Humminbird 931C User manual

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i
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® does require repairs, we offer an exclusive Service Policy - free of charge
during the first year after purchase, and available at a reasonable rate after the one-
year period. For complete details, see the Warranty section in this manual. We
encourage you to read this installation and operations manual carefully in order to get
full benefit from all the features and applications of your Humminbird® product.
Contact our Customer Resource Center at either 1-800-633-1468 or visit our website at
www.humminbird.com.
WARNING! This device should not be used as a navigational aid to prevent collision,
grounding, boat damage, or personal injury. When the boat is moving, water depth may
change too quickly to allow time for you to react. Always operate the boat at very slow
speeds if you suspect shallow water or submerged objects.
WARNING! Disassembly and repair of this electronic unit should only be performed by
authorized service personnel. Any modification of the serial number or attempt to repair the
original equipment or accessories by unauthorized individuals will void the warranty.
Handling and/or opening this unit may result in exposure to lead, in the form of solder.
WARNING! This product contains lead, a chemical known to the state of California to cause
cancer, birth defects and other reproductive harm.
DualBeam PLUS™, Fish ID+™, Humminbird®, HumminbirdPC™, RTS® Window, SmartCast®, WhiteLine®,
X-Press™ Menu, Structure ID®, and WeatherSense® are trademarked by or registered trademarks of
Humminbird®.
© 2005 Humminbird®, Eufaula AL, USA. All rights reserved.
531370-1_A
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TABLE OF CONTENTS
900 Series™ Introduction 1
How the 900 Series™ Works .................................................................................................................... 1
Single Beam Sonar ........................................................................................................................................ 1
DualBeam PLUS™ Sonar ............................................................................................................................ 1
GPS and Cartography (937c DF Combo and 937c Combo models only)............................................ 2
Multi-Media Card (MMC)/SD Slot............................................................................................................ 2
Accessory Bus.................................................................................................................................................. 3
Installation Overview 3
Control Head Installation 4
Gimbal Mounting the Control Head ...................................................................................................... 4
In-Dash Mounting the Control Head ...................................................................................................... 8
Connecting the Control Head Power Cable to the Boat ................................................................ 10
Transducer Installation 10
Transom Transducer Installation ............................................................................................................ 11
Inside the Hull Transducer Installation ................................................................................................ 17
Trolling Motor Transducer Installation ................................................................................................ 19
Test and Finish the Transducer Installation ...................................................................................... 19
GPS Receiver Installation (937c DF Combo and 937c Combo models only) 20
Stem Mounting with an Existing 1" - 14 Thread Stem.................................................................... 20
Access Under Mounting Location.......................................................................................................... 21
No Access Under Mounting Location .................................................................................................. 22
Finish Routing the Cable and Check GPS Receiver Operation...................................................... 22
Speed Accessory Installation 23
Testing the System Installation 25
Getting Started - Using Your 900 Series™ 26
Powering Up the Control Head ............................................................................................................ 26
What’s on the Sonar Display .................................................................................................................. 27
Understanding Sonar History ................................................................................................................ 28
Real Time Sonar (RTS®) Window .......................................................................................................... 28
Bottom Presentation.................................................................................................................................. 28
Key Functions 29
POWER/LIGHT Key .................................................................................................................................... 29
VIEW Key........................................................................................................................................................ 30
MENU Key .................................................................................................................................................... 30
4-WAY Cursor Control Key ........................................................................................................................ 30
View Preset Keys.......................................................................................................................................... 31
EXIT Key .......................................................................................................................................................... 31
INFO Key (937c DF Combo and 937c Combo models only) .................................................................. 31
MARK/GOTO Key (937c DF Combo and 937c Combo models only) .................................................. 31
ZOOM (+/- Key) (937c DF Combo and 937c Combo models only)...................................................... 31
Views 32
Views and Readouts .................................................................................................................................. 32
Sonar View .................................................................................................................................................... 33
Sonar Zoom View........................................................................................................................................ 33
Split Sonar View (937c DF Combo and 931c DF models only)............................................................ 34
Bird’s Eye View (937c DF Combo and 937c Combo models only) ...................................................... 35
Chart/Bird’s Eye Combo View (937c DF Combo and 937c Combo models only).......................... 36
Chart View (937c DF Combo and 937c Combo models only).............................................................. 36
Chart/Sonar Combo View (937c DF Combo and 937c Combo models only) ................................ 37
Chart Orientation ...................................................................................................................................... 38
Viewing Cartography (937c DF Combo and 937c Combo models only) 38
Navigation (937c DF Combo and 937c Combo models only) 39
Waypoints, Routes and Tracks................................................................................................................ 40
Save, Edit, or Delete a Waypoint .......................................................................................................... 40
Navigate to a Waypoint or Position ...................................................................................................... 41
Add a Waypoint Target or Trolling Grid .............................................................................................. 42
Save, Edit or Delete a Route .................................................................................................................... 43
Save or Clear a Current Track .................................................................................................................. 43
Edit, Delete or Hide Saved Tracks .......................................................................................................... 43
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TABLE OF CONTENTS
The Menu System 44
Start-Up Options Menu 45
Normal Operation ...................................................................................................................................... 46
Simulator ...................................................................................................................................................... 46
System Status .............................................................................................................................................. 47
Self Test .......................................................................................................................................................... 47
Accessory Test .............................................................................................................................................. 47
GPS Diagnostic View (937c DF Combo and 937c Combo models only) .......................................... 47
Sonar X-Press™ Menu 48
Active Side .................................................................................................................................................... 49
Split Position ................................................................................................................................................ 49
Sensitivity .................................................................................................................................................... 49
Upper Range (Advanced: Sonar, Split Sonar and Active Sonar Side Views only)............................ 50
Lower Range ................................................................................................................................................ 50
Chart Speed .................................................................................................................................................. 51
Zoom Level (Sonar Zoom View only) ........................................................................................................ 51
Bottom Lock (Sonar Zoom View only) .................................................................................................... 51
Sonar Colors .................................................................................................................................................. 51
Navigation X-Press™ Menu (937c DF Combo and 937c Combo models only) 52
Active Side .................................................................................................................................................... 52
Split Position ................................................................................................................................................ 52
Save Current Track ...................................................................................................................................... 53
Clear Current Track...................................................................................................................................... 53
Save Current Route (Only when navigating) ........................................................................................ 53
Skip Next Waypoint (Only when navigating) ...................................................................................... 53
Cancel Navigation (Only when navigating) .......................................................................................... 54
Remove Target (Only if a Target is active).............................................................................................. 54
Remove Grid (Only if a Grid is active)...................................................................................................... 54
Sonar Menu Tab 55
Beam Select (937c DF Combo and 931c DF models only) .................................................................... 55
Fish ID+™........................................................................................................................................................ 56
Fish ID Sensitivity........................................................................................................................................ 56
Real Time Sonar (RTS®) Window............................................................................................................ 57
Bottom View ................................................................................................................................................ 57
Zoom Width (Sonar Zoom View only) .................................................................................................... 57
50 kHz Sensitivity (Advanced, 937c DFCombo and 931c DF models only)...................................... 58
Depth Lines (Advanced).............................................................................................................................. 58
Surface Clutter (Advanced)........................................................................................................................ 58
Noise Filter (Advanced) .............................................................................................................................. 58
Max Depth (Advanced) .............................................................................................................................. 59
Water Type (Advanced) .............................................................................................................................. 59
Transducer Select........................................................................................................................................ 59
Color Bar ........................................................................................................................................................ 60
Temperature (Sonar View only, with Temperature input) ................................................................ 60
Navigation Menu Tab (937c DF Combo and 937c Combo models only) 60
Tracks .............................................................................................................................................................. 61
Waypoints...................................................................................................................................................... 61
Routes.............................................................................................................................................................. 61
Chart Orientation........................................................................................................................................ 62
North Reference .......................................................................................................................................... 62
Trolling Grid Rotation ................................................................................................................................ 62
Trackpoint Interval...................................................................................................................................... 62
Track Min Distance (Advanced)................................................................................................................ 62
Map Datum (Advanced) ............................................................................................................................ 63
Export All Nav Data (Advanced) .............................................................................................................. 63
Delete All Nav Data (Advanced) .............................................................................................................. 63
Chart Menu Tab (937c DF Combo and 937c Combo models only) 64
Chart Detail Level........................................................................................................................................ 64
Map Borders ................................................................................................................................................ 64
Lat/Lon Grid.................................................................................................................................................. 65
Spot Soundings............................................................................................................................................ 65
Shaded Depth .............................................................................................................................................. 65
Set Simulation Position (Advanced) ...................................................................................................... 65
Set Map Offset (Advanced) ...................................................................................................................... 66
Clear Map Offset (Advanced) .................................................................................................................. 66
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TABLE OF CONTENTS
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Alarms Menu Tab 66
Depth Alarm ................................................................................................................................................ 67
Fish ID Alarm ................................................................................................................................................ 67
Low Battery Alarm ...................................................................................................................................... 67
Temp Alarm .................................................................................................................................................. 67
Off Course Alarm (937c DF Combo and 937c Combo models only).................................................. 68
Arrival Alarm (937c DF Combo and 937c Combo models only).......................................................... 68
Drift Alarm (937c DF Combo and 937c Combo models only).............................................................. 68
Alarm Tone.................................................................................................................................................... 69
Setup Menu Tab 70
Units - Depth ................................................................................................................................................ 70
Units - Temp (International only) ............................................................................................................ 70
Units - Distance (With Speed input only) ................................................................................................ 71
Units - Speed (With Speed input only) .................................................................................................... 71
User Mode...................................................................................................................................................... 71
Language (International only).................................................................................................................... 71
Triplog Reset (With Speed input only) .................................................................................................... 72
Restore Defaults .......................................................................................................................................... 72
Select Readouts (Advanced)...................................................................................................................... 72
Depth Offset (Advanced)............................................................................................................................ 74
Temp Offset (Advanced) ............................................................................................................................ 74
Speed Calibration (Advanced, with Speed paddlewheel only) .......................................................... 74
Local Time Zone (Advanced, 937c DF Combo and 937c Combo models only) ................................ 74
Daylight Saving Time (Advanced, 937c DF Combo and 937c Combo models only) ...................... 75
Position Format (Advanced, 937c DF Combo and 937c Combo models only) ................................ 75
Time Format (Advanced, 937c DF Combo and 937c Combo Models, International only) ............ 75
Date Format (Advanced, 937c DF Combo and 937c Combo Models, International only).............. 75
NMEA Output (Advanced) ........................................................................................................................ 76
Sonar (937c DF Combo and 937c Combo models only) ........................................................................ 76
Views Menu Tab 77
Accessories Menu Tab 77
Troubleshooting 78
900 Series™ Doesn’t Power Up.............................................................................................................. 78
900 Series™ Defaults to Simulator with a Transducer Attached................................................ 78
Display Problems ........................................................................................................................................ 79
Finding the Cause of Noise...................................................................................................................... 80
1-Year Limited Warranty 81
Humminbird® Service Policy 81
900 Series™ Accessories 82
Specifications 83
Appendix A - Transducer Mounting Template (Single Frequency: XHS-9-20-T) 84
Appendix B - Transducer Mounting Template (Dual Frequency: XHS-9-DB-74-T) 85
Contact Humminbird® 86
NOTE: Entries in this Table of Contents which list (International Only) are only available on
products sold outside of the US and Canada by our authorized International Distributors.
To obtain a list of authorized International Distributors, please visit our website at
www.humminbird.com or contact our Customer Resource Center at 1-800-633-1468 to
locate the distributor nearest you.
NOTE: Entries in this Table of Contents which list (with Speed Input) or (with Temperature
Input) may require the purchase of separate accessories. You can visit our website at
www.humminbird.com to order these accessories online or contact our Customer Resource
Center at 1-800-633-1468.
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1
900 SERIES™ INTRODUCTION
Your 900 Series™ Ultra Wide Screen Fishing System comes in several different
configurations. See the following list of products, all of which are covered by this
manual, to find your 900 Series™ configuration:
NOTE: Only 937c DF Combo and 937c Combo models come with GPS and built-in
cartography.
• Humminbird® 931c: Ultra Wide Screen Fishing System with Single Frequency
200 kHz Transducer, optional GPS support
• Humminbird® 931c DF: Ultra Wide Screen Fishing System with Dual Frequency
200 kHz and 50 kHz Transducer, optional GPS support
• Humminbird® 937c Combo: Ultra Wide Screen Fishing System with Chartplotter
(Maps) and Single Frequency 200 kHz Transducer, GPS Receiver included
• Humminbird® 937c DF Combo: Ultra Wide Screen Fishing System with
Chartplotter (Maps) and Dual Frequency 200 kHz and 50 kHz Transducer, GPS
Receiver included.
HOW THE 900 SERIES™ WORKS
Sonar technology is based on sound waves. The 900 Series™ Fishing System uses
sonar to locate and define structure, bottom contour and composition, as well as
depth directly below the transducer. Your 900 Series™ Fishing System 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;
it then uses the reflected signal to interpret location, size, and composition of an
object. Sonar is very fast. A sound wave can travel from the surface to a depth of 240
ft (70 m) and back again in less than ¼ of a second. It is unlikely that your boat can
"outrun" this sonar signal.
SINGLE BEAM SONAR
Your 900 Series™ 937c Combo and 931c use a 200 kHz single
beam sonar system with a 20° area of coverage. Depth
capability is affected by such factors as boat speed, wave
action, bottom hardness, water conditions and transducer
installation.
NOTE: The 937c Combo and 931c models use single beam transducers, but may be upgraded
to dual beam functionality with the purchase and installation of a dual beam transducer.
Contact our Customer Resource Center at either 1-800-633-1468 or visit our website at
www.humminbird.com for more information.
NOTE: Your Single frequency (937c Combo or 931c model) 900 Series™ unit was shipped
from the factory with a Dual frequency software configuration. Before trying to operate
your unit, you will need to set your 900 Series™ to Single Beam in order for it to work
properly. See Sonar Menu Tab: Transducer Select for more information.
DUALBEAM PLUS™ SONAR
Your 900 Series™ 937c DF Combo and 931c DF are shipped
with a 200/50 kHz DualBeam PLUS™ sonar system with a
wide (74°) area of coverage. DualBeam PLUS™ sonar returns
can be blended together, viewed separately or compared
side-by-side. DualBeam PLUS™ is ideal for a wide range of
conditions -- from shallow to very deep water, in both fresh
and salt water. Depth capability is affected by such factors as
boat speed, wave action, bottom hardness, water conditions
and transducer installation.
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GPS AND CARTOGRAPHY (with 937c DF Combo and 937c Combo models only)
The 937c DF Combo and 937c Combo models use GPS and sonar to determine your
position, display it on a grid, and provide detailed underwater information. The Global
Positioning System (GPS) is a satellite navigation system designed and maintained by
the U.S. Department of Defense. GPS was originally intended for military use; however,
civilians may also take advantage of its highly accurate position capabilities, typically
within +/- 10 meters, depending on conditions. This means that 95% of the time, the
GPS receiver will read a location within 10 meters of your actual position. The GPS
Receiver also uses information from WAAS (the Wide Area Augmentation System),
EGNOS (the European Geostationary Navigation Overlay Service), and MSAS (the
MTSAT Satellite Augmentation System) satellites if they are available in your area.
GPS uses a constellation of satellites that continually send radio signals to the earth.
Your present position is determined by receiving signals from up to 12 satellites and
measuring the distance from the satellites. The GPS Receiver, when attached to your
937c DF Combo or 937c Combo model, allows you to combine easy-to-use FishingGPS™
chartplotter and navigation capabilities with advanced fishfinding. The following GPS
functionality is currently supported by the 937c DF Combo and 937c Combo models
when it is connected to a GPS Receiver:
• View current position
• View current track (breadcrumb trail)
• View precision speed and heading from your GPS receiver
• Save tracks, waypoints and routes
• Travel a route and navigate from one waypoint to the next.
NOTE: Only the 937c DF Combo and 937c Combo models support Navionics® Gold Charts
marine cartography and Navionics® HotMaps™ 2004 Gold for inland fishing. The 900
Series™ does not support Navionics® Classic Charts.
The 937c DF Combo and 937c Combo models also come with a built-in World map with a
more detailed map of North America (Domestic models) or a more detailed map of
Europe and Southeast Asia, including Australia and New Zealand (International models).
Your 937c DF Combo and 937c Combo models use the GPS Receiver to determine the
position of the boat automatically, and uses the zoom level settings on a particular
view to select the best chart to display. See Viewing Cartography for more information.
MULTI-MEDIA CARD (MMC)/SD SLOT
The 900 Series™ 937c DF Combo and 937c Combo models
support cartography, and have two multi-media card
(MMC)/SD slots. Optional-purchase MMC and/or SD cards
can contain additional detailed maps. You can also export
navigation data from your unit onto an MMC/SD card (see
Navigation Main Menu: Export All Nav Data). If you insert
an MMC or SD card that contains a more detailed chart for
a particular location, your unit will retrieve that chart and
display it automatically.
931c DF and 931c models have one MMC/SD slot and do
not support cartography.
On any model, use the MMC/SD cards to update the software version of your control
head. To update the software in your control head, plug in the appropriate MMC/SD
card that contains a software update file; the unit will recognize it, will tell you what
software version your control head is currently running, and will ask you if you want to
update the software in the unit to match that on the MMC/SD card. You can obtain
software updates from the www.humminbird.com website.
Use the illustration to locate the position of the MMC and SD slot cover, remove the
cover, and then insert an MMC and/or an SD card into one or both slots - either slot
can accept either an MMC or an SD card. The label on both types of cards should face
down and away from you so that you’re looking at the back of the card. Press down
on the card until it clicks into place, then replace the slot cover and tighten the screw
snugly - do NOT overtighten, as this will not improve water resistance, and may
damage the cover.
Multi-Media Card
(MMC/SD) Slot
2
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3
ACCESSORY BUS
Use the Accessory Bus to expand the functionality of
your 900 Series™. Accessories plug directly into the
900 Series™, enabling Advanced features such as
WeatherSense® and the SmartCast® Wireless Sonar
Link. Additional tabs and menu choices will be added
to the menu system automatically when an accessory
is plugged into the unit. In addition, multiple
accessories can be attached simultaneously. See
Accessories Menu Tab and 900 Series™ Accessories in
this manual, as well as your accessory Operations
Manual for additional details.
NOTE: Accessories to enable WeatherSense® and the SmartCast® Wireless Sonar Link require
separate purchases. You can visit our website at www.humminbird.com or contact our
Customer Resource Center at 1-800-633-1468 for additional details.
INSTALLATION OVERVIEW
Please read all instructions that are relevant for your configuration before beginning
the installation process.
NOTE: Installation procedures will depend on product configuration.
987c
The 900 Series™ has a wide variety of configurations.
Sonar Transducer w/Temperature
1
Optional “Y” Cable
2
NMEA 0183
3
Speed through water
GPS Receiver
WeatherSense®
6
7
8
Power
4SmartCast® Wireless Sonar Link 9
Temperature
5
Accessory Bus
1
2
3
4
5
6
7
8
9
Accessory Bus
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Inside the boat there is often a channel or conduit used for other wiring, this can be
used to route cables. Be sure to route the cable as far as practical from the antenna
cable of VHF radios or tachometer cables to reduce the possibility of interference. The
transducer and GPS receiver cables should not be cut, and care should be used not to
damage the cable insulation.
Basic installation tasks that you must perform include:
•Installing the control head (choosing either gimbal or in-dash mounting)
•Installing the transducer (choosing either the transom mount, inside the hull
mount, or trolling motor mounting method)
•Installing the GPS Receiver (if included)
•Installing the Speed accessory (if included)
•Testing the complete installation and locking the transducer position.
The supplied Humminbird® transducer uses a two piece kick-up mounting bracket. In
addition, if you purchased a 937c DF Combo or 937c Combo model, you will want to
install the included GPS antenna.
NOTE: Accessories may require a separate purchase. You can visit our website at
www.humminbird.com to order these accessories online or contact our Customer Resource
Center at 1-800-633-1468.
CONTROL HEAD INSTALLATION
You have two choices for mounting your 900 Series™ control head:
•Gimbal mounting, where you use a surface on the boat, such as the dash, to
mount the control head so that it can be tilted up or down, or
•In-dash mounting, where you cut a hole in the dash in order to allow the control
head to be recessed into the dash, and the control head cannot be moved after
mounting.
GIMBAL MOUNTING THE CONTROL HEAD
If you are gimbal mounting the Humminbird® 900 Series™, you can pre-assemble the
unit in order to plan the best mounting location.
Parts and tools specific to gimbal mounting are:
• Gimbal mounting bracket and screws
• Gimbal mounting knobs and washers
• Phillips head screwdriver
• 5/16" socket wrench or flat head screw driver
• Hand drill with various drill bits
• Marine-grade silicone sealant.
Washer
1
Gimbal Knob
2
Gimbal Bracket
3
Expansion ports - use for future accessories
4
1
2
3
4
4
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1. Place the control head into the gimbal bracket. Make sure that the straight side
of the gimbal arm is against the back side of the control head.
2. Place a 1" (25 mm) diameter black washer on the gimbal knob and then thread
the knob and washer into the housing. Tighten the gimbal knob to secure the
900 Series™ control head to the mount. Repeat step 2 for the other side.
You can now place the control head in various locations to decide which is best for
mounting. Rotating the mounting bracket to the top of the control head will allow for
overhead mounting. The chosen mounting area should allow for sufficient room so
the control head can pivot through the full tilt range and allow for easy removal and
installation.
NOTE: You can drill the cable pass hole underneath the gimbal bracket, allowing you to
thread the cables through the knock-out holes in the mount; however, if you cannot drill the
hole directly under the mounting bracket, then you will need to drill the cable pass hole
behind the bracket, and will need to mount the hole cover there instead.
NOTE: When drilling holes in fiberglass hulls, it is best to start with a smaller bit and use
progressively larger drill bits to reduce the chance of chipping or flaking the outer coating.
Fill all holes with marine grade silicone sealant.
NOTE: You must have underside access to the mounting location to pass the cables through to
the surface. Also, make sure that the mounting surface is adequately supported to protect the
control head from excessive wave shock and vibration and provide visibility while in operation.
3. After the mounting location has been determined, loosen the gimbal knobs and
remove the control head from the gimbal bracket.
NOTE: Alternate hole patterns are available underneath the gimbal mounting bracket, and
may match existing holes on the boat. If you choose to use one of these alternate hole
patterns, simply drill it out and use it to mount the bracket instead.
4. Place the gimbal bracket in the chosen position on the mounting surface and
mark the four mounting screw locations using a pencil or center punch.
NOTE: Go to the installation instructions applicable to your transducer, GPS Receiver
and accessories. Make the required installations and then run the cables to your control
head mounting location. Do not cut any cabling (except the power cable). If your cables
are too short, extensions are available from your local dealer or online from
www.humminbird.com.
8.5"
5"
3.6"
1.25"
Mounting Screws
1
Washer
2
Gimbal Mounting Bracket
3
1
3
2
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5. Set the gimbal bracket aside and drill the four mounting screw holes using a
5/32" (4.0 mm) drill bit.
6a. If the cables must pass through a hole directly beneath the mounting bracket,
mark and drill an additional 1" (25 mm) hole centered between the four
mounting holes. Route the cables through the grommet, then press the grom-
met in place around the cables and into the 1" (25 mm) hole. Pass the cables out
of the back of the mounting bracket. Using needle-nose pliers, break out the
tabs on the rear of the mounting base. You will need to break out the cable tabs
for the number of cables you want to run to your control head.
6b. If the cables cannot be routed directly beneath the mounting bracket, mark and
drill a 1" (25 mm) hole that will allow you to run the cables close to the bracket.
Pass the cables through the 1" (25 mm) hole, routing the cables through the
grommet and pressing the grommet into place. Place the hole cover over the
mounting surface hole, then use it to mark the position of the two mounting
screws. Remove the hole cover, drill the two mounting holes using a 9/64"
(3.5 mm) bit, fill them with marine-grade silicone, then replace the hole cover
and insert the #8 Phillips countersink wood screws. Hand-tighten only.
7. Place the mounting bracket on the mounting surface aligned with the drilled
holes and fill the mounting holes with marine grade silicone. Insert the four #10
Slotted-Hex wood screws into the mounting holes. Hand-tighten only.
NOTE: Be sure that the cables pass through the slots on the hole cover or gimbal bracket
break out tabs and there is enough cable slack to allow for the control head to pivot through
its full tilt range. Extra cable slack will also help when connecting/disconnecting the cables.
8. Insert cable connectors into the proper recesses on the cable collector insert.
The cable connectors are keyed to prevent reverse installation, so be careful not
to force the connectors into the wrong slots. If you don’t have a cable for every
hole in the insert, install the blank plugs to protect the control head from the
weather.
1
2
Cables Routed Directly Beneath Mounting Bracket
Gimbal Bracket
1
Grommet
2
1
Cables Routed Near Mounting Bracket
Gimbal Bracket
1
Grommet
2
Hole Cover
3
3
2
6
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7
9. While holding cables in place in the cable
collector insert, thread the cables through
the slot in the bottom of the cable collector
cover, line up the cable collector insert and
cover, then slide the cover into place on the
insert.
NOTE: The tab on the Cable Collector insert goes
into the slot on the cover.
10. Attach the cable collector insert to the cable collector cover using the 2 Phillip
screws provided.
11. Place the control head back onto the mounting bracket. Plug in the cable
collector assembly to the back of the control head. Cable connectors and cable
sockets are keyed to prevent reverse installation, so be careful not to force the
connectors into the wrong sockets. Once the cable collector and all cables are
plugged into the back of the control head, lock the assembly into place by
threading the knurled screw into the threaded insert on the back of the housing.
Adjust the control head to the desired viewing angle and secure by tightening
the gimbal knobs.
NOTE: You may wish to dress the cabling with nylon wire ties in order to hold the cables
together and create a cleaner assembly.
The Humminbird® 900 Series™ control head is now ready for operation.
Plug Cable Connector Assembly to
Back of Control Head
Cable Collector Insert
1
Screws
2
Cable Collector Cover
3
Tab on Insert
4
Slot on Cover
5
1
2
3
Power
1
Speed
2
Communications
3
Transducer
4
Cable Collector Insert
5
12 3 4
5
4
5
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IN-DASH MOUNTING THE CONTROL HEAD
If you are in-dash mounting the control head, start by placing the components on the
surfaces where you intend to install them before installation. Make sure that the
surfaces you have chosen provide adequate protection from wave shock, and that all
cables can reach the control head.
NOTE: If a cable is too short for your application, extension cables are available. Call
Humminbird® Customer Support at 1-800-633-1468 for more information.
Parts and tools specific to In-dash mounting are:
• In-dash mount bracket and threaded rods
• In-dash mounting foam pads
• In-dash mounting template
• Reciprocating saw for cutting dash material
• Masking tape to hold mounting template in place.
1. Locate a suitable, flat area of the dash to mount the control head. The control
head requires a depth of at least 3 ½ inches.
2. Tape the paper In-Dash Mounting template to the desired in-dash mounting
location.
3. At a location inside the dotted line on the template, drill a hole large enough to insert
blade of reciprocating saw. Carefully begin cutting toward the dotted line, then
follow the dotted line around the template. Remove the template when finished.
4. Insert and tighten the two threaded rods into the two threaded inserts located
on the back side of the control head. Peel off the adhesive-backed foam pads and
place them on the back of the control head; make sure you notice the difference
between the longer top/bottom and shorter side pads.
5. Insert the control head through the mounting hole from the front side of the
dash. From the back side of the dash, align the two threaded rods on the rear of
the housing with the two holes on the in-dash mounting bracket. Place a
washer onto each threaded rod, then secure bracket by placing a wing nut onto
each threaded rod and tighten fully.
6. Insert cable connectors into the proper recesses on the cable collector insert.
The cable connectors are keyed to prevent reverse installation, so be careful not
to force the connectors into the wrong slots. If you don’t have a cable for every
hole in the insert, install the blank plugs to protect the unit from the weather.
Foam Pads
1
In-Dash Bracket
2
Cut Away Dash
3
Washers
4
Wing Nut
5
Threaded Rod
6
Threaded Insert
7
Expansion ports - use for future accessories
8
1
3
2
4
5
6
7
8
8
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9
7. While holding cables in place in the cable collector insert, thread the cables
through the slot in the bottom of the cable collector cover, line up the cable
collector insert and cover, then slide the cover into place on the insert.
NOTE: The tab on the cable collector insert goes into the slot on the cover.
8. Attach the cable collector insert to the cable collector cover using the 2 Phillip
screws provided.
9. Plug the cable collector assembly into the back of the control head. Cable
connectors and cable sockets are keyed to prevent reverse installation, so be
careful not to force the connectors into the wrong sockets. Once the cable
collector and all cables are plugged into the back of the control head, lock the
assembly into place by threading the knurled screw into the threaded insert on
the back of the housing. (Cable ties are provided to help you secure the cables in
place by threading them through the available holes on the in-dash bracket).
NOTE: It is very important that the cable collector is used and secured in place in the In-Dash
installation.
Cable Collector Insert
1
Screws
2
Cable Collector Cover
3
Tab on Insert
4
Slot on Cover
5
1
2
3
Power
1
Temperature
2
Communications
3
Transducer
4
Cable Collector Insert
5
12 3 4
5
4
5
Plug Cable Connector Assembly to
Back of Control Head
93x_Man_531370-1_A - vs4.qxd 2/18/2005 11:11 AM Page 14

CONNECTING THE CONTROL HEAD POWER CABLE TO THE BOAT
A 6' (2 m) long power cable is included to supply power to the control head. You may
shorten or lengthen the cable using 18 gauge multi-stranded copper wire.
CAUTION: Some boats have 24 or 36 Volt electric systems, but the control head MUST be
connected to a 12 VDC power supply.
The control head power cable can be connected to the electrical system of the boat at one
of two places: a fuse panel usually located near the console, or directly to the battery.
NOTE: Make sure that the power cable is disconnected from the control head at the
beginning of this procedure.
1a. If a fuse terminal is available, use crimp-on type electrical connectors (not
included) that match the terminal on the fuse panel. Attach the black wire to
ground (-), and the red wire to positive (+) 12 VDC power.
1b. If you need to wire the control head directly to a battery, obtain and install an
inline fuse holder and a 2.5 to 3 Amp fuse (not included) for the protection of the
unit. Humminbird® is not responsible for over-voltage or over-current failures.
NOTE: In order to minimize the potential for interference with other marine electronics, a
separate power source (such as a second battery) may be necessary.
You are now ready to install the transducer. Find the section that refers to your specific
transducer installation method.
TRANSDUCER INSTALLATION
There are three different installation methods for your transducer:
• Transom Transducer
• Inside the Hull Transducer
• Trolling Motor Transducer.
Find the section that describes the method of installation you will be using.
NOTE: If the included transducer will not work for your application, you may exchange it,
NEW and UNASSEMBLED, with mounting hardware included, for a transducer appropriate
for your application - often at very little or no charge, depending on the transducer. Call the
Humminbird® Customer Resource Center (1-800-633-1468) for details and pricing, or visit
www.humminbird.com, Product Support/Transducer Exchange for more information.
NOTE: Due to the wide variety of hulls, only general instructions are presented in this
installation guide. Each boat hull represents a unique set of requirements that should be
evaluated prior to installation. In addition to the parts supplied, you will need a hand drill
with various bits, a socket wrench (7/16" or 5/16", depending on transducer type), a Phillips
head screwdriver, and marine-grade silicone sealant.
NOTE: When drilling holes in fiberglass hulls, it is best to start with a smaller bit and use
progressively larger drill bits to reduce the chance of chipping or flaking the outer coating.
Fill all holes with marine grade silicone sealant.
WARNING: Do not touch an active transducer during operation, as this may cause physical
discomfort and may result in personal injury in the form of tissue damage. Handle the
transducer only when the power to the control head is off.
GROUND
POSITIVE
10
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11
TRANSOM TRANSDUCER INSTALLATION
If you will be installing a transom mounted transducer, use the procedures in this section.
You will have one of two different types of transducer, based on whether you have a Single
(931c or 937c Combo) or a Dual (931c DF or 937c DF Combo) frequency 900 Series™ control
head. There are two pieces to the transducer mount assembly: the pivot, and the bracket.
The Single frequency transducer comes with a two-piece plastic bracket assembly, while
theDual frequency transducercomes witha two-piece metaland plasticbracket assembly.
Find the correct procedures for your transducertype. There are several procedures you will
have to perform in order to install a transom-mounted transducer. They are:
•Determine transducer mounting location
•Mount the bracket to the boat (find the procedure for your transducer, either
Single frequency or Dual frequency)
•Attach the pivot to the transducer (find the procedure for your transducer, either
Single frequency or Dual frequency)
•Mount the transducer pivot assembly to the bracket (find the procedure for your
transducer, either Single frequency or Dual frequency)
•Adjust the running position of the transducer (find the procedure for your
transducer, either Single frequency or Dual frequency)
•Route the transducer cable
•Perform a final test of the transom transducer installation.
To determine transducer mounting location:
NOTE: If transom mounting is not possible because of a stepped hull or cavitation noise, and
you have a single layer fiberglass hull, In-hull installation is an option. See Inside the Hull
Transducer Installation for more information.
1. First, determine the best location on the transom to install the transducer.
Consider the following to find the best location:
• It is very important to locate the transducer in an area which is relatively free of
turbulent water. As a boat moves through the water, turbulence is generated by
the weight of the boat, and the thrust of the propeller(s) - either clockwise or
counter-clockwise. This turbulent water is normally confined to areas
immediately aft of ribs, strakes or rows of rivets on the bottom of the boat, and
in the immediate area of the propeller(s). Clockwise propellers create more
turbulence on the port side. On outboard or inboard/outboard boats, it is best to
locate the transducer at least 15" (380 mm) to the side of the propeller(s).
• The best way to locate turbulence-free water is to view the transom while the
boat is moving. This method is recommended if maximum high-speed operation
is a high priority. If this is not possible, select a location on the transom where the
hull forward of this location is smooth, flat and free of protrusions or ribs.
• The hydrodynamic shape of your transducer allows it to point straight down
without deadrise adjustment.
• On boats with stepped hulls, it may be possible to mount the transducer on the
step. Do not mount the transducer on the transom behind a step to avoid
popping the transducer out of the water at higher speeds; the transducer must
remain in the water for the control head to maintain the sonar signal.
• If the transom is behind the propeller(s), it may be impossible to find an area
clear from turbulence, and a different mounting technique or transducer type
should be considered (see Inside the Hull Transducer Installation).
Stepped Hull
Rivets/Strakes
1Deadrise Angle
2Step 3
12
3
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To mount the transducer bracket to the boat (Single frequency unit):
1. Remove the transducer mounting template from this manual. See Appendix A
for the Single Frequency Mounting Template.
NOTE: Please make sure that you use the correct drill holes for the hull composition of
your boat.
2. Hold the template on the transom of
the boat in the location where the
transducer will be installed. Align the
template vertically, matching the lower
edge of the transom with the bottom
corner of the template. If your propeller
moves clockwise as the boat moves
forward, mount the transducer on the
starboard side, and use the bottom left
corner of the template. If your propeller
moves counter-clockwise as the boat
moves forward, mount the transducer on
the port side, and use the bottom right
corner of the template.
3. Using a pencil or punch, mark the two mounting holes (shown on the template
for your type of hull) on the transom. Do not mark or drill any other holes at this
time.
4. Using a 9/64" (3.5 mm) bit, drill the two holes to a depth of approximately
1" (25 mm).
To attach the pivot to the transducer (Single frequency unit):
1. Attach the Two Piece Kick-Up pivot to
the transducer body, using the 1/4" - 20 x
1 1/4" Phillips head pivot bolt, the nyloc
nut, and the two toothed lock washers.
NOTE: The toothed lock washers must be
positioned between the transducer arms
and the pivot knuckle regardless of
mounting bracket type.
2. Using a Phillips screwdriver and a 7/16”
wrench, loosely tighten the pivot bolt. Do
not completely tighten the assembly at
this time, so that the pivot angle can be
adjusted later.
1
Toothed Lock Washer
1
Kick-Up
2
Pivot Knuckle
3
Transducer Arms
4
Pivot Bolt
5
Nyloc Nut
6
1
2
3
45
6
Level 15” (380 mm)
from prop(s)
12
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13
To mount the transducer pivot assembly to the bracket
(Single frequency units):
1. Insert the pivot/transducer assembly into the mounting bracket.
2. Do not snap the assembly closed.
3. Apply marine-grade silicone sealant to the mounting holes drilled into the
transom.
4. Align the transducer assembly with the drilled holes in the transom.
5. Using the appropriate tool for your mounting hardware,
attach the transducer assembly to the boat transom as
shown, using #8 x 5/8” (16 mm) wood screws. Do not fully
tighten the mounting screws in order to adjust the
transducer vertically. Snap the pivot down into place.
NOTE: The running position of the transducer is now
completely adjustable. Subsequent adjustment may be
necessary to tweak the installation after high speed testing.
To adjust the running position of the transducer (Single frequency unit):
The transducer mounting bracket allows height and tilt adjustment, while the pivot
bolt allows angular adjustment. These adjustments will help reduce cavitation.
Initially, adjust the transducer as described in the following paragraphs. Further
adjustment may be necessary to refine the installation after high-speed testing.
1. First, adjust the pivot angle of the transducer body, so its length is parallel with
the length of the hull of the boat. Then, using the angle portion of the mounting
template, pivot the transducer down so that it matches the template angle as
shown on the template itself.
2. Fully tighten the pivot bolt, using a Phillips head screwdriver and a wrench. It
may be necessary to re-tighten the pivot bolt after initial use as the plastic may
still be conforming to the pressure from the lock washers.
3. Before removing the template, adjust the height of the assembly so the face of
the transducer touches the face of the template. Mark the position of the
mounting bracket on the transom with a pencil.
4. Force the pivot to the Up position to gain access to the mounting screws. Make
sure that the transducer location has not changed, then hand tighten the two
mounting screws. Snap the pivot back down.
5. Confirm that the pivot angle has not changed.
NOTE: when you are done with this procedure, go to the section entitled: To route the
transducer cable.
Normal Cavitation Cavitation that will cause
erratic sonar readings
1
Kick-Up Bracket
1
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To mount the transducer
bracket to the boat
(Dual frequency unit):
1. Remove the transducer mounting
template from this manual. See
Appendix B for the Dual Frequency
Transducer Mounting Template.
2. Hold the template on the transom of
the boat in the location where the
transducer will be installed. Align the
template vertically, matching the lower
edge of the transom with the bottom
corner of the template. If your propeller
moves clockwise as the boat moves
forward, mount the transducer on the
starboard side, and use the bottom left
corner of the template. If your propeller
moves counter-clockwise as the boat
moves forward, mount the transducer on
the port side, and use the bottom right
corner of the template.
3. Using a pencil or punch, mark the three mounting holes on the transom. Do not
mark or drill any other holes at this time.
4. Using a 5/32" (4.0 mm) bit, drill the three holes to a depth of approximately
1" (25 mm). On fiberglass hulls, it is best to use progressively larger drill bits to
reduce the chance of chipping or flaking the outer coating. Use a marine-grade
silicone sealant to fill the drilled holes.
5. Align the metal mounting bracket with the mounting
holes. The center slot should be above the two outer
slots. (This bracket and all other hardware supplied is top
quality stainless steel for maximum strength and
corrosion protection.) Insert the three 1" (25 mm) flat
head wood screws into the drilled holes, but do not
completely tighten.
To attach the pivot to the transducer (Dual frequency unit):
1. Attach the pivot to the transducer body, using the two 1/4"-20 x 5/8" (16 mm)
machine screws, toothed washers, and square nuts. The toothed washers must
fit on the inside of the transducer ears, between the pivot and the ears. The
square nuts will be prevented from rotating by the pocket in the back of the
pivot. An Allen wrench is provided which fits all the 1/4"-20 screws, but do not
fully tighten the screws at this time.
Attach the Pivot
2
3
4
1
Insert the square nuts
1
Toothed Washer
2
Pivot
3
Machine Screw
4
Attaching the Bracket
Level 15” (380 mm)
from prop(s)
14
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15
To mount the transducer pivot assembly to the bracket
(Dual frequency units):
1. Slide the assembled transducer into the metal bracket from the bottom,
aligning the large hole at the top of the bracket with the hole in the pivot.
2. Insert the headed pin through the pivot holes in the bracket and pivot. The
headed pin can be inserted from either side of the bracket.
3. Place the nylon washer over the opposite end of the headed pin. Place the
stainless washer over the 1/4"-20 x 5/8" screw threads, then insert into the
opposite end of the headed pin and finger tighten only. The screw has a thread
locking compound on the threads to prevent loosening, and should not be fully
tightened until all adjustments are made.
NOTE: The running position of the transducer is now completely adjustable. Subsequent
adjustment may be necessary to tweak the installation after high speed testing.
To adjust the running position of the transducer
(Dual frequency units):
The transducer mounting bracket allows height and tilt adjustment, while the pivot
bolt allows angular adjustment. These adjustments will help reduce cavitation.
Initially, adjust the transducer as described in the following paragraphs. Further
adjustment may be necessary to refine the installation after high-speed testing.
1. First, adjust the pivot angle of the transducer body, so it is parallel with the
length of the hull of the boat.
2. Fully tighten the two pivot screws, using the supplied Allen wrench. Access to
the pivot screws is provided by the lower holes in the side of the mounting
bracket. It may be necessary to re-tighten the pivot bolt after initial use as the
plastic may still be conforming to the pressure from the lock washers.
3. Adjust the height of the assembly so the face of the
transducer is 1/8" (3 mm) to 1/4" (6 mm) beneath the
bottom of the transom, and fully tighten the three
mounting screws.
4. In order to gain access to the mounting screws, the
transducer assembly must be pivoted up in the bracket as
shown. Be careful not to alter the running angle as some
force is necessary to pivot the assembly.
Tighten the Mounting Screws
Cavitation that will cause
erratic sonar readings
Normal Cavitation
Screw
1
Headed Pin
2
Allen Wrench
3
Nylon Washer
4
Stainless Washer
5
3
15
4
2
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