Summary of Contents for Hummingbird Communications 300 Series
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345c and 345c DI 345c and 345c DI Operations Manual Operations Manual 531955-1EN_A...
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Thank You! Thank you for choosing Humminbird®, America’s #1 name in fishfinders. Humminbird® has built its reputation by designing and manufacturing top-quality, thoroughly reliable marine equipment. Your Humminbird® is designed for trouble-free use in even the harshest marine environment. In the unlikely event that your Humminbird®...
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To obtain a list of authorized international distributors, please visit our Web site at humminbird.com or contact our Customer Resource Center at (334) 687-6613. 300 Series™, Down Imaging™, DualBeam PLUS™, Fish ID+™, Humminbird®, RTS™, RTS Window™, Structure ID®, SwitchFire™, WhiteLine™, and X-Press™ Menu are trademarked by or registered trademarks of Humminbird®.
Table of Contents Power On How Sonar Works DualBeam PLUS™ Sonar ........ 4 (DualBeam PLUS™ models only [345c]) Down Imaging™ Sonar ........ 5 (Down Imaging™ models only [345c DI]) Dual Beam Ice Transducer ....6 (optional-purchase XI 9 20 Ice Transducer only) What’s on the Sonar Display Understanding the Sonar Display ................
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Table of Contents What’s on the 300 Series™ Control Head Key Functions POWER/LIGHT Key ....................31 VIEW Key ......................31 MENU Key ......................32 4-WAY Cursor Control Key .................. 32 EXIT Key ........................ 33 The Menu System Start-Up Options Menu Normal........................
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Table of Contents Zoom Level ................46 (Sonar Zoom View only) Bottom Lock ................ 46 (Sonar Zoom View only) Bottom Range ........47 (Sonar Zoom View only when Bottom Lock is On) Down Imaging™ X-Press™ Menu (Down Imaging™ Views only [345c DI]) Imaging Sensitivity ....................
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Table of Contents Surface Clutter ...................... 61 SwitchFire™ ......................61 Fish ID+™ ......................62 Fish ID Sensitivity ....................63 Real Time Sonar (RTS™) Window ................ 63 Sonar Colors ......64 (Sonar View, Sonar Zoom View, and Big Digits View) Bottom View ......................64 Zoom Width ......................
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Demonstration......................74 Sound Control ......................74 Troubleshooting Fishfinder Doesn’t Power Up .................. 75 Fishfinder Defaults to Simulator with a Transducer Attached ......75 Display Problems...................... 76 Finding the Cause of Noise ..................77 300 Series™ Fishfinder Accessories Specifications Glossary Contact Humminbird®...
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Table of Contents NOTE: Entries in this Table of Contents which list (International Only) are only available on products sold outside of the U.S. by our authorized international distributors. To obtain a list of authorized international distributors, please visit our Web site at humminbird.com or contact our Customer Resource Center at (334) 687-6613.
Power On Follow the instructions below to power on your Humminbird® control head. 345c Title Screen 1. Press the POWER/LIGHT key. 2. When the Title screen is displayed, press the MENU key to access the Start-Up Options Menu. 3. Use the 4-WAY Cursor Control key to select Normal (if there is a transducer attached to the control head), or Simulator (if there isn’t a transducer attached to the control head).
How Sonar Works Sonar technology is based on sound waves. The 300 Series™ Fishfinder uses sonar to locate and define structure, bottom contour and composition, as well as depth directly below the transducer. Your 300 Series™ Fishfinder sends a sound wave signal and determines distance by measuring the time between the transmission of the sound wave and when the sound wave is reflected off of an object;...
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When all the echoes are viewed side by side, an easy to interpret “graph“ of the bottom, fish, and structure appears. The sound pulses are transmitted at various frequencies depending on the application. Very high frequencies (455 kHz) are used for greatest definition but the operating depth is limited.
DualBeam PLUS™ Sonar (DualBeam PLUS™ models only [345c]) Your 345c Fishfinder uses a 200/83 kHz DualBeam PLUS™ sonar system with a wide (60°) area of coverage. DualBeam PLUS™ sonar has a narrowly focused 20° center beam, surrounded by a second beam of 60°, expanding your coverage to an area equal to your depth.
Down Imaging™ Sonar (Down Imaging™ models only [345c DI]) Your 345c DI Fishfinder uses Down Imaging™ technology. The Down Imaging™ transducer scans the water with razor-thin, 45° 800kHz high-definition beams. The beams are wide 75° 455kHz (side to side) but very thin front to back. 16°...
Dual Beam Ice Transducer Ice transducer (optional-purchase XI 9 20 Ice Transducer only) Your Fishfinder supports the optional- purchase XI 9 20 Ice Transducer which provides selectable dual-frequency sonar with a wide area of coverage. Selectable dual-frequency gives you the option of two beams, and both beams will cover the bottom and provide high definition.
What’s on the Sonar Display The 300 Series™ Fishfinder can display a variety of useful information about Depth - Water depth; can be set to alarm when the water becomes too shallow. Temperature - Water surface temperature. Timer - Elapsed time with Temp/Speed Accessory.
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Sonar View to provide depth of a sonar return and bottom depth below the cursor. RTS (Real Time Sonar) Window™ Structure - Where fish may be hiding. Low Sonar Intensity Return the 300 Series™ Fishfinder. What’s on the Sonar Display...
Understanding the Sonar Display It is important to understand the significance of the display. The display does not show a literal 3-dimensional representation of what is under the water. Each vertical band of data received by the control head and plotted on the display represents something that was detected by a sonar return at a particular time.
SwitchFire™ SwitchFire™ controls how the sonar returns are displayed in the Sonar Views. SwitchFire™ settings are available in the Sonar Menu Tab. To see the maximum sonar information available within the transducer beam so more fish arches and better jig tracking are shown, choose Max Mode. To see less clutter and more fish size accuracy interpreted from the transducer beam, choose Clear Mode.
Bottom Presentation As the boat moves, the unit charts the changes in depth on the display to create a profile of the Bottom Contour. The type of bottom can be determined from the return charted on the display. A Hard Bottom such as compacted sediment or flat rock appears as a thinner line across the display.
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Structure ID® represents weak returns in blue and strong returns in red. WhiteLine™ highlights the strongest sonar returns in white, resulting in a distinctive outline. This has the benefit of clearly defining the bottom on the display. What’s on the Sonar Display...
What’s on the Down Imaging™ Display Down Imaging™ uses its unique transducer and sonar technology to provide definition profiling beams produce the detailed sonar data that you see on the can interpret the structure and bottom contour, including the following items: Depth - (water depth) can be set to alarm when the water becomes too shallow.
The longer the shadow, the taller the object. Fish also cast shadows. You can use the shadow to interpret how close the fish is to the bottom. Lower Range connected to the 300 Series™ Fishfinder. What’s on the Down Imaging™ Display...
Understanding the Down Imaging™ Display The images you see on the Down Imaging™ display are produced using sonar technology. Each time the unit pings, a strip of data representing all the echoes received by the transducer are put together on the display to form the image that you see.
Down Imaging™ Sensitivity Use Imaging Sensitivity to control how the sonar returns appear on the display. Increase the sensitivity to reveal weaker returns that may be of interest, especially in very clear water or greater depths. Decrease the Imaging Sensitivity to eliminate the clutter from the display that is sometimes present in murky or muddy water.
Views The sonar information from your Fishfinder is displayed on your screen in a variety of easy-to-read views. There are many views available on your Fishfinder. • Default View: When you first power up the 345c control head, Sonar View will be the default view. When you first power up the 345c DI control head, Down Imaging™...
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To customize your view rotation: You can choose which views are hidden or visible in your view rotation. 1. Press the MENU key twice to access the tabbed Main Menu, then press the RIGHT Cursor key until the Setup tab is selected. 2.
Sonar View Sonar View presents a historical log of sonar returns. The most recent sonar returns are charted on the right side of the display. As new information is received, the historical information scrolls left across the display. • Upper and Lower Depth Range numbers indicate the distance from the surface of the water to a depth range sufficient to show the bottom.
Sonar Zoom View Sonar Zoom View provides a magnified view of the bottom and structure. The Sonar Zoom View makes it easier to see separate sonar returns that would usually be displayed close together, such as those caused by fish suspended close to the bottom or within structure.
Split Sonar View Split Sonar View displays sonar returns from each down beam frequency on separate sides of the screen. You can use the Split Sonar View to make side by side comparisons between the sonar returns from both beams. •...
Big Digits View Big Digits View provides digital data in a large, easy-to-see format. • Digital Readouts: Depth is always displayed. Readouts for temperature, speed, and Triplog information are displayed automatically if the appropriate accessory is connected to the Fishfinder. NOTE: The digital readouts in the Big Digits View cannot be customized.
Down Imaging™ View (Down Imaging™ models only [345c DI]) Down Imaging™ View uses the razor-thin, high-definition profiling beams to produce the detailed sonar data that you see on the display. Sonar returns are charted on the right side of the display. As new information is received, the historical information scrolls left across the display.
Circular Flasher View Circular Flasher View provides two ways to view sonar data in traditional flasher format. The view is controlled by the Ice Fishing Mode menu option in the Sonar Menu Tab. • When Ice Fishing Mode is off, the Circular Flasher View displays Real Time Sonar (RTS™) data in a traditional flasher format.
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Ice Fishing Mode: Off When Ice Fishing Mode is off, the Circular Flasher View displays Real Time Sonar (RTS™) data in a traditional flasher format. • Flasher X-Press™ Menu: Press the MENU key once in the Circular Flasher View. Use the X-Press™ Menu to set the Sensitivity, Upper Range, and Lower Range.
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Ice Fishing Mode: On When Ice Fishing Mode is on, the Circular Flasher View displays the sonar data in traditional flasher format with additional features including Zoom and Depth Cursor. • Sensitivity: When you turn on Ice Fishing Mode, the fishfinder’s sensitivity settings are adjusted automatically to accommodate ice fishing conditions.
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To activate the Depth Cursor: Use the Depth Cursor to identify depth on the flasher display. 1. Set up: Press the VIEW key repeatedly until the Circular Flasher View is displayed on the screen. Turn on the Ice Fishing Mode (see Sonar Menu Tab).
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To activate Flasher Zoom: The Zoom feature displays a 2x magnified view of the area you choose on the flasher display. 1. Set up: Press the VIEW key repeatedly until the Circular Flasher View is displayed on the screen. Turn on the Ice Fishing Mode (see Sonar Menu Tab).
Down Imaging™/Sonar Combo View (Down Imaging™ models only [345c DI]) Down Imaging™/Sonar Combo View shows traditional Sonar information on the top of the screen and Down Imaging™ sonar information on the bottom. • X-Press™ Menu: Press the MENU key once to access the Down Imaging™...
What’s on the 300 Series™ Control Head Your 300 Series™ Fishfinder interface is easy to use. A combination of keys and special features allows you to control what you see on the display. Refer to the following illustration, and see Key Functions for more information.
Light or Background, and then use the LEFT or RIGHT Cursor key to change the settings. Press EXIT to exit the Light and Background submenu. NOTE: Your 300 Series™ Fishfinder will start up with the backlight on and will automatically turn it off to conserve power. VIEW Key The VIEW key is used to cycle through all available views.
MENU Key The MENU key is used to access the menu system. See The Menu System for more information. • Start-Up Options Menu: Press the MENU key during the power up sequence to view the Start-Up Options menu. • X-Press™ Menu: Press the MENU key once in any view to access the X-Press™...
EXIT Key The EXIT key has multiple functions, which depend on the situation: • If an alarm is sounding, press the EXIT key to cancel the alarm. • If a menu tab is selected, press the EXIT key to exit the menu mode and return to the view.
The Menu System The Menu System is divided into easy-to-use menu modules as follows: • Start-Up Options Menu: Press the MENU key during the power on sequence to view the Start-Up Options Menu. From the Start-Up Options Menu, you can choose the following Fishfinder Modes: Normal, Simulator, and System Status.
Start-Up Options Menu Press the MENU key during the power on sequence to view the Start-Up Options Menu, and select one of the modes described on the following pages. Also, see Power On for additional information. Normal Use Normal for on-the-water operation with a transducer connected. If a functioning transducer is connected, Normal operation will be selected automatically at power up, and your Fishfinder can be used on the water.
Simulator Use Simulator to learn how to use your Fishfinder before taking your boat on the water. The Simulator is a very powerful tool that provides a randomly-updated display which simulates on the water operation. Simulator We recommend going through this manual while using the Simulator, since all of the menus function and affect the display in the same way as they would in Normal...
Self Test Screen Self Test displays results from the internal diagnostic self test, including unit serial number, Printed Circuit Board (PCB) serial number, software revision, total hours of operation, and the input voltage. Accessory Test Accessory Test lists the accessories connected to the system.
X-Press™ Menu The X-Press™ Menu provides a shortcut to your most frequently-used settings. The options provided on the X-Press™ Menu correspond with the current view. For example, if you are in a Sonar View and press the MENU key once, the Sonar X-Press™...
Main Menu The Main Menu provides the standard set of menu options, including the settings that are changed less frequently. The Main Menu is organized under the following tabs to help you find a specific menu item quickly: Alarms, Sonar, and Setup. NOTE: Menu options can be expanded or simplified by setting the User Mode to Advanced or Normal.
Quick Tips for the Main Menu • From any menu option on a menu tab, press the EXIT key to jump directly to the top of the tab. • From the bottom of a menu tab, press the DOWN Cursor key to jump directly to the top of the tab.
Menu options can be simplified or expanded by setting your Fishfinder User Mode to Normal or Advanced. Normal Mode is the default setting when you first power on your 300 Series™ Fishfinder. Normal mode is provided for users who want greater simplicity and fewer menu choices.
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Sonar Menu Tab, Normal Mode Sonar Menu Tab, Advanced Mode Main Menu...
Sonar X-Press™ Menu (Sonar Views only) The Sonar X-Press™ Menu provides a shortcut to your most frequently-used settings. Press the MENU key once while in any of the Sonar Views to access the Sonar X-Press™ Menu. NOTE: Menu options can be expanded or simplified by setting the Fishfinder User Mode to Advanced or Normal.
Sensitivity Settings: Low = 1, High = 20; Default = 10 Sensitivity controls how much detail is shown on the display and will adjust the sensitivity of all sonar frequencies. When operating in very clear water or greater depths, increase the sensitivity to see weaker returns that may be of interest.
Upper Range (Advanced: Sonar, Split Sonar, Circular Flasher, and Big Digits Views only) Settings: 0 to 990 feet or 0 to 327 meters [International Models only]; Default = 0 feet Upper Range sets the shallowest depth range that will be displayed on the Sonar, Split Sonar, Circular Flasher, and Big Digits Views.
Chart Speed Settings: 1-9, Ultra, where 1 = Slow, 9 = Fast, Ultra = Fastest; Default = 5 Chart Speed determines the speed at which the sonar information moves across the display, and consequently the amount of detail shown. A faster speed shows more information and is preferred by most anglers; however, the sonar information moves across the display quickly.
Bottom Range (Sonar Zoom View only when Bottom Lock is On) Settings: 10 - 60 feet, 2-10 fathoms, or 3-20 meters [International Models only], Default = 15 feet Bottom Range allows you to control how much of the water column, measured up from the bottom, is shown in the Sonar Zoom View.
Down Imaging™ X-Press™ Menu (Down Imaging™ Views only [345c DI]) The Down Imaging™ X-Press™ Menu provides a shortcut to your most frequently- used settings. Press the MENU key once while in any of the Down Imaging™ Views to access the Down Imaging™ X-Press™ Menu. NOTE: Menu options can be expanded or simplified Down Imaging™...
Imaging Sensitivity Settings: Auto, 1 to 20, where Low = 1, High = 20; Default = 10 Imaging Sensitivity controls how the sonar returns are displayed on the Down Imaging™ Views. Increase the Imaging Sensitivity to reveal weaker returns that may be of interest, especially in very clear water or greater depths.
Lower Range Settings: Auto, 10 to 1000 feet, 3 to 330 meters [International Models only]; Default = Auto Lower Range sets the deepest depth range that will be displayed by the unit. Auto: The Lower Range will be adjusted by the unit to follow the bottom automatically.
Flasher X-Press™ Menu (Circular Flasher View only) The Flasher X-Press™ Menu provides a shortcut to your most frequently-used settings. Press the MENU key once while in the Circular Flasher View to access the Flasher X-Press™ Menu. NOTE: Menu options can be expanded or simplified by setting the User Mode to Advanced or Normal.
Sensitivity Settings: Low = 1, High = 20; Default = 10 Sensitivity controls how much detail is shown on the display and will adjust the sensitivity of all sonar frequencies. When operating in very clear water or greater depths, increase the sensitivity to see weaker returns that may be of interest.
Lower Range Settings: Auto, 10 to 1000 feet, 3 to 330 meters [International Models only]; Default = Auto Lower Range sets the deepest depth range that will be displayed by the unit. Auto: The Lower Range will be adjusted by the unit to follow the bottom automatically.
Zoom Level (Circular Flasher View, Ice Fishing Mode only) Settings: 1x, 2x; Default = 1x Zoom Level sets the magnification level for the Circular Flasher View when Ice Fishing Mode is turned on. When the Zoom Level is set to 1x, the Zoom feature is turned off.
Alarms Menu Tab From any view, press the MENU key twice to access the Main Menu. The Alarms tab will be the default selection. NOTE: When an alarm is triggered, you can silence it by pressing any key. The alarm will be silenced, and will not be triggered again until a new instance of the alarm condition is detected.
Depth Alarm Settings: Off, 1 to 100 feet, or 0.5 to 30 meters [International Models only]; Default = Off Depth Alarm sounds when the depth becomes equal to or less than the menu setting. Fish ID Alarm Settings: Off, All, Large/Medium, Large; Default = Off Fish ID Alarm sounds when the Fishfinder detects fish that correspond to the alarm setting.
Temp. Alarm Settings: Off, 33-120 Fahrenheit, 0-50 Celsius [International Models only]; Default = Off Temp. Alarm sounds when the water temperature detected by the Fishfinder reaches the Temp. Alarm setting, which is either set in degrees Fahrenheit or Celsius [International Models only]. For example, if the Temp.
Sonar Menu Tab Press the MENU key twice to access the Main Menu and then press the RIGHT Cursor key until the Sonar tab is selected. NOTE: Menu options can be expanded or simplified by setting the User Mode to Advanced or Normal. See Main Menu: User Mode for details.
Beam Select Settings: DualBeam PLUS™: 200/83 kHz, 200 kHz, 83 kHz; Down Imaging™: 200 kHz, 455 kHz; Default = 200 kHz Beam Select sets which sonar returns from the transducer will be displayed on the screen. The available beam frequencies are determined by your Humminbird®...
The Down Imaging™ models (345c DI) allow you to choose 200 kHz or 455 kHz for conical sonar coverage in the traditional sonar views. • When set to 200 kHz, only the returns from the 200 kHz (25°) beam will be 45°...
Surface Clutter Settings: Low = 1 to High = 10; Default = 5 Surface Clutter adjusts the filter that removes surface clutter noise caused by algae and aeration. The lower the setting, the less surface clutter will be displayed. Surface Clutter Surface Clutter SwitchFire™...
Fish ID+™ Settings: Off, On; Default = Off Fish ID+™ uses advanced signal processing to interpret sonar returns and will display a Fish Symbol when very selective requirements are met. When a fish is detected, a fish icon and its depth are displayed above the return that has been classified as being a fish.
Fish ID Sensitivity Settings: Low = 1, High = 10; Default = 5 Fish ID Sensitivity adjusts the threshold of the Fish ID+™ detection algorithms. Selecting a higher setting allows weaker returns to be displayed as fish. This is useful for identifying smaller fish species or baitfish. Selecting a lower setting displays fewer fish from weak sonar returns.
Sonar Colors (Sonar View, Sonar Zoom View, Circular Flasher View, and Big Digits View) Settings: Gray, Green, Inverse, Original Palette, Palette 1, Palette 2, Palette 3; Default = Original Palette Sonar Colors allows you to select which color palette you would like to use for the display.
Zoom Width Settings: Narrow, Medium, Wide; Default = Wide Zoom Width adjusts the width of the zoomed view on the Sonar Zoom View, which is on the left side of the display. See Views: Sonar Zoom View for more information. 83 kHz Sensitivity (Advanced, DualBeam PLUS™...
Depth Lines (Advanced) Settings: Off, On; Default = On Depth Lines divide the display into four equal sections which are separated by three horizontal depth lines. The depth of each line is displayed along the depth scale. You can turn Depth Lines On or Off. Depth Lines Depth Lines Noise Filter...
Max Depth (Advanced) Settings: Auto, 10 to 1000 feet, 3 to 330 meters [International Models only]; Default = Auto Max Depth controls the maximum depth of operation. When Max Depth is set to Auto, the Fishfinder will acquire bottom readings as needed (within the capacity of the unit).
Imaging Colors (Down Imaging™ Views only [345c DI]) Settings: Blue, Amber 1, Amber 2, Brown, Green, Inverse, Gray, Green/Red; Default = Blue Imaging Colors allows you to select which color palette you would like to use for the Down Imaging™ display. Sonar Menu Tab...
Setup Menu Tab From any view, press the MENU key twice to access the tabbed Main Menu, then press the RIGHT Cursor key until the Setup tab is selected. NOTE: Menu options will vary depending on which accessories are attached to the unit. NOTE: Menu options can be expanded or simplified by setting the User Mode to Advanced or Normal.
Units - Depth Settings: Domestic Models: Feet, Fathoms; International Models: Meters; Default = Feet/Meters Units - Depth selects the units of measure for all depth-related readouts. Units - Temp (International only) Settings: Celsius, Fahrenheit; Default = Celsius Units - Temp selects the units of measure for all temperature-related readouts. International Models only.
User Mode Settings: Normal, Advanced; Default = Normal User Mode sets the menu system to Normal or Advanced. When set to Normal (default setting), the basic set of menu options are shown in the menu system. When set to Advanced, additional menu options are added to the menu system. See Main Menu: User Mode for details.
Select Views (Advanced) Settings: Visible, Hidden, Default = Visible Select Views allows you to set the available views to hidden or visible in the view rotation. The view will be removed from the view rotation if it is set to Hidden and will be displayed in the view rotation if it is set to Visible.
Default Sonar View Sonar View with Select Readouts Depth Offset (Advanced) Settings: -10.0 to +10.0 feet, or -3.0 to 3.0 meters [International Models only]; Default = 0 feet Depth Offset will adjust the digital depth readout to indicate depth from the waterline or boat's keel.
Digits Format (Advanced) Settings: Small tenths, Large tenths, No tenths, Default = Small tenths Digits Format adds a tenth decimal place to the readouts such as Temperature and Depth. Use the settings to change the display of the decimal place or remove it from the digital readouts.
Troubleshooting Before contacting the Humminbird® Customer Resource Center, please read the following section. Taking the time to review these troubleshooting guidelines may allow you to solve a performance problem yourself, and therefore avoid sending your unit back for repair. Fishfinder Doesn’t Power Up If your Fishfinder doesn’t power up, use the Installation Guide that also comes with it for specific confirmation details, making sure that: •...
Display Problems There are several main conditions or sources of possible interference that may cause problems with the quality of the information displayed on the control head. Look in the following table for some symptoms of display problems and possible solutions: Problem Possible Cause The control head loses...
Finding the Cause of Noise Electrical noise usually affects the display with many black dots at high speeds, and high sensitivity readings. One or more of the following sources can cause noise or interference: Possible Source of Noise Isolation Turn off any nearby electronic devices to see Other electronic devices if the problem goes away, then turn them on one at a time to see if the noise re-appears.
300 Series™ Fishfinder Accessories Accessories customize the Humminbird® Fishfinder to your needs and enable you to stay on the edge of new technology. When an accessory is connected to the Humminbird® Fishfinder, additional menus and readouts are added automatically to the Main Menu System. Accessories available today that are supported by your Humminbird®...
Glossary Sonar Terms: Beam (Sonar Beam) The wide, cone-shaped projection of sound waves formed as sound Cone Angle travels underwater. See Bottom Contour The profile of the bottom graphed to the display as the depth changes. Bottom Hardness The density (or composition) of the bottom. Varying levels of hardness can be determined by interpreting the “thickness“...
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Grayscale The use of varying shades of gray to represent the strength of the sonar signal on the display. Traditionally, the strongest sonar signals are represented in black, and progressively weaker signals are represented in progressively lighter shades of gray. Noise The unintentional, external sound waves that interfere with the optimal operation of sonar.
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SONAR (SOund and NAvigation Ranging) Sonar technology uses precision sound bursts transmitted underwater to determine the distance and other attributes of objects in the water. Distance can be determined because the speed of sound in water is constant, and the time for the signal to return is measured. Sound also travels very quickly underwater, making sonar a responsive, cost-effective tool.
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Thermoclines Water layer(s) of distinctly different temperatures that create a sonar reflection due to the density of the differing water temperatures. Typically a thermocline will appear as a continuous band across the display at some distance above the bottom contour. Thermoclines are of interest to anglers because fish will suspend above or below the thermocline as they seek the optimum temperature and oxygen levels.
Contact Humminbird® Contact the Humminbird® Customer Resource Center in any of the following ways: By Telephone: (Monday - Friday 8:00 a.m. to 4:30 p.m. Central Standard Time): 1-800-633-1468 By e-mail: (typically we respond to your e-mail within three business days): service@humminbird.com For direct shipping, our address is: Humminbird...
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