User manual NORTHSTAR 491 ECHOSOUNDER

[. . . ] Northstar 491 Echo Sounder Operations Manual This manual is for using the 491 sounder with the Northstar 957, 958, 961 and 962 navigators. For the Northstar 6000i, information in Section 6 of its manual can be used instead. Revision A Part Number GM494 Northstar 30 Sudbury Road Acton, Massachusetts 01720 a unit of Brunswick New Technologies Marine Electronics www. NorthstarNav. com Service: 978/897-6600 Sales: 800/628-4487 Contents 1 Welcome . 1 Welcome to the Northstar 491 Using this manual . . . . . 2 2 4 5 7 7 Quick Start: Using the Echo Sounder . [. . . ] You can choose any one of nine palettes of colors to represent the echo strengths from weakest to strongest. · · · · Color bar #1 is the one most often used. Color bar #2 is similar but with fewer colors, to aid visibility under some conditions. Color bars # 3-8 are additional variations with different background colors. Color bar #9 uses only a single color, ranging from very dark to very bright. Selecting the color bar (hue) To select the color bar: 1. At the HUE AND WHITE LEVEL window, press the CURSOR PAD left or right to select the color bar desired, or use the KEYPAD to manually enter the number of the color bar. Page 32 491 Echo Sounder Operations Manual Hue and white level window 4. Press RETURN to go back to the ECHO screen. Setting the white level You can replace any single color in the color bar with white. On the HUE AND WHITE LEVEL window, press the CURSOR PAD up or down to select that color. To remove the white level and return to using all the colors on the color bar, press the CURSOR PAD down until the white level moves off the color bar. 491 Echo Sounder Operations Manual Page 33 Page 34 491 Echo Sounder Operations Manual 4Unde rstanding Depth Settings Viewing the seabed depth . 4-36 Setting the picture's shift (starting depth) . 4-38 Thisdepth settings andhow to override thethe depth autochapter explains system's matic manually control range shown on the screen, and how to use the depth marker. 491 Echo Sounder Operations Manual Page 35 Viewing the seabed depth The seabed depth (the "bottom") is displayed in a black box at the left edge of the ECHO screen. You can change the size and location of the depth box on the ECHO screen. Its size on the SOUNDTRAC screen is always small. There are four available sizes: · · · · small medium large huge To resize the depth box or move it up or down: 1. To cycle through the size choices, repeatedly press BOTTOM BOX. To move the box up and down, press the CURSOR PAD. Press RETURN to go back to the ECHO screen. The depth box can also be adjusted by pressing MORE, then pressing DATA. Viewing the depth marker You can use the depth marker to accurately measure the depth of an echo. To display the depth marker--a dashed horizontal line--and move this marker up or down, press the CURSOR PAD down. Attached to the depth marker line is a small black box, which displays the marker's exact depth. The depth marker also affects the display in Marker Zoom mode. Changing the depth settings You can adjust the shallowest and deepest echoes to be shown on the ECHO screen. In automatic mode, the echo sounder sets these values based on its current environment. [. . . ] Check the transducer periodically. Page 66 491 Echo Sounder Operations Manual A 491 Features and Specifications Table 4: 491 echo sounder features Performance characteristics Output Alarms Update rate Auto modes Zoom modes Features Single/Dual Channel, 50/200kHz, 600W Fish, seabed, temperature 10 Hz maximum (depends on water depth) Fishing and cruising Marker, bottom, bottom lock, bottom lock/center Mark present or past echo as waypoint (961/962) Go directly to any past echo A-scope analyzes present or past echoes Navigation data shown at bottom of screen Demo mode for training 491 Echo Sounder Operations Manual Page 67 Table 4: 491 echo sounder features (Continued) Screen notations Echo data Seabed depth (various size digits) Frequency of each window Speed through water (if connected) Water temperature (if connected) Depth scale for each window Depth of depth marker Latitude/longitude of position marker and vessel Alarm status and auto/manual status Zoom mode Name of waypoint, and distance and bearing to waypoint Steering indicator Interfacing Connects Northstar 961/962 GPS Chart Navigator Northstar 957/958/6000i GPS Chart Navigator Northstar-recommended or compatible transducer Transducer outputs protected against open circuit/ short circuit LED monitors input power and system status Other Physical characteristics Dimensions Weight 8. 78 x 7. 22 x 2. 35 inches 2 pounds Environmental characteristics Temperature Protection Standards -25ºC to +60ºC operating temperature -55ºC to +90ºC storage temperature 8 to 36 VDC, 8 Watts, reverse polarity and overvoltage protection Waterproof design meets the following: IEC60529 IP6; IEC60945 emissions; CE mark Page 68 491 Echo Sounder Operations Manual Table 4: 491 echo sounder features (Continued) Manual controls Gain Clutter Signal level Noise limiter White level Other 0 to 75 db 0 to 9 0 to 5 ON/OFF Any single color Screen color palette Depth marker Position marker Zoom in/out Shift 15, 30, 60, 120, 200, 400, 800, 1000, 2400 feet 5, 10, 20, 40, 80, 150, 300, 500, 800 meters 1/8 to 2/1 Feet, meters, fathoms Include speed, temperature, gain, and transducer type Ranges Advance speed Depth units Installation calibrations 491 Echo Sounder Operations Manual Page 69 Page 70 491 Echo Sounder Operations Manual G Glossary A-scope COG A horizontally magnified view of each echo, where the strength is shown by the width as well as the color of the line. The actual path of your vessel relative to the surface of the earth. Distracting echoes caused by turbulence, plankton, etc. The horizontal movement of water caused by tidal or other forces. [. . . ]