night vision.  
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Latitude and longitude coordinates  
displayed on any NMEA repeaters match the  
coordinates on the Instrument. However,  
latitude and longitude coordinates  
broadcast on any NMEA VHF transmitter will  
be slightly offset from coordinates on a WGS  
84 chart.  
Map datum  
Instrument GPS positions are based on a  
worldwide reference (datum) known as WGS  
84. Most paper charts are based on WGS  
84. However, some paper charts are based  
on other datums In these cases, the latitude  
and longitude coordinates of objects on the  
Instrument chart window are different to the  
latitude and longitude coordinates of these  
objects on the paper chart. This applies to all  
objects, such as the boat, waypoints, tracks,  
lines of latitude and longitude and cartographic  
features such as land, rocks, buoys and depth  
contours.  
Map shift  
!
WARNING  
Map shift is for eliminating minor offsets.  
It should not be used if the correct datum  
is available. Use map shift with caution:  
incorrect application will cause incorrect  
boat positions.  
Use Map datumto select the Instrument map  
datum to match the datum of the paper chart.  
Then, the latitude and longitude coordinates  
of objects displayed on the Instrument  
will change to match the corresponding  
coordinates on the paper chart.  
Some charts have consistent position errors. To  
correct this, apply a map shift. After a map shift:  
The positions of cartographic features (such  
as land, rocks, buoys and depth contours)  
move on the Instrument chart window to  
where they should be.  
Setting map datum  
1
2
In the Chart setup menu, select Map datum.  
Select the map datum for the paper chart  
you are using.  
The positions of the boat, waypoints,  
tracks, and lines of latitude and longitude  
on the Instrument chart window remain  
unchanged.  
3
If you select a datum other than WGS 84  
the Instrument asks if you want to apply the  
NMEA datum offset (see below).  
Applying a map shift  
1
2
3
Move the boat to a known point on the  
chart, for example a marina berth.  
!
WARNING  
In the Chart setup menu, select  
Map shift.  
Move the cursor to the position on the chart  
When you change to a chart with a different  
datum, change the Instrument map datum  
again.  
where the boat actually is.  
MENU  
4
5
Press  
Press  
and select Set.  
NMEA datum offset  
ESC  
to set the new map shift.  
If you select a map datum other than WGS  
84, the map datum offset can be applied to  
latitude and longitude coordinates sent on the  
Instrument NMEA output:  
The boat will now be displayed at its  
actual location.  
Clearing the map shift  
Clearing the map shift removes any map  
shift from the cartographic features on the  
Instrument chart window.  
Latitude and longitude coordinates  
displayed on any NMEA repeater do not  
match the coordinates on the Instrument.  
Latitude and longitude coordinates  
broadcast on any NMEA VHF transmitter will  
be the same as the coordinates on a WGS 84  
chart.  
1
In the Chart setup menu, select  
Map shift.  
MENU  
2
3
Press  
Press  
and select Clear.  
ESC  
.
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General submenu  
Plotter mode  
Only scales available on the chart card can be displayed.  
If you press or to select a chart scale which is not available, on the chart card, the chart win-  
dow will change to this scale but will only display the boat position and track (if enabled). The rest of  
the window is white with black crosshatch lines and no chart information is displayed. This is useful  
to zoom to a small scale to track small boat movements or if there is no detailed chart for an area.  
Mixing levels  
Anticlutter  
Mixes lower detail charts with higher detail charts on chart boundaries.  
:Lower detail chart is not shown.  
:Lower detail chart shown; this is slower to redraw.  
Names and icons shown. Note: this is independent of the change in detail shown at different  
zoom levels.  
Hides some less important names and icons when they overlap to make the chart clearer.  
Non marine chart data shown  
Value added data  
Projected course  
The Instrument can estimate the course after a given time, based on the current speed and heading  
(see section 3-4). The options are 2 minutes, 10 minutes, 30 minutes, 1 hour, 2 hours or Off.  
CDI scale  
See Appendix C. The options are 0.05, 0.1, 0.2, 0.5, 1.0, 2.0, 4.0 and 10.0 distance units.  
displays a latitude and longitude grid.  
Lat/lon grid  
Boundaries  
Displays boundaries around areas where more detailed chart coverage is available: Auto shows the  
next four detail levels; On shows all.  
Text/icon size  
Select the size of chart text and icons.  
Water submenu  
Water features  
displays nature of sea bed (for example, M shows areas of mud)  
and tide station icons.  
Bathymetric[s] lines  
Spot soundings  
Displays underwater depth contours between Bath & dndgs min  
and max.  
Displays underwater depth contours between Bath & dndgs min  
and max.  
Bath & sndgs min  
Bath & sndgs max  
Tidal stream  
The minimum depth for Bathymetricsand Spot soundings.  
The maximum depth for Bathymetricsand Spot soundings.  
displays dynamic tide flows: arrows on a chart showing the present tide stream and orientation  
(requires a GPS fix and an NT-MAX card)  
Land submenu  
Land features  
displays land features, for example regions, rivers, roads, railways, airports.  
displays land contours, shaded like depths (requires an NT Max card)  
Land elevation  
Other submenu  
Waypoints  
Displays waypoints: Hide allonly displays waypoints on any selected route; Selecteddisplays  
waypoints with their display option set to Icon or I+N (Icon and Name); Show alldisplays all  
waypoints (see section 5).  
Names  
Lights  
displays place names.  
Light House window options: Off hides all light indicators (the icon still shows); No sectors  
hides sectors; Onshows sectors; Animated activates light animation.  
Note: with light animation enabled, animation only operates chart.  
Nav-aids  
Displays signals (fog, radar, radio stations) and buoys. Intand USselect the icon format; Simpl  
draws simpler icons.  
Attention areas  
displays attention area boundaries and information icons ; attention areas are important areas,  
such as restricted anchorages or shallow areas.  
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19-3 Setup > Sonar  
MENU  
Press  
twice, then select Sonar:  
Fish depth labels  
When this is turned on, the depth of a fish is  
printed next to the fish arch.  
Fish filter  
Use this to select the minimum fish size that will  
be displayed as a fish symbol and to trigger the  
Fish alarm. The options are: Small, Medium  
and Large.  
Fish sensitivity  
Selects the minimum strength fish echo that  
will be displayed as a fish symbol. Higher values  
will display more fish symbols.  
Frequency  
There is a choice of: 200 kHz, 50 kHzand  
Mixed. For information about selecting a  
suitable frequency for the water conditions, see  
section 9-3.  
Digit size  
Use this to remove or change the size of the  
depth window on the sonar windows. There is a  
choice of: Small, Mediumand Large.  
Scroll speed  
Palette  
Use this to set the scroll speed on the display.  
There is a choice of: Very Fast, Fast,  
Medium, Slowand Pause.The depth of  
the water also affects the speed of the display.  
Use this to select a color palette. Each color  
within the palette represents a different echo  
strength, as shown on the sonar windows.  
There is a choice of five color palettes: Black,  
Blue, White, Vividand 8 color. The first  
four palettes display more detail, and each color  
covers a 1.5 dB signal range. The 8 color  
palette displays less detail, and each color  
covers a 3 dB signal range.  
Faster scroll speeds combined with a slow  
boat speed (typically between 2 and 6 knots)  
shows the most fish detail. Mediumor Slow  
scroll speeds result in sonar information being  
displayed over a longer period, but with less  
detail (see Section 9-2).  
Interference filter  
Fish symbols  
No filter, normal setting.  
The Instrument always displays echoes from  
fish (fish arches, see section 9-4). If fish symbols  
are on, a symbol is displayed over the arch (see  
section 9-4). The options are:  
Filters the echo signal to remove spiky  
interference such as engine noise or depth  
sounders on nearby boats.  
Off: No fish symbol is displayed.  
Funor Normal: A fish symbol is displayed.  
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Noise filter  
Pulse length  
Averages the echo signal to remove rapid  
changes. Select Medium or High to give a  
smoother bottom trace–this may help to detect  
a deeper bottom; however these settings may  
also remove fish echoes. Select Off for best  
fishfinding.  
This can be used to specify the length of  
the transmitted ultrasonic pulse. A short  
pulse length improves the window detail but  
contains less energy, therefore it does not  
penetrate as deeply into the water as a longer  
pulse.  
There is a choice of Auto, Short, Medium  
Surface clutter filter  
or Long. The Auto setting is recommended.  
Use this filter to hide the surface noise. Any  
significant echoes (such as fish) will still be  
displayed.  
Pulse power  
This can be used to specify the power output  
of the transmitted ultrasonic pulse. Low power  
output conserves the battery and produces a  
clear display in shallow water.  
There is a choice of Auto, Low, Medium or  
High. The Autosetting is recommended.  
19-4 Setup > Radar  
Note: This option is shown only when the radar  
is enabled (see Section 18-3)  
Rotation  
The current radar rotation is shown in the top  
left corner of the radar screen. If COG data or  
heading data is not available from a compass,  
the radar rotation is automatically set to Head  
up.  
1
Press MENU twice to display the Setup  
menu, then select Radar:  
However, you are strongly recommended to  
use a good quality product (such as a Northstar  
HS02, HS03 or Autopilot) to provide heading  
data.  
If heading data is available from a compass, the  
options are:  
North up works only when COG data or  
heading data from a heading sensor is  
available. North is always at the top of the  
radar screen.  
You can easily compare the radar screen to a  
chart in North up.  
Head up means that the radar image rotates  
underneath your boat, so the direction in  
which you are heading is pointing to the top  
of the radar screen. You can easily compare  
the visual view in front of your boat with the  
radar screen.  
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Course up works only when COG data or  
heading data from a heading sensor is  
available and there is an active route. It  
means that your desired heading is always  
pointing to the top of the radar screen so  
that you can compare the leg bearing of the  
active route with the radar screen. (If you’re  
in Course up rotation but don’t have an  
active route, the radar uses Head up rotation  
until a route is made active.)  
There are four choices:  
Off. Interference rejection is off.  
Low operates the interference rejection at  
minimum strength.  
Medium operates the interference rejection  
at medium strength.  
High operates the interference rejection at  
maximum strength. This setting can make  
it more difficult to detect some targets and  
radar beacons. Use this setting only when  
Motion mode  
necessary.  
True motion mode is not available if there is  
no position data, and no heading or COG data.  
However, you are strongly recommended to  
use a good quality product (such as a Northstar  
HS02, HS03 or Autopilot) to provide heading  
data.  
Palette  
Select the color scheme for the radar window.  
Digit size  
The range of the radar is shown on the radar  
window; for example 1/16. You can show this  
information in small, medium or large digits.  
There are two choices:  
Relative (RM). Your boat remains in a fixed  
location on the radar screen and all other  
objects move relative to your position.  
(You can choose the position of the fixed  
location, see Section 18-10). RM is the  
default.  
Range ring  
The range rings and compass ring help you to  
quickly estimate the range and bearing of a  
target from your boat.  
The range ring and compass ring are shown.  
The number of range rings and the spacing  
interval between them is set automatically  
according to the range setting. The current  
spacing interval is shown in the top left corner  
of the radar window.  
True (TM). Your boat, and moving targets,  
move across the radar screen as you travel.  
All stationary objects remain in a fixed  
position. You must have position data, and  
heading or COG data for this option to be  
Range ring and compass ring are hidden.  
available.  
North line  
Interference filter  
Whatever the radar windorotation, you can  
always show the blue North line.  
If the radar on another boat is operating at  
the same frequency as your radar, it can cause  
interference patterns on the radar window.  
If the bearing mode is set to:  
magnetic, the North line always points to  
magnetic North.  
Interference patterns always appear in a  
different place with each sweep. They can be  
randomly scattered bright dots or dotted lines  
that extend from the centre to the edge of the  
radar window, often producing a spiral pattern.  
Generally, the stronger the interference, the  
wider the interference lines.  
true, the North line always points to true  
North.  
Show the North line.  
Hide the North line.  
Use the interference rejection option to reduce  
both the interference patterns and the width of  
the interference lines.  
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Adjust this on a chart window with the radar  
overlay on.  
Heading line  
The heading line is a white line that extends  
from your boat to the edge of the radar  
window.  
1
Select Zero bearing then use the arrow keys  
to enter the new bearing angle.  
Show the heading line.  
Hide the heading line.  
Zero range  
The zero range is also known as the radar range  
offset and as the trigger delay.  
19-4-1 Setup > Radar > Installation  
If your radar window shows a blank, black circle  
around the centre or a solid circle of color at  
the centre, you need to adjust the zero range  
setting until this circle disappears or almost  
disappears. Ideally, the radar sweep should start  
at your boat (a radar range of zero).  
Note: This option is shown only when the radar  
is enabled (see Section 18-3)  
1
2
Press MENU twice to display the Setup  
menu, then select Radar.  
Select Installation:  
To adjust the zero range setting:  
1
Position your boat about 45 to 90 m (50  
to 100 yards) away from and parallel to a  
straight-walled jetty or similar feature.  
2
Adjust the gain setting if necessary, so that a  
reasonably good image of the jetty echo is  
displayed on the radar window. At this stage,  
the jetty echo may appear to be bent.  
Park position  
3
Select Zero range then use the arrow keys to  
adjust the zero range setting until the jetty  
echo appears as a straight line on the radar  
window.  
If your radar has an open array and you  
take it out of enabled mode, the open array  
continues to rotate for a short distance before  
it finally stops. The stop position is known as  
the park position. You can adjust the angle of  
the parking position so that the open array  
will always stop at your preferred position; for  
example, facing the bow.  
Antenna height  
The Installation Manual for your Northstar radar  
explains how to find the optimum height for  
your radar scanner (antenna).  
Select Antenna height then enter the height of  
the antenna above sea level.  
1
Select Park position then enter the angle of  
the new park position.  
Note: You may need to try a few different park  
positions to find the correct one. The strength  
of the wind will also affect the park position.  
Zero bearing  
Use the zero bearing alignment to rotate the  
radar image, one degree at a time, so that a  
known object dead ahead is directly under the  
boat’s heading marker.  
This means that the radar image is aligned  
with the displayed chart and the compass.  
An accurate bearing alignment is particularly  
important when the radar image is overlaid  
onto the chart.  
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19-5 Setup > GPS  
MENU  
Press  
twice, then select GPS:  
Static Navigation  
When the boat stops or moves very slowly,  
the calculated GPS speed and course become  
erratic. Static navigation allows the erratic  
values to be filtered:  
0.01 to 99.9: If the boat speed is slower than  
this, the speed is displayed as zero and the  
course stays unchanged.  
0 (Off): The calculated speed and course are  
always used.  
GPS Source  
Speed and Course Filter  
NMEA: Use the external GPS antenna  
supplied or an external GPS or DGPS source  
connected via NMEA (see section 20-11).  
Waves and wind cause the boat speed and  
course to fluctuate slightly. To give stable  
readings, the Instrument calculates these values  
by taking several measurements and averaging  
them.  
NavBus: Use an external GPS or DGPS  
source connected via NavBus (see section  
20-10).  
A lower value averages measurements over  
a shorter period of time. This gives the most  
accurate value but has the most fluctuations.  
DGPS Source  
Refer to section 20-5  
Restart GPS  
A higher  
Refer to section 20-5  
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19-6 Setup > Fuel  
Fuel functions require optional fuel flow sensors  
MENU  
to be installed. Press  
Fuel:  
twice, then select  
From tank: The fuel tank the engine is  
connected to.  
Flow filter: Most engines do not draw fuel  
from the tank at a steady rate. To give a stable  
fuel flow reading, the M121/M84 calculates  
the flow by taking several measurements and  
averaging them. Use the Flow filter to set the  
period over which the fuel flow is averaged.  
!
WARNING  
The Flow filter can be set from 0 to 30 seconds.  
Use the lowest value which gives a stable flow.  
Usually a value of 5 to 10 seconds will give a  
satisfactory result for two-stroke carburetor  
engines. Fuel injected or four-stroke engines  
may require a larger value.  
Fuel consumption can change drastically  
depending upon the boat loading and the  
sea conditions. Always carry adequate fuel  
for the journey, plus a reserve.  
This setting affects the Fuel flow and Fuel  
economy reading on the Fuel display but it  
does not affect the Fuel used reading.  
Source  
Select the fuel flow sensors to use if the boat  
has more than one set of fuel sensors. Normally  
select Auto.  
Setup tanks  
If the boat has more than one tank, select Tank  
and select each tank in turn.  
Num engines  
Set the number of engines, or select 0to  
disable the fuel functions. If there are two  
engines they are called port and starboard.  
For the selected tank, you can enter:  
Num tanks  
Set the number of fuel tanks. If there are two  
tanks they are called port and starboard.  
Setup engines  
If the boat has more than one engine, select  
Engine and select each engine in turn.  
For the selected engine, you can enter:  
Tank size: The tank capacity. Northstar  
recommends measuring tank size by draining  
the fuel tank, filling it to capacity and using the  
fuel dispenser’s reading. Beware of air pockets,  
especially in underfloor tanks.  
Fuel alarm: See section 13-4.  
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Fuel consumption curve  
See section 13-6.  
Speed source  
If both water speed and ground speed  
are available, select which to use for fuel  
calculations (see section 10-5-1).  
Max fuel flow  
The maximum fuel flow from a fuel tank to be  
displayed on an analog fuel flow gauge (see  
section 8)  
Max RPM  
The maximum engine RPM to be displayed  
on an analog RPM gauge. Required only if  
Northstar diesel flow sensors are installed. Enter  
the maximum RPM you know you can achieve  
for the engine rather than the maker’s value.  
19-7 Setup > Track  
MENU  
Tracking records and displays the boat’s course  
on the chart (see section 3-5). Five different  
tracks can be recorded: track 1 has up to 2000  
points and tracks 2, 3, 4 and 5 have up to 500  
points each.  
Press  
twice, then select Track:  
Record  
Off: The Instrument stops recording a track.  
1 to 5(select a track number): The  
Instrument starts recording the boat’s  
course into the selected track.  
Display  
Off: No track is shown on the chart.  
1 to 5(select a track number): The  
selected track is shown on the chart.  
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Plotting Interval  
Select the plotting and recording interval. The  
options are Distanceor Time.  
Distance  
Tip: Use the user card window to check the  
number of points recorded in each track  
(see section 15).  
Send track  
This option is included for compatibility with  
older units. For information, see your Northstar  
dealer.  
Select the distance plotting interval: 0.01, 0.05,  
0.1, 0.5, 1.0, 2.0, 5.0 or 10.0 distance units.  
Time  
Delete track  
The data in the track selected for Record (see  
above) is deleted.  
Select the time plotting interval: 1, 5, 10 or 30  
seconds or 1 minute.  
Memory used  
The percentage of memory used in the track  
being recorded.  
19-8 Setup > AIS  
Note: This feature requires an AIS receiver.  
Filter by speed  
There are multiple methods to filter AIS vessels  
that are displayed onto the charts.  
Vessels with speed below the value selected  
are filtered off the charts. Default is set to 0 nm  
allowing all vessels to be displayed onto the  
chart.  
Show Dangerous Only  
Show only vessels that have a TCPA/CPA below  
the trigger values. This filter will override any  
other filter option.  
Dangerous Vessel Alarm  
When enabled an alarm will activate when  
both the TCPA and CPA are less than the trigger  
values.  
Note: Even when this setting is disabled the  
dangerous vessels will still be indicated on the  
chart.  
Filter by Type  
Vessel types that are not selected will be filtered  
off the chart. Default is set to all types enabled  
allowing all vessels to be displayed on the chart.  
TCPA Limit  
Set the Time of Closet Point of Approach limit.  
Filter by distance  
CPA Limit  
Set the Closet Point of Approach limit.  
Vessels outside the radius selected from our  
current position are filtered off the chart. Default  
value is set to 300 nm allowing all vessels to be  
displayed on the chart within that distance.  
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Projected Course  
Proximity Alarm  
Show the estimated course of all vessels based  
When enabled an alarm will activate when any  
on their current SOG and COG.  
AIS vessel is within the proximity alarm radius.  
Range Rings  
Show a selectable number of range rings  
around the boat. The rings are drawn in  
multiples of the current chart scale.  
19-9 Setup > Logs  
MENU  
The values can be reset independently of each  
other. These log values are saved when the unit  
is turned off.  
Press  
twice, then select Logs:  
Reset trip dist  
This resets the trip distance to zero.  
Reset total dist  
This option resets the total distance to zero.  
Reset engine hours  
Use this option to reset the engine hours to  
zero. This can be useful after an engine service  
or to count the engine hours between service  
intervals.  
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19-10 Setup > Alarms  
MENU  
For all alarms select to turn the alarm on or  
select to turn the alarm off. For most alarms  
there is a trigger value. The alarm will sound  
each time the alarm value equals the trigger  
value.  
Press  
twice, then select Alarms:  
For example, the Dangeralarm will sound if  
the boat comes closer to a danger waypoint  
than the trigger value and the Anchor alarm  
will sound if the boat moves by more than the  
trigger value.  
You can display the alarm status in the data  
header (see section 2-7-3). The alarm status  
shows the symbol for each alarm that is on. The  
symbol is normally black and turns red if the  
alarm triggers.  
Symbol Alarm  
Beeper  
Alarm sounds when it is on and the:  
Arrival radius  
Boat is closer to the destination or to a waypoint than the alarm trigger  
value  
Anchor alarm  
XTE  
Boat moves by more than the alarm trigger value  
Boat moves off course by more than the CDI scale (see section 5)  
Boat comes closer to a danger waypoint than the alarm trigger value  
Danger  
Too shallow  
Too deep  
Fish  
1/5 sec  
Depth is less than the alarm trigger value  
Depth is greater than the alarm trigger value  
Echo matches the profile of a fish  
1/2 sec  
1 short beep  
1/2 sec  
Temperature  
Temperature equals the alarm trigger value  
Rate of change of temperature equals the alarm trigger value  
Temperature  
rate  
1/2 sec  
Low battery  
Low fuel  
1/2 sec  
1/2 sec  
Battery voltage is less than the alarm trigger value  
Low fuel remaining equals the alarm trigger value; on a multitank boat  
you can set separate alarms for each tank (see section 13-4)  
Loss of DGPS fix  
Loss of GPS fix  
Instrument can not receive the DGPS signal (beacon, WAAS or EGNOS)  
Instrument can not receive the GPS signal (this alarm is always on)  
Loss of AIS  
receiver  
M121/M84 is no longer receiving communication from the AIS receiver  
(Alarm is on when AIS is enabled)  
communication  
Dangerous  
vessel  
The TCPA/CPA of another vessel is less than the trigger values  
(see section 13)  
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19-11 Setup > Units  
MENU  
Press  
twice, then select Units:  
Depth  
ft (feet), m (metres) or fa (fathoms)  
Height  
ft (feet) or m (metres)  
Fuel  
Litres, USGal (US gallons) or ImpGal (Imperial  
Gallons)  
Compass  
°T (True north) or °M (Magnetic north)  
Temperature  
°F (Fahrenheit) or °C (Celsius)  
The default units are shown above.  
Distance  
Wind (optional)  
nm (nautical miles), mi (miles) or km  
Requires a wind instrument: True or App  
(kilometers)  
(Apparent)  
Note: that the units for wind speed are the  
speed units.  
Distance small  
ft (feet) or m (metres)  
Pressure  
Requires SmartCraft: kPa or psi  
Speed  
kn (knots), mph (miles per hour) or kph  
Baro (Barometric pressure)  
(kilometers per hour)  
Requires a Northstar VHF receiver with  
barometer connected by NavBus: InHg or mB.  
19-12 Setup > Comms  
Use this feature when the Instrument is  
connected to other Northstar instruments  
through NavBus or any compatible NMEA  
instrument.  
NMEA out  
NMEA is generally used with third party  
instruments (see section 20-12). Select this to  
transmit NMEA sentences, for example to an  
autopilot.  
MENU  
Press  
twice, then select Comms:  
NMEA data  
Use this to specify which NMEA sentences will  
be transmitted (see section 20-12 and Appendix  
A).  
Lat/lon dps  
Select the number of decimal points used for  
latitude and longitude transmitted in NMEA  
sentences.  
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NavBus  
NavBus Group  
NavBus is the preferred method for connecting  
the Instrument to other Northstar instruments.  
Select this if the instruments are connected  
using NavBus.  
Use this when a group of Northstar instruments  
are connected together using NavBus, to  
specify a group of instruments for backlighting,  
if required. Then, if the backlight setting on one  
instrument in the group is adjusted, the other  
instruments change automatically. Otherwise,  
select 0. See section 20-10.  
19-13 Setup > Calibrate  
MENU  
Press  
twice, then select Calibrate:  
Calibrating speed:  
1
2
3
Travel at a constant, known speed.  
In the Calibrate menu, select Speed.  
Press or to change the displayed speed  
to the true value.  
ENTER  
4
Press  
.
Speed filter  
Waves and wind cause the boat speed from the  
paddlewheel transducer to fluctuate slightly. To  
give stable readings, the Instrument calculates  
these values by taking several measurements  
and averaging them. Set the Speed filter to the  
lowest value which gives stable readings. The  
range is 1 to 30 seconds or Off (0).  
Speed  
This calibrates the speed from a paddlewheel  
sensor connected to the Instrument. Calibration  
may be required because different hull shapes  
have different flow characteristics. Obtain an  
accurate measurement of the boat’s speed from  
a GPS receiver; or by following another boat  
travelling at a known speed; or by making a  
timed run over a known distance.  
Temperature  
The factory settings should be sufficiently  
accurate for normal usage. To calibrate the  
temperature readout, first measure the water  
temperature with a thermometer known to be  
accurate.  
Note: for accurate calibration:  
The speed from a GPS receiver should be  
greater than 5 knots.  
The speed from another paddlewheel  
transducer should be between 5 and 20  
knots.  
Use the cursor keys to display the temperature  
readout box, then increase or decrease the  
value to match the measured temperature. The  
temperature can be set from 32° to 99.9°F (0° to  
37.7°C) with a resolution of 0.1° unit.  
Best results are achieved in calm conditions  
where there is minimal current (best at high  
or low tide).  
To change the units between °F (Fahrenheit) or  
°C (Celsius), see section 19-11.  
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Temperature filter  
Water turbulence and currents cause the water  
temperature to fluctuate slightly. To give stable  
readings, the Instrument calculates these values  
by taking several measurements and averaging  
them. Set the Temperature filter to the lowest  
value which gives stable readings. The range is  
1 to 30 seconds or Off (0).  
Transducer; depths  
measured below  
here  
A
B
Keel Offset  
Depths  
measured  
below here  
A depth transducer measures depths below  
where the transducer is mounted on the boat,  
usually the bottom of the boat. The Instrument  
calculates the depths to display by adding the  
keel offset to all measured depths.  
A Have a zero keel offset to display depths  
below the transducer.  
Depths measured  
below here  
C
B Enter a positive keel offset to increase the  
displayed depth. For example to display the  
total depths below the surface, enter the  
depth of the transducer below the surface.  
Speed range  
C Enter a negative keel offset to decrease the  
displayed depth. For example, to display the  
depths of clear water below the boat, enter  
minus the depth of the deepest part of the  
boat below the transducer.  
The maximum reading to display on an analog  
boat speed gauge (see section 11). Choose a  
range suitable for your boat.  
Fuel  
See section 13-7, Calibrate.  
19-14 Setup > Time  
MENU  
1
2
Select Local offset.  
Press  
twice, then select Time:  
Press or to change the offset, then  
ENTER  
press  
.
Time format  
The options are 24 hour or 12 hour.  
Date format  
The options are dd/MMM/yy, MMM/dd/yy,  
dd/MM/yy or MM/dd/yy.  
Local offset  
The difference between local time and UTC  
(GMT). Change local offset when daylight  
saving time starts and ends. The range is 0 to  
13 hours, in 30 minute steps.  
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19-15 Setup > Favorites  
See section 2-7-2.  
19-16 Setup > Simulate  
Simulate mode is a way of becoming familiar  
with the Instrument (see section 2-6).  
MENU  
The options required for Normal are:  
Speed: The simulated boat speed to use.  
Course: The simulated course over ground.  
Press  
twice, then select Simulate:  
Note: To select the start point, go to the chart  
window before starting the simulation. Then:  
To start the simulation from the boat  
ESC  
position, press  
boat mode.  
to switch to centre on  
To start the simulation from a different point,  
move the cursor to that point on the chart.  
Tip: To calculate a course, use the cursor (see  
section 3-2-1).  
Simulate  
Turn simulate mode off  
Tip: As the boat moves, vary Course to  
Turn simulate mode on  
simulate the boat moving off course.  
2 Demo  
Simulates a boat moving along a route and  
automatically displays different Instrument  
functions. The options required for Demo are:  
!
WARNING  
Never have simulate mode on when the  
Instrument is navigating on the water.  
Speed: The simulated boat speed to use.  
Route: The route to follow.  
Mode  
There are two choices for Mode:  
1 Normal  
Simulates the boat moving from the selected  
start point at the given speed and heading.  
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20 Installation  
!
WARNING  
Ensure that any holes cut are in a safe position and will not weaken the boat’s structure. If in  
doubt, consult a qualified boat builder.  
CAUTION  
Do not mount any part where it can be used as a hand hold, where it might be submerged or  
where it will interfere with the operation, launching or retrieving of the boat.  
To help ensure proper operation, do not mount any part or cable within 0.5 m (20”) of the plane  
of a radar antenna or within 1 m (3 ft) of a compass or source of electrical noise, such as engines,  
fluorescent lights, and power inverters.  
When fitting a cable, do not crush or strain the cable. Secure the cable at regular intervals. Ensure  
no connectors or exposed terminals are in wet area.  
If the cables supplied are too long, do not shorten the cable; instead coil the cable. Most cables  
can be extended with Northstar extension cables. Do not fit more than one extension cable.  
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20-1 Installation: What else comes with my M121/M84?  
Northstar GPS 124 Antenna  
GPS 124 Antenna bottom cone  
GPS 124 Antenna gasket  
GPS 124 mounting kit  
Sun cover for display unit  
Note: Place over display when not in use  
Front Bezel  
Note: Fit this after installing the display unit  
Power cable  
Mounting bracket and locking knobs  
Bracket mounting screws  
(5 x14 Gauge self tapping screws)  
Flush mounting screws  
(4 x 8 Gauge self tapping screws)  
Northstar wallet  
Contains the following items:  
Flush mounting template  
LCD cleaning cloth  
Warranty card  
Quick start guide  
CD manual  
M121/M84 Installation and operation manual  
GPS 124 Antenna Installation and operation manual  
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20-2 Installation: Options and Accessories  
Replacement paddle wheel.  
DSC VHF radio: Tracks other boats with  
GPS receivers and DSC radios and displays  
barometric pressure (see section 20-10).  
C-MAP™ NT-MAX, NT+ or NT chart SD cards.  
Northstar NavBus junction boxes simplify  
wiring, particularly if several instruments are  
connected. For more information, see the  
NavBus Installation Manual.  
SmartCraft: With one or two SmartCraft  
capable Mercury petrol/gasoline engines, the  
Instrument can display engine data and trim  
and can control troll speed (see section 20-8).  
Optional sensors and instruments  
Radar: For radar functions. A Northstar 2 kW, 4  
kW or 6 kW radar system must be installed (see  
section 20-9).  
External alarms: Lights or sounders in the  
boat to sound alarms through the boat (see  
section 20-4).  
Other instruments: The Instrument can  
receive data from other instruments and send  
data to other instruments by NavBus or NMEA  
(see sections 20-11 and 20-12).  
GPS or DGPS antenna: For GPS navigation,  
see section 20-5.  
Sonar transducer: For depth sounding and  
fish finding, see section 20-6.  
Please consult your Northstar dealer for more  
information.  
Fuel sensors: For fuel functions. The  
Instrument can use these optional fuel flow  
sensors, fitted to one or two engines:  
Northstar petrol/gasoline sensors (see  
section 20-7)  
SmartCraft fuel sensors (see section 20-8)  
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Connections  
q Sonar  
w Video in Video Input  
(Analogue composite  
Sonar Transducer  
M121  
[NTSC-PAL])  
e Comms Not Used  
r GPS  
Northstar 124 GPS Antenna  
t Fuel/Nav - Northstar Fuel TXD  
- SmartCraft Gateway  
y Radar  
Northstar Radar Processor  
u Power/data cable  
Wire  
Function  
Black  
Ground: power negative,  
NMEA ground (Connect both  
black wires to ground)  
Not Used  
NMEA out  
NavBus-  
Brown  
White  
Blue  
1
2
3
4
5
6
7
Red  
Positive power in, 10  
to 35 V DC  
Orange  
Yellow  
NavBus+  
Auto power - Connect to red  
wire (positive power in) to  
enable Auto power No Auto  
power - Leave disconnected  
or connected to Black  
wire (ground)  
Green  
External Alarm output or light  
out, switches to ground  
during alarm condition,  
200 mA maximum.  
20-3 Installation: The display unit  
Start by selecting a suitable mounting position  
for the M121/M84 display unit:  
For optimum performance and reliability  
consider mounting the unit where it will not  
be unnecessarily exposed to direct sunlight,  
water and protected from other physical  
damage which could occur during rough  
sea passages.  
Consider the best possible position for  
viewing and operating the M121/M84. This  
will generally be a relatively shaded area free  
from obstructions.  
If bracket mounting chose a flat area where  
the display will not be subjected excessive  
vibration.  
At least 4” (100 mm) away from the compass,  
at least 12” (300 mm) away from any radio  
transmitter and at least 4 ft (1.2 m) away  
from any antenna.  
Select an area with adequate clearance for  
cabling and access to the power source.  
Before drilling any holes ensure that  
the drill area is free from cables or other  
obstructions.  
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There are two mounting arrangements:  
Note: the 5 x 14G self tapping screws are for  
bracket mounting only.  
Flush Mounting the M121/M84  
1. Attach the flush mounting template to the  
selected mounting position using adhesive  
tape.  
8. To finish off the installation firmly clip the  
front bezel in place.  
2. Drill a pilot hole for each of the hole saw  
cuts shown on the template before cutting  
the larger hole with the hole saw.  
Bracket Mounting the M121/M84  
An alternative to flush mounting the M121/M84  
is to bracket mount the unit. This method has  
the advantage that the display can be easily  
removed when it is not in use. The display may  
be tilted for best possible viewing angle when  
bracket mounted.  
3. Next cut all the way around the inside of the  
cut-out line with a saw to remove the waste  
material shown on the template.  
4. Check that the unit fits correctly in the cut  
out area. Adjust the fit with a file if required.  
Note: The mounting bracket does not allow for  
rotation of the unit to the left and right.  
5. Select a 2-3.5 mm 1/8” drill bit depending  
on hardness of material to drill. Smaller  
diameter holes will be needed for soft  
woods and larger diameter pilot holes will  
be required if mounting to hard materials  
such as fiberglass (we recommend 3.5 mm  
(1/8”) for fiberglass and Aluminum).  
1. Use the mounting bracket as a template to  
mark the 5 positions of the screw holes.  
2. Select a suitable drill bit (note: larger  
diameter pilot holes may be required if  
mounting to fiberglass) and drill 5 pilot holes  
in the marked positions.  
With the selected drill bit drill the 4 pilot  
holes for the 8 gauge screws used to attach  
the unit. These are indicated on the corners  
of the mounting template.  
3. Secure the mounting bracket using the 5 x  
14G self tapping screws.  
4. Slide the M121/M84 into the mounting  
bracket and secure in place with the bracket  
knobs.  
6. Connect all cables to the rear of the unit  
before placing the unit into the console.  
5. To finish off the installation firmly clip the  
front bezel in place.  
7. Firmly secure the unit in place with the 4 x 8  
gauge self tapping screws.  
Bezel  
M121/M84  
M121/M84  
Knob  
14G self tapping screws  
Mounting bracket  
8 gauge screws  
Dash  
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20-4 Installation: Power/data cable  
The power/data cable has a black locking collar and flying leads.  
1
Wire the Instrument for auto power to have the Instrument turn on with the boat’s ignition switch  
or to record engine hours or if the Instrument must add up the total fuel used (for example if  
Northstar petrol/gasoline fuel sensors are installed or if SmartCraft is installed without fuel tank  
level sensors). Otherwise wire for basic power (for more information, see section 2-2).  
Basic power  
Power/data cable  
Red  
Black  
Fuse 2A  
Yellow  
Main switch  
Black  
12/24 V DC  
Auto power  
When wired for Auto Power On the unit will turn on when the ignition switch is on, if you would like  
the unit to turn off when the ignition switch is off then set the unit for Auto Power Off (see section  
2-2 and 17-1)  
Power/data cable  
Ignition  
Yellow  
Black  
Fuses 2A  
Ignition switch  
Main switch  
12/24 V DC  
Red  
Black  
2
3
Wire any external alarm beepers or lights. The alarm output switches to ground to sound the  
alarm. If the current is more than 200 mA, fit a relay.  
Connect the power/data cable to the black display unit connector; turn the collar to lock the  
connector.  
Power/data cable  
Red  
Black  
Green  
External beepers or  
lights  
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20-5 Installation: GPS antenna  
WAAS covers all of the USA and most of Canada.  
To use WAAS, the GPS antenna must have  
a clear view of the sky towards the equator.  
EGNOS will cover most of Western Europe.  
Selecting an antenna  
Fit one of these GPS antennas:  
Normally use the GPS antenna supplied.  
An optional differential beacon DGPS  
antenna to give enhanced accuracy within  
range of land based differential beacons  
in areas where WAAS or EGNOS are not  
available. Such a DGPS antenna has both a  
GPS receiver and a beacon receiver, and it  
automatically applies the beacon correction  
to the GPS position.  
Restart GPS:  
Restarts the GPS receiver, satellite reception will  
be lost until the receiver completes its restart  
and acquires the satellites.  
ENTER  
Select restart GPS and press  
A compatible GPS or DGPS instrument or  
antenna connected by NavBus (see section  
20-10) or NMEA (see section 20-11). In this  
case, the Instrument does not need its own  
antenna.  
!
WARNING  
MOB will not work if the Instrument does  
not have a GPS fix.  
Note:  
To configure the Instrument for different  
antenna options, see section 19-4.  
Installing an antenna  
If an external antenna is required, install the  
antenna and fit the antenna cable back to  
the display unit. Follow the instructions in  
the manual supplied with the antenna. Fit an  
optional Northstar extension cable if required.  
For more information, contact your Northstar  
dealer.  
DGPS Source:  
During setup, configure the Instrument for the  
chosen antenna, see section 19-4.  
Enables or disables the satellite based DGPS  
correction (see section 8). The options are  
None or WAAS/EGNOS. Do not Enable  
WAAS/EGNOS outside their coverage areas  
or the accuracy of the position might be  
degraded.  
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20-6 Installation: Sonar transducer  
Sonar cable  
!
WARNING  
Blue  
Do not install plastic through hull  
transducers in solid wooden hulls. Leakage  
through the hull may result.  
Connect the transducer to the blue Instrument  
connector; tighten the locking collar.  
Do not install bronze transducers in metal  
hulls. This will cause electrolytic corrosion  
that may result in damage to the hull or  
transducer.  
During setup  
a) set Sonarto (see section 19-1)  
b) set up the sonar options (see section 19-3)  
20-7 Installation: Northstar petrol/gasoline sensors  
Fit the optional petrol/gasoline fuel kit following  
the instructions supplied with the kit.  
During setup:  
a) set the fuel data (see section 19-6)  
Note:  
SmartCraft engines have fuel flow sensors,  
therefore Northstar fuel sensors are not  
required as well.  
White  
Fuel sensor cable  
For dual engines, fit two kits.  
Wire the Instrument for auto power (see  
section 20-4).  
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20-8 Installation: SmartCraft  
If the boat has one or two SmartCraft capable  
Mercury petrol/gasoline engines, connect the  
Instrument to the SmartCraft engines with  
an optional SmartCraft gateway. The display  
unit can display engine data and trim and can  
control troll speed.  
SmartCraft Gateway  
White  
During setup enter the SmartCraft setup data.  
For information on installing, setting up and  
using SmartCraft, see the SmartCraft Gateways  
Installation and Operation Manual.  
Note:  
Fit a single gateway for single engines and a  
dual gateway for dual engines.  
SmartCraft engines have fuel flow sensors,  
therefore Northstar fuel sensors are not  
required as well.  
If the fuel tank does not have SmartCraft  
level sensors, wire for auto power (see  
section 20-4).  
20-9 Installation: Radar  
Install the Northstar radar as described in the  
Installation Manual supplied with the radar.  
Carefully read the important safety and warning  
information and also the location and wiring  
guidelines BEFORE installing the radar.  
Radar cable  
RADAR  
Set up the radar as described in section 19-4.  
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20-10 Installation: Other NavBus instruments  
NavBus is Northstar’s system for connecting  
instruments together to interchange data  
and share transducers. When instruments are  
connected by NavBus:  
Fish forecaster: a prediction based on  
changes in barometric pressure  
DSC/Buddy Track: (see section 17)  
Receive data from an optional GPS or  
GPS/DGPS source.  
If the units, alarms or calibration are  
changed in one instrument, then the  
values will automatically change in all other  
instruments of the same type.  
Send data to optional Northstar instruments,  
for example to a repeater.  
During setup for NavBus instruments, set  
NavBusto and assign the instrument a  
NavBus groupnumber (see section 19-12)  
Each instrument can be assigned to a group  
of instruments. If the backlight is changed in  
an instrument in group 1, 2, 3 or 4 then the  
backlight will automatically change in the  
other instruments in the same group.  
Black  
Power/data cable  
Orange  
If the backlight is changed in an instrument  
in group 0 then no other instruments are  
affected.  
Blue  
If an alarm sounds, mute it by clearing the  
alarm on any instrument which can display  
that alarm.  
NavBus wires to other  
NavBus instruments  
NavBus and the Instrument  
The M121/M84 can:  
20-11-1 Installation: Northstar VHF radio  
Fit and set up the optional Northstar VHF  
radio (with NavBus functionality) following the  
instructions supplied with the radio.  
Display wind speed and direction from an  
optional Northstar Wind instrument  
Receive and display depth from an optional  
Northstar depth instrument.  
Black  
Power/data cable  
Orange Blue  
Receive and display boat speed and water  
temperature from a paddlewheel sensor on  
an optional Speed instrument.  
Blue  
Grey  
Radio data cable  
Receive data from an optional Northstar  
VHF radio (with NavBus functionality). The  
M121/M84 can display:  
Baro: barometric pressure  
Baro history: barometer history  
Weather: a predication, based on changes  
in barometric pressure  
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20-11 Installation: Other NMEA instruments  
NMEA is an industry standard for  
interconnecting instruments. It is not as flexible  
or as easy to install as NavBus.  
The Instrument can:  
For information on sending NMEA data to the  
Instrument, see your Northstar dealer.  
During setup to send NMEA data to other  
instruments, set NMEA outto and specify  
the NMEA datato send (see section 19-12).  
Receive and display wind speed and  
direction from an optional compatible wind  
instrument.  
Power/data cable  
White NMEA out  
Receive and display depth, paddlewheel  
boat speed and water temperature from an  
optional compatible instrument.  
Black NMEA ground  
White  
Black  
Receive data from an optional compatible  
GPS or GPS/DGPS source.  
Send GPS position and other navigation  
data to an autopilot or other instrument.  
An autopilot requires APB, APA and VTG  
sentences (see section 19-12).  
White NMEA in  
(requires Special Fuel Cable)  
20-12 Installation: Setup and test  
Setup and test  
5
6
Enter setup data to set up the Instrument  
to your requirements and to set up any  
optional sensors or instruments (see section  
19).  
1
Put a blanking cap on any unused connector  
on the back of the display unit. Ensure all  
connectors are plugged in and the display  
unit is in place.  
At the satellite window, check that it picks  
up GPS satellites. Wait for the GPS receiver  
to start up and the fix type to change from  
‘Acquiring’ to ‘GPS fix’. This should take less  
than two minutes (see section 8).  
2
If the display unit is bracket mounted, adjust  
tilt and rotation for best viewing and hand  
tighten the knob.  
3
4
Insert any required C-MAP chart card (see  
section 1-3).  
7
Go on a test run to check that the navigation  
equipment works correctly, particularly  
when a radio transmitter or radar is used.  
Turn the instrument on (see section 2-2).  
When the Instrument is turned on for the  
first time, it displays an installation menu:  
i
Select the language to use.  
ii Change the data if necessary (see section  
2-1)  
iii When the setup data is correct, press  
ESC  
.
This data can be changed later  
(see section 19).  
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Appendix A - Specifications  
GENERAL  
Depth acquisition time from startup:  
Typically 2 seconds at 30 m (100 ft)  
Temperature:  
M121 Size: 256 mm (10.08“) H x 385 mm (15.16“) W x  
78.5 mm (3.09“) D. Allow 3 mm clearance on each  
side for dust cover.  
Range 0° to 37.7°C (32° to 99.9°F)  
Resolution of 0.1° unit.  
M84 Size: 190 mm (7.48“) H x 285 mm (11.22“) W x 76.8  
mm (3.02“) D. Allow 3 mm clearance on each side  
for dust cover.  
Speed (from paddlewheel transducer):  
1 to 96.6 kph (57.5 mph, 50 kn).  
FUEL COMPUTER  
M121 Display: 307 mm (12.1”) diagonal, TFT color, 800  
x 600 pixels.  
(Optional fuel sensor(s) required)  
Engine types:  
M84 Display: 213.4 mm (8.4”) diagonal, TFT color, 800  
x 600 pixels.  
Backlight: Display and keys  
Supply voltage: 10.5 to 32 V DC.  
Supply current: at 13.8 V  
Outboard carburetted two stroke and EFI  
petrol/gasoline engines: 50 to 300 hp.  
Outboard four stroke petrol/gasoline engines: 90  
to 300 hp.  
350 mA min - no backlighting.  
1A max - full backlighting.  
Inboard petrol/gasoline engines: 70 to 400 hp.  
Flow rate:  
External beeper or light output: Switched  
to ground to sound alarm, 30 V DC, 200 mA  
maximum.  
Minimum: 5 litres per hour (1.3 U.S. gallons per hr).  
Maximum: 130 litres per hour (34 U.S. gallons per hr).  
COMMUNICATIONS  
Operating temperature: 0° to 50°C (32° to 122°F)  
ALARMS:  
NavBus  
User set: Arrival radius, anchor, XTE, danger, too  
shallow, too deep, fish, temperature, temperature  
rate, low battery, low fuel (optional), loss of DGPS  
fix, radar guard zone, dangerous AIS vessels.  
Connection to other Northstar instruments.  
NMEA: NMEA 0183 ver 2 4800 baud  
Inputs from compatible instruments:  
BWR, DPT, GGA, GLL, GSA, GSV, HDG, HDM, HDT,  
MTW, MWV, RMC, VHW, VTG and DBT  
GPS NAVIGATION  
Chart card: C-MAP™ SD Card (NT-MAX, NT+ or NT)  
User card: SD Card  
Outputs, for compatible instruments:  
APA, APB, BWR, DBT, DPT, GGA, GLL, GSA, GSV, RMB,  
RMC, MTW, VHW, VLW, VTG, XTE  
Waypoints: Up to 3000, with default or user-defined  
alphanumeric names up to eight characters.  
STANDARDS COMPLIANCE  
EMC:  
Routes: 25 Routes, with up to 50 points each  
Tracks: By time or distance, one track of 2000 points  
USA: FCC Part 15 Class B.  
Europe: (CE) EN301843-1  
New Zealand and Australia: (C Tick) IEC60945  
and four of 500 points.  
Chart datums  
121 Chart datums (see next page)  
One user-defined map shift.  
Environment: IPx6/IPx7/CFR46 (with card holder and  
connections in place)  
Chart scale: 0.05 to 4096 nm for chart (chart  
Video  
dependent) down to 0.01 nm in plotter mode.  
75Ω BNC Connector. Most PAL and NTSC formats  
supported. (PAL BGHI, PAL N, Combination PAL N,  
PAL M, NTSC M, NTSC N, NTSC 4.43, NTSC-Japan  
and SECAM)  
SONAR FISHFINDING  
(Optional sonar transducer required)  
Depth range: 1 m (3 ft) to 1000 m (3300 ft )  
Sonar output:  
Power: Variable, up to 600/1000 W RMS  
Dual frequency: 50 khz and 200 kHz  
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Physical Dimensions  
Northstar M121  
M121  
Northstar M84  
M84  
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List of datums  
Adindan  
Afgooye  
Anna 1 Astro 1965  
ARC 1960  
Astro DOS 71/4  
Australian Geodetic 1966  
Bellevue (IGN)  
Bogota Observatory  
Campo Inchauspe 1969  
Cape Canaveral  
Chua Astro  
AIN EL ABD 1970  
Antigua Island Astro 1943  
Ascension Island 1958  
Astro Station 1952  
Australian Geodetic 1984  
Bermuda 1957  
Bukit Rimpah  
Canton Astro 1966  
Carthage  
Co-ord. Sys.1937 Estonia  
Deception Island  
Easter Island 1967  
Fort Thomas 1955  
Graciosa Base Sw 1948  
GUX 1 Astro  
American Samoa 1962  
ARC 1950  
Astro Beacon ‘E1945  
Astro Tern Island (Frig) 1961  
Ayabelle Lighthouse  
Bissau  
Camp Area Astro  
Cape  
Chatham Island Astro 1971  
Corrego Alegre  
Djakarta (Batavia)  
European 1950  
Gan 1970  
Guam 1963  
Herat North  
Hong Kong 1963  
Indian 1954  
Dabola  
DOS 1968  
European 1979  
Geodetic Datum 1949  
Gunung Segara  
Hermannskogel  
Hu-Tzu-Shan  
Hjorsey 1955  
Indian  
Indian 1975  
Indian 1960  
Indonesian 1974  
ISTS 073 Astro 1969  
Kerguelen Island 1949  
L. C. 5 Astro 1961  
Luzon  
Ireland 1965  
Johnston Island 1961  
Kertau 1948  
Leigon  
M’Poraloko  
ISTS 061 Astro 1968  
Kandawala  
Kusaie Astro 1951  
Liberia 1964  
Mahe 1971  
Massawa  
Minna  
Merchich  
Montserrat Island Astro 1958  
Midway Astro 1961  
Nahrwan Masirah Is. Oman  
Naparima, BWI  
North Sahara 1959  
Old Hawaiian  
Nahrwan United Arab Emirates Nahrwan Saudi Arabia  
North American 1927 North American 1983  
Observatorio Meteorolog. 1939 Old Egyptian 1907  
Oman  
Ord. Survey Great Britain 1936  
Point 58  
Provis. South American 1956  
Pulkovo 1942  
Reunion  
Pico de las Nieves  
Pointe Noire 1948  
Provis. South Chilean 1963  
Qatar National  
Pitcairn Astro 1967  
Porto Santo 1936  
Puerto Rico  
Qornoq  
Rome 1940  
S-42 (Pulkovo 1942)  
Sapper Hill 1943  
Sierra Leone 1960  
South Asia  
Tokyo  
Voirol 1874  
Santo (DOS) 1965  
Schwarzeck  
S-JTSK  
Tananarive Observatory 1925  
Tristan Astro 1968  
Voirol 1960  
Sao Braz  
Selvagem Grande 1938  
South American 1969  
Timbalai 1948  
Viti Levu 1916  
Wake Island Astro 1952  
Yacare  
Wake-Eniwetok 1960  
Zanderij  
WGS 84  
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Appendix B - Troubleshooting  
This troubleshooting guide is written with  
the assumption that the user has read and  
understood the relevant sections in this manual.  
Repairs to the product may only be carried out  
by a service centre approved by Northstar. If the  
product must be sent into a service centre for  
repair, it is essential to send in the transducer(s)  
at the same time.  
It is possible in many cases to solve difficulties  
without having to send the display unit back to  
the manufacturer for repair. Please follow this  
troubleshooting section before contacting the  
nearest Northstar dealer.  
More information can be found on our Website:  
www.northstarnav.com.  
There are no user serviceable parts. Specialized  
methods and testing equipment are required  
to ensure that the display unit is reassembled  
correctly and is waterproof. Users who service  
the product themselves will void the warranty.  
B-1 General problems  
1-1 The Instrument won’t turn on:  
f
Check for corrosion on the power cable  
connector and clean or replace if required.  
a
The Instrument is designed to operate  
on a 12/24 volt battery system, where the  
voltage may vary from 10.5 to 32 volts. If an  
excessive voltage is supplied, a fuse will be  
tripped, turning the display unit off. Check  
the fuse.  
g
Check fuses that are placed in line with the  
power cable. A fuse can be blown despite  
appearing to be good or the fuse may be  
corroded. Test the fuse or replace it with a  
fuse known to be good.  
1-2 The Instrument won’t turn off:  
b
c
Check that the power cable connector at the  
back of the display unit is securely plugged  
in and the collar is locked in place. The collar  
must be secure for watertight connection.  
The Instrument may have been wired for  
Auto power. In this case, the Instrument  
cannot be turned off while the ignition  
power is on (see section 2-2).  
Measure the battery voltage while the  
battery is under load - turn on some  
lights, radio or other electrical equipment  
connected to the battery. If the voltage is  
less than 12 volts:  
1-3 If the Instrument beeps when turned  
on but nothing is displayed:  
The Instrument may be operating, but the  
backlight settings may have been set too  
low (see section 2-3).  
-
the battery terminals or wiring on the  
terminals may be corroded.  
1-4 The wrong language is displayed:  
-
the battery may not be charging  
correctly or may need replacing.  
See section 19-1.  
d
e
Inspect the power cable from end to end  
for damage such as cuts, breaks, squashed  
or trapped sections.  
Check power wiring (see section 18-4).  
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B-2 GPS navigation problems  
2-1 No GPS fix or long time to get fix at  
startup:  
2-5 The time or date on satellite display is  
wrong or off:  
a
May occur occasionally if the antenna does  
not have a clear view of the sky. The satellite  
positions are constantly changing.  
a
No GPS fix.  
b
In simulate mode. Turn simulate mode off  
(see section 19-16).  
b
Antenna cable not connected to display  
unit.  
c
Local time offset is wrong (see section 17-12).  
The Local Time Offset must be changed  
when daylight saving time starts or ends.  
2-2 Instrument GPS position different from  
true position by more than 10 m (33 ft):  
2-6 Autopilot not responding to  
Instrument; no NMEA output:  
a
b
c
Instrument in simulate mode. Turn simulate  
mode off (see section 19-16).  
a
NMEA output disabled or the required  
NMEA sentences are not turned on. Check  
NMEA settings (see section 19-12).  
The normal error in GPS position will exceed  
10 m (33 ft) for about 5% of the time.  
Under special circumstances the US  
Department of Defence may introduce a  
deliberate and changing error in the GPS  
positions of up to 300 m (1000 ft).  
b
Check that the instrument is connected  
correctly.  
2-7 No DGPS fix or loss of DGPS fix:  
a
To receive a DGPS fix, WAAS/EGNOS must be  
enabled or an optional DGPS antenna fitted  
(see section 8).  
2-3 Instrument position different from  
same position on local charts:  
a
b
c
Instrument in simulate mode. Turn simulate  
mode off (see section 19-16).  
b
c
With WAAS/EGNOS: Boat out of coverage  
area (see section 8).  
Incorrect chart datum. Select the correct  
chart datum (see section 19-2).  
With WAAS: GPS antenna does not have  
a clear view of the horizon towards the  
equator.  
Map shift has been applied wrongly. Clear  
map shift, then reapply if necessary (see  
section 19-2).  
b
With beacon DGPS: boat out of range of a  
DGPS beacon.  
2-4 Can not see boat on chart:  
ESC  
Press  
to switch to centre on boat  
mode (see section 3-2-1).  
B-3 Fuel consumption problems  
3-1 Fuel used or remaining seem  
inaccurate:  
c
The Set remainingfuel value must  
be reset after every refuelling (see section  
113-1).  
a
Instrument is not wired for auto power (see  
section 20-4).  
d
The fuel tank may not refill to the same  
capacity each time due to air pockets.  
This is particularly noticable with underfloor  
tanks.  
b
In rough seas, fuel may surge back and forth  
through the fuel transducer, resulting in  
incorrect readings. Try installing a one-way  
valve between the fuel transducer and the  
fuel tank.  
e
Fuel transducers wear out over time and  
should be replaced after every 5000 litres of  
fuel.  
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3-2 Flow indicates no fuel or low fuel:  
3-3 A twin engine installation shows only  
one flow rate:  
a
Check that the number of engines is set to 1  
(see section 19-6).  
a
Check that the number of engines is set to 2  
(see section 19-6).  
b
Check that the fuel cable connectors are  
securely plugged in and the collar is locked  
in place. The collar must be locked in place  
to give a watertight connection.  
3-4 Erratic Fuel Flow readings:  
a
The fuel flow transducer may have been  
mounted too close to the fuel pump or may  
be subject to excessive vibration. Refer to  
the installation instructions supplied with  
the fuel transducer.  
c
A fuel transducer may be clogged. If so,  
remove the transducer from the fuel line  
and gently blow through it in the opposite  
direction to the fuel flow.  
b
c
Check for leaks in the fuel line or in the fuel  
pickup in the tank.  
A fuel filter between the fuel transducer and  
the fuel tank must be installed as per the  
fuel installation guide. Failure to do so will  
void the warranty.  
The Flow filtervalue is not suitable for  
the engine. Check that the value is not set  
to zero, then try increasing the value until a  
steady flow rate is shown (see section 19-6).  
d
e
Inspect the fuel cable from end to end for  
damage such as cuts, breaks, trapped or  
squashed sections.  
3-5 There is no reading for fuel economy:  
a
The boat must be travelling through the  
Check that the fuel filter is clean.  
water to generate an Economyreading.  
b
Check that the paddlewheel on the  
transducer is spinning freely and that the  
two magnets in the paddlewheel are still in  
place.  
B-4 Sonar fishfinding problems  
4-1 The Instrument operates erratically:  
e
f
Ensure the back of the bottom surface of  
the transducer is slightly lower than the  
front and the front is as deep in the water as  
possible in order to minimize the generation  
of bubbles through cavitation. (See the  
Transom Transducers Installation Guide)  
a
Check that the transducer does not have  
debris (e.g. weed, plastic bag) caught  
around it.  
b
The transducer may have been damaged  
during launching, running aground or  
while underway with debris etc. If the  
transducer has been impacted, it may have  
been kicked up on the bracket. If it is not  
physically damaged, reset the transducer  
back to its original position. (See the  
Check the transducer and power cable  
connectors at the back of the display unit  
are securely plugged in and the collars are  
locked in place. The collars must be secure  
for watertight connection.  
Transom Transducer Installation Guide.)  
g
h
Inspect the power cable from end to end for  
damage such as cuts, breaks, squashed or  
trapped sections.  
c
When the transducer is less that 2 ft (0.6 m)  
from the bottom, the depth readings may  
become inconsistent and erratic.  
Ensure there is not another fishfinder or  
depth sounder turned on, which may  
interfere with this Instrument.  
d
Manual Gain may be set too low, which may  
cause weak bottom echo or no fish signals. If  
in Manual Gain, try increasing the Gain.  
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i
Electrical noise from the boat’s engine or  
an accessory may be interfering with the  
transducer(s) and/or the Instrument. This  
may cause the Instrument to automatically  
decrease the Gain unless using Manual Gain.  
4-4 Bottom echo disappears or erratic  
digital reading while the boat is moving:  
a
Ensure the back of the bottom surface  
of the transducer is slightly lower than  
the front and the front is as deep in the  
water as possible in order to minimise the  
generation of bubbles through cavitation.  
(See the Transom Transducers Installation  
Guide, for more information.)  
The Instrument thus eliminates weaker  
signals such as fish or even the bottom  
from the display. This may be checked  
by switching off other instruments,  
accessories (e.g. bilge pump) and the  
motor until the offending device is  
located. To stop problems from electrical  
noise, try:  
b
The transducer may be in turbulent water.  
Air bubbles in the water disrupt the echoes  
returned, interfering with the Instrument’s  
ability to find the bottom or other targets.  
This often happens when the boat is  
-
re-routing the power and transducer  
cable(s) away from the boat’s other  
electrical wiring.  
reversed. The transducer must be mounted  
in a smooth flow of water in order for the  
Instrument to work at all boat speeds.  
-
routing the display unit’s power cable  
c
Electrical noise from the boat’s motor can  
interfere with the Instrument. Try some  
suppression spark plugs.  
directly to the battery with an in-line fuse.  
4-2 Bottom is not displayed:  
a
The Instrument may have Manual Range  
selected and the depth may be outside  
the range value selected. Either change  
the Instrument to Auto Range or select  
another depth range (see section 8-5).  
4-5 There is a double bottom trace  
displayed:  
a
The boat may be in an area that generates  
shadows (see section 9-2).  
b
In shallow water, the echoes may bounce.  
Reduce the gain setting (see section 9-6)  
and/or reduce the sonar pulse power (see  
section 19-3).  
b
The depth may be outside the Instrument’s  
range. While in Auto Range, the display unit  
will display “--.-” to indicate that there is no  
bottom detected. A display of the bottom  
should reappear when in shallower water.  
c
Decrease the Range.  
4-3 The bottom is displayed too far up  
the screen:  
The Instrument may have Manual Range  
selected and the selected Range value is  
too high for the depth. Either change the  
Instrument to Auto Range or select another  
depth range (see section 8-5)  
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B-5 Radar problems  
5-1 Radar overlay doesn’t appear on the  
chart screen  
5-4 Radar shows false echoes and/or  
background noise  
False echoes and/or background noise can  
be produced if the radar sensitivity is too  
high.  
a
Ensure that your boat is shown on the radar  
window. If it is, but the radar overlay still  
isn’t shown, try zooming in on the charted  
area. (The charted area may be outside the  
maximum range of the radar).  
a
Try using the Auto setting for the radar gain  
mode (see 19-4). If this doesn’t work, or if the  
radar gain mode is already set to Auto, use  
the radar gain setting to reduce the radar  
sensitivity  
b
The threshold or transparency settings for  
the radar overlay are not correct (see 18-6).  
5-2 Radar shows arcs and/or shadows  
5-6 Radar shows multiple echoes off the  
same object  
Side lobe patterns often appear as an arc or  
a broken arc. Shadows are blind spots.  
Multiple echoes off the same object are  
most likely to occur when you are close  
to a large target, and are usually only a  
temporary nuisance.  
If the radar is installed at a suitable height  
and in a suitable location on your boat,  
side lobe patterns and shadows caused by  
obstructions such as funnels or masts will be  
minimized.  
5-7 Radar shows random or grouped dots  
Rain clutter often appears as random dots  
that can merge into badly-defined echoes  
on the radar window. The random signals  
are returned from rain, hail, sleet, or snow  
and can result in a confusing display  
If you are having problems with these, you  
may need to relocate your radar. Consult the  
Installation Guide for your radar model for  
advice.  
5-3 Radar shows different patterns on  
each sweep  
5-8 Radar shows random signals in centre  
Sea clutter usually appears as confusing,  
random signals around your boat. High  
waves will produce the maximum amount of  
sea clutter.  
Interference patterns always appear in a  
different place with each sweep. They can  
be randomly scattered bright dots or dotted  
lines that extend from the centre to the  
edge of the radar window, often producing  
a spiral effect. Generally, the stronger the  
interference, the wider the interference lines.  
You can optimize your radar window to  
reduce the effects of sea clutter (see section  
18-6-4).  
a
Use the interference rejection feature to  
reduce interference patterns, and the width  
of the interference lines (see 19-4).  
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Appendix C Glossary and navigation data  
Air temp - Air temperature (requires Northstar  
Goto - A simple way of navigating straight to a  
721 VHF radio).  
waypoint or to the cursor position (see section  
3-1).  
Alarm status - Shows the symbol (see section  
19-10) for each alarm that is on. The symbol  
is normally black and turns red if the alarm  
triggers.  
GPS - Global Positioning System. A satellite-  
based navigation tool (see section 7).  
Leg - The straight segments of a route between  
waypoints. A route with four waypoints has  
three legs.  
Attention Area - An important area on a chart,  
such as a restricted anchorage or a shallow area  
(see section 19-2).  
MMSI - Maritime Mobile Service Identity.  
Unique identification number for a vessel, for  
use in Digital Selective Calling.  
AIS - Automatic Identification System. A System  
where vessel information (location, course,  
speed, etc.) is broadcast by VHF radio, for use  
by other vessels in navigation and collision  
avoidance.  
MOB - Man overboard.  
MOB function - Starts navigating back to  
the place where someone fell overboard (see  
section 2-4).  
Bathymetric line - A depth contour line on  
the chart.  
NavBus - A way of connecting Northstar  
instruments together to share data (see section  
20-10).  
Chart card - A plug-in card that stores chart  
data for a region (see section 1-3).  
C-MAPchart card - See Chart card.  
NMEA - National Marine Electronics  
C-MAPuser card - See User card.  
Association.  
CPA - Closest Point of Approach. The closest  
distance two vessels will come to each other  
based on their current course and speed.  
NMEA 0183 - A standard for interfacing marine  
electronic devices (see section 20-11).  
Radar guard zone - An area around the  
boat, set up by the operator and defined by  
distance and bearing. If an object (e.g. another  
boat) enters the radar guard zone, an alarm is  
activated.  
Cursor - A symbol on the display (see  
section 3-2).  
DGPS - Differential Global Positioning System.  
A navigation tool based on GPS with some  
errors corrected (see section 7).  
Rain clutter - Heavy rain or snow can cause  
interference with the radar image.  
DSC - Digital Selective Calling. A feature  
of marine radios enabling communication  
between specific vessels, as well as distress  
alerts.  
Range (radar) - The distance between the  
centre of the radar image and the outer range  
ring. The scale is shown in the top left corner of  
the radar window.  
DTN - Distance to the next position the  
M121/M84 is navigating to, either a waypoint or  
the cursor.  
Range rings - Concentric circles extending  
from your boat (usually at the centre of the  
radar window) and used to estimate distances  
to objects. The scale is shown in the top left  
corner of the radar window.  
Fish forecaster - An estimate of the likelihood  
of catching fish based on barometric pressure.  
The more fishes that show the higher the  
likelihood (requires Northstar 721 VHF radio).  
Route - Two or more waypoints linked in  
sequence to form a course for the boat (see  
section 7).  
Gear - The gear the engine is in (requires  
SmartCraft).  
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SmartCraft - A feature of Mercury Marine  
engines for monitoring engine performance.  
UTC - Universal Time Coordinated or  
Coordinated Universal Time, which is a standard  
world time, formerly called Greenwich Mean  
Time (GMT).  
TCPA - Time to Closest Point of Approach.  
Time until the closest point of approach for two  
vessels.  
VHF - Very High Frequency. The frequency  
range used by marine radios.  
Sea clutter - Rough seas can cause  
interference with the radar image.  
Waypoint - A position that you can set on the  
Instrument chart, for example a fishing spot or a  
point on a route (see section 5).  
Sonar status - A summary of sonar settings.  
TTN - Time to the next position the M121/M84  
Weather - An estimate of the weather based  
on barometric pressure (requires Northstar 721  
VHF radio).  
is navigating to, either a waypoint or the cursor.  
User card - A plug-in card that stores  
waypoints, routes and tracks (see section 1-2).  
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Navigation data  
BRG Bearing to Destination: Bearing to the destination from the boat.  
BRG Bearing to cursor: Bearing to cursor from boat (cursor mode, see section 3-2-1)  
CDI  
Course Deviation Indicator: When the boat is navigating to a point, the chart and highway windows  
show a parallel line on either side of the plotted course. These two lines are called the Course Deviation  
Indicator (CDI) lines. The distance from the plotted course to a CDI line is the CDI scale.  
Set the CDI scale (see section 17-2) to the maximum distance that the boat should deviate from the  
plotted course. The chart and highway windows show the CDI lines, which are like a highway over the  
water where the boat will move. The windows show how far the boat has deviated from the plotted  
course and if the boat is approaching a CDI line. If the XTE alarm is enabled (see section 17-8) an alarm  
will sound if the boat reaches a CDI line.  
COG Course Over Ground: Direction in which the boat is moving over the ground.  
CTS Course To Steer: Optimum course to steer to return to the plotted course.  
DTG Distance To Go: Distance from the boat to the destination.  
ETA Expected Time of Arrival: At the destination, assuming that SOG and COG remain constant.  
DST Distance from boat to cursor (cursor mode, see section 3-2)  
SOG Speed Over Ground: Current boat speed over the ground. This is not necessarily the same as the boat  
speed through the water nor the speed at which it is approaching the destination.  
STR  
TTG  
XTE  
Steering: The difference between COG and CTS.  
Time To Go: The estimated time to reach the destination.  
Cross Track Error: The distance from the boat to the nearest point of the plotted course. XTE may have  
a letter: R means steer to the right to return to the plotted course, L means steer to the left.  
VMG Velocity Made Good: The speed at which the boat is approaching the destination.  
Destination  
Destination  
Plotted  
course  
DTG (distance)  
VMG (speed)  
XTE  
(distance)  
SOG (speed)  
STR  
Boat  
position  
BRG  
COG  
CTS  
CDI scale  
(distance)  
CDI scale  
(distance)  
Plotted  
course  
Boat position  
Start  
Start  
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Appendix D Compliance statements  
FCC Statement  
Note: This equipment has been tested and found to comply with the limits for a Class B digital  
device, pursuant to Part 15 of the FCC Rules. These limits are designed to provide reasonable  
protection against harmful interference in a normal installation. This equipment generates, uses  
and can radiate radio frequency energy and, if not installed and used in accordance with the  
instructions, may cause harmful interference to radio communications. However, there is no  
guarantee that interference will not occur in a particular installation. If this equipment does cause  
harmful interference to radio or television reception, which can be determined by turning the  
equipment off and on, the user is encouraged to try to correct the interference by one or more  
of the following measures:  
Reorient or relocate the receiving antenna.  
Increase the separation between the equipment and receiver.  
Connect the equipment into an output on a circuit different from that to which the  
receiver is connected.  
Consult the dealer or an experienced technician for help.  
A shielded cable must be used when connecting a peripheral to the serial ports.  
Industry Canada  
Operation is subject to the following two conditions (1) this device may not cause interfer-  
ence, and (2) this device must accept any interference, including interference that may cause  
undesired operation of the device.  
Hereby, Northstar New Zealand, declares that this M121/M84 is in compliance with the essential  
requirements and other relevant provisions of Directive 1999/5/EC.  
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AMERICAS  
30 Sudbury Road,  
EUROPE  
Unit 2, Ocean Quay,  
Belvidere Rd, Southampton,  
SO14 5QY, ENGLAND  
Ph: +44 2380 339922  
Fax: +44 2380 330345  
northstaruk@northstarnav.com  
Acton, MA 01720, USA  
Ph: +1 978.897.6600  
Ph: +1 800.628.4487  
Fax: +1 978.897.7241  
sales@bntmarine.com  
AUSTRALIA  
PO Box 479,  
NEW ZEALAND  
PO Box 68 155,  
Gladesville, NSW 2111,  
AUSTRALIA  
Newton, Auckland  
Auckland, NEW ZEALAND  
Ph: +64 9 481 0500  
Fax: +64 9 481 0590  
northstarnz@northstarnav.com  
Ph: +61 2 9879 9060  
Fax: +61 2 9879 9009  
northstaraus@northstarnav.com  
www.northstarnav.com  
Made in New Zealand  
MN000638A-G  
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