Humminbird 688ci HD DI User manual

532174-1EN_A
688ci HD, 688ci HD DI, and
688ci HD XD Combo
Operation Manual
688ci HD, 688ci HD DI, and
688ci HD XD Combo
Operation Manual

Thank You!
Thank you for choosing Humminbird®, the #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 separate warranty card included with your unit. We
encourage you to read this operations manual carefully in order to get the full
benefit from all the features and applications of your Humminbird® product.
Contact our Customer Resource Center at 1-800-633-1468 or visit our Web
site at 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! The electronic chart in your Humminbird® unit is an aid to navigation
designed to facilitate the use of authorized government charts, not to replace them.
Only official government charts and notices to mariners contain all of the current
information needed for the safety of navigation, and the captain is responsible for their
prudent use.
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.
WARNING! This product contains chemicals known to the State of California to
cause cancer and/or reproductive harm.
WARNING! Do not travel at high speed with the unit cover installed. Remove the unit
cover before traveling at speeds above 20 mph.
WARNING! Humminbird® is not responsible for the loss of data files (waypoints,
routes, tracks, groups, recordings, etc.) that may occur due to direct or indirect damage
to the unit’s hardware or software. t is important to back up your control head’s data
files periodically. Data files should also be saved to your PC before restoring the unit’s
defaults or updating the software. See the following sections of your Humminbird®
manual: Snapshot and Recording View and SD Memory Card Slot. Also, contact our
Customer Resource Center with any questions.

N TE: The illustrations in this manual may not look exactly like the display on your
Humminbird®model, but your model will work in the same way.
N TE: Some features discussed in this manual require a separate purchase, and some
features are only available on international models. Every effort has been made to
clearly identify those features. Please read the manual carefully in order to understand
the full capabilities of your model.
N TE: To purchase accessories for your fishfinder, visit our Web site at
humminbird.com or contact our Customer Resource Center at 1-800-633-1468.
N TE: The procedures and features described in this manual are subject to change
without notice. This manual was written in English and may have been translated to
another language. Humminbird® is not responsible for incorrect translations or
discrepancies between documents.
R HS STATEMENT: Product designed and intended as a fixed installation or part of
a system in a vessel may be considered beyond the scope of Directive 2002/95/EC of
the European Parliament and of the Council of 27 January 2003 on the restriction of
the use of certain hazardous substances in electrical and electronic equipment.
600 Series™, own Imaging®, ualBeam PLUS™, Fish I +™, HumminbirdPC™, Humminbird®,
LakeMaster®, Real Time Sonar™, RTS™, RTS Window™, Structure I ™, SwitchFire®, Total Screen
Update™, UniMap™, WhiteLine™, X-Press™ Menu, and Xtreme epth Series™ are trademarked
by or registered trademarks of Johnson Outdoors Marine Electronics, Inc.
Adobe, Acrobat, Adobe P F, and Reader are either registered trademarks or trademarks of Adobe
Systems Incorporated in the United States and/or other countries.
Baekmuk Batang, Baekmuk otum, Baekmuk Gulim, and Baekmuk Headline are registered
trademarks owned by Kim Jeong-Hwan.
Navionics® Gold, HotMaps™, and HotMaps™ Premium are registered trademarks of Navionics®.
© 2013 Johnson Outdoors Marine Electronics, Inc. All rights reserved.
ATTENTION INTERNATIONAL CU TOMER : Pro ucts sol in the U.S. are not
inten e for use in the international market. Humminbir ® international units
provi e international features an are esigne to meet country an regional
regulations. Languages, maps, time zones, units of measurement, an warranty
are examples of features that are customize for Humminbir ® international units
purchase through our authorize international istributors.
To obtain a list of authorize international istributors, please visit our Web site at
humminbird.com or contact our Customer Resource Center at [phone].

Power On 1
How Sonar Works 2
ualBeam PLUS™ Sonar (DualBeam PLUS™models only [688ci HD]) ........................ 4
own Imaging® Sonar
(Down maging® models only [688ci HD D ]) .............................................................. 5
Xtreme epth Sonar (Xtreme Depth Series™ models only [688ci HD XD]) .................... 6
ual Beam Ice Transducer (with optional-purchase X 9 20 ce Transducer).................. 7
How GPS Works 8
What’s on the 600 Series™ Control Head 9
Key Functions 10
POWER/LIGHT Key .............................................................................................. 10
VIEW Key .............................................................................................................. 10
CHECK/INFO key.................................................................................................... 11
MENU Key ............................................................................................................ 11
4-WAY Cursor Control Key .................................................................................. 12
VIEW PRESET Keys................................................................................................ 13
MARK Key.............................................................................................................. 13
GOTO Key................................................................................................................ 13
ZOOM (+/-) Key .................................................................................................... 14
EXIT Key ................................................................................................................ 14
SD Memory Card Slot 15
Add Maps to Your Fishfinder ................................................................................ 16
Import Navigation ata ........................................................................................ 17
Export Navigation ata ........................................................................................ 17
Update Software.................................................................................................... 19
What’s on the Sonar Display 20
Understanding the Sonar isplay ........................................................................ 22
Real Time Sonar (RTS™) Window ........................................................................ 22
Table of Contents
i

Sonar Colors and Bottom View ............................................................................ 23
SwitchFire® ............................................................................................................ 25
Freeze Frame and Active Cursor .......................................................................... 25
Instant Image Update............................................................................................ 25
What’s on the Down Imaging® Display
(Down Imaging® models only [688ci HD DI]) 26
Understanding the own Imaging® isplay ........................................................ 28
Interpreting the isplay ........................................................................................ 28
own Imaging® Sensitivity .................................................................................. 29
Freeze Frame and Active Cursor .......................................................................... 29
Views 30
Sonar View ............................................................................................................ 32
Sonar Zoom View ................................................................................................ 33
Split Sonar View .................................................................................................... 34
Big igits View ...................................................................................................... 36
own Imaging® View (Down maging® models only [688ci HD D ]) ............................ 37
Circular Flasher View ............................................................................................ 39
Snapshot and Recording View.............................................................................. 44
Bird’s Eye View ...................................................................................................... 50
Chart View.............................................................................................................. 51
Combo View .......................................................................................................... 53
Chart/ own Combo View
(Down maging® models only [688ci HD D ]) ............................................................ 54
own/Sonar Combo View
(Down maging® models only [688ci HD D ]) ............................................................ 55
View Orientation.................................................................................................... 56
Viewing Cartography ............................................................................................ 57
Introduction to Navigation 60
Waypoints, Routes, and Tracks ............................................................................ 60
Open the Waypoint Management ialog Box .................................................... 62
ii
Table of Contents

iii
Table of Contents
What’s on the Waypoint Management ialog Box ............................................ 63
Save, Create, or elete a Waypoint...................................................................... 65
Navigate to a Waypoint or Position...................................................................... 66
Add a Waypoint Target or Trolling Grid................................................................ 67
Routes .................................................................................................................... 68
Tracks .................................................................................................................... 70
Edit your Waypoints, Routes, Tracks, and Groups .............................................. 71
he Menu System 73
Start-Up Options Menu 74
Normal .................................................................................................................. 74
Simulator .............................................................................................................. 75
System Status ...................................................................................................... 75
Self Test.................................................................................................................. 76
Accessory Test ...................................................................................................... 76
GPS iagnostic View ............................................................................................ 77
X-Press™ Menu 78
Main Menu 79
Quick Tips for the Main Menu.............................................................................. 80
Note for all Menu Settings .................................................................................. 80
User Mode (Normal or Advanced)........................................................................ 81
Sonar X-Press™ Menu (Sonar Views only) 83
Cancel Navigation (only when Navigating) .............................................................. 84
Sensitivity .............................................................................................................. 84
Upper Range (Advanced: Sonar, Split Sonar, Circular Flasher, and Big Digits Views only) 85
Lower Range ........................................................................................................ 85
Chart Speed .......................................................................................................... 86
Bottom Range (Sonar Zoom View only when Bottom Lock is On) ................................ 87
Bottom Lock (Sonar Zoom View only)........................................................................ 87
Reset XTE (only when Navigating) ............................................................................ 87

iv
Table of Content
D wn Imaging® X-Press™ Menu
(D wn Imaging® Views nly [688ci HD DI]) 88
Cancel Navigation (only when Nav gat ng) .............................................................. 89
Down Sensitivity.................................................................................................... 89
DI Enhance ............................................................................................................ 90
Upper Range (Advanced) ........................................................................................ 91
Lower Range.......................................................................................................... 91
Chart Speed .......................................................................................................... 92
Reset XTE (only when Nav gat ng) ............................................................................ 92
DI Colors ................................................................................................................ 92
Flasher X-Press™ Menu (Circular Flasher View nly) 93
Cancel Navigation (only when Nav gat ng) .............................................................. 94
Sensitivity .............................................................................................................. 94
Upper Range (Advanced) ........................................................................................ 94
Lower Range ........................................................................................................ 95
Color Palette (C rcular Flasher V ew, Ice F sh ng Mode only) ........................................ 96
Reset XTE (only when Nav gat ng) ............................................................................ 96
Snapsh t and Rec rding X-Press™ Menu
(Snapsh t and Rec rding View nly) 97
Start Recording (opt onal-purchase SD Memory Card,
Snapshot and Record ng V ew only) ........................................................................ 98
Stop Recording (opt onal-purchase SD Memory Card only) ........................................ 98
Delete Image (opt onal-purchase SD Memory Card,
Snapshot and Record ng V ew only) ........................................................................ 98
Delete All Images (opt onal-purchase SD Memory Card,
Snapshot and Record ng V ew only) ........................................................................ 98
Delete Recording (opt onal-purchase SD Memory Card,
Snapshot and Record ng V ew only) ........................................................................ 99
Delete All Recordings (opt onal-purchase SD Memory Card,
Snapshot and Record ng V ew only) ........................................................................ 99
Pings Per Second (opt onal-purchase SD Memory Card,
Snapshot and Record ng V ew only) ........................................................................ 99

v
Table of Content
Playback Speed (opt onal-purchase SD Memory Card,
Snapshot and Record ng V ew only) ...................................................................... 100
Stop Playback (opt onal-purchase SD Memory Card only) ........................................ 101
Navigati n X-Press™ Menu (Navigati n Views nly) 102
Cancel Navigation (only when Nav gat ng) ............................................................ 103
Skip Next aypoint (only when Nav gat ng) .......................................................... 103
aypoint [Name] (only w th an act ve cursor on a waypo nt) .................................. 103
Cursor To aypoint (Chart or Combo V ew only) .................................................... 104
Chart Declutter .................................................................................................... 104
Save Current Track .............................................................................................. 104
Clear Current Track.............................................................................................. 104
Save Current Route (only when Nav gat ng) .......................................................... 105
Sonar indow (Combo V ew and Chart/Down Combo V ew only) ............................ 105
Reset XTE (only when Nav gat ng) .......................................................................... 105
Remove Target (only f a Target s Act ve) ................................................................ 105
Remove Grid (only f a Gr d s Act ve) ...................................................................... 106
aypoint [Name] (Most recently-created waypo nt) ................................................ 106
Alarms Menu Tab 107
Depth Alarm ........................................................................................................ 108
Fish ID Alarm ...................................................................................................... 108
Low Battery Alarm .............................................................................................. 108
Temp. Alarm (w th opt onal-purchase Temp/Speed only) .......................................... 109
Off Course Alarm ................................................................................................ 109
Arrival Alarm........................................................................................................ 110
Drift Alarm .......................................................................................................... 110
Alarm Tone .......................................................................................................... 110
Timer Setup.......................................................................................................... 111
Start Timer .......................................................................................................... 111
Stop Timer (w th the T mer runn ng)........................................................................ 111

vi
Table of Contents
Sonar Menu ab 112
Beam Select ........................................................................................................ 113
Imaging Frequency (Down maging® Views only [688ci HD D ]) ................................ 115
Surface Clutter .................................................................................................... 116
SwitchFire® .......................................................................................................... 116
Fish I +™ ............................................................................................................ 117
Fish I Sensitivity ................................................................................................ 118
Real Time Sonar (RTS™) Window...................................................................... 118
Sonar Colors (Sonar View, Sonar Zoom View,
Circular Flasher View, Big Digits View, and Sonar Combo Views).............................. 119
Bottom View ........................................................................................................ 119
Zoom Width ........................................................................................................ 120
50 kHz Sensitivity (Advanced, XD Sonar only [688ci HD XD]) .................................... 120
83 kHz Sensitivity (Advanced, DualBeam PLUS™ Sonar only [688ci HD]) .................. 120
455 kHz Sensitivity (Advanced, Down maging® Views only [688ci HD D ])..................120
epth Lines (Advanced) ........................................................................................ 121
Noise Filter (Advanced).......................................................................................... 121
Max epth (Advanced) .......................................................................................... 122
Water Type (Advanced).......................................................................................... 122
igital epth Source (Advanced, Down maging® models with
optional-purchase transducers only [688ci HD D ]) .................................................. 123
I Pings (Advanced, Down maging® View and Chart/Down maging®
Combo View only [688ci HD D ])............................................................................ 124
Ice Fishing Mode ................................................................................................ 125
I Colors (Down maging® Views only [688ci HD D ]) ................................................ 125
Navigation Menu ab 126
Current Track........................................................................................................ 127
Waypoints, Routes, Tracks (Waypoint Management Dialog Box) ............................ 128
Waypoint Settings .............................................................................................. 128
Saved Tracks efault .......................................................................................... 129

vii
Table of Contents
Chart Orientation ................................................................................................ 129
Casting Rings (Advanced)...................................................................................... 129
North Reference .................................................................................................. 130
Waypoint Proximity Flags (Advanced) .................................................................. 130
Waypoint ecluttering (Advanced) ...................................................................... 131
Trolling Grid Rotation .......................................................................................... 131
Trackpoint Interval .............................................................................................. 131
Track Min istance (Advanced) ............................................................................ 132
Track Color Range................................................................................................ 132
Map atum (Advanced) ........................................................................................ 132
North-Up Indicator .............................................................................................. 132
Course Projection Line ........................................................................................ 133
Continuous Navigation Mode ............................................................................ 133
Chart Menu ab 134
Lat/Lon Grid ........................................................................................................ 135
Navaids on Bird’s Eye View ................................................................................ 135
Chart Select ........................................................................................................ 135
Set Simulation Position (Advanced)...................................................................... 135
Set Map Offset (Advanced) .................................................................................. 136
Clear Map Offset (Advanced)................................................................................ 136
Shaded epth...................................................................................................... 136
Chart etail Level ................................................................................................ 137
Map Borders........................................................................................................ 138
Spot Soundings .................................................................................................. 138
Auto Zoom (Advanced) .......................................................................................... 139
Auto Range (Advanced) ........................................................................................ 139
Vessel Offset ...................................................................................................... 139
Offset Speed (with Vessel Offset turned on) ............................................................ 140
Contour Lines (optional-purchase LakeMaster® charts only)...................................... 140
epth Colors (optional-purchase LakeMaster® charts only)........................................ 140
epth Highlight (optional-purchase LakeMaster® charts only) .................................. 140

viii
Table of Contents
epth Highlight Range (+/-) (optional-purchase LakeMaster® charts only) .............. 141
Water Level Offset (optional-purchase LakeMaster® charts only) ..............................141
Shallow Water Highlight (optional-purchase LakeMaster® charts only) .................... 141
Lake List (optional-purchase LakeMaster® charts only) .............................................. 142
Setup Menu ab 143
Units - epth ...................................................................................................... 144
Units - Temp ( nternational only) ............................................................................ 144
Units - istance .................................................................................................. 144
Units - Speed ...................................................................................................... 144
User Mode .......................................................................................................... 144
Language ( nternational Models only)...................................................................... 145
Triplog Reset ...................................................................................................... 145
Restore efaults .................................................................................................. 145
Select Views (Advanced) ...................................................................................... 145
Format Nav irectories........................................................................................ 146
Select Readouts (Advanced, Sonar View and Down maging® View only) .................. 146
epth Offset (Advanced)........................................................................................ 147
Temp. Offset (Advanced, with Temp/Speed only)...................................................... 148
Speed Calibration (Advanced, with Temp/Speed only) ............................................ 148
Local Time Zone (Advanced).................................................................................. 148
aylight Saving Time (Advanced).......................................................................... 148
Position Format (Advanced) .................................................................................. 149
Time Format (Advanced, nternational only) ............................................................ 149
ate Format (Advanced, nternational only).............................................................. 149
igits Format (Advanced) ...................................................................................... 149
NMEA 0183 Output (Advanced)............................................................................ 150
Sonar .................................................................................................................... 150
emonstration .................................................................................................... 151
Sound Control...................................................................................................... 151
Screen Snapshot.................................................................................................. 151

ix
Table of Contents
Maintenance 152
roubleshooting 154
Fishfinder oesn’t Power Up .............................................................................. 154
Fishfinder efaults to Simulator with a Transducer Attached.......................... 154
isplay Problems ................................................................................................ 155
Finding the Cause of Noise ................................................................................ 156
Specifications 157
Glossary 161
Contact Humminbird® 169
N TE: Entries in this Table of Contents which list ( nternational 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
[phone].
N TE: Entries in this Table of Contents which list (with Temp/Speed only)
require the purchase of separate accessories. Visit our Web site at
humminbird.com to order these accessories online or contact our Customer
Resource Center at 1-800-633-1468.
N TE: Some features discussed in this manual require a separate purchase,
and some features are only available on international models. Every effort has
been made to clearly identify those features. Please read the manual carefully
in order to understand the full capabilities of your model.

Power On
Follow the instructions below to power on your Humminbird® control head.
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. If a functioning transducer is connected, Normal operation will be
selected automatically, and your Fishfinder can be used on the water.
See Start-Up ptions Menu for more information.
•If a transducer is not connected and you wait too long to select a
Start-Up Option, the system will default to whichever menu is
already highlighted.
• You can also select Simulator to learn how to use your control
head and save settings in advance for later use.
4. Quick Setup: If this is the first time the unit has been powered on (after
installation or after restoring defaults), the Quick Setup dialog box will
display on the screen. Use the 4-WAY Cursor Control key to set the
Language, Water Type, and Max epth. Press the EXIT key to close the
dialog box.
688ci HD Combo Title creen
1Power On

2
N TE: The Quick Setup settings can be changed at any time. See each menu
option in The Menu System for details.
How Sonar Works
Sonar technology is based on sound waves. The 600 Series™ Fishfinder uses
sonar to locate and define structure, bottom contour and composition, as well
as depth directly below the transducer.
Your 600 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; 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 1/4 of a second. It is unlikely that your
boat can “outrun“ this sonar signal.
SONAR is an acronym for SOund and
NAvigation Ranging. Sonar utilizes precision
sound pulses or “pings“ which are emitted
into the water in a teardrop-shaped beam.
The sound pulses “echo“ back from objects
in the water such as the bottom, fish, and
other submerged objects. The returned
echoes are displayed on the LC screen.
Each time a new echo is received, the old
echoes are moved across the LC , creating
a scrolling effect.
How Sonar Wor s

3How Sonar Wor s
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. High
frequencies (200 kHz) are commonly used on
consumer sonar and provide a good balance
between depth performance and resolution. Low
frequencies (83 kHz) are typically used to achieve
greater depth capability.
The power output is the amount of energy
generated by the sonar transmitter. It is commonly
measured using two methods:
• Root Mean Square (RMS) measures power
output over the entire transmit cycle.
• Peak to Peak measures power output at the
highest points.
The benefits of increased power output are the
ability to detect smaller targets at greater distances,
ability to overcome noise, better high speed
performance, and enhanced depth capability.

4
DualBeam PLUS™ Sonar
(DualBeam PLUS™ models only [688ci HD])
Your 688ci HD Fishfinder uses a 200/83 kHz
ualBeam PLUS™ sonar system with a wide (60°)
area of coverage. ualBeam 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. In 20 feet of
water, the wider beam covers an area 20 feet
wide.
ualBeam PLUS™ sonar returns can be blended
together, viewed separately, or compared side-
by-side. ualBeam PLUS™ is ideal for a wide
range of conditions - from shallow to very deep
water in both fresh and salt water. epth
capability is affected by such factors as boat
speed, wave action, bottom hardness, water
conditions, and transducer installation.
How Sonar Wor s

5How Sonar Wor s
Down Imaging® Sonar
(Down Imaging® models only [688ci HD DI])
Your 688ci HD DI Fishfinder uses own
Imaging® technology. The own Imaging®
transducer scans the water with razor-thin,
high-definition beams. The beams are wide
(side to side) but very thin front to back.
The own Imaging® beams can be operated
at two frequencies: 455 kHz (75°) or 800 kHz
(45°). Select 455 kHz for the best overall
image quality and depth. Select 800 kHz for
the sharpest image. See Sonar Menu Tab:
Imaging Frequency for more information.
The transducer also uses conical beams to
provide data in traditional 2 format (see
What’s on the Sonar Display). Select 455 kHz
for a narrowly focused 16° center beam, or
select 200 kHz for a wider 25° beam (see Sonar
Menu Tab: Beam Select).
epth capability is affected by such factors
as boat speed, wave action, bottom hardness,
water conditions, and transducer installation.
75 Degree Total Coverage
16°
75°
25°
455kHz
200kHz
455kHz
45° 800kHz

6
Xtreme Depth Sonar
(Xtreme Depth Series™ models only [688ci HD XD])
Your 688ci HD XD Fishfinder uses the X
transducer to provide extreme depth coverage
with ualBeam PLUS™ technology.
The Xtreme epth sonar beams can be operated
at two frequencies: 50 kHz (74°) and 200 kHz
(20°). The wide, 50 kHz beam transmits at a low
frequency to provide greater depth coverage, up
to 2500 ft (762 m). The narrow, 200 kHz center
beam transmits at a high frequency to provide
maximum detail at shallower depths.
The ualBeam PLUS™ technology allows you to
view the sonar returns blended together,
separately, or side-by-side (see Sonar Menu
Tab: Beam Select and Views for more
information).
epth capability is affected by such factors as
boat speed, wave action, bottom hardness,
water conditions and transducer installation.
How Sonar Wor s

7
Dual Beam Ice Transducer
(with optional-purchase XI 9 20 Ice
Transducer)
The XI 9 20 Ice Transducer 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. The
20° center beam provides the highest
definition, while the 60° beam provides
wider coverage. epth capability is
affected by such factors as bottom
hardness and water conditions. Whether
fishing in shallow or very deep water,
selectable dual-frequency is ideal for a
variety of conditions.
N TE: Contact our Customer Resource
Center to determine which accessory
transducers are compatible with your
Humminbird® Fishing System, or visit our
Web site at humminbird.com.
How Sonar Wor s

8
How GPS Works
Your 600 Series™ Fishfinder also supports GPS (Global Positioning System) and
chartplotting. It uses GPS and sonar to determine your position, display it on a
grid, and provide detailed underwater information.
GPS uses a constellation of satellites that
continually send radio signals to the earth. The
GPS receiver on your boat receives signals from
satellites that are visible to it. Based on time
differences between each received signal, the GPS
receiver determines its distance to each satellite.
With distances known, the GPS receiver
mathematically triangulates its own position. With
5 updates per second, the GPS receiver then
calculates its velocity and bearing.
GPS was originally intended for military use; however, civilians may also take
advantage of its highly accurate position capabilities, typically within +/- 4.5
meters, depending on conditions. This means that 95% of the time, the GPS
receiver will read a location within +/- 4.5 meters of your actual position. Your
GPS Receiver also uses information from WAAS (the Wide Area Augmentation
System), EGNOS (the European Geostationary Navigations Overlay Service),
and MSAS (the MTSAT Satellite Augmentation System) satellites if they are
available in your area.
The following GPS functionality is currently supported by the 600 Series™
Fishfinder when it is connected to the included 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
See Chart View and SD Memory Card Slot: Add Maps to Your Fishfinder for
more information.
How GPS Wor s