Lowrance LMS339C, LMS334C User Manual

www.lowrance.com

Pub. 988-0152-111

LMS-334c iGPS &

LMS-339cDF iGPS

Fish-finding Sonar & Mapping GPS

Installation and Operation

Instructions

Copyright © 2006 Lowrance Electronics, Inc.

All rights reserved.

No part of this manual may be copied, reproduced, republished, transmitted or
distributed for any purpose, without prior written consent of Lowrance
Electronics. Any unauthorized commercial distribution of this manual is

strictly prohibited.



Lowrance
MapCreate, FreedomMaps, IMS and NauticPaths are
trademarks of LEI. Fishing Hot Spots
Fishing Hot Spots Inc. Navionics

is a registered trademark of Lowrance Electronics, Inc.



is a registered trademark of



is a registered trademark of

Navionics, Inc.

eXitSource Database, copyright  2001-2005 Zenrin Co.
Ltd. Exit Authority and eXitSource are trademarks of
Zenrin Co. Ltd.

Lowrance Electronics may find it necessary to change or end our
policies, regulations and special offers at any time. We reserve the right
to do so without notice. All features and specifications subject to change
without notice. All screens in this manual are simulated. On the cover:
LMS-339cDF iGPS shown.

For free owner's manuals and other information,

visit our web site:

www.lowrance.com

Lowrance Electronics Inc.

12000 E. Skelly Dr.

Tulsa, OK USA 74128-2486

Printed in USA.

Table of Contents

Section 1: Read Me First!......................................................... 1

Capabilities and Specifications: .................................................... 3

How to use this manual: typographical conventions ................ 10

Arrow Keys.............................................................................. 12

Keyboard ................................................................................. 12

Menu Commands .................................................................... 12

Instructions = Menu Sequences ............................................. 12

Section 2: Installation & Accessories.................................. 13

Preparations................................................................................ 13

Transducer Installation.............................................................. 13

Recommended Tools and Supplies ......................................... 14

Single-frequency transom installations ............................. 14

Dual-frequency transom installations ............................... 14

Single-frequency trolling motor installations.................... 14

Shoot-through hull installations ........................................ 14

Selecting a Transducer Location............................................ 14

How low should you go?.......................................................... 16

Shoot-Thru-Hull vs. Transom Mounting ............................... 16

Transom Transducer Assembly and Mounting ..................... 17

Trolling Motor Bracket Installation (single-frequency only) 22

Transducer Orientation and Fish Arches .............................. 23

Shoot-Thru-Hull Preparation................................................. 24

Testing Determines Best Location......................................... 24

Shoot-Thru-Hull Installation ................................................. 26

Speed/Temperature Sensors ................................................. 28

Optional Speed Sensor Installation ....................................... 28

Power Connections...................................................................... 29

Powering a NMEA 2000

GPS Internal Antenna................................................................ 32

NMEA 2000 Cable Connections ................................................. 32

Connecting to a NMEA 2000 Network................................... 33

NMEA 0183 Wiring ................................................................ 33

Mounting the Unit: Bracket or Portable.................................... 35

MMC or SD Card Memory Card Installation ............................ 38

Other Accessories........................................................................ 39

Face Cover................................................................................... 40

Section 3: Basic Sonar Operation ........................................ 41

Keyboard ..................................................................................... 41

Power/lights on and off ............................................................... 42

Main Menu .................................................................................. 42

Pages ........................................................................................... 43

Satellite Status Page .............................................................. 44

®

Buss .................................................. 30

i

Navigation Page...................................................................... 45

Map Page................................................................................. 45

SonarPage ............................................................................... 46

Basic Sonar Quick Reference ...............................................49

Sonar Operations ........................................................................ 50

Fish Symbols vs. Full Sonar Chart ........................................ 52

Other Free Training Aids ....................................................... 53

Section 4: Sonar Options & Features.................................. 55

ASP (Advanced Signal Processing) ......................................... 55

Alarms ......................................................................................... 56

Depth Alarms .......................................................................... 56

Zone Alarm .............................................................................. 57

Fish Alarm............................................................................... 58

NMEA 2000 Alarm ..................................................................... 58

Calibrate Speed........................................................................... 59

Chart Speed................................................................................. 59

ColorLine.................................................................................. 60

Depth Cursor............................................................................... 61

Depth Range - Automatic ........................................................... 62

Depth Range - Manual................................................................ 63

Depth Range - Upper and Lower Limits ................................... 63

FasTrack .................................................................................. 65

Fish I.D. ................................................................................... 65

FishTrack ................................................................................. 66

Frequency (LMS-339cDF only) .................................................. 68

HyperScroll .............................................................................. 69

Log Sonar Chart Data ................................................................ 69

NMEA 2000................................................................................. 70

Noise Rejection............................................................................ 70

Overlay Data ............................................................................... 70

Ping Speed & HyperScroll....................................................... 74

Reset Options .............................................................................. 76

Reset Water Distance ................................................................. 76

Set Keel Offset ............................................................................76

Sensitivity & Auto Sensitivity.................................................... 78

Sonar Chart Mode....................................................................... 79

Sonar Page & Sonar Chart Display Options ............................. 79

Full Sonar Chart ..................................................................... 80

Split Zoom Sonar Chart.......................................................... 81

Split Frequency Sonar Chart (LMS-339cDF only) ................ 81

Digital Data/Chart .................................................................. 82

Customize Page Displays........................................................ 82

Flasher..................................................................................... 83

ii

Map With Sonar Split Screen................................................. 84

Sonar Simulator.......................................................................... 84

Stop Chart ................................................................................... 86

Surface Clarity............................................................................ 87

Transparency ..............................................................................88

Upper and Lower Limits ............................................................ 89

Zoom & Zoom Bar ....................................................................... 89

Zoom Pan..................................................................................... 89

Section 5: Sonar Troubleshooting .......................................91

Section 6:Basic GPS Operations .......................................... 95

Keyboard ..................................................................................... 95

Power/lights on and off ............................................................... 96

Main Menu .................................................................................. 96

Pages ........................................................................................... 97

Sonar Page .............................................................................. 98

Satellite Status Page .............................................................. 98

Navigation Page.................................................................... 100

Map Page............................................................................... 103

Background map vs. MapCreate map content .................... 104

Basic GPS Quick Reference ................................................ 108

Find Your Current Position...................................................... 109

Moving Around the Map: Zoom & Cursor Arrow Keys ........... 109

Selecting Map Item With the Cursor....................................... 110

Searching................................................................................... 110

Set a Waypoint.......................................................................... 112

Navigate To a Waypoint ........................................................... 114

Set Man Overboard (MOB) Waypoint...................................... 115

Navigate Back to MOB Waypoint ............................................ 115

Navigate to Cursor Position on Map........................................ 116

Navigate to a Point of Interest................................................. 117

Creating and Saving a Trail..................................................... 117

Displaying a Saved Trail .......................................................... 119

Navigating Trails...................................................................... 120

Visual Trailing ...................................................................... 120

Navigate a Trail .................................................................... 120

Navigate a Back Trail........................................................... 122

Transfer Custom Maps and GPS Data Files ....................... 123

Cancel Navigation..................................................................... 125

Section 7: Advanced GPS Operations ............................... 127

Find Distance from Current Position ...................................... 127

Find Distance From Point to Point .......................................... 127

Icons........................................................................................... 127

Create Icon on Map............................................................... 128

iii

Create Icon at Current Position ........................................... 128

Delete an Icon ....................................................................... 128

Navigate to an Icon............................................................... 129

Routes........................................................................................ 129

Create and Save a Route ......................................................130

Delete a Route ....................................................................... 132

Edit a Route Name................................................................ 132

Edit Route Waypoints........................................................... 133

Navigate a Route................................................................... 133

Navigate a Route in Reverse ................................................ 134

Trails ......................................................................................... 135

Delete a Trail ........................................................................ 135

Edit a Trail Name ................................................................. 135

Edit a Trail Color .................................................................. 136

Edit a Trail Pattern .............................................................. 136

Utilities...................................................................................... 137

Alarm Clock........................................................................... 137

Sun/Moon Rise & Set Calculator.......................................... 137

Trip Calculator...................................................................... 137

Trip Down Timer................................................................... 137

Trip Up Timer ....................................................................... 137

Waypoints.................................................................................. 137

Delete a Waypoint................................................................. 137

Edit a Waypoint .................................................................... 138

Selecting a Waypoint ............................................................ 138

Set a Waypoint by Average Position .................................... 139

Set a Waypoint by Projecting a Position.............................. 139

Section 8: System & GPS Options ...................................... 141

Alarms ....................................................................................... 141

NMEA 2000 Alarm ................................................................... 142

Auto Satellite Search................................................................ 143

Check MMC Files and Storage Space...................................... 144

Communications Port Configuration ....................................... 144

Configure NMEA ...................................................................... 145

Coordinate System Selection.................................................... 145

Map Fix ..................................................................................... 147

Customize Page Displays ......................................................... 148

GPS Simulator .......................................................................... 149

Hide GPS Features ................................................................... 151

Initialize GPS............................................................................ 151

Map Auto Zoom......................................................................... 151

Map Data................................................................................... 151

Show Map Data..................................................................... 152

iv

Pop-up Map Information ...................................................... 152

Map Boundaries .................................................................... 152

Fill Water With White .......................................................... 152

Map Overlays (Range Rings; Lat/Long Grid) ...................... 152

Map Datum Selection ............................................................... 153

Map Detail Category Selection................................................. 154

Map Orientation ....................................................................... 154

NauticPath USA Marine Charts........................................... 156

Nautical Chart Notes............................................................ 156

Port Information ...................................................................157

Tidal Current Information ................................................... 158

Tide Information ................................................................... 160

Navionics



Charts..................................................................... 161

NMEA 2000............................................................................... 162

Overlay Data ............................................................................. 162

Pop-up Help............................................................................... 166

Reset Options ............................................................................ 166

Screen Contrast and Brightness .............................................. 167

Set Language ............................................................................ 167

Set Local Time .......................................................................... 168

Show WAAS Alarm................................................................... 168

Software Version Information.................................................. 169

Sounds and Alarm Sound Styles.............................................. 169

Track Smoothing....................................................................... 170

Trail Options ............................................................................. 170

General Trail Options ....................................................... 170

Specific Trail Options........................................................ 171

Delete Trail ........................................................................... 171

New Trail............................................................................... 171

Trail Visible/Invisible and Other Trail Options .................. 172

Transparency ............................................................................ 172

Units of Measure....................................................................... 173

Section 9: Searching .............................................................175

Find Streets............................................................................... 175

Find Any Item Selected by Map Cursor .................................. 176

Find Interstate Highway Exits ................................................ 177

Find Map Places or Points of Interest ..................................... 178

Find Streets or Intersections.................................................... 180

Find Waypoints......................................................................... 183

Section 10: Supplemental Material ...................................185

v

A CAREFUL NAVIGATOR NEVER RELIES ON ONLY ONE METHOD
TO OBTAIN POSITION INFORMATION.

WARNING!

When showing navigation data to a position (waypoint), a GPS unit will show
the shortest, most direct path to the waypoint. It provides navigation data to the
waypoint regardless of obstructions. Therefore, the prudent navigator will not
only take advantage of all available navigation tools when traveling to a way­point, but will also visually check to make sure a clear, safe path to the waypoint
is always available.

When a GPS unit is used in a vehicle, the vehicle operator is solely re­sponsible for operating the vehicle in a safe manner. Vehicle operators
must maintain full surveillance of all pertinent driving, boating or fly­ing conditions at all times. An accident or collision resulting in damage
to property, personal injury or death could occur if the operator of a
GPS-equipped vehicle fails to pay full attention to travel conditions and
vehicle operation while the vehicle is in motion.

CAUTION

WARNING!

vi

Section 1: Read Me First!

How this manual can get you out on the road, fast!

Welcome to the exciting world of digital sonar and GPS! We know
you're anxious to begin navigating and finding fish, but we have a favor
to ask. Before you grab the unit and begin installing it, please give us a
moment or two to explain how our manual can help you get the best
performance from your compact, wide-screen, combination fish finder
and mapping GPS receiver.

First, we want to thank you for buying a Lowrance sonar/GPS unit.
Whether you're a first time user or a professional fisherman, you'll dis­cover that your unit is easy to use, yet capable of handling demanding
navigation and sonar tasks. When you team your unit with our custom
mapping software MapCreate 6, you have an incredible combination.
You won't find another combination GPS and sonar unit with this much
power and this many features for this price!

Our goal for this book is to get you on the water fast, with a minimum
of fuss. Like you, we'd rather spend more time boating or fishing and
less time reading the manual!

So, we designed our book so that you don't have to read the whole thing
from front to back for the information you want. At the start (or end) of
each segment, we'll tell you what content is coming up next. If it's a
concept you're already familiar with, we'll show you how and where to
skip ahead for the next important topic. We've also made it easy to look
up any tips you may need from time to time.

The manual is organized into 10 sections. This first section is an intro­duction to the LMS-334 iGPS and LMS-339cDF iGPS sonar and GPS. It
tells you the basics you need to know before you can make the unit look
around and tell you where you are, or look below the surface to find
some fish.

Section 2 will help you install your unit and the transducer. We'll show
you how to get the MultiMedia Card (MMC) correctly installed inside
the unit. We'll also tell you about some of the available accessories.

Section 3 covers Basic Sonar Operation. It will show you how easy it is
to run your sonar, right out of the box. This section features a one-page
Sonar Quick Reference. (If you've already jumped ahead and fig-

ured out how to install the unit yourself, and you just can't wait
any longer, turn to the Quick Reference on page 49 and head
for the water!)

1

After you've gained some experience with your sonar, you'll want to
check out Section 4, which discusses more advanced Sonar Options and
Other Features.

When you come to a sonar menu command on your unit’s screen, you can
look it up in the manual by skimming over the table of contents, just flip­ping through Section 3 or scanning through the sonar options in Section 4.

If you're having difficulty with your sonar, you can find an answer to
the most common problems in Section 5, Sonar Troubleshooting.

The manual switches from sonar to navigation in Section 6, which in­troduces you to Basic GPS Operations. This section features a one-

page GPS Quick Reference on page 108.

Section 6 contains short, easy-to-scan GPS lessons that follow one an­other in chronological order. They're all you'll need to know to find your
way on the water quickly.

After you've learned the basics (or if you already have some GPS expe­rience), you may want to try out some of the unit’s many advanced
navigation features. That brings us to Section 7, Advanced GPS Opera-
tions. This section contains the rest of your unit’s GPS command func­tions, organized in alphabetical order.

When you come to a GPS menu command on the screen, look it up in
the manual by skimming the table of contents, flipping through Section
6 or scanning through the command portion of Section 7.

Your unit is ready to use right out of the box, but you can fine tune and
customize it's operation with dozens of options. Since sonar is the unit's
key feature, we put the main sonar options in Section 4. Some options,
such as screen brightness settings, affect both sonar and GPS opera­tions. We describe how to use those common options along with GPS
options in Section 8, System Setup and GPS Setup Options. Section 8 is
organized in alphabetical order.

In Section 9, we go into more detail on one of the unit’s most remarkable
GPS capabilities — Searching. We'll introduce a search example in the Ba­sic GPS Operation section, but there are so many map items you can
search for, we had to give this function it's own section in the manual! For
example, did you know your unit can look up business phone numbers,
functioning as a virtual Yellow Pages? We’ll show you how in Section 9.

Finally, in Section 10, we offer Supplemental Material, including a list
of the GPS datums used, warranties and customer service information.

Now, if you're into the fine details, glance over the next segment on
specifications to see just how much sonar and GPS power your unit con-

2

tains. It's important to us (and our power users), but, if you don't care
how many watts of power the unit has, or how many waypoints the your
unit can store, skip ahead to important information on how the sonar
works, on page 5. (Background on GPS begins on page 6.)

Capabilities and Specifications: LMS-334c iGPS and LMS-

339cDF iGPS

General

Display:............................ 5.0" (12.7 cm) diagonal; 256-color Solar-

MAX™ TFT display; programmable to
viewing preference.

Resolution:...................... 480 pixel x 480 pixel resolution; 230,400 total

pixels.

Backlighting:.................. Backlit fluorescent/ cold cathode screen and

keypad with multiple lighting levels for night
use.

Input power:................... 10 to 15 volts DC.

Current drain: ............... Sonar only: 500 ma lights off; 600 ma lights

on. With GPS and lights on: 700 ma.

Case size:......................... 5.4" H x 6.9" W x 3.4" D (13.8 x 17.6 x 8.6

cm); sealed and waterproof; suitable for
saltwater use.

MMC slots: ...................... One with waterproof door (SD card compati-

ble).

Recording:........................ GPS uses MMC & SD cards for recording trip

details and displaying charts or custom maps.
Sonar uses them to record and save sonar
chart logs.

Back-up memory: .......... Built-in memory stores sonar records and

GPS data for decades. User settings are
stored when unit is turned off.

Languages:...................... 10; menu languages selectable by user.

Sonar

Frequency:...................... LMS-339cDF: 50/200 kHz.

LMS-334c: 200 kHz.

Transducers: .................... A dual-frequency Skimmer



transducer with

built-in temperature sensor is packed with the

3

LMS-339cDF. A single-frequency Skimmer
transducer with built-in temperature sensor is
packed with the LMS-334c. Transducers offer
up to 60° of fish detection coverage and oper­ate at speeds up to 70 mph (61 kts).

Transmitter: ................... LMS-339cDF: 4,000 watts peak-to-peak/500

watts RMS. LMS-334c: 2,400 watts peak-to­peak/300 watts RMS.

Sonar sounding

Depth capability:........... LMS-339cDF: 2,500 feet/762 meters.

LMS-334c: 900 feet/274 meters.

(Actual capability depends on transducer
configuration and installation, bottom com­position and water conditions. All sonar
units typically read deeper in fresh water
than in salt water.)

Depth display:................ Continuous display.

Graph recording:........... Up to 2 GB on one MMC (or SD) card

Audible alarms: ............. Deep/shallow/fish/zone.

Automatic ranging:....... Yes, with instant screen updates.

Auto bottom track:........ Yes

Zoom bottom track: ...... Yes.

Split-screen zoom:......... Yes.

Surface water temp: ..... Yes, built into transducer.

Speed/distance log: ....... Yes, with optional speed sensor (sensor in-

cluded with LMS-339cDF.)

GPS

Receiver/antenna:............Internal; 12 parallel channel NMEA 2000-

ready GPS/WAAS antenna.

Background map:.......... Built-in custom, detailed Lowrance map.

Contains: enhanced detail of continental U.S.
and Hawaii. Includes more than 60,000 nav
aids and 10,000 wrecks/obstructions in
coastal and Great Lakes waters. Metro ar­eas, selected major streets/highways and in­terstate exit services details included.

4

Custom mapping: .......... MapCreate



6 software optional; optional

plug and play LEI FreedomMaps offer the
same high-detail without the computer work
of MapCreate. Other plug and play mapping
options include FreedomMaps, Fishing Hot



Spots
LakeMaster

Elite, LEI NauticPath charts,



ProMaps and Navionics



charts.

Mapping memory:............Up to 2 GB on one MMC (or SD) card.

Position updates: .......... Every second.

Position points: ............. 1,000 waypoints; 1,000 event marker icons.

Audible alarms: ............. Arrival/off-course/anchor.

Graphic symbols for
waypoints or event

marker icons: ................. 42.

Routes:............................. 100; up to 100 waypoints per route.

Plot Trails: ...................... 10 savable; up to 9,999 points per trail.

Zoom range:.................... 40 ranges; 0.02 to 4,000 miles.

NOTE:

The above memory capacities refer only the unit’s on-board memory.
The amount of GPS or sonar data you can record and save for recall
later is only limited by the number of MMC cards you have.

NOTICE!

The storage temperature range for your unit is from -4 degrees to +167
degrees Fahrenheit (-20 degrees to +75 degrees Celsius). Extended stor-

age in temperatures higher or lower than specified will damage the liq­uid crystal display in your unit. This type of damage is not covered by
the warranty. For more information, contact the factory's Customer

Service Department; phone numbers are listed on the last page.

How Lowrance Sonar Works

Sonar has been around since the 1940s, so if you already know how it
works, skip down to read about the relatively new technology of GPS.
But, if you've never owned a sonar fish finder, this segment will tell you
the under water basics.

Sonar is an abbreviation for SOund NA
nology developed during World War II for tracking enemy submarines.

vigation and Ranging, a tech-

5

(Lowrance developed the world's first transistorized sportfishing sonar
in 1957.) A sonar consists of a transmitter, transducer, receiver and
display. In simple terms, here's how it finds the bottom, or the fish:

The transmitter emits an electrical impulse, which the transducer con­verts into a sound wave and sends into the water. (The sound frequency
can't be heard by humans or fish.) The sound wave strikes an object
(fish, structure, bottom) and bounces back to the transducer, which
converts the sound back into an electrical signal.

The receiver amplifies this return signal, or echo, and sends it to the
display, where an image of the object appears on the scrolling sonar
chart. The sonar's microprocessor calculates the time lapse between the
transmitted signal and echo return to determine the distance to the
object. The whole process repeats itself several times each second.

Your unit can record a log of the sonar signals that scroll across the
screen and save them to the MMC memory card. (These recordings are
also called sonar charts or sonar graphs.) You can replay this sonar log
in the unit using the Sonar Simulator function, or play it back on a per­sonal computer using our free Sonar Viewer. The viewer is available for
download from the Lowrance web site, www.lowrance.com.

You can save several different sonar log files, erase 'em and record new
ones, over and over again. The size of your sonar recordings is only
limited by the free space available on your MMC.

How Lowrance GPS Works

You'll navigate faster and easier if you understand how your unit scans
the sky to tell you where you are on the earth — and, where you're go­ing. (But if you already have a working understanding of GPS receivers
and the GPS navigation system, skip ahead to Section 2, Installation &
Accessories on page 13. If you're new to GPS, read on, and you can later
impress your friends with your new-found knowledge.)

First, think of your unit as a small but powerful computer. (But don't
worry — we made the unit easy to use, so you don't need to be a com­puter expert to find your way!) It includes a keypad and a screen with
menus so you can tell it what to do. The screen also lets the unit show
your location on a moving map, as well as point the way to your desti­nation.

This gimbal-mounted unit uses an internal antenna and receiver,
which makes the whole system work something like your car radio. But
instead of your favorite dance tunes, this receiver tunes in to a couple of
dozen GPS satellites circling the earth. Your unit listens to signals from

6

as many satellites as it can "see" above the horizon, eliminates the
weakest signals, then computes its location in relation to those satel­lites. Once the unit figures its latitude and longitude, it plots that posi­tion on the moving map shown on the screen. The whole process takes
place several times a second!

The performance doesn't stop there. Stored in the permanent memory
of each unit is a basic background map of the entire world. We lock it in
here at the factory — you can't change or erase this map.

The background map is suitable for many navigation chores, but for
maximum accuracy and much more detail, you need our optional map­making software, MapCreate 6. Some unit features — such as
searching for businesses and addresses — won't work without a custom
MapCreate map. There is so much detail in our background map (and
even more in MapCreate) that we'll describe their contents and differ­ences in Section 6, Basic GPS Operations, on page 95.

Another portion of the unit’s onboard memory is devoted to recording
GPS navigation information, which includes waypoints, event marker
icons, trails and routes. This lets you look back the way you came.
Think of this data storage like the hard drive memory in a computer or
a tape in a cassette tape recorder. You can save several different GPS
data files, erase 'em and record new ones, over and over again. These
GPS Data Files (file format *.usr) can be shared between, not only the
LMS-334c iGPS and LMS-339cDF iGPS, but other Lowrance GPS units
and even personal computers.

Your unit has one more thing in common with a personal computer.
Just as computers have a floppy disk drive for storing and exchanging
files, the unit has a slot for an MMC (MultiMedia Card) or SD card (Se­cure Digital card) flash memory card. These solid-state memory devices
are about the size of a postage stamp, but can hold data ranging from 8
MB to 2 GB. (Compare that to a floppy disk's 1.44 MB capacity!) Your
unit uses all that MMC space for two key GPS purposes. (The MMC is
also used to record sonar logs.)

First, you can backup your onboard GPS Data Files by copying them to
the MMC. Since the MMC is MMCs, if you don't have a computer.) Our
MapCreate mapping software can save, edit or create its own GPS Data
Files, which can be copied to the MMC and then loaded from the MMC
into unit’s memory. (NOTE: No matter where they come from, GPS Data
Files must be loaded from the MMC into memory before your unit can
use them.)

The other key GPS use for MMCs is storage of special high-detail, cus­tom maps, which you can produce on your computer with our MapCre-

7

ate software. These MapCreate custom maps contain much greater de­tail than the basic background map. These Custom Map Files (file
format *.lcm) not only may be shared between the LMS-334c iGPS and
339cDF iGPS, but also with other Lowrance GPS and sonar/GPS units
as well as personal computers. (For example, the exact same MMC,
custom map files and GPS data files can be used interchangeably be­tween your gimbal-mounted unit and the hand-held iFINDER



GPS

receiver.)

Your unit automatically reads Custom removable (like a floppy disk or a
cassette tape), you can store these GPS Data Files on a personal com­puter equipped with an MMC card reader. (Or store them on a pocketful
of Map Files directly from the MMC or SD card. To use a custom map,
all you need to do is slide an MMC containing a map into the unit.

Introduction to GPS and WAAS

Well, now you know the basics of how your unit does its work. You
might be ready to jump ahead to Section 2, Installation & Accessories,
on page 13, so you can mount your unit and plug in the power. Or you
might want to see how our text formatting makes the manual tutorials
easy to skim. If that's the case, move on to "How to Use This Manual"
on page 11. But, if you want to understand the current state of satellite
navigation, look over this segment describing how GPS and its new
companion WAAS work together to get you where you're going.

The Global Positioning System (GPS) was launched July 17, 1995 by
the United States Department of Defense. It was designed as a 24­hour-a-day, 365-days-a-year, all weather global navigation system for
the armed forces of the U.S. and its allies. Civilian use was also avail­able at first, but it was less accurate because the military scrambled
the signal somewhat, using a process called Selective Availability (SA.)

GPS proved so useful for civilian navigation that the federal govern­ment discontinued SA on May 2, 2000, after the military developed
other methods to deny GPS service to enemy forces. Reliable accuracy
for civilian users jumped from 100 meters (330 feet) under SA to the
present level of 10 to 20 meters (about 30 to 60 feet.)

Twenty-four satellites orbit 10,900 nautical miles above the Earth,
passing overhead twice daily. A series of ground stations (with precisely
surveyed locations) controls the satellites and monitors their exact loca­tions in the sky. Each satellite broadcasts a low-power signal that iden­tifies the satellite and its position above the earth.

8

Three of these satellites are spares, unused until needed. The rest vir­tually guarantee that at least four satellites are in view nearly any­where on Earth at all times. The system requires signal reception from
three satellites in order to determine a position. This is called a 2D fix.
It takes four satellites to determine both position and elevation (your
height above sea level — also called altitude.) This is called a 3D fix.

A minimum of three satellites are required to determine a 2D fix.

Remember, the unit must have a clear view of the satellites in order to
receive their signals. Unlike radio or television signals, GPS works at
very high frequencies. These signals can be easily blocked by trees,
buildings, an automobile roof, even your body.

Like most GPS receivers, the unit doesn’t have a compass or any other
navigation aid built inside. It relies solely on the signals from the sat­ellites to calculate a position. Speed, direction of travel, and distance
are all calculated from position information. Therefore, in order it to
determine direction of travel, you must be moving and the faster, the
better. This is not to say that it won’t work at walking or trolling
speeds — it will. There will be more "wandering" of the data shown on
the display.

GPS alone is accurate for route navigation, but the U.S. Federal Avia­tion Administration has special aircraft navigation needs that go be­yond basic GPS. So, the FAA has developed a program to boost GPS
performance with its Wide Area Augmentation System, or WAAS. The
FAA commissioned the system on July 11, 2003.

WAAS is designed to increase GPS accuracy to within 7.6 meters verti­cally and horizontally, but it consistently delivers accuracies within 1-2
meters horizontal and 2-3 meters vertical, according to the FAA. It does

9

this by broadcasting correction signals on GPS frequencies. Your unit
automatically receives both GPS and WAAS signals.

However, there are some fringe areas of the U.S., including parts of
Alaska, that do not yet receive robust WAAS coverage. Continued
WAAS development is planned to extend WAAS coverage in the years
to come.

WAAS boosts the accuracy of land GPS navigation, but the system is
designed for aircraft. The satellites are in a fixed orbit around the
Equator, so they appear very low in the sky to someone on the ground
in North America. Aircraft and vessels on open water can get consis­tently good WAAS reception, but terrain, foliage or even large man­made structures can sometimes block the WAAS signal from ground
receivers.

You'll find that using your GPS receiver is both easy and amazingly
accurate. It’s easily the most accurate method of electronic navigation
available to the general public today. Remember, however, that this
receiver is only a tool. Always have another method of navigation avail­able, such as a map or chart and a compass.

Also remember that this unit will always show navigation information
in the shortest line from your present position to a waypoint, regardless
of terrain! It only calculates position, it can’t know what’s between you
and your destination, for example. It’s up to you to safely navigate
around obstacles, no matter how you’re using this product.

Free Training Aids Available

Now that you know something about the technology that makes this
unit possible, you are ready to start learning how to use that technol­ogy. This manual will guide you through the process of setting up and
running your unit, but that is only one of many resources available.

If you or a friend has Internet access, visit our web site. Find us at

WWW.LOWRANCE.COM. The site is packed with additional information

on using our products.

For instance, you can learn more about interpreting what you see on
your sonar screen with our free Sonar Tutorial. The tutorial includes
animated illustrations and more pictures of actual sonar returns, all
described in detail. There's even a printer friendly version of the tuto­rial available on our web. It makes a great supplement to this manual.

10

Sonar Viewer

You can also download a free copy of our Sonar Viewer software. This
PC-based software application plays back any sonar chart log recorded
with a Lowrance sonar product. Features include:

• Adjustable range, zoom, sensitivity, ColorLine, noise rejection,

surface clarity, etc.

• Color interpretation of sonar signals can be user defined.

• Operates like a Windows Multimedia Player with forward, re-

verse, pause, fast forward, fast reverse, and scroll buttons.

• Adjustments update the entire record displayed.

• Can print in full color.

• Window can dynamically be sized on your monitor.

• Mouse cursor shows GPS position, depth and sounding number

anywhere on the visible record.

Emulator

For the ultimate training aid, be sure to download the free emulator
software for your unit. This program can help you learn both basic and
advanced operations without burning boat fuel!

This PC application simulates the actual sonar/GPS unit on your com­puter. You can run it from your computer keyboard or use your mouse
to press the virtual keys. Easy download and installation instructions
are available on our web site.

The emulator works exactly like your real sonar/GPS unit. When using
the Sonar and GPS Simulators you can play back sonar logs, run GPS
routes and trails, even create real waypoints you can use in the field.
You can take snapshots of the Sonar Chart and print them or e-mail
them to friends.

And that is just some of the material available on our web site. To find
out what we have available, log on and look around. For now, we'll get
back to how to use this particular unit.

How to use this manual: typographical conventions

Many instructions are listed as numbered steps. The keypad and arrow
"keystrokes" appear as boldface type. So, if you're in a real hurry (or
just need a reminder), you can skim the instructions and pick out what
menu command to use by finding the boldface command text. The fol­lowing paragraphs explain how to interpret the text formatting for
those commands and other instructions:

11

Arrow Keys

The arrow keys control the movement of dotted cross-hair lines on your
mapping screen called the cursor. The arrow keys also control a hori­zontal line depth cursor on the sonar screen. The arrow keys help you
move around the menus so you can execute different commands. They
are represented by symbols like these, which denote the down arrow

key, the up arrow, the left arrow and the right arrow: ↓ ↑, ← →.

Keyboard

The other keys perform a variety of functions. When the text refers to a
key to press, the key is shown in bold, sans serif type. For example, the
"Enter/Icons" key is shown as

ENT and the "Menu" key is shown as MENU.

Menu Commands

A menu command or a menu option will appear in small capital letters,
in a bold sans serif type like this:

ROUTE PLANNING. These indicate that

you are to select this command or option from a menu or take an action
of some kind with the menu item. Text that you may need to enter or file
names you need to select are show in italic type, such as trail name.

Instructions = Menu Sequences

Most functions you perform with your unit are described as a sequence
of key strokes and selecting menu commands. We've written them in a
condensed manner for quick and easy reading.

For example, instructions for navigating a trail would look like this:

1. From the Map Page, press

2. Press ↓ to Trail 1|

ENT|→|↓ to NAVIGATE|ENT.

MENU|MENU|↓ to MY TRAILS|ENT.

3. You are asked to wait while it converts the trail into a route.

4. The wait message disappears and the unit begins showing
navigation information along the trail..

Translated into complete English, step 1 above would mean: "Start on
the Map Page. Press the Menu key twice. Next, repeatedly press (or
press and hold) the down arrow key to scroll down the menu and select
(highlight) the My Trails menu command. Finally, press the Enter
key."

Step 2 would mean: "Press the down arrow key repeatedly to scroll to
the trail named Trail 1, and press Enter. Next, press the right arrow
key and then the down arrow key to highlight the Navigate command,
then press Enter."

12

Section 2: Installation

Preparations

You can install the unit in some other order if you prefer, but we rec­ommend this installation sequence:

Caution:

You should read over this entire installation section before drill­ing any holes in your vessel!

1. Determine the approximate location for the unit, so you can plan how
and where to route the cables for the transducer, any sensor and power.
This will help you make sure you have enough cable length for the de­sired configuration.

NOTE:

The GPS antenna is inside the unit, so you must mount the unit in
a location with an unobstructed view of the sky.

2. Determine the approximate location for the transducer, any sensor
and their cable routes.

3. Determine the location of your battery or other power connection,
along with the power cable route.

4. Install the transducer and route the transducer cable to the sonar
unit. Install the speed or temp sensor, if applicable, and route the cable
to the unit.

5. Route the power cable from the unit's location to an appropriate
power source and connect it there.

6. Connect the transducer/power cable (and any sensor cables) to the
unit and mount the unit on the bracket.

Transducer Installation



These instructions will help you install your Skimmer
transom, on a trolling motor or inside a hull. These instructions cover
both single- and dual-frequency Skimmer transducers. Please read all
instructions before proceeding with any installation.

The smaller single-frequency Skimmers typically use a one-piece,
stainless steel mounting bracket. The larger dual-frequency Skimmers
typically use a two-piece, plastic mounting bracket. The optional troll­ing motor mount uses a one-piece plastic bracket with an adjustable
strap.

These are all "kick-up" mounting brackets. They help prevent damage if
the transducer strikes an object while the boat is moving. If the trans-

13

transducer on a

ducer does "kick-up," the bracket can easily be pushed back into place
without tools.

Read these instructions carefully before attempting the installation.
Determine which of the installation methods is right for your boat. Use
extreme care if mounting the transducer inside the hull, because once
the epoxy is applied and it is set into position, the transducer cannot be
removed. Remember, transducer location is the most critical part

of a sonar installation.

Recommended Tools and Supplies

If you prefer the option of routing the cable through the transom, you
will need a 1" (25.4 mm) drill bit. A transom mount requires use of a
high quality, marine grade above- or below-waterline sealant/adhesive
compound.

NOTE:

The following installation types also call for these recommended
tools and required supplies (supplies are not included):

Single-frequency transom installations

Tools include: two adjustable wrenches, drill, #29 (0.136") drill bit, flat­head screwdriver. Supplies: high quality, marine grade above- or below­waterline sealant/adhesive compound.

Dual-frequency transom installations

Tools: two adjustable wrenches, drill, #20 (0.161") drill bit, flat-head
screwdriver. Supplies: four, 1" long, #12 stainless steel slotted wood
screws, high quality, marine grade above- or below-waterline seal-
ant/adhesive compound.

Single-frequency trolling motor installations

Tools: two adjustable wrenches, flat-head screwdriver. Supplies: plastic
cable ties.

Shoot-through hull installations

Tools: these will vary depending on your hull's composition. Consult
your boat dealer or manufacturer. Other tools are a wooden craft stick
or similar tool for stirring and applying epoxy, and a paper plate or
piece of cardboard to mix the epoxy on. Supplies: rubbing alcohol, 100
grit sandpaper, specially formulated epoxy adhesive available from LEI
(see ordering information on the inside back cover). A sandwich hull
also requires polyester resin.

Selecting a Transducer Location

1. The location must be in the water at all times, at all operating speeds.

2. The transducer must be placed in a location that has a smooth flow of
water at all times. If the transducer is not placed in a smooth flow of

14

water, interference caused by bubbles and turbulence will show on the

prevent the transducer from

location

Deadrise less than 10

sonar's display in the form of random lines or dots whenever the boat is
moving.

NOTE:

Some aluminum boats with strakes or ribs on the outside of the
hull create large amounts of turbulence at high speed. These boats
typically have large outboard motors capable of propelling the boat
at speeds faster than 35 mph. Typically, a good transom location on
aluminum boats is between the ribs closest to the engine.

3. The transducer should be installed with its face pointing straight
down, if possible. For shoot-thru applications: Many popular fishing
boat hulls have a flat keel pad that offers a good mounting surface. On
vee hulls, try to place the transducer where the deadrise is 10° or less.

°

Pad

Vee pad hull (left); Vee hull (right). A pod style transducer is shown

here, but the principle is the same for Skimmers inside a hull.

Strakes

4. If the transducer is mounted on the transom, make sure it doesn't
interfere with the trailer or hauling of the boat. Also, don't mount it
closer than approximately one foot from the engine's lower unit. This
will prevent cavitation (bubble) interference with propeller operation.

5. If possible, route the transducer cable away from other wiring on the
boat. Electrical noise from engine wiring, bilge pumps and aerators can
be displayed on the sonar's screen. Use caution when routing the trans­ducer cable around these wires.

CAUTION: Clamp the trans­ducer cable to transom near
the transducer. This will help

entering the boat if it is
knocked off at high speed.

Poor location

Good

Good location

Poor angle

Good and poor transducer locations.

Good location

15

Transom

Transom

Transducer

centerline

Hull bottom

Align transducer centerline with hull bottom. A dual frequency

transducer (left) and a single frequency transducer (right).

Hull bottom

How low should you go?

For most situations, you should install your Skimmer transducer so
that its centerline is level with the bottom of the boat hull. This will
usually give you the best combination of smooth water flow and protec­tion from bangs and bumps.

However, there are times when you may need to adjust the transducer
slightly higher or lower. (The slots in the mounting brackets allow you
to loosen the screws and slide the transducer up or down.) If you fre­quently lose bottom signal lock while running at high speed, the trans­ducer may be coming out of the water as you cross waves or wakes.
Move the transducer a little lower to help prevent this.

If you cruise or fish around lots of structure and cover, your transducer
may be frequently kicking up from object strikes. If you want, you may
move the transducer a little higher for more protection.

There are two extremes you should avoid. Never let the edge of the
mounting bracket extend below the bottom of the hull. Never let the
bottom – the face – of the transducer rise above the bottom of the hull.

Shoot-Thru-Hull vs. Transom Mounting

In a shoot-thru-hull installation, the transducer is bonded to the inside
of the hull with epoxy. The sonar "ping" signal passes through the hull
and into the water. This differs from a bolt-thru-hull installation (often
called "thru-hull"). In that case, a hole is cut in the hull and a specially
designed transducer is mounted through the hull with a threaded shaft
and nut. This puts the transducer in contact with the water.

Typically, shoot-thru-hull installations give excellent high speed opera­tion and good to excellent depth capability. There is no possibility of
transducer damage from floating objects, as there is with a transom­mounted transducer. A transducer mounted inside the hull can't be

16

knocked off when docking or loading on a trailer.

The shoot-thru-hull installation does have its drawbacks. First, some
loss of sensitivity does occur, even on the best hulls. This varies from
hull to hull, even from different installations on the same hull. This is
caused by differences in hull lay-up and construction.

Second, the transducer angle cannot be adjusted for the best fish arches
on your sonar display. (This is not an issue for flasher-style sonars.)
Lack of angle adjustment can be particularly troublesome on hulls that
sit with the bow high when at rest or at slow trolling speeds.

Third, a transducer CAN NOT shoot through wood and metal hulls.
Those hulls require either a transom mount or a thru-hull installation.

Fourth, if your Skimmer transducer has a built in temp sensor, it will
only show the temperature of the bilge, not the water surface temp.

Follow the testing procedures listed in the shoot-thru-hull installation
section of this instruction booklet to determine if you can satisfactorily
shoot through the hull.

Transom Transducer Assembly and Mounting

The best way to install these transducers is to loosely assemble all of
the parts first, place the transducer's bracket against the transom and
see if you can move the transducer so that it's parallel with the ground.

The following instructions sometimes vary depending on the mounting
bracket that came with your transducer. Single frequency Skimmers
come with a one-piece stainless steel bracket, while dual frequency
Skimmers come with a two-piece plastic mounting bracket. Use the set
of instructions that fits your model.

1. Assembling the bracket.

A. One-piece bracket: Press the two small plastic ratchets into the

sides of the metal bracket as shown in the following illustration. Notice
there are letters molded into each ratchet. Place each ratchet into the
bracket with the letter "A" aligned with the dot stamped into the metal
bracket. This position sets the transducer's coarse angle adjustment for a
14° transom. Most outboard and stern-drive transoms have a 14° angle.

17

Dot

Align plastic ratchets in bracket.

B. Two-piece bracket: Locate the four plastic ratchets in the trans­ducer's hardware package. Press two ratchets into the sides of the
plastic bracket and two on either side of the transducer as shown in
the following illustrations. Notice there are letters molded into each
ratchet.

Place the ratchets into the bracket with the letter "A" aligned with the
alignment mark molded into the bracket. Place the ratchets onto the
transducer with the letter "A" aligned with the 12 o'clock position on
the transducer stem. These positions set the transducer's coarse angle
adjustment for a 14° transom. Most outboard and stern-drive tran­soms have a 14° angle.

Alignment letters

Alignment

positions

Transducer

bracket

Transducer bracket

Transducer

Insert and align ratchets.

Transducer

Ratchet

Add ratchets to bracket and transducer.

Ratchet

18

2. Aligning the transducer on the transom.

Flat washer

A. One-piece bracket: Slide the transducer between the two ratch­ets. Temporarily slide the bolt though the transducer assembly and
hold it against the transom. Looking at the transducer from the side,
check to see if it will adjust so that its face is parallel to the ground.
If it does, then the "A" position is correct for your hull.

If the transducer's face isn't parallel with the ground, remove the
transducer and ratchets from the bracket. Place the ratchets into the
holes in the bracket with the letter "B" aligned with the dot stamped
in the bracket.

Reassemble the transducer and bracket and place them against the
transom. Again, check to see if you can move the transducer so it's
parallel with the ground. If you can, then go to step 3A. If it doesn't,
repeat step 2A, but use a different alignment letter until you can
place the transducer on the transom correctly.

Ratchets

B. Two-piece bracket: Assemble the transducer and bracket as
shown in the following figure. Temporarily slide the bolt though the
transducer assembly but don't tighten the nut at this time. Hold the
assembled transducer and bracket against the transom. Looking at the
transducer from the side, check to see if it will adjust so that its face is
parallel to the ground. If it does, then the "A" positions are correct for
your hull.

Insert bolt and check transducer position on transom.

Bolt

Flat washer

Assemble transducer and bracket.

Lock washer

Nut

19

If the transducer's face isn't parallel with the ground, remove and
disassemble the transducer and ratchets. Place the ratchets into the
bracket holes with the letter "B" aligned with the bracket alignment
mark. Place them on the transducer aligned with the 12 o'clock posi­tion on the transducer stem.

Reassemble the transducer and bracket and place them against the
transom. Again, check to see if you can move the transducer so it's
parallel with the ground. If you can, then go to step 3B. If it doesn't,
repeat step 2B, but use a different alignment letter until you can
place the transducer on the transom correctly.

3. Assembling the transducer.
A. One-piece bracket: Once you determine the correct position for

the ratchets, assemble the transducer as shown in the following fig­ure. Don't tighten the lock nut at this time.

Metal

Nut

washer

Rubber
washers

Assemble transducer and bracket.

Metal washer

Bolt

B. Two-piece bracket: Once you determine the correct position for
the ratchets, assemble the transducer as shown in the figure in step
2B. Don't tighten the lock nut at this time.

4. Drilling mounting holes.

Hold the transducer and bracket assembly against the transom. The
transducer should be roughly parallel to the ground. The trans­ducer's centerline should be in line with the bottom of the hull. Don't
let the bracket extend below the hull!

Mark the center of each slot for the mounting screw pilot holes. You
will drill one hole in the center of each slot.

Drill the holes. For the one-piece bracket, use the #29 bit (for the #10
screws). For the two-piece bracket, use the #20 bit (for the #12
screws).

20

Transom

Flat-bottom hull

Transom

Position transducer mount on transom and mark mounting holes.

Side view shown (left) and seen from above (right).

5. Attaching transducer to transom.
A. One-piece bracket: Remove the transducer from the bracket and

re-assemble it with the cable passing through the bracket over the
bolt as shown in the following figures.

For single-frequency Skimmer, route cable over bolt and through

bracket. Side view shown (left) and seen from above (right).

Both bracket types: Attach the transducer to the transom. Slide the
transducer up or down until it's aligned properly with the bottom of
the hull as shown in the preceding and following figures. Tighten the
bracket's mounting screws, sealing them with the sealant compound.

Adjust the transducer so that it's parallel to the ground and tighten
the nut until it touches the outer washer, then add 1/4 turn. Don't
over tighten the lock nut! If you do, the transducer won't "kick-up" if
it strikes an object in the water.

Bottom

of

hull

Deep-"vee" hull

Align transducer centerline with hull bottom and attach transducer to

transom. Rear view of dual-frequency Skimmer shown.

21

6. Route the transducer cable through or over the transom to the so-

Flat washer

nar unit. Make sure to leave some slack in the cable at the transducer. If
possible, route the transducer cable away from other wiring on the boat.
Electrical noise from the engine's wiring, bilge pumps, VHF radio wires
and cables, and aerators can be picked up by the sonar. Use caution
when routing the transducer cable around these wires.

WARNING:

Clamp the transducer cable to the transom close to the
transducer. This can prevent the transducer from enter­ing the boat if it is knocked off at high speed.

If you need to drill a hole in the transom to pass the connector through,
the required hole size will be 5/8".

Caution:

If you drill a hole in the transom for the cable, make sure it is lo­cated above the waterline. After installation, be sure to seal the
hole with the same marine grade above- or below-waterline seal­ant used for the mounting screws.

7. Make a test run to determine the results. If the bottom is lost at

high speed, or if noise appears on the display, try sliding the transducer
bracket down. This puts the transducer deeper into the water, hope­fully below the turbulence causing the noise. Don't allow the transducer
bracket to go below the bottom of the hull!

Trolling Motor Bracket Installation
(single-frequency only)

1. Attach the optional TMB-S bracket to the transducer as shown in the
following figure, using the hardware supplied with the transducer.
(Note: The internal tooth washer is supplied with the TMB-S.)

Bolt

Attach motor mounting bracket to transducer.

Internal tooth washer

Nut

2. Slide the adjustable strap supplied with the TMB-S through the slot
in the transducer bracket and wrap it around the trolling motor. Po­sition the transducer to aim straight down when the motor is in the
water. Tighten the strap securely.

22

TMB-S bracket

3. Route the transducer cable alongside the trolling motor shaft. Use
plastic ties (not included) to attach the transducer cable to the troll­ing motor shaft. Make sure there is enough slack in the cable for the
motor to turn freely. Route the cable to the sonar unit and the trans­ducer is ready for use.

Transducer mounted on trolling motor, side view.

Transducer Orientation and Fish Arches

If you do not get good fish arches on your display, it could be because
the transducer is not parallel with the ground when the boat is at rest
in the water or at slow trolling speeds. If the arch slopes up – but not
back down – then the front of the transducer is too high and needs to be
lowered. If only the back half of the arch is printed, then the nose of the
transducer is angled too far down and needs to be raised.

Transducer aimed

too far back

Full fish arch

Transducer angles and their effects on fish arches.

Partial fish arches

Proper transducer angle

23

Transducer aimed

too far forward

NOTE:

Periodically wash the transducer's face with soap and water to re­move any oil film. Oil and dirt on the face will reduce the sensitivity
or may even prevent operation.

Shoot-Thru-Hull Preparation

Hulls With Flotation Materials

The transducer installation inside a fiberglass hull must be in an area
that does not have air bubbles in the resin or separated fiberglass lay­ers. The sonar signal must pass through solid fiberglass. A successful
transducer installation can be made on hulls with flotation materials
(such as plywood, balsa wood or foam) between layers of fiberglass if
the material is removed from the chosen area. See the figure below.

WARNING:

Do not remove any material from your inner hull unless
you know the hull's composition. Careless grinding or
cutting on your hull can result in damage that could sink
your boat. Contact your boat dealer or manufacturer to
confirm your hull specifications.

Fill with resin

Fill with resin

Flotation material

Inner hull

Epoxy to hull first

Epoxy the transducer to a solid portion of the hull.

Outer hull

For example, some (but not all) manufacturers use a layer of fiberglass,
then a core of balsa wood, finishing with an outer layer of fiberglass.
Removing the inner layer of fiberglass and the balsa wood core exposes
the outer layer of fiberglass. The transducer can then be epoxied directly
to the outer layer of fiberglass. After the epoxy cures for 24 hours, fill the
remaining space with polyester resin. When the job is finished, the hull
is watertight and structurally sound. Remember, the sonar signal must
pass through solid fiberglass. Any air bubbles in the fiberglass or the
epoxy will reduce or eliminate the sonar signals.

Testing Determines Best Location

Ideally, the shoot-thru transducer should be installed as close to the
transom as possible, close to the centerline. This will give you the best
performance during high speed maneuvers.

24

Transducer location

Second bottom

True bottom

(high speed)

Shoot-thru-hull transducer locations for

high speed or trolling speed operation.

Transducer location

(trolling speed)

To choose the proper location for shoot-thru-hull mounting, follow these
testing procedures: (You may need a helper to complete these steps.)

1. Anchor the boat in about 30 feet of water. Add a little water to the
sump of the boat. Plug the transducer into the sonar unit, turn it on,
then hold the transducer over the side of the boat in the water. Adjust
the sensitivity and range controls until a second bottom echo is seen on
the display. (You'll need to turn off Auto Sensitivity, Auto Depth Range
and ASP. Try a range setting that is two to three times the water
depth. The harder (more rocky) the bottom, the easier it will be to get a
second bottom signal.) Don't touch the controls once they've been set.

Manual range setting

Example of a second bottom signal. Unit is in 30 feet of water with

range set at 80 feet and sensitivity set at 87 percent.

2. Next, take the transducer out of the water and place it in the water
in the sump of the boat, face down. Notice how the signal strength
decreases. The second bottom signal will probably disappear and the
bottom signal intensity will likely decrease.

25

3. Now move the transducer around to find the best location with the
strongest possible bottom signal. If you find a spot with an acceptable
bottom signal, mark the location and move on to step 4.

If you can't get an acceptable bottom signal, try turning up the sensi­tivity by three or five keystrokes and then move the transducer around
once more. If you find a spot that works, mark it and move on to step 4.

If you have to turn up sensitivity by more than five keystrokes to get
a good signal, the transducer should be mounted on the outside of the
hull. This is especially true if you have to turn sensitivity all the way
up to get a decent bottom signal.

4. Most people can get good results by following steps 1 through 3, so this
step is optional. If you want to make an extra effort to be absolutely sure
that your selected location will work under all conditions, make a test
run with the boat on plane and observe the bottom signal.

You'll need to figure some way to prop the transducer into position while
you make your test run. (A brick or two might be sufficient to hold it in
place.)

5. When you're satisfied with a location, mark it and proceed with the
installation.

Shoot-Thru-Hull Installation

If you are installing the transducer on a hull with floatation material
sandwiched within the hull, refer to the text "Hulls With Flotation Ma­terials" beginning on page 24.

1. Make sure the area is clean, dry and free of oil or grease, then sand
both the inside surface of the hull and the face of the transducer with
100 grit sandpaper. The sanded hull area should be about 1-1/2 times
the diameter of the transducer. The surface of the hull must be flat
so the entire transducer face is in contact with the hull prior to
bonding. After sanding, clean the hull and transducer with rubbing
alcohol to remove any sanding debris.

26

Spread epoxy here

the bow of the boat.

Sand this surface
(unit's face)

Orient the Skimmer
with the nose facing

To bow

Epoxy transducer to hull.

WARNING:

Use only the epoxy available from LEI. It has been for-
mulated to work with these installation procedures.
Other epoxy types may be too thin or may not cure to the
right consistency for optimum transducer performance.

2. The epoxy consists of the epoxy itself and a hardener. Remove the
two compounds from the package and place them on the paper plate.
Thoroughly stir the two compounds together until the mixture has a
uniform color and consistency. Do not mix too fast or bubbles will
form in the epoxy. After mixing, you have 20 minutes to complete the
installation before the epoxy becomes unworkable.

Spread a thin layer of epoxy (about 1/16" or 1.5 mm thick) on the face
of the transducer as shown in the previous figure. Make sure there
are no air pockets in the epoxy layer! Then, apply the remaining ep­oxy to the sanded area on the hull.

3. Press the transducer into the epoxy, twisting and turning it to force
any air bubbles out from under the transducer face. Stop pressing
when you bottom out on the hull. When you're finished, the face of
the transducer should be parallel with the hull, with a minimum
amount of epoxy between the hull and transducer.

4. Apply a weight, such as a brick, to hold the transducer in place while
the epoxy cures. Be careful not to bump the transducer while the ep­oxy is wet. Leave the weight in place for a minimum of three hours.
Allow the epoxy to cure for 24 hours before moving the boat.

5. After the epoxy has cured, route the cable to the sonar unit and it's
ready to use.

27

Speed/Temperature Sensors

Optional Speed Sensor Installation

All the units in this series can display speed and distance traveled, but
only the LMS-339cDF iGPS comes packed with a speed sensor. If you
want to purchase an optional additional sensor for your unit, refer to
the accessory ordering information inside the back cover of this man­ual. The following instructions describe how to install the speed sensor.

Recommended tools for this job include: drill, 7/8" drill bit, 1/8" drill bit
for pilot holes, screwdriver. Required supplies for this job include: four
#8 stainless steel wood screws (3/4" long), high quality, marine grade
above- or below-waterline sealant.

First find a location on the boat's transom where the water flow is
smoothest. Don't mount the sensor behind strakes or ribs. These will
disturb the water flow to the speed sensor. Make sure the sensor will
remain in the water when the boat is on plane. Also make sure the lo­cation doesn't interfere with the boat's trailer. Typically, the sensor is
mounted about one foot to the side of the transom's centerline.

Once you've determined the proper location for the unit, place the sen­sor on the transom. The bottom of the bracket should be flush with the
hull's bottom. Using the sensor as a template, mark the hull for the
screws' pilot holes. Drill four 1/8" holes, one in each end of the slots.

Mount the sensor to the hull using #8 stainless steel wood screws (not
included). Use a high quality, marine grade above- or below-waterline
sealant to seal the screws. Make sure the sensor is flush with the bot­tom of the hull and tighten the screws.

Good location

Stern view showing good location for mounting sensor on transom.

28

Transom

Bottom of hull

Speed sensor mounting configuration:

side view (left) and rear view (right.)

Bottom of hull

If the base of the transom has a radius, fill the gap between the tran­som and the sensor with the sealant compound. This will help ensure a
smooth water flow.

Route the sensor's cable through or over the transom to the sonar unit.
If you need to drill a hole in the transom to pass the connector through,
the required hole size is 7/8".

CAUTION:

If you drill a hole in the transom for the cable, make sure it is lo­cated above the waterline. After installation, be sure to seal the
hole with the same marine grade above- or below-waterline seal­ant used for the screws.

The sensor is now ready for use. Connect the sensor to the sonar socket
on the back of your unit and connect the transducer to the speed sen­sor's socket. If you have any questions concerning the installation of the
sensor, please contact your local boat dealer.

Power Connections

Your unit comes with a power/data cable that splits into three ends,
each with several exposed wires (shown in the following figure). The
end with 4 wires (blue, yellow, orange and shield) is a Data cable that
connects to a NMEA 0183 interface. The end with three wires (red,
black and shield) is a power cable that connects to a NMEA 2000
(For more detailed information on NMEA 2000 or LowranceNET
networks, see the NMEA 2000 Networks General Information booklet
packed with your unit.) The thicker three-wire cable (red, black and
white) is the Power Supply for your unit (and optional external speaker
connection for some units).

Depending on your configuration, you may not use all of the wires. The
following segments include instructions for installing all the unit's
wires.



buss.

29

Power Supply wires:
red, black and white

To unit

NMEA 2000 Power wires:

red, black and shield

Data Cable wires: blue,
yellow, orange and shield

The Power/Data cable for this unit.

Caution

All of the wires in the power/data cable have bare ends for eas­ier installation. The bare ends on any unused wires could cause
an electrical short if left exposed. To prevent this, you should
cover the individual wire ends – either by capping them with
wire nuts or wrapping them with electrical tape. (You should cut
off the bare wire before taping off the ends.)

Powering a NMEA 2000 Buss

(NMEA 2000 Power cable)

A NMEA 2000 buss must be connected to a 12-volt DC power source to
operate. If you have a pre-existing NMEA 2000 installation, it may al­ready be connected to another power source. If your NMEA 2000 buss is
already powered, you can ignore the NMEA 2000 Power cable. Never

attach two power sources to a single NMEA 2000 buss.

If you need to power a NMEA 2000 buss, attach the NMEA 2000 Power
cable to an accessory power switch. The cable's red wire should be at­tached (with the provided 3-amp fuse) to the positive terminal and the
cable's black and shield wires should both be attached to the negative
terminal.

You can attach the NMEA 2000 power cable directly to the boat's bat­tery, but you must use the fuse and install an on-off switch so
you can shut off power to the network. If a NMEA 2000 power ca­ble is connected directly to a battery, the NMEA 2000 network will con­tinuously draw power and drain the battery, even though the boat, your
unit and other NMEA 2000 devices are turned off.

Caution:

Never connect a NMEA 2000 power cable to an un-switched
power supply. Failure to use a power switch will allow the
NMEA 2000 network to drain the boat's battery when the system
is not in use! When you are not using the network, you should al­ways shut the power off.

30

Powering the Unit
(Power Supply cable – red and black wires)

The unit works from a 12-volt battery system. For the best results, at­tach the unit power cable directly to the battery. You can attach the
power cable to an accessory or power buss, but you may have problems
with electrical interference. Therefore, it's safer to go ahead and attach
the power cable directly to the battery.

CAUTION:

When using the unit in a saltwater environment, we strongly rec­ommend that you shut off the power supply to the unit power cable
when the unit is not in use. When the unit is turned off but still
connected to a power supply, electrolysis can occur in the power ca­ble plug. This may result in corrosion of the plug body along with
the electrical contacts in the cable and the unit's power socket.

In saltwater environments we recommend you connect the unit
power cable to the auxiliary power switch included in most boat
designs. If that results in electrical interference, or if such a
switch is not available, we recommend connecting direct to the
battery and installing an inline switch. This will let you shut off
power to the power cable when the unit is not in use. When you
are not using the unit, you should always shut off power to the
power cable, especially when the power cable is disconnected from
the unit.

If possible, keep the power cable away from other boat wiring, especially
the engine's wires. This will provide the best isolation from electrical
noise. If the cable is not long enough, splice #18 gauge wire onto it.

The power cable has two wires, red and black. Red is the positive lead,
black is negative or ground. (There is also a white wire to power an op­tional external speaker for some units.) Make sure to attach the in-line
fuse holder to the red lead as close to the power source as possible.

For example, if you have to extend the power cable to the battery or
power buss, attach one end of the fuse holder directly to the battery or
power buss. This will protect both the unit and the power cable in the
event of a short. It uses a 3-amp fuse.

31

To power a
NMEA 2000
buss, also
connect NMEA
2000 Power
cable to a
switched
power source.

To unit

Mandatory
network
power-off
switch

External speaker wire
(not used by this unit)

Black wire

Optional power-off
switch for salt­water installations

Red wire with

3 amp fuse

12 volt

battery

Data Cable

Power connections for LMS-334c iGPS and LMS-339cDF iGPS units.

NMEA 2000 Power Cable

NOTE:

If you are powering a NMEA 2000 buss, you will attach both the
NMEA 2000 Power cable and the unit's Power Supply cable to an
electric power source.

WARNING:

This product must be independently fused with the en­closed 3-amp fuse (or equivalent), even if you connect to
a fused accessory or power buss.

If a malfunction happens inside the unit, extensive dam­age can occur if the enclosed fuse is not used. As with all
electrical devices, this unit could be damaged to a point
that it is unrepairable and could even cause harm to the
user when not properly fused.

CAUTION:

Do not use this product without a 3-amp fuse wired into the power
cables! Failure to use a 3-amp fuse will void your warranty.

This unit has reverse polarity protection. No damage will occur if the
power wires are reversed. However, the unit will not work until the
wires are attached correctly.

GPS Internal Antenna

The unit has a built-in 12-parallel channel GPS + WAAS antenna.

NMEA 2000 Cable Connections

NMEA 2000 is a new buss network specifically designed for boats. This is
a very young industry standard and, at the time of printing, few boats
being built now have a NMEA 2000 buss installed. Over the next few

32

years, however, NMEA 2000 will become much more common. To help
you get the most out of this technology, your Lowrance unit is designed
to work with a NMEA 2000 network. You can install a network yourself
using LowranceNET components and devices.

To NMEA 2000
network port

Lowrance unit direct connection to NMEA 2000 buss.

To unit's
Network
socket

Connecting to a NMEA 2000 Network

Your unit can be connected to a NMEA 2000 buss, receiving sensor infor­mation from any Lowrance units attached to the buss. Contact LEI Extras
(look inside back cover for accessory ordering information) for a NMEA
2000 buss adapter cable if you would like to do this. You can connect the
unit directly to a network port. To do so, attach the adapter cable's manual
locking collar connector to the Network port on the back of the sonar unit
and attach the other end to an available port on the NMEA 2000 buss. As
soon as the unit is connected to the network, it will begin receiving
shared information. Please note the buss must be powered to operate.
(See instructions in this section on powering a NMEA 2000 buss.)

IMPORTANT NOTE:

The data from your internal GPS receiver will not be trans­mitted across the LowranceNET NMEA 2000 network. You
must have an LGC-2000 GPS antenna module in the network
for that to happen. Installation instructions for the LGC­2000 and other electronic probe sensors, like the EP-10 Fuel
Flow and EP-15 Fluid Level sensor are available in the
document "Instructions for Using LowranceNET



NMEA



2000 Devices with LMS-334, LMS-339 and GlobalMap 3600."
If the document is missing, contact customer service or down­load it free at www.lowrance.com.

NMEA 0183 Wiring
(Data cable)

To exchange NMEA 0183 data, this unit has one NMEA 0183 version

2.0 communication port. Com port one (Com-1) can be used to receive

NMEA 0183 format GPS data. The com port can also transmit NMEA
0183 format GPS data to another device.

The four wires for the com port are combined with the Power Supply
cable and NMEA 2000 Power cable to form the power/data cable (shown
earlier). Com-1 uses the yellow wire to transmit, the orange wire to re­ceive and the shield wire for signal ground. Your unit does not use the
blue wire.

33

Yellow (Transmit)

Orange (Receive)

Com-1
To unit

Com-1 wiring to receive NMEA position information

Com-1
To unit

Com-1 wiring to transmit NMEA position information

Shield (Ground)

from some other GPS receiver.

Shield (Ground)

to another NMEA-compatible device.

NMEA Transmit

Ground

NMEA Receive

Ground

To Other

GPS Receiver

To Other

Device

34

Sonar socket

Optional speed sensor

Transducer

Network
socket

NMEA 2000

Power cable

Power/Data socket

NMEA 0183

Data cable

(four wires)

Power Supply

cable

LMS-334c iGPS and LMS-339cDF iGPS cable connections.

Mounting the Unit: Bracket or Portable

You can install the sonar unit on the top of a dash with the supplied
gimbal bracket. It can also be mounted on a portable power supply.

If you use the supplied bracket, you may be interested in the optional
R-A-M
bracket to a swivel mount.



bracket mounting system. This converts the unit's gimbal

35

Optional R-A-M mounting system.

Bracket Installation

Mount the unit in a convenient location, provided there is clearance
behind the unit when it's tilted for the best viewing angle. This must

be a location with a clear view of the sky, so the internal GPS
antenna can lock-on to satellite signals. Make sure there is enough

room behind the unit to attach the power and transducer cables.

Holes in the bracket's base allow wood screw or through-bolt mounting.
You may need to place a piece of plywood on the back side of thin fiber­glass panels to reinforce the panel and secure the mounting hardware.

Front

Install the gimbal bracket. Position the bracket so the arms slope to-

ward the front of your unit.

36

Drill a 1-inch (25.4 mm) hole in the dash for the power and transducer
cables. The best location for this hole is immediately under the gimbal
bracket location. This way, the bracket can be installed so that it covers
the hole, holds the cables in position and results in a neat installation.
Some customers prefer to mount the bracket to the side of the cable
hole. It's a matter of personal preference.

72.9
[2.87]

23.4

173.9
[6.85]

[0.92]

137.9
[5.43]

Millimeter

[Inch]

Front view (left) and side view (right) showing dimensions of the unit

when mounted on gimbal bracket.

157.9
[6.22]

56.9
[2.24]

Pass the power cable's bare-wire end down though the hole from the
top. If you want, you can fill in the hole around the cables with a good
marine sealant. (Some marine dealers stock cable hole covers to conceal
the opening.) No matter what type of installation you prefer, be sure to
leave enough slack in the cables to allow tilting or swiveling the unit. If
you choose to fill in the hole, be sure to position the cables against the
rear edge of the hole as you apply the fill material.

Before positioning the bracket, be sure to hold the cables against the
rear edge of the hole. Then, slide the bracket over the hole and butt the
rear of the bracket base firmly against the cables, pinning them in
place against the side of the hole. Finally, fasten the bracket to the
dash. Attach the unit to the gimbal bracket using the supplied gimbal
knobs and washers.

37

Portable Installation

Like many Lowrance products, this unit is capable of portable operation
by using an optional portable power pack (PPP). The power pack and
an optional portable transducer expand the uses for your sonar unit.
The PPP makes it easy to use the unit on your boat or take it to the
dock, on an ice fishing trip or use it as a second sonar in a friend's boat.

Most LEI portable power packs can be used with eight "D" cell alkaline
batteries. Some use an optional sealed, rechargeable battery. For in­formation on the PPP for your unit, see the accessory ordering informa­tion inside the back cover of this manual.

"D" cell battery

Install batteries in typical portable power pack.

MMC or SD Card Memory Card Installation

Your unit uses a MultiMedia Card to store information, such as sonar
logs, custom maps, waypoints, trails and other GPS data. The unit can
also use Secure Digital cards (SD card) to store data.

NOTE:

Throughout this manual, we will use the term MMC, but just re­member your unit can use an MMC or SD card to store data.

Both of these solid-state flash memory devices are about the size of a
postage stamp. An SD card is slightly thicker than an MMC. As this
manual went to press, MMCs were available in storage capacities of 8
MB, 16 MB, 32 MB, 64 MB and 128 MB. SD cards were available in
capacities of 8 MB, 16 MB, 32 MB, 64 MB, 128 MB, 256 MB, 512 MB, 1
GB and 2 GB. Additional MMC cards are available from LEI Extras.
See ordering information inside the back cover of this manual. MMCs
and SD cards are also available at many camera and consumer elec­tronics stores.

38

The MMC slot is located in a compartment on the front of the case. The
compartment door is located at the lower right corner. The following
figure shows a close-up with the door opened.

Thumb

screw

Memory card compartment with a 16 MB MMC card installed.

Insert card face up,

this way

To remove an MMC

1. Open the card compartment door by unscrewing the thumb screw.

The screw should only be finger tight. If it was over-tightened, use a
thumbnail, a coin or a screwdriver to open the door.

2. Just press a finger against the label of the MMC and drag it from the slot.

3. Close the compartment door and fasten the thumb screw finger tight.

To add an MMC or SD Card

1. Open the card compartment door.

2. Grasp the bottom of the MMC and push the top of the card into the

slot. Once the card is started, use your fingernails to slide it the rest of
the way to the left, until it is firmly seated in the slot.

3. Close the compartment door and fasten the thumb screw finger tight.

Other Accessories

Other accessories include MMC cards, MMC card readers and MapCre­ate™ 6 custom mapping software for your computer. LEI offers several
specialty plug-&-play map cards, including lake contour maps and ma­rine coastal charts. A variety of LowranceNET NMEA 2000 electronic
probe sensors and digital gauges are also available.

39

MapCreate™ 6 CD-ROM (left). MMC card reader for USB ports (right).

Face Cover

A white protective cover that snaps on and off the front of the unit is
available. This cover is intended for use when the vehicle is idle.

WARNING:

When the unit is mounted in an unprotected area, such
as an open boat cockpit, the protective face cover must
be removed when the vehicle is moving at high speed.
This includes towing a boat on a trailer at highway
speeds. Otherwise, wind blast can pop off the cover.

NOTE:

When you first turn on the unit, the Map Page appears. If you
would rather start learning about GPS operation, jump to Sec. 6,
Basic GPS Operations. Remember: you don't need to read this
manual from cover-to-cover to get going. We designed it so you can
skip around to the section you want to read.

40

Section 3: Basic Sonar Operation

2

This section addresses the unit's basic sonar operations. The instruc­tions in Sec. 3 are in chronological order. Sec. 4, Sonar Options & Other
Features, will discuss more advanced functions and utilities.

Before you turn on the sonar unit, it is a good idea to learn about the
different keys, the Main Menu, the four Page screens and how they all
work together. BUT, if you just can't wait to get on the water, turn to
the one-page Quick Reference on page 49.

Keyboard

4

8

3

5

MMC slot access door

LMS-339cDF iGPS sonar unit showing map with sonar split screen,
keyboard and access door for the MMC slot.

9

7

6
1

1. PWR/LIGHT – The PWR key turns the unit on and off and activates

the backlight.

2. PAGES – The Pages key helps switch the unit between four page

screens: Satellite Status Page, Navigation Page, Map Page and Sonar
Page.

3. MENU – The Menu key is used to show menus and submenus. It

also gives access to search functions for streets, intersections, addresses
and highway exits.

41

4. ARROW KEYS – The arrow keys are used to navigate through

menus, make menu selections, enter data and move around the map.

5. ENT/ICONS – The Enter key allows you to save data, accept values,

execute menu commands and create event marker icons.

6. EXIT – The Exit key lets you return to the previous screen, clear

data or close a menu.

7. WPT – The Waypoint key is used to access, save and search for way-

points. It also launches the Point-of-Interest (POI) search menus and is
involved in some navigation functions.

8. ZOUT – The Zoom Out key lets you zoom out the screen. On the So-

nar Page, it returns you to a full sonar chart display. On the Map Page,
it lets you see a larger geographic area on the map, but with less detail.

9. ZIN – The Zoom In key lets you zoom in the screen. On the Sonar

Page, it enlarges fish signals and bottom detail. On the Map Page,
zooming in lets you see greater detail in a smaller geographic area on
the map.

Power/lights on and off

To turn on the unit, press PWR. As the unit powers up, the Map Page is
displayed first. To switch to the Sonar Page, press

SONAR|EXIT.

To turn on the backlight, press PWR again. The unit has three backlight
levels. Repeatedly pressing

PWR will cycle through the backlight set-

tings and turn off the backlight.

Turn off the unit by pressing and holding the

PWR key for 3 seconds.

PAGES|→ to

Main Menu

The unit has a Main Menu, which contains function and setup option
commands. The instructions in this section will deal only with sonar
functions, the basic commands that make the unit show sonar signals
on your screen. This sonar unit will work fine right out of the box with
the factory default settings. But, if you want to learn about the various
sonar options, see Sec. 4, Sonar Options & Other Features. (For general
system setup and GPS options, see Sec. 8, System Setup and GPS Setup
Options.)

You can access the Main Menu from any of the four Page screens by
pressing
display, press
"press the Menu key twice." See a full explanation of our instruction
text formatting on pages 11, "How to use this manual."

MENU|MENU. To clear the menu screen and return to the page

EXIT. (Remember, our text style for "MENU|MENU" means

42

Main Menu.

The Main Menu commands and their functions are:

Screen: changes the contrast or brightness of the display screen.

Sounds: enables or disables the sounds for key strokes and alarms and

sets the alarm style.

Transparency: adjusts the level of transparency for menus.

Alarms: turns sonar and GPS alarms on or off and changes alarm

thresholds.

Route Planning: used to plan, view or navigate a route.

My Trails: shows, creates and deletes plot trails. Also used to navigate

or backtrack a trail.

Cancel Navigation: turns off the various navigation commands. Used
to stop navigating after you have reached your destination.

Sonar Setup: sets sonar options.

GPS Setup: sets GPS receiver options.

System Setup: sets general configuration options.

Sun/Moon Calculations: finds the rising and setting time of the sun

and the moon.

Trip Calculator: shows trip status and statistics.

Timers: controls the up timer, down timer and alarm clock settings.

Browse MMC Files: allows you to view files on an MMC card.

Pages

The unit has four Page displays: Satellite Status Page, Navigation Page,
Map Page and Sonar Page. They are accessed by pressing the

key, then using ← → to select the desired Page. (Clear the Pages Menu

by pressing

EXIT.)

PAGES

43

Pages Menu showing Sonar display options.

Satellite Status Page

The Satellite Status Page provides detailed information on the status of
the unit's satellite lock-on and position acquisition. To get to the Satel­lite Status Page: Press the

PAGES key, then use ← → to select STATUS.

This page represents a GPS function, so it is discussed in much greater
detail in Sec. 6.

No matter what Page you are on, a flashing current position indica­tor/question mark symbol and flashing GPS data displays indicate sat­ellite lock has been lost and there is no position confirmed.

WARNING:

Do not begin navigating with this unit until the numbers
have stopped flashing!

Satellite Status Page showing satellite lock-on with a 3D position

acquired (latitude, longitude and altitude), including WAAS reception.

44

Navigation Page

This screen has a compass rose that not only shows your direction of
travel, but also the direction to a recalled waypoint. To get to the Navi­gation Page, press

PAGES|← → to NAVIGATION|EXIT.

This page represents a GPS function, but also has a navigation with
sonar option, which will keep you updated on what is under your boat
as well as where you are going.

Navigation page with Sonar (left). Navigation Page with digital data,

recording a trail, traveling southwest (right).

Map Page

The Map Page screens show your course and track from a bird's-eye
view, on a moving map. By default, this unit shows the map with north
always at the top of the screen. The arrow in the center of the screen is
your present position. It points in the direction you are traveling.

Map Page showing position on Bull Shoals Lake, Arkansas. The full

map option (left). Map with sonar option (right).

45

Map Page is also the default screen that appears when you turn on the
unit. To get to the Map Page from another page, press

MAP|EXIT.

PAGES|← → to

You can display a split screen showing both the Map and Sonar pages
at the same time. This feature is discussed in Sec. 4, Sonar Options &
Other Features.

The Map Page represents a GPS function, so it is discussed in much
greater detail in Sec. 6.

Sonar Page

The Sonar Page displays the sonar chart. This is a cross-section view of
the water column beneath the boat. The chart moves across the screen,
displaying sonar signal echoes that represent fish, structure and the
bottom.

To get to the Sonar Page, press the

SONAR. The Pages Menu also offers five chart display options under the

Sonar Page category. To access them, press
Option Name|

EXIT.

PAGES key, then use ← → to select

PAGES|← → to SONAR|↓ to

The Sonar Page has its own menu, which is used for some advanced
functions and for setting various options. (Sonar Options and other fea­tures are discussed in Sec. 4.) To Access the Sonar Page menu, from the
Sonar Page press

MENU.

Pages Menu (left) showing sonar display options.

Full sonar chart display mode (right).

46

Sonar display options (from left) Split Zoom and Split Frequency.

Sonar chart display options (from left) Digital Data and Flasher.

Sonar Page Menu.

47

Digital data
overlay
(depth &
temperature)

Fish arches

Structure

Surface signal

Bottom signal

Sonar Page in full sonar chart mode.

Surface clutter

Depth scale

In FasTrack, fish
arches show as
horizontal bars.

Zoom bar

FasTrack

bar graph

You can customize how the Sonar Page displays its pictures and other
data in many ways.

We'll discuss all of those features and options in Sec. 4, but to show you
how easy this unit is to operate, the following page contains a 10-step
quick reference that will cover most fish finding situations. The quick
reference describes how your unit will operate with all the sonar fea­tures in their automatic modes, which are set at the factory.

48

Basic Sonar Quick Reference

1. Mount the transducer, antenna and unit. Connect the unit to electric

power and the transducer. (If GPS operation is desired, connect GPS
antenna, too.) Make sure the MMC is in. (See complete installation de­tails beginning on page 13.)

2. Launch your boat.

3. To turn on the unit, press and release

4. Opening screen displays Map Page. Rotate through the four main

Page screens (Map Page, Satellite Status Page, Navigation Page, Sonar
Page) by pressing

PAGES|← → to select Page Name|EXIT. Switch

Pages to display Sonar Page.

5. If GPS data is desired, wait while unit locates satellites and calculates

current position. When the unit acquires position, a tone sounds and a posi­tion acquired message appears.

6. With position acquired (if desired), head for your fishing grounds.

Your unit will automatically display digital depth and surface water
temperature in the top left corner of the screen.

The auto settings will track the bottom, displaying it in the lower por­tion of the screen. The full sonar chart will scroll from right to left,
showing you what's under the boat as you cruise across the water. You
can change the display by:

Zoom in to enlarge the chart for more detail: press
Zoom out to return to full chart mode: press

7. Watch the display for the appearance of fish symbols (or arches, if

Fish I.D. is turned off). When you see fish symbols or arches, you've
found fish! Stop the boat and get your lure or bait into the water at the
depth indicated on the sonar chart.

8. Gauge the fish depth by visually comparing the fish symbols or

arches with the depth scale on the right side of the screen.

9. If you are drifting at a very low speed or anchored, you are not mov-

ing fast enough for a fish to return the tell-tale fish arch signal. As you
drift over a fish, or as a fish swims through the transducer's signal
cone, the fish echo will appear as a straight line suspended between the
surface and the bottom when Fish I.D. is turned off.

10. To turn off the unit, press and hold

PWR key.

ZIN.

ZOUT.

PWR key for three seconds.

49

Sonar Operations

As you can see from the quick reference on the previous page, basic operation
is pretty easy, right out of the box. If you are a sonar novice, try operating the
unit with the factory defaults until you get a feel for how it's working.

As you are learning the basics, there is one setting you might want to
tinker with from time to time — Sensitivity.

Sensitivity controls the unit's ability to pick up echoes. If you want to see
more detail, try increasing the sensitivity, a little at a time. There are situa­tions when too much clutter appears on the screen. Decreasing the sensitivity
can reduce the clutter and show the strongest fish echoes, if fish are present.
As sensitivity is adjusted, you can see the difference on the scrolling chart.

Fig. 1

Fig. 3

Fig. 2

Fig. 4

These figures show results of different sensitivity levels on the same lo­cation. Fig. 1: Sensitivity at 88 percent, determined by Auto Sensitivity.

Typical of full auto mode. Fig. 2: Sensitivity set at 75 percent. Fig. 3: Sen-

sitivity set at 50 percent. Fig. 4: Sensitivity set at 100 percent.

50

You can change the sensitivity level whether you are in Auto Sensitivity
mode or Manual Sensitivity mode. The adjustment method works the
same in both modes, but it gives you slightly different results.

Adjusting sensitivity in Auto Sensitivity Mode is similar to manually ad­justing a car's speed with the accelerator pedal while cruise control is on.
You can tell the car to run faster, but when you let off the gas the cruise
control automatically keeps you from running slower than the minimum
speed setting. In the unit, auto mode will let you increase sensitivity to 100
percent, but the unit will limit your minimum setting. This prevents you
from turning sensitivity down too low to allow automatic bottom tracking.
When you change the setting with auto turned on, the unit will continue to
track the bottom and make minor adjustments to the sensitivity level, with
a bias toward the setting you selected.

Adjusting sensitivity in Manual Sensitivity Mode is similar to driving a
car without cruise control — you have complete manual control of the
car's speed. In the unit, manual mode allows you to set sensitivity at
100 percent (maximum) or zero percent (minimum.) Depending on wa­ter conditions, the bottom signal may completely disappear from the
screen when you reduce sensitivity to about 50 percent or less!

Try adjusting sensitivity in both auto and manual modes to see how
they work.

To adjust sensitivity:

1. Press

MENU|ENT.

2. The Sensitivity Control Bar appears. Press ↑ ↓ to adjust sensitivity.

When it's set at the desired level, press

EXIT.

Sonar Menu with Sensitivity command selected (left). The Sensitivity

Control Bar (right).

51

NOTE:

If you want to change the sensitivity in Manual Mode, turn off Auto
Sensitivity. From the Sonar Page, press

|ENT|↑ to SENSITIVITY|ENT. Press ↓ ↑ to pick a different sensi-

TIVITY

tivity setting. When it's set at the desired level, press

MENU|↓ to AUTO SENSI-

EXIT.

Important Tip:

While you are experimenting with settings, it is possible to scram­ble them so the sonar picture disappears from your screen. If that
happens, remember it is easy to switch back to full automatic op­eration by restoring the factory auto settings.

To Restore Factory Settings

1. Press MENU|MENU|↓ to SYSTEM SETUP|ENT|↓ to RESET OP-

TIONS

|ENT.

2. A confirmation message will appear. Press ← to
tions are reset and the unit reverts back to the Map Page at the
4000-mile zoom. Sonar logs and saved GPS data will be unchanged.

Fish Symbols vs. Full Sonar Chart

You may have noticed in the quick reference that we used fish arches in
full sonar chart mode for our example, and not the popular Fish I.D.
fish symbol feature.

Fish I.D. is an easier way for a sonar novice to recognize a fishy signal
return when he sees it. However, locating fish by symbol only has some
limitations.

Your sonar unit's microprocessor is remarkably powerful, but it can be
fooled. Some of the echoes calculated to be fish could be tree limbs or tur­tles! To see what's under your boat in maximum detail, we recommend

you turn off Fish I.D. and begin learning to interpret fish arches.

Fish I.D. is most handy when you're in another part of the boat or per­forming some task that prevents you from watching the sonar screen.
Then, you can turn on Fish I.D. and the audible fish alarm. When that
lunker swims under your boat, you'll hear it!

Fish I.D. can also be useful when you want to screen out some of the
sonar detail gathered by your unit. For example, in one case fisherman
in San Francisco Bay saw clouds of clutter in the water but no fish
arches. When a down rigger was pulled up, it brought up several small
jellyfish. The fisherman switched their sonar to Fish I.D., which
screened out the schools of jellyfish and clearly showed the game fish
there as fish symbols.

YES|ENT. All op-

52

Other Free Training Aids

The sonar options section discusses Fish I.D., fish alarms and other
features in greater detail. If you or a friend has Internet access, you can
also learn more about interpreting what you see on your sonar screen.
Visit our web site, www.lowrance.com. Be sure to check out the free
Sonar Tutorial, which includes animated illustrations and more pic­tures of actual sonar returns, all described in detail. There's even a
"printer friendly" version of the tutorial available on our web site…it
makes a great supplement to this operation manual!

You can also download a free copy of our Sonar Viewer software. This
PC-based software application plays back any sonar chart log recorded
with a Lowrance sonar product. Features include:

• Adjustable range, zoom, sensitivity, color line, noise rejection,

surface clarity, etc. of the recorded file.

• Color interpretation of sonar signals can be user defined.

• Operates like a Windows Multimedia Player with forward, re-

verse, pause, fast forward, fast reverse, and scroll buttons.

• Adjustments update the entire record displayed.

• Can print in full color.

• Window can dynamically be sized on your monitor.

• Mouse cursor shows GPS position, depth and sounding number

anywhere on the visible record.

For the ultimate training aid, be sure to download the free emulator
software for your unit. Aside from being fun, this program can help you
learn both basic and advanced operations without burning boat fuel!
Lowrance is one of the first sonar manufacturers to provide this type of
training tool for customers.

This PC application simulates the actual sonar/GPS unit on your com­puter. You can run it from your computer keyboard or use your mouse
to press the virtual keys. Easy download and installation instructions
are available on our web site.

The emulator works exactly like your real sonar/GPS unit. Using the
Sonar Simulator and GPS Simulator features, it allows you to play
back sonar logs, run GPS routes and trails and create real waypoints
you can use in the field! You can even take snapshots of the Sonar
Chart and print them or e-mail them to friends.

53

Notes

54

Section 4: Sonar Options & Features

ASP (Advanced Signal Processing)

The ASP feature is a noise rejection system built into the sonar unit
that constantly evaluates the effects of boat speed, water conditions
and interference. This automatic feature gives you the best display pos­sible under most conditions.

The ASP feature is an effective tool in combating noise. In sonar terms,
noise is any undesired signal. It is caused by electrical and mechanical
sources such as bilge pumps, engine ignition systems and wiring, air
bubbles passing over the face of the transducer, even vibration from the
engine. In all cases, noise can produce unwanted marks on the display.

The ASP feature has four settings — Off, Low, Medium and High. If
you have high noise levels, try using the "High" ASP setting. However,
if you are having trouble with noise, we suggest that you take steps to
find the interference source and fix it, rather than continually using the
unit with the high ASP setting.

There are times when you may want to turn the ASP feature off. This
allows you to view all incoming echoes before they are processed by the
ASP feature.

Sonar Menu with Sonar Features selected (left). In the Sonar

Features menu, Noise Rejection (ASP) set to low setting (right).

To change the ASP level:

1. From the Sonar Page, press

2. Press ↓ to

3. Press ↓ ↑ to select a setting, then press

4. To return to the previous page, press

NOISE REJECTION|ENT.

MENU|↓ to SONAR FEATURES|ENT.

ENT.

EXIT|EXIT.

55

Alarms

This unit has three different types alarms, Sonar, GPS and NMEA

2000. There are three Sonar alarms: Fish Alarm, Zone Alarm and

Depth Alarm.
The Fish Alarm will sound when the Fish I.D. feature determines an

echo is a fish. The Zone Alarm consists of a blue bar on the side of the
screen. Any echo on the chart that appears inside this bar triggers the
alarm. The Depth Alarm has both a Shallow and a Deep setting. Only
the bottom signal will trigger this alarm. It is most useful as an anchor
watch or shallow water alert.

Depth Alarms

The depth alarms sound a tone when the bottom signal goes shallower
than the shallow alarm's setting or deeper than the deep alarm's set­ting. For example, if you set the shallow alarm to 10 feet, the alarm will
sound a tone if the bottom signal is less than 10 feet. It will continue to
sound until the bottom goes deeper than 10 feet.

The deep alarm works just the opposite. It sounds a warning tone if the
bottom depth goes deeper than the alarm's setting. Both depth alarms
work only off the digital bottom depth signals. No other targets will trip
these alarms. These alarms can be used at the same time or individually.

Main Menu and Sonar Alarms command (left).

The Sonar Alarms menu (right).

To adjust and turn on the shallow alarm:

1. Press MENU|MENU|↓ to ALARMS|ENT|↓ to SONAR ALARMS|ENT.

2. Press → to

SHALLOW ALARM DEPTH|ENT.

3. Press ↑ ↓ to change the first number, then press → to the next num-

ber and repeat until the depth is correct, then press

ENT.

56

4. Press ← to

SHALLOW ALARM ENABLED|ENT. Press EXIT repeatedly to get

back to the main page display.

To adjust and turn on the deep alarm:

1. Press MENU|MENU|↓ to ALARMS|ENT|↓ to SONAR ALARMS|ENT.

2. Press ↓ → to

DEEP ALARM DEPTH|ENT.

3. Press ↑ ↓ to change the first number, then press to the next number

and repeat until the depth is correct, then press

4. Press ← to

DEEP ALARM ENABLED|ENT. Press EXIT repeatedly to get back

ENT.

to the main page display.

Zone Alarm

The zone alarm is triggered when any echo passes inside the zone
alarm bar, shown on the right side of the screen.

To adjust and turn on the zone alarm:

1. Press MENU|MENU|↓ to ALARMS|ENT|↓ to SONAR ALARMS|ENT.

2. Press ↓ → to

ADJUST ZONE|ENT.

Sonar Alarms menu with Adjust Zone command selected (left).

Adjust Zone Alarm selection box with Upper selected (right).

3. To set the upper boundary for the Zone Alarm, use ← → to select

UPPER, then press ↑ ↓ to move the top of the bar to the desired depth.

4. To set the lower boundary for the Zone Alarm, use ← → to select

LOWER,

then press ↑ ↓ to move the bottom of the bar to the desired depth.

5. Press

EXIT|← to ZONE ALARM ENABLED and press ENT. Press EXIT re-

peatedly to get back to the main page display. Now, any echo — fish,
bottom or structure — within the zone alarm's depth range will trigger
the zone alarm.

57

Fish Alarm

Use fish alarm to receive an audible alarm when fish or other objects
are detected by the Fish I.D. feature (Fish I.D. must be turned on for
the Fish Alarm to work). A different tone sounds for each fish symbol
size shown on the display.

To turn on fish alarm:

1. Press MENU|MENU|↓ to ALARMS|ENT|↓ to SONAR ALARMS|ENT.

2. Press ↓ to

FISH ALARM|ENT. Press EXIT repeatedly to get back to the

main page.

NMEA 2000 Alarm

The NMEA 2000 Alarm can monitor multiple EP-10 Fuel Flow and EP­15 Fluid Level sensors. You can set a threshold for each alarm in its
corresponding Percent box. Thresholds give you control over when the
alarm will go off. You may want the alarm to go off when the black wa­ter tank is filled to 75 percent of its capacity, likewise, you may want to
know when the fuel level falls below 30 percent of tank capacity.

To get to the NMEA 2000 Alarms menu, press

ALARMS and press ENT. Choose NMEA 2000 ALARMS and press ENT.

MENU|MENU, select

NMEA 2000 Alarms selected from alarms menu (left). NMEA 2000

Alarms menu (right).

1. With the Fluid Level Device window highlighted, press ENT and use

↑ ↓ to select the device you want to monitor, then press

2. To enable the Full Alarm, highlight

press

ENT to turn on (check) the alarm. Press → to the Percent box and

press

ENT. Use the ↑ ↓ keys to select the first number, then press → to

FULL ALARM Enabled box and

ENT.

move to the next number. When the desired percentage has been en­tered, press

ENT.

58

3. To enable the Empty Alarm, highlight the

and press
and press

ENT to turn on (check) the alarm. Press → to the Percent box

ENT. Use the ↑ ↓ keys to select the first number, then press

EMPTY ALARM Enabled box

→ to move to the next number. When the desired percentage has been
entered, press

ENT.

Tip

You do not have to set both the Full and Empty alarms. Choose Full
and Empty alarms or activate them individually.

Calibrate Speed

The speed sensor can be calibrated to compensate for inaccuracies. Be­fore you change the setting, first calculate the percentage that the
speed is off. You will enter this percentage in a moment.

For example, if you figure the sensor is reading 10 percent faster than
actual speed, you will enter – 10 in the calibration window. If the sen­sor is reading 5 percent slower than true speed, you will enter + 5 in
the window.

A good way to gauge your speed sensor's performance is to compare its
reading with the ground speed measured by your unit's GPS functions.
When you make a run to compare GPS ground speed to speed sensor
speed, perform your test in relatively calm water free of current, if pos­sible. (Unless, of course, you are taking the speed of current into con­sideration when making your calculation.) After you have a correction
figure, here's how to enter it:

1. Press

SPEED|ENT.

2. Enter the number you calculated earlier. Press ↑ ↓ to change the

first character (+ or –), then press → to move the cursor to the next
number and repeat until the percentage is correct, then press

MENU|MENU|↓ to SONAR SETUP|ENT|↓ to CALIBRATE WATER

EXIT.

Chart Speed

The rate that echoes scroll across the screen is called the chart speed.
The default is maximum; we recommend that you leave the speed set
there for virtually all fishing conditions.

However, you might consider experimenting with chart speed when you
are stationary or drifting very slowly. You may sometimes achieve bet­ter images as you slow down the chart speed to match how fast you are
moving across the bottom.

If you are at anchor, ice fishing or fishing from a dock, experiment with
a chart speed around 50 percent. If you are drifting slowly, try a chart
speed around 75 percent. When you are stationary and a fish swims

59

through the sonar signal cone, the image appears on the screen as a
long line instead of a fish arch. Reducing the chart speed may result in
a shorter line that more closely resembles a regular fish return.

Sonar Page menu with Chart Speed command selected (left).

Chart Speed Control Bar (right).

If you do experiment with chart speed, remember to reset it to maxi­mum when you resume trolling or moving across the water at higher
speed.

1. From the Sonar Page, press

MENU|↓ to CHART SPEED|ENT.

2. The Chart Speed Control Bar appears. Press ↑ ↓ to make adjust-

ments to chart speed.

3. When it's set at the desired level, press

EXIT.

ColorLine

ColorLine lets you distinguish between strong and weak echoes. It
paints a brighter color on targets that are stronger than a preset value.
This allows you to tell the difference between a hard and soft bottom.
For example, a soft, muddy or weedy bottom returns a weaker signal
which is shown with a narrow, colored line (dark blue tinged with red
or a little yellow.) Since fish are among the weakest echoes, they show
up mostly as blue arches. A hard bottom or other relatively hard target
returns a strong signal which causes a wider brightly colored line (red­dish yellow to bright yellow.)

If you have two signals of equal size, one with red to yellow color and
the other without, then the target with brighter color (yellow) is the
stronger signal. This helps distinguish weeds from trees on the bottom,
or fish from structure. ColorLine is adjustable. Experiment with your
unit to find the ColorLine setting that's best for you.

60

Sonar Page menu with ColorLine command selected (left).

The ColorLine control bar (right).

To adjust the ColorLine level:

1. From the Sonar Page, press

MENU|↓ to COLORLINE|ENT.

2. The ColorLine Control Bar appears. Press ↑ ↓ to adjust Colorline.

3. When it's set at the desired level, press

Thin or no ColorLine

EXIT.

Wider
ColorLine

A small amount of ColorLine indicates a soft bottom, probably sand or

mud (left). The wider ColorLine indicates a harder bottom (right).

Depth Cursor

The depth cursor consists of a horizontal line with a digital depth box
on the right side. The numbers inside the box show the depth of the
cursor.

61

Cursor line

Depth box

Sonar Page menu with Depth Cursor selected (left). Sonar chart with

active depth cursor (right). The cursor is set at 34.64 feet deep.

The cursor can be moved to any location on the screen, letting you pin­point the depth of a target.

1. From the Sonar Page, press

MENU|↓ to DEPTH CURSOR|ENT.

2. The depth cursor appears. Press ↓ ↑ move the Depth Cursor.

3. To clear the depth cursor, press

EXIT.

Depth Range - Automatic

When turned on for the first time, the bottom signal is automatically
placed in the lower half of the screen. This is called Auto Ranging and
is part of the automatic function. pending upon the bottom depth and
the current range, you can change the range to a different depth.

Sonar Page menu with Depth Range command selected (left). The

Depth Range Control Scale (right).

62

1. From the Sonar Page, press

MENU|↓ to DEPTH RANGE|ENT.

2. The Depth Range Control Scale appears. Press ↑ ↓ to select a differ-

ent depth range. A blue bar highlights the selected range. The shaded
numbers cannot be selected.

3. When the new range is selected, press

EXIT to close the menu.

Depth Range - Manual

You have complete control over the range when the unit is in the man­ual mode. There are 16 depth ranges, from 5 to 4,000 feet.

To switch to Manual Depth Range:

1. First, turn off automatic depth range. From the Sonar Page, press

MENU|↓ to AUTO DEPTH RANGE|ENT.

2. Press ↑ to

DEPTH RANGE|ENT and the Depth Range Control Scale ap-

pears.

3. Press ↓ ↑ to select a different depth range. A blue bar highlights the

selected range.

4. When the new range is selected, press

EXIT to close the menu.

NOTE:

The sonar's depth capability depends on the water, bottom condi­tions, transducer installation and other factors.

Depth Range - Upper and Lower Limits

Virtually any segment of the water column can be displayed by using
the upper and lower limit feature. This lets you pick the shallow and
deep depth range limits that are shown on the screen, provided there is
at least 10 feet between the upper and lower limit you select. For ex­ample, a range from 12 feet to 34 feet could be used.

Changing the upper and lower limits gives you far greater control over
the depth range. This feature lets you zoom in the display in almost
unlimited combinations. Nearly any segment of the water column, from
the surface to the bottom can be shown.

63

Sonar Page Menu with Upper and Lower Limits command selected

(left). Sonar Chart Limits menu with Upper Limit selected (right).

To change the upper and lower limits:

1. From the Sonar Page, press

MENU|↓ to UPPER AND LOWER LIMITS|ENT.

The Sonar Chart Limits menu appears, with Upper Limit selected.

2. To set the upper limit, press

ENT. Press ↑ ↓ to change the first num-

ber, then press → to move the cursor to the next number and repeat
until the depth is correct, then press

3. To set the lower limit, press ↓ to

EXIT.

LOWER LIMIT|ENT. Press ↑ ↓ to change

the first number, then press → to move the cursor to the next number
and repeat until the depth is correct, then press

EXIT repeatedly.

To turn off upper and lower limits:

From the Sonar Page, press

Area "zoomed"

MENU|↓ to AUTO DEPTH RANGE|ENT|EXIT.

Fish arches

Display in auto depth range mode (left). Display zoomed with Upper

and Lower Limits focused on water column from 20 to 40 feet (right).

64

FasTrack

This feature automatically converts all echoes to short horizontal lines
on the display's far right side. The graph on the rest of the screen con­tinues to operate normally. FasTrack gives you a rapid update of condi­tions directly under the boat. This makes it useful for ice fishing or
when you are fishing at anchor. When the boat is not moving, fish sig­nals are long, drawn out lines on a normal chart display. FasTrack con­verts the graph to a vertical bar graph that, with practice, makes a use­ful addition to fishing at a stationary location.

Surface clutter

Fish arches

Structure

In FasTrack, fish
arches show as
horizontal bars.

Bottom signal

FasTrack

Sonar Page showing FasTrack.

bar graph

Fish I.D. (Fish Symbols & Depths)

The Fish I.D. feature identifies targets that meet certain conditions as
fish. The microcomputer analyzes all echoes and eliminates surface
clutter, thermoclines, and other signals that are undesirable. In most
instances, remaining targets are fish. The Fish I.D. feature displays
fish symbols on the screen in place of the actual fish echoes.

There are several fish symbol sizes. These are used to designate the
relative size between targets. In other words, Fish I.D. displays a small
fish symbol when it thinks a target is a small fish, a medium fish sym­bol on a larger target and so on.

The sonar's microcomputer is sophisticated, but it can be fooled. It can't
distinguish between fish and other suspended objects such as trotlines,
turtles, submerged floats, air bubbles, etc. Individual tree limbs ex­tending outwards from a group of limbs is the hardest object for the
Fish I.D. feature to distinguish from fish.

You may see fish symbols on the screen when actually, there are no
fish. The reverse is also true. The illustrations on the next page show
how Fish I.D. can actually miss fish that are present.

65

Does that mean Fish I.D. is broken? No — the feature is interpreting
sonar returns in a specific way to help take some of the work out of
reading the screen. Remember: Fish I.D. is one of the many tools we
provide so you can analyze your sonar returns for maximum fish find­ing information. This and other features can help you successfully "see"
beneath the boat under varied water and fishing conditions. So, prac­tice with the unit in both the Fish I.D. mode and without to become
more familiar with the feature. Fish I.D. is off by default.

Sonar Features menu with Fish I.D. Symbols selected.

To turn the Fish I.D. feature on:

1. From the Sonar Page, press

2. Press → to

FISH SYMBOLS|ENT|EXIT|EXIT.

MENU|↓ to SONAR FEATURES|ENT.

To turn off Fish I.D., repeat the instructions in step 2.

FishTrack

The FishTrack feature shows the depth of a fish symbol when it ap­pears on the display. This lets you accurately gauge the depth of tar­gets. This feature is available only when the Fish I.D. feature is on. The
default setting for FishTrack is off.

To turn on FishTrack:

66

Fig. 1 A

Fig. 1 B

Many fish

arches visible

Fewer fish

symbols visible

Fig. 2 A

Fish arches

above structure

Figures 1A and 2A (left) show Sonar Page in normal chart mode. Figures

1B and 2B (right) show the same underwater scene with Fish I.D.

turned on. Note how arches are replaced with symbols.

Fig. 2 B

No fish shown

FasTrack graph

confirms fish

NOTE:

These steps will turn on FishTrack and Fish I.D. at the same time.

1. From the Sonar Page, press

2. Press → ↓ to

FISH DEPTHS|ENT|EXIT|EXIT.

MENU|↓ to SONAR FEATURES|ENT.

To turn off FishTrack, repeat the instructions in step 1. Turning off
FishTrack in this manner will not turn off Fish I.D. symbols.

67

Symbols with

FishTrack depths

Sonar Features menu with Fish I.D. Depths selected (left). When the

check box to the left is checked, the feature is on. Sonar Page with Fish

I.D. symbols and FishTrack depths turned on (right).

Frequency (LMS-339cDF only)

The LMS-339cDF transducer can operate at both 200 kHz and 50 kHz.
The 200 kHz frequency has a 12° cone angle and the 50 kHz frequency
has a 35° cone angle.

The default frequency is 200 kHz, which is best for use in shallow water
(about 300 feet or less). This frequency is the best choice for about 80
percent of the fresh and salt water sport fishing applications. When you
get into very deep salt water, 300 to 500 feet or deeper, the 50 kHz fre­quency is the best choice.

The 200 kHz transducer will give you better detail and definition, but
less depth penetration. The 50 kHz transducer will give you greater
depth penetration, but a little less detail and less definition. (Remember,
all sonar units typically read deeper in fresh water than in salt water.)

There is a common exception to these rules of thumb. Some fishermen
on freshwater lakes (or the ocean) using downriggers like to see them
on the sonar. In many of those cases, you'll see a 50 kHz transducer
frequency in use because the wider cone angle lets them watch the bait.

68

Sonar Features menu with a frequency of 200 kHz selected.

To change the frequency setting to 50 kHz:

1. From the Sonar Page, press

2. Press → ↓ to

3. Press

EXIT|EXIT to close the menu.

50 KHZ|ENT.

MENU|↓ to SONAR FEATURES|ENT.

To change the frequency setting to 200 kHz:

1. From the Sonar Page, press

2. Press → ↓ to

3. Press

EXIT|EXIT to clear the menu.

200 KHZ|ENT.

MENU|↓ to SONAR FEATURES|ENT.

HyperScroll

See the entry on Ping Speed, which controls the HyperScroll feature.

Log Sonar Chart Data

If you have an MMC installed in the unit, the sonar data shown on the
screen can be saved to the MMC. This can be played back at any time.
If you have a personal computer and Internet access, visit our web site,
www.lowrance.com and download the free Sonar Viewer and emulator
for your unit. These programs will allow you to replay sonar logs on
your personal computer.

69

Sonar Page menu with the Log Sonar Chart Data command selected

(left). Sonar Chart Logging menu, with the Start Logging command

selected (right). The menu says the MMC has 5.42 MB of free space,

which will record the scrolling chart for 28 minutes and 44 seconds.

To record or log chart data:

1. Press

2. To record data using the default settings, press

MENU|↓ to LOG SONAR CHART DATA|ENT.

ENT. The menu clears

and the Sonar Page title bar shows the name of the file you are record­ing. Warning messages will appear as recording time starts to run out.

NOTE:

You can change any of the settings by using the cursor arrows to
highlight different commands. Select
change the name. Select

CHART QUALITY if you want to lower the file

FILE NAME if you want to

quality and record for a longer period of time. After you have
changed the settings, select

START LOGGING and press ENT.

NMEA 2000

On the Sonar menu, the NMEA 2000 entry provides a way to monitor,
configure and calibrate devices on the LowranceNet. For more informa­tion, see the document, Instructions for Using LowranceNET

2000 Devices with LMS-334, LMS-339 and GlobalMap 3600. If the
document is missing, download it free at www.lowrance.com or contact
customer service.



NMEA



Noise Rejection

See the entry on Advanced Signal Processing in this section.

Overlay Data

On any Page display except Satellite Status, you can float or overlay
additional GPS or navigation data on the screen with the Overlay Data

70

command. For example, if you left your watch at home, you could dis­play the local time on top of the map. Or, if you wanted to see details
about your route and trip, you could show your bearing, course, average
speed and trip distance.

The various data available from your unit are divided into categories in
the Overlay Data menu. These categories include GPS Data, Naviga­tion, Trip Calculator, Time, Sonar Data and Miscellaneous Data.

You can select items from any of these categories for display, in any
combination — the category divisions are there only to help you sort
through the information.

Overlay Data, with Navigation and Sonar Data

categories expanded.

To overlay information on your screen:

1. Press

MENU|↓ to OVERLAY DATA|ENT.

2. If you currently have any overlay data on your screen, it will be

listed here. Select

(ENTER TO ADD) and press ENT. The data viewer shows

information categories with "+" or "–" symbols next to each category
name. A category with a "+" next to it is expandable, meaning its con­tents are hidden.

Selecting the category name and pressing

ENT will show the category's

contents, so you can choose items within it. An expanded category (one
with a "–" next to its name) can be collapsed to hide its contents. Just
select the category name and press

ENT.

3. Expand any categories that might contain data you want to display.

Then press ↓ ↑ to select a data option.

4. With the data option highlighted, press

ENT to turn on (check) and

turn off (uncheck). As you turn it on, the data will appear on top of the
screen.

71

Every Page display has a maximum number of items you can show us-

arrow

ing the Overlay Data command.

5. After the desired changes are made, press

EXIT|EXIT to return to the

page display.

Ent to Add selected (left). Data Viewer menu (center). Select a category

and press ENT. Next, select information to show on screen and press

ENT to check it and turn it on (right).

Steering

Boat cruising Puget Sound, Washington with Overlay Data turned on

(left). This example shows Depth, Ground Speed and the Steering Ar-

row. Sonar Page displaying Depth, Ground Speed and Track (right).

To remove overlaid data:

1. While on the Page that shows the item or items you want to remove,

press

MENU|↓ to OVERLAY DATA|ENT.

2. You'll see a list of the overlay data currently displayed. Select the

item you want to remove from your display and press

ENT|ENT to re-

move the data. To remove another item, select the item and press

ENT|ENT.

3. When you have finished removing all the items you want from the

screen, press

EXIT to return to the page display.

72

NOTE

You can also remove data directly from the Data Viewer menu by un­checking the data option you would like to remove.

Overlay Data Shown, with Date option selected (left).

Remove highlighted on Data information window (right).

To move overlaid data:

You may find it useful to rearrange data on the display window.

1. From one of the Map Pages, press

MENU|↓ to OVERLAY DATA|ENT.

2. You'll see a list of the overlay data currently displayed. Select the

item you want to move and press

ENT|→ to MOVE|ENT.

3. The data begins to flash on your screen. Use any combination of ↑ ↓,

← → to move the data to a new location on the screen.

4. When satisfied, press

EXIT|EXIT.

NOTE:

The Customize command and the Overlay Data command both use
the same information categories. The difference between the two
commands is Customize changes information in digital data boxes,
while Overlay Data changes information displayed directly on the
screen. See Customize Page Displays, on page 82, for information
on customizing data boxes.

73

Depth selected in the overlay data shown menu (left). By pressing ← →

the size of the Depth display will increase or decrease on the display.

The size of the Depth text has been changed to enormous (right).

To change displayed data font size:

1. From the Map or Sonar page, press MENU|↓ to OVERLAY DATA|ENT.

2. Select Data Type, then press ← → to scroll through the four data

size options: small, medium, large and enormous.

The selected data type will be displayed in the new size. To change the
font size for another Data Type, repeat these steps, beginning with step
two above.

3. To return to the previous page, press

EXIT.

NOTE:

Some data types can be displayed in only one font size. If that is the
case, the Data Size box will not be displayed for that data type.

Ping Speed & HyperScroll

Ping Speed controls the rate at which the transmitter and transducer
broadcast sonar sound waves — pings — into the water. The unit has a
default ping speed of 50 percent. At normal boating speeds, this auto­matically provides enough return echoes to refresh the screen and scroll
the chart at maximum chart speed.

However, when you are running at high speeds, or just want the fastest
possible screen update, you may want to use the HyperScroll feature.
When you change the Ping Speed to any setting greater than 50 per­cent, the unit automatically enters HyperScroll mode.

These faster ping rates allow you to maintain a high-detail picture on
the screen, and the screen refresh rate and chart scroll speed can keep
pace with the boat as it moves quickly over the bottom terrain.

74

When using HyperScroll, you may also need to manually decrease the
sensitivity for optimum performance. Depending on water depth and
other conditions, HyperScroll may cause a second bottom echo to return
to the transducer during the next ping cycle, or sounding. This can result
in a large amount of clutter appearing on the screen. If this occurs, just
decrease the sensitivity to a level that eliminates the clutter. When you
turn HyperScroll off, you can return to your original sensitivity level.

Sonar Menu with Ping Speed command selected (left).

Ping Speed Control Bar at default setting (right).

To change Ping Speed:

1. From the Sonar Page, press

MENU|↓ to PING SPEED|ENT.

2. The Ping Speed Control Bar appears. Press ↑ ↓ to adjust Ping Speed.

When it's set at the desired level, press

EXIT.

To turn off HyperScroll:

1. From the Sonar Page, press

MENU|↓ to PING SPEED|ENT.

2. The Ping Speed Control Bar appears. Press ↓ to decrease ping speed

to 50 percent. To reactivate Hyperscroll use ↑ to increase ping speed to
greater than 50 percent. When it's set at the desired level, press

EXIT.

When you boost ping speed and switch into HyperScroll, the width of
the FasTrack bar graph display doubles in width at the right side of the
screen. This allows you to better see the virtually instantaneous sonar
returns, just as you would on a flasher sonar unit. For more informa­tion on FasTrack, see its entry in this section.

To adjust Sensitivity:

1. From the Sonar Page, press

MENU|ENT.

2. The Sensitivity Control Bar appears. Press ↓ ↑ to adjust sensitivity.

When it's set at the desired level, press

EXIT.

75

Reset Options

This command is used to reset all features, options and settings to their
default settings. This is useful when you have changed several settings
and want to return the unit to basic automatic operation.

1. Press

2. Press ← to

3. All the menus are cleared and the unit reverts to the Map Page at

the 4000-mile zoom, just as if you had turned it on for the first time. All
options have been returned to the factory settings.

System Setup menu with Reset Options command selected (left). The

NOTE:

MENU|MENU|↓ to SYSTEM SETUP|ENT|↓ to RESET OPTIONS|ENT.

YES|ENT.

Reset Options dialog box with Yes selected (right).

Reset Options does not erase any waypoints, routes, plot trails, or
sonar logs.

Reset Water Distance

The sonar chart's Digital Data display option includes a box that shows
distance traveled, called Water Distance. This information is calculated
from an optional water speed sensor, not the GPS. The Water Distance
window can be reset to zero using the Reset Water Distance command.

Press

TANCE

MENU|MENU|↓ to SONAR SETUP|ENT|↓ to RESET WATER DIS-

|ENT. The menus are cleared and the water distance is reset to 0.00.

Set Keel Offset

This unit measures water depth from the face of the transducer. Since
the transducer is installed below the water surface, the distance dis­played by the digital depth, chart depth scale, chart cursor or fish sym­bols is not the exact water depth.

76

If the transducer is 1 foot below the surface, and the screen shows the
water depth as 30 feet, then the actual depth is 31 feet.

On sailboats or other large vessels with deep drafts, the distance be­tween the transducer installation and the keel or lower engine unit can
be several feet. In those cases, an inexact depth reading could result in
grounding or striking underwater structure. The Keel Offset feature
eliminates the need for the navigator to mentally calculate how much
water is under his keel.

Keel Offset lets you calibrate the digital depth, chart depth scale, chart
cursor depth and fish symbol depth displayed on the screen. To calibrate
the depth indicators, first measure the distance from the face of the
transducer to the lowest part of the boat. In this example, we will use 3.5
feet. This will entered as a negative 3.5 feet, which makes the depth indi­cators perform as if the transducer's lower in the water than it really is.

1. Press

OFFSET|ENT.

MENU|MENU|↓ to Sonar Setup ENT. Use ↓ to select SET KEEL

2. The Keel Offset dialog box appears. Press ↓ to change the plus (+)

sign to a minus (–) sign.

3. Press → to the first number, then press ↑ to change the number to 3

4. Press → to the second number, then press ↑ to change the number to

5, then press

EXIT. The depth indicators now accurately show the depth

of water beneath the keel.

NOTE:

If knowing the exact depth of water beneath the keel is less important,
you can calibrate the depth indicators so that they show the actual wa­ter depth from surface to bottom. To do this, first measure the distance
from the face of the transducer up to the surface (the water line on the
boat). In this example, we will use 1.5 feet. This will be entered as a
positive 1.5 feet, which makes the depth indicators perform as if the
transducer's higher in the water than it really is.

1. Press

OFFSET|ENT.

MENU|MENU|↓ to Sonar Setup ENT. Use ↓ to select SET KEEL

2. The Keel Offset dialog box appears with a plus (+) sign at the
front of the box.

3. Press → to the first number, then press ↑ to change the number
to 1.

4. Press → to the second number, them press ↑ to change the num­ber to 5, then press

EXIT. The depth indicators now accurately show

the water depth from surface to bottom.

77

Sensitivity & Auto Sensitivity

The sensitivity controls the ability of the unit to pick up echoes. Sensi­tivity can be adjusted, because water conditions vary greatly. A low
sensitivity level (from zero to 50 percent) excludes much of the bottom
information, fish signals, and other target information.

High sensitivity levels let you see this detail, but it can also clutter the
screen with many undesired signals. Typically, the best sensitivity level
shows a good solid bottom signal with Colorline and some surface clutter.

Automatic Sensitivity

The default sensitivity mode is automatic. The unit bases the sensitiv­ity level on water depth and conditions. When the unit is in the auto­matic mode, sensitivity is automatically adjusted to keep a solid bottom
signal displayed, plus a little more power. This gives it the capability to
show fish and other detail.

However, situations occur when it becomes necessary to increase or de­crease the sensitivity. This typically happens when you want to see
more detail, so an increase in sensitivity is indicated. Or, wave action
and boat wakes can create enough tiny air bubbles to clutter much of
the water column. In that case, a decrease in sensitivity is indicated to
reduce some of the clutter.

The control bar used to adjust sensitivity up or down is the same
whether the unit is in the automatic or manual mode. In automatic you
can adjust sensitivity up to 100 percent but the unit will limit your
minimum setting. In auto, the unit will continue to make small ad­justments, allowing for the setting you selected.

In manual mode, you have complete control over sensitivity, with the
ability to set it anywhere from zero to 100 percent. Once you select a
level in manual, the unit will continue to use that exact sensitivity set­ting until you change it or revert to auto mode.

To adjust sensitivity in auto mode:

1. Press

2. The Sensitivity Control Bar appears. Press ↑ ↓ adjust sensitivity.

When it's set at the desired level, press

MENU|ENT.

EXIT.

Tip:

For quicker sensitivity adjustments, try leaving the Sensitivity
Control Bar on the screen as the chart scrolls. You can see the
changes on the screen as you press the up or down arrows. This is
handy when there's a lot of clutter in the water, and you are
matching the sensitivity to rapidly changing water conditions.

78

Sensitivity selected (left). The Sensitivity Control Bar (right).

To adjust sensitivity in manual mode:

1. First, turn off Auto Sensitivity: from the Sonar Page, press

to

AUTO SENSITIVITY|ENT.

2. Press ↑ to

SENSITIVITY|ENT and the Sensitivity Control Bar appears.

MENU|↓

Press ↓ ↑ to pick a different sensitivity setting. When it's set at the de­sired level, press

EXIT.

NOTE:

To reset Auto Sensitivity to the default setting, see the entry in this
section on Reset Options. In manual mode, Reset Options will
switch sensitivity back to Auto, its factory default setting.

Sonar Chart Mode

The default color scheme for the sonar chart is the white background,
but we offer other variations to suit your viewing preferences. The
chart can be displayed in grayscale, reverse grayscale, blue back­ground, white background, nightview, iceview or bottom color tracking.

To change the chart mode color scheme:+

1. From the Sonar Page, press

2. Press ↓ →

SONAR CHART MODE|ENT.

3. Press ↓ ↑ to Mode Name|

4. Press

EXIT|EXIT to return to the Sonar Page.

MENU|↓ to SONAR FEATURES|ENT.

ENT.

Sonar Page & Sonar Chart Display Options

The Pages Menu offers five chart display options for dual-frequency
models and four options for single-frequency models. To access them,
press

PAGES|← → to SONAR|↓ to Option Name|EXIT.

79

Pages Menu showing sonar chart display options.

Full Sonar Chart

This is the default mode used when the unit is turned on for the first
time or when it's reset to the factory defaults.

The bottom signal scrolls across the screen from right to left. Depth
scales on the right side of the screen aid in determining the depth of
targets. The line at the top of the screen represents the surface. The
bottom depth and surface temperature (if equipped with a temperature
sensor or a transducer with a temp sensor built in) show at the top left
corner of the screen.

The FasTrack™ display shows just to the right of the scale. This
changes all echoes into short horizontal bars, replicating a flasher so­nar. The zoom bar on the far right shows the area that's zoomed when
the zoom is in use.

Full Sonar Chart. The Overlay Data (depth and water temperature)

are both set to the small text size.

80

Split Zoom Sonar Chart

A split chart shows the underwater world from the surface to the bot­tom on the right side of the screen. The left side shows an enlarged ver­sion of the right side. The zoom range shows in the bottom left corner.

Split Zoom Sonar Chart. Image (left) shows the left window zoomed to

2X. The image (right) shows the left window zoomed to 4X.

Split Frequency Sonar Chart (LMS-339cDF only)

This page shows sonar data from the 50 kHz transducer on the left side
of the screen and data from the 200 kHz transducer on the right side.
All other functions and features are the same as the Full Chart page.

Split Frequency Chart (left). The Split Frequency Sonar Chart page

allows you to adjust sensitivity separately for each window (right).

You can adjust the sensitivity in each window.

To adjust sensitivity in auto mode:

1. While on the Split Frequency Chart page, press

MENU|ENT.

2. The unit asks which window (50kHz or 200kHz) you would like to

adjust. Press ← → to select the desired frequency|

ENT.

81

3. The Sensitivity Control Bar appears. Press ↓ ↑ to adjust sensitivity.

When it's set at the desired level, press

EXIT.

Digital Data/Chart

This mode shows the chart on the right side of the screen. The left side has
five digital data boxes containing: Water Depth; Water Speed (from an op­tional speed sensor); Water Distance (distance traveled or log, it also re­quires a speed sensor); Surface Water Temperature and Voltage.

Digital Data/Chart

Customize Page Displays

Every Page display option except Full Map (on the Map Page) has cus­tomizable data boxes to provide constant on-screen information.

The data available from your unit is divided into categories in the Data
Viewer menu. These categories include GPS Data, Navigation, Trip
Calculator, Time, Sonar Data and Miscellaneous Data. You can select
items from any of these categories for display in any data box.

To change the information displayed in a data box:

On the Page display you want to change, press

IZE

|ENT. A data box name flashes, indicating it is selected. Press ENT to

change the box or hit ↑ ↓, ← → to select another box, then press

MENU|↓ to CUSTOM-

ENT.

You will see a list of categories with "+" or "–" symbols next to each of
them. A category with a "+" is closed, meaning its contents are hidden.

82

Customize highlighted (left). GPS Data and Navigation categories ex-

panded in Data Viewer menu (right).

Selecting the category name and pressing ENT will open the category,
showing its data options. An open category (one with a "–" next to its
name) can be collapsed to hide its contents. Just select the category
name and press

ENT.

Open any categories that might contain data you want to display. Then
use ↓ ↑ to select a data option. With the new option highlighted, press

ENT to switch the contents of the box to the new data type, then press
EXIT. You can now select another box to change. When you are finished

with the settings, press

EXIT to return to normal operation. A Page dis-

play can show a limited number of data boxes. You can not turn them
off or add more data boxes.

Flasher page.

Flasher

The Flasher page option works like a flasher-style sonar. A circular dial
shows all returning echoes at a high screen refresh rate. It uses Color-

83

line feature to show weaker targets as lighter colors. The bottom depth
is also shown as a black bar across the outer circle.

Map With Sonar Split Screen

There is a page mode that splits the screen in half, with the map on the
left and the sonar on the right. This screen option can be found on the
Pages Menu under the Map Page category.

The full Map Page (left). Pages Menu with the Map option list (center).

The Map with Sonar split screen (right).

When the split screen is activated, you need to specify which side of the
display is the active menu. To do this, press

PAGES|PAGES. The window

with the blue title bar at the top of the screen is the active window. To
switch back, press

PAGES|PAGES again.

Sonar Simulator

This unit has a built-in simulator that lets you run it as if you were on
the water. All sonar features and functions are useable. When in
simulator mode, you will see the chart file name in the Sonar Page title
bar and a play symbol will flash on and off at the right end of the title
bar. To use the simulator:

1. From the Sonar Page, press

SONAR SIMULATOR|ENT.

MENU|MENU|↓ to SONAR SETUP|ENT|↓ to

Sonar Setup selected (left). Sonar Simulator highlighted on Sonar

Setup menu (center). Sonar Simulator turned off (right).

84

NOTE:

With Simulate Position checked, the simulator will automatically run
the GPS simulator.

2. To use the default sonar chart log stored in the unit, press

ENT|EXIT.

The recorded chart begins scrolling across the screen, just as if you
were on the water.

3. Turn off Sonar Simulator by repeating Steps 1 and 2.

"Play"
symbol
flashing

Title bar with
chart file name

Sonar Page playing a recorded sonar chart in Sonar Simulator mode.

Tip:

The Sonar Simulator can use sonar charts that you or a friend have
recorded (logged) on a MMC card. (To see how, read the entry in
this section on Log Sonar Chart Data.) To play back your own sonar
chart, make sure the MMC containing the chart is installed, then:

1. Press

2. Press ↓ to

3. Press ↓ ↑ to select chart name|

ON|ENT|EXIT.

While you're in the Sonar Simulator menu, don't forget to check
Simulate Position if you want to run the sonar and GPS simulators
simultaneously. As you review sonar logs, you can create waypoints
to mark the sites you want to revisit.

While the simulator is running, you can switch from one chart log
to another by opening the Sonar Simulator menu and using the in­structions in step 2 to select a different chart.

MENU|MENU|↓ to SONAR SETUP|ENT|↓ to SONAR SIMULATOR|ENT.

CHART USED|ENT.

ENT|↑ to SONAR SIMULATOR

Tip:

There's more than one way to play a recorded sonar chart. You can
also turn on the simulator from the MMC files list.

85

1. Press

2. Press ↓ ↑ to file name|

MENU|MENU|↓ to BROWSE MMC FILES|ENT|ENT.

ENT|↓ → to PLAY|ENT|EXIT.

Select Browse MMC Files from the Main Menu.

NOTE:

If you turn on your unit before attaching a transducer, it may enter a
demo mode. The words "demo mode" flash on the bottom of the
screen and a sonar chart plays much like the simulator. Unlike the
simulator, the demo mode is for demonstration only, and will auto­matically stop as soon as you turn on the unit with a transducer at­tached. The simulator will continue to function normally.

Stop Chart

If you are running multiple units on a boat or using this unit in a car,
there are times when you may want to turn off the sonar. This com­mand turns off the sonar and stops the chart from scrolling. Sonar re­starts automatically each time you turn on your unit.

Press

MENU|↓ to STOP CHART|ENT|EXIT.

To turn on sonar and restart the sonar chart, repeat the step above.

86

Sonar Menu with Stop Chart command selected. The box is unchecked,

indicating the chart is scrolling across the screen.

Surface Clarity

The markings extending downward from the zero line on the chart are
called surface clutter. These markings are caused by wave action, boat
wakes, temperature inversion and more.

The surface clarity control reduces or eliminates surface clutter signals
from the display. It does this by changing the sensitivity of the receiver,
decreasing it near the surface and gradually increasing it as the depth
increases.

There are three levels of surface clarity available: low, medium and
high. It can also be turned off. The default level is off.

Sonar Features menu with Surface Clarity selected.

87

To adjust the Surface Clarity level:

1. From the Sonar Page, press

2. Press ↓ to

3. Press

SURFACE CLARITY|ENT.

↓ ↑ to select clarity level, then press EXIT repeatedly.

Surface clutter

MENU|↓ to SONAR FEATURES|ENT.

In the illustration (left) Surface Clarity is turned off.

The view shows Surface Clarity set at High (right).

Transparency

Use the transparency menu to adjust the transparency of menu win­dows. A high transparency allows you to continue monitoring the
screen's display while adjusting feature settings, though the text of the
menus may fade until it is unreadable. A low transparency will usually
make menu text easier to read, at the cost of watching your display.

Experiment with this feature until you find the right level of transpar­ency for your eyes.

Transparency selected (left). Transparency slider bar (right).

88

To adjust Menu Transparency level:

Press

MENU|MENU|↓ to TRANSPARENCY|ENT. The TRANSPARENCY slider bar

appears. Press ↑ ↓ to adjust Transparency.

Upper and Lower Limits

See the entry in this section for Depth Range — Upper and Lower
Limits.

Zoom & Zoom Bar

Zooming the display is a common, fast and easy method used to enlarge
small detail, fish signals and the bottom with its associated structure.
This unit lets you zoom the display quickly and easily by pressing the
Zoom In key,

Pressing ZIN once doubles the size (2X) of all echoes on the screen.
Pressing it again quadruples the size of the echoes (4X). The zoom bar
on the far right side of the screen shows which echoes will be displayed
on the screen when the

For example, pressing the ZIN key once will enable a 2X zoom which
will show all echoes that are between the top and bottom of the 2X
zoom bar. Pressing the key again will give a 4X zoom and only the ech­oes between the top and bottom of the 4X bar will show on the screen.

Press the Zoom Out key,

ZIN.

ZIN key is pressed.

ZOUT, to return the display to the normal mode.

Sonar Page normal view (left). Same view zoomed to 2X (center). Same

view zoomed to 4X (right).

Zoom Pan

Your unit has the handy ability to quickly zoom in on any portion of the
water column with just the touch of an arrow key. The Zoom Pan feature
lets you rapidly move the zoomed area up and down to different depths.
By pointing your zoom at different portions of the chart as it scrolls, you
can get a good, close-up look at structure or cover below you. To use
Zoom Pan, switch to a manual depth Range setting and turn on 2X or
4X Zoom. Then press ↑

↓ to pan up and down the water column.

89

Notes

90

Section 5: Sonar Troubleshooting

If your unit is not working, or if you need technical help, please use the
following troubleshooting section before contacting the customer service
department. It may save you the trouble of returning your unit for re­pair. For contact information, refer to the last page, just inside the back
cover of this manual.

Unit won't turn on

1. Check the power cable's connection at the unit. Also check the wiring.

2. Make sure the power cable is wired properly. The red wire connects

to the positive battery terminal, black to negative or ground.

3. Check the fuse.

4. Measure the battery voltage at the unit's power connector. It should

be at least 10 volts. If it isn't, the wiring to the unit is defective, the
battery terminals or wiring on the terminals are corroded, or the bat­tery needs charging.

Unit freezes, locks up, or operates erratically

1. Electrical noise from the boat's motor, trolling motor, or an accessory

may be interfering with the sonar unit. Rerouting the power and trans­ducer cables away from other electrical wiring on the boat may help.
Route the sonar unit's power cable directly to the battery instead of
through a fuse block or ignition switch

2. Inspect the transducer cable for breaks, cuts, or pinched wires.

3. Check the transducer and power connector. Make sure it's securely

plugged in to the unit.

Weak bottom echo, digital readings erratic, or no fish signals

1. Make sure the transducer is pointing straight down. Clean the face of

the transducer. Oil, dirt and fuel can cause a film to form on the trans­ducer, reducing its effectiveness. If the transducer is mounted inside the
hull, be sure it is shooting through only one layer of fiberglass and that it
is securely bonded to the hull. When attaching a transducer to the inside
of a hull, ONLY use the epoxy available from LEI (order information is
inside the back cover). Do NOT use RTV silicone rubber adhesive or any
other type of epoxy. The LEI epoxy is specially formulated so that it will
cure properly for shoot-through applications.

2. Electrical noise from the boat's motor can interfere with the sonar.

This causes the sonar to automatically increase its discrimination or
noise rejection feature. This can cause the unit to eliminate weaker
signals such as fish or even structure from the display.

91

3. The water may be deeper than the sonar's ability to find the bottom.

If the sonar can't find the bottom signal while it's in the automatic
mode, the digital sonar display will flash continuously. It may change
the range to limits far greater than the water you are in. If this hap­pens, place the unit in the manual mode, then change the range to a
realistic one, (for example, 0-100 feet) and increase the sensitivity. As
you move into shallower water, a bottom signal should appear.

4. Check the battery voltage. If the voltage drops, the unit's transmitter

power also drops, reducing its ability to find the bottom or targets.

Bottom echo disappears at high speeds or erratic digital read­ing or weak bottom echo while boat is moving

1. The transducer may be in turbulent water. It must be mounted in a

smooth flow of water in order for the sonar to work at all boat speeds. Air
bubbles in the water disrupt the sonar signals, interfering with its ability
to find the bottom or other targets. The technical term for this is cavitation.

2. Electrical noise from the boat's motor can interfere with the sonar.

This causes the sonar to automatically increase its discrimination or
noise rejection feature. This can cause the unit to eliminate weaker
signals such as fish or even structure from the display. Try using resis­tor spark plugs or routing the sonar unit's power and transducer cables
away from other electrical wiring on the boat.

No fish arches when the Fish I.D. feature is off

1. Make sure the transducer is pointing straight down. This is the most

common problem if a partial arch is displayed.

2. The sensitivity may not be high enough. In order for the unit to dis-

play a fish arch, it has to be able to receive the fish's echo from the time
it enters the cone until it leaves. If the sensitivity is not high enough,
the unit shows the fish only when it is in the center of the cone.

3. Use the Zoom feature. It is much easier to display fish arches when

zoomed in on a small range of water than a large one. For example, you
will have much better luck seeing fish arches with a 30 to 60 foot range
than a 0 to 60 foot range. This enlarges the targets, allowing the dis­play to show much more detail.

4. The boat must be moving at a slow trolling speed to see fish arches.

If the boat is motionless, fish stay in the cone, showing on the screen as
straight horizontal lines.

NOISE

A major cause of sonar problems is electrical noise. This usually ap­pears on the sonar's display as random patterns of dots or lines. In se­vere cases, it can completely cover the screen with black dots, or cause
the unit to operate erratically, or not at all.

92