Lowrance electronic LMS-320, LMS-320DF User Manual

www.lowrance.com

Pub. 988-0105-971

LMS-320, LMS-320DF

Fish-finding Sonar & Mapping GPS

Operation Instructions

Copyright © 2002 Lowrance Electronics, Inc.

All rights reserved.

Lowrance

®

is a registered trademark of Lowrance Electronics, Inc.

MapCreate is a trademark of Lowrance Electronics, Inc.

Marine-Tex is a trademark of Illinois Tool Works Inc.

Navionics



is a registered trademark of Navionics, Inc.

Points of Interest Data in this unit are by infoUSA,
copyright  2001-2002, All Rights Reserved. infoUSA is a
trademark of infoUSA, Inc.

eXitSource Database, copyright  2001-2002 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-320 shown. Other models covered in the manual are similar.

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

Sec. 1: Read Me First! ...............................................................1

Capabilities and Specifications: LMS-320 and LMS-320DF ........ 3

How LMS-320 Sonar Works ......................................................... 5

How LMS-320 GPS Works ........................................................... 6

Introduction to GPS and WAAS................................................... 8

How to Use this Manual: Typographical Conventions.............. 10

Sec. 2: Installation & Accessories ........................................ 13

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

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

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

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

Transom Transducer Assembly and Mounting .....................16

Trolling Motor Bracket Installation....................................... 22

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

Shoot-Thru-Hull Preparation................................................. 23

Shoot-Thru-Hull Installation ................................................. 25

Sensor Chart ............................................................................... 27

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

GPS Antenna/Receiver Module .................................................. 29

Power Connections...................................................................... 30

NMEA/DGPS Cable Connections............................................... 31

Mounting the Unit: Bracket, in-Dash or Portable .................... 33

Bracket Installation................................................................ 34

in-Dash Installation................................................................ 36

Portable Installation............................................................... 36

MMC or SDC Memory Card Installation................................... 37

Other Accessories........................................................................ 38

Sec. 3: Basic Sonar Operation............................................... 41

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

Power/Lights on and Off............................................................. 42

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

Pages ........................................................................................... 44

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

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

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

Sonar Page .............................................................................. 46

LMS-320 Series Sonar Quick Reference.................................... 49

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

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

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

Sec. 4: Sonar Options & Other Features ............................55

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

i

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

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

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

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

Calibrate Speed........................................................................... 58

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

Depth Cursor............................................................................... 60

Depth Range - Automatic ........................................................... 60

Depth Range - Manual................................................................ 61

Depth Range - Upper and Lower Limits ................................... 61

FasTrack .................................................................................. 63

Fish I.D. (Fish Symbols & Depths) ......................................... 63

FishTrack ................................................................................. 65

FishReveal ............................................................................... 66

Frequency (Change Transducer Frequency) .............................68

Grayline



..................................................................................... 69

HyperScroll .............................................................................. 71

Log Sonar Chart Data ................................................................ 71

Noise Rejection............................................................................ 71

Overlay Data ............................................................................... 71

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

Reset Options .............................................................................. 75

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

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

Sensitivity & Auto Sensitivity.................................................... 77

Sonar Color Mode........................................................................ 79

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

Full Sonar Chart ..................................................................... 79

Split Zoom Sonar Chart.......................................................... 80

Split Frequency Sonar Chart ................................................. 81

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

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

Map with Sonar Split Screen ................................................. 84

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

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

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

Upper and Lower Limits ............................................................ 88

Zoom & Zoom Bar ....................................................................... 88

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

Sec. 5: Sonar Troubleshooting.............................................. 91

Sec. 6: Basic GPS Operations................................................ 95

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

Power/Lights (Turn Unit On and Off) ....................................... 96

ii

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

Pages ........................................................................................... 98

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

Satellite Status Page .............................................................. 99

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

Map Page............................................................................... 102

LMS-320 GPS Quick Reference................................................ 107

Find your Current Position ...................................................... 108

Moving around the Map: Zoom & Cursor Arrow Keys............ 108

Selecting any Map Item with the Cursor ................................ 109

Searching................................................................................... 109

Set a Waypoint.......................................................................... 111

Create Waypoint at Current Position .............................. 112

Create Waypoint on Map .................................................. 113

Create Waypoint by Entering a Position ......................... 113

Navigate to a Waypoint ............................................................ 113

Set Man Overboard (MOB) Waypoint...................................... 114

Navigate Back to MOB Waypoint ............................................ 114

Navigate to Cursor Position on Map........................................ 115

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

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

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

Navigating Trails...................................................................... 119

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

Navigate a Trail (Forward)................................................... 120

Navigate a Back Trail (Backtrack, or Reverse) ................... 122

Transfer Custom Maps and GPS Data Files ........................... 122

Custom Maps:........................................................................ 122

GPS Data Files:..................................................................... 123

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

Sec. 7: Advanced GPS Operations .....................................127

Find Distance from Current Position to Another Location .... 127

Find Distance from Point to Point ........................................... 127

Icons........................................................................................... 128

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

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

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

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

Routes........................................................................................ 130

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

Delete a Route ....................................................................... 133

Edit a Route .......................................................................... 133

Navigate a Route................................................................... 134

iii

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 (Name, Symbol, Position) ......................... 137

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

Set a Waypoint by Average Position .................................... 138

Set a Waypoint by Projecting a Position.............................. 138

Sec. 8: System & GPS Setup Options.................................141

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

Auto Satellite Search................................................................ 142

Check MMC Files and Storage Space...................................... 143

Communications Port Configuration ....................................... 143

Configure DGPS........................................................................ 144

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

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

Map Fix.................................................................................. 146

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

DGPS Status ............................................................................. 148

GPS Simulator .......................................................................... 148

Hide GPS Features ................................................................... 150

Initialize GPS............................................................................ 150

Map Auto Zoom......................................................................... 150

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

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

Pop-Up Map Info................................................................... 151

Map Boundaries .................................................................... 151

Fill Land Gray....................................................................... 152

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

Map Datum Selection ............................................................... 152

Map Detail Category Selection................................................. 153

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

Navionics



Charts..................................................................... 155

iv

Display a Navionics Chart:................................................... 155

Port Information ...................................................................156

View Port Services Information: ..........................................156

Tidal Current Information ................................................... 157

to View Tidal Current Information: ..................................... 158

Tide Information ................................................................... 159

View Tide Information:......................................................... 159

Pop-Up Help.............................................................................. 161

Position Pinning........................................................................ 161

Reset Options ............................................................................ 162

Require DGPS ........................................................................... 162

Screen Contrast and Brightness .............................................. 163

Set Language ............................................................................ 164

Set Local Time .......................................................................... 164

Show WAAS Alarm................................................................... 165

Software Version Information.................................................. 165

Sounds and Alarm Sound Styles.............................................. 166

Track Smoothing....................................................................... 166

Trail Options ............................................................................. 167

Delete All Trails .................................................................... 167

Flash Trails on Screen Option.............................................. 167

Update Trail Option.............................................................. 167

Delete Trail ........................................................................... 168

New Trail............................................................................... 168

Trail Visible/Invisible and Other Trail Options .................. 169

Units of Measure....................................................................... 169

Sec. 9: Searching....................................................................171

Find Addresses.......................................................................... 171

Find any Item Selected by Map Cursor ................................... 174

Find Interstate Highway Exits ................................................ 175

Find Map Places or Points of Interest (POI) ........................... 177

Find Streets or Intersections.................................................... 179

Find Waypoints......................................................................... 182

Sec. 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. Here's how:

The manual is organized into 10 sections. This first section is an intro­duction to the LMS-320 or LMS-320DF, 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, the transducer and the GPS
antenna module. 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 LMS-320 series sonar, right out of the box. This section fea­tures a one-page Sonar Quick Reference. (If you've already jumped

ahead and figured 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 with your LMS-320!)

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 the LMS-320 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 107.

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 LMS-320's many advanced
navigation features. That brings us to Section 7, Advanced GPS Opera-
tions. This section contains the rest of LMS-320's GPS command func­tions, organized in alphabetical order.

When you come to a GPS menu command on the LMS-320 screen, you can
look it up in the manual by skimming over the table of contents, just flip­ping through Section 6 or scanning through the command portion of Sec­tion 7.

LMS-320 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 LMS-320'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 LMS-320 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.

2

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 con­tains. 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 LMS-320
can store, skip ahead to important information on how LMS-320 sonar
works, on page 5. (Background on GPS begins on page 6.)

Capabilities and Specifications: LMS-320 and LMS-320DF

General

Display:............................ 5.0" (12.7 cm) diagonal high contrast Film

SuperTwist LCD; programmable to viewing
preference.

Resolution:...................... 320 pixel x 320 pixel resolution; 102,400 total

pixels; 10-level gray scale definition.

Backlighting:.................. Incandescent backlit screen with multiple

lighting levels; backlit keypad.

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).

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-320DF: 50/200 kHz.

LMS-320: 200 kHz.

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



transducer with

built-in temperature sensor is packed with the
LMS-320DF. It has 35°/12° cone angles. A sin­gle-frequency Skimmer transducer with built­in temperature sensor is packed with the
LMS-320. It has a 20° cone angle. Transducers
operate at speeds up to 70 mph (61 kts).

Transmitter: ................... 3,000 watts peak-to-peak/375 watts RMS.

3

Sonar sounding

depth capability: ........... LMS-320DF: 2,500 feet/762 meters.

LMS-320: 1,000 feet/305 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 256 MB 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-320DF.)

GPS

Receiver/antenna: ......... External; LGC-12w 12 parallel channel

GPS/WAAS; DGPS beacon receiver optional.

Recording:........................ MMC & SD memory cards for recording GPS

trip details and displaying charts or custom
maps.

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.

Custom mapping: .......... MapCreate version 6 software optional;

Navionics



charts (XL charts or HotMaps)

on MMC cards optional.

Mapping memory: ......... Up to 256 MB on one MMC (or SD) card.

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

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

4

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:.................... 37 ranges; 0.05 to 4,000 miles.

NOTE:

The above memory capacities refer only to LMS-320'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 LMS-320 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
ogy developed during World War II for tracking enemy submarines.
(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.

vigation and Ranging, a technol-

5

Your LMS-320 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 LMS-320 GPS Works

You'll navigate faster and easier if you understand how the LMS-320
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 on 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 LMS-320 as a small but powerful computer. (But
don't worry — we made the LMS-320 series easy to use, so you don't
need to be a computer expert to find your way!) The unit includes a
keypad and a screen with menus so you can tell LMS-320 what to do.
The screen also lets LMS-320 show your location on a moving map, as
well as point the way to your destination.

This gimbal-mounted unit uses an external antenna/receiver module,
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. (It will also listen in to the
WAAS satellites in orbit, but more about that in the upcoming segment
introducing you to GPS and WAAS.)

Your LMS-320 listens to signals from as many satellites as it can "see"
above the horizon, eliminates the weakest signals, then computes its
location in relation to those satellites. Once LMS-320 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 LMS-320 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

6

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 LMS-320'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. Like any
computer file, these GPS Data Files (file format *.usr) can be shared
between LMS-320s, other Lowrance GPS or sonar/GPS units, even per­sonal computers.

LMS-320 has one more thing in common with a personal computer.
Just as computers have a floppy disk drive for storing and exchanging
files, the LMS-320 has a slot for an MMC (MultiMedia Card) or SDC
(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 128 MB in size. (Compare that to a floppy disk's 1.44 MB
capacity!) LMS-320 uses all that MMC space for two key GPS purposes.
(The MMC is also used to record sonar logs…see page 6.)

First, you can backup your onboard GPS Data Files by copying them to
the MMC. Since the MMC is 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
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 LMS-320's
memory. (NOTE: No matter where they come from, GPS Data Files
must be loaded from the MMC into memory before LMS-320 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 MapCre­ate software. These MapCreate custom maps contain much greater de­tail than the basic background map. These Custom Map Files (file
format *.lcm) can also be shared between LMS-320s, other Lowrance
GPS or sonar/GPS units and personal computers. (For example, the
exact same MMC, custom map files and GPS data files can be used in­terchangeably between your gimbal-mounted LMS-320 and the hand­held iFINDER GPS receiver.)

7

LMS-320 automatically reads Custom Map Files directly from the
MMC or SDC. 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 LMS-320 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 10. 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. 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.

8

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

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.

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, LMS-320 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 for
LMS-320 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 simply be more "wandering" of the
data shown on the display.

GPS is plenty accurate for route navigation, but the U.S. Federal Avia­tion Administration has special needs for aircraft traffic control that go
beyond basic GPS. The FAA has a plan under way to boost GPS per­formance even further with its Wide Area Augmentation System, or
WAAS. This GPS add-on will include a time control element that will
help airliners fly closer together while avoiding collisions. In addition to
carefully spacing airplanes along travel corridors, WAAS will eventu­ally make instrument landings and takeoffs more accurate as it re­places existing aviation navigation systems.

Non aviators can use WAAS signals to make their GPS navigation even
more accurate. Your LMS-320 receives both GPS and WAAS signals.
However, WAAS has some limits you should know about.

9

First, the U.S. government has not completed construction of the WAAS
system, so it is not yet fully operational. The ground stations are in
place, but only a few of the needed WAAS satellites have been launched.

WAAS can boost 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 man-made
structures frequently 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.

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:

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

.

MENU

Menu Commands

A menu command or a menu option will appear in small capital letters, in

and the "Menu" key is shown as

ENT

10

a bold sans serif type like this:

OUTE PLANNING

R

. 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 LMS-320 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

MENU|MENU

AVIGATE

N

|↓ to

|

ENT

MY T

.

RAILS

|

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. Now, begin moving and
follow your LMS-320.

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."

11

Notes

12

Section 2:

Installation & Accessories

Preparations

You can install the sonar and GPS systems 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 vehicle or vessel!

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

2. Determine the approximate location for the transducer and its cable
route.

3. Determine the approximate location for the GPS antenna module
and its cable route.

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

5. Install the transducer and route the transducer cable to the so­nar/GPS unit.

6. Install the GPS antenna and route the antenna cable to the so­nar/GPS unit.

7. Install the power cable and route it to the sonar/GPS unit.

8. Mount the sonar/GPS unit.

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 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 mounting positions is right for your boat. Use
extreme care if mounting the transducer inside the hull, because once it
is epoxied into position, the transducer usually cannot be removed.

Remember, the transducer installation 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" drill bit. A transom mount requires use of a high quality,
marine grade above- or below-waterline caulking compound. 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: none.

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.

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. Supplies: 100 grit sandpaper, good quality
epoxy adhesive.

Selecting a Transducer Location

1. The transducer must be placed in a location that has a smooth flow of

water at all times. If the transducer is to be mounted inside the hull,
then the chosen location must be in the water at all times. If the
transducer is not placed in a smooth flow of water, interference
caused by bubbles and turbulence will show on the 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

14

at speeds faster than 35 mph. Typically, a good location on alumi­num boats is between the ribs closest to the engine.

2. The transducer should be installed with its face pointing straight

down, if possible.

3. If the transducer is mounted on the transom, make sure it doesn't inter-

fere 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.

4. 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
prevent the transducer from
entering the boat if it is
knocked off at high speed.

Good location

Poor location

Good
location

Poor angle

Good and poor transducer locations.

Good location

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.

15

Transducer
centerline

Align transducer centerline with hull bottom.

Transom

Hull bottom

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 wish, 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

Typically, shoot-thru-hull installations give excellent high speed opera­tion and good to excellent depth capability. There is no possibility of
damage from floating objects. It can't be knocked off when docking or
loading on the trailer.

However, 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. This can be a problem on some hulls that sit with the bow high
when at rest or at slow trolling speeds. Follow the procedure listed in
the shoot-thru-hull installation section at the end of this lesson 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.

16

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.

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

Transducer bracket

Insert and align ratchets.

17

Transducer

bracket

Transducer

Ratchet

Add ratchets to bracket and transducer.

Ratchet

2. Aligning the transducer on the transom.

A. One-piece bracket: Slide the transducer between the two ratch-

ets. 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

Insert bolt and check transducer position on transom.

18

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.

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.

Bolt

Flat washer

Assemble transducer and bracket.

Lock washer

Nut

Flat washer

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

Rubber
washers

Assemble transducer and bracket.

washer

Metal washer

Bolt

19

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).

Transom

Transom

Position transducer mount on transom and mark mounting holes.

Side view shown at left and seen from above at 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 at left and seen from above at right.

20

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 caulking 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

Flat-bottom hull Deep-"vee" hull

Align transducer centerline with hull bottom and attach transducer to

transom. Rear view of dual-frequency Skimmer shown.

6. Route the transducer cable through or over the transom to the sonar

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 be 1".

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.

21

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.)

TMB-S bracket

Bolt

Internal tooth washer

Nut

Flat washer

Attach motor mounting bracket to transducer.

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.

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.

22

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.

Partial fish arches

Transducer aimed

too far back

Transducer aimed

too far forward

Full fish arch

Proper transducer angle

Transducer angles and their effects on fish arches.

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.

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

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

23

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.

Fill with epoxy

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, 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.

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.

To choose the proper location for thru-hull mounting, anchor the boat in
60 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. Adjust the sensitivity and range controls until a sec­ond bottom echo is seen on the display. (You will need to turn off both
automatic and ASP.) Don't touch the controls once they've been set.

Next, take the transducer out of the water and place it in the water in
the sump of the boat. Observe the sonar signal to see if there is a no­ticeable decrease in sensitivity. The second bottom signal may disap­pear and the bottom signal may decrease in intensity.

Move the transducer around to find the best location. If the sensitivity
control must be increased greatly to compensate, then the transducer
should be mounted on the outside of the hull. If not, then mark the lo-

24

cation that shot through the hull the best and follow the instructions on
the following pages for a shoot-thru-hull mounting.

Transducer location

(high speed)

Shoot-thru-hull transducer locations for

high speed or trolling speed operation.

Transducer location

(trolling speed)

Shoot-thru-hull Installation

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 surface of the hull must be flat so the entire
transducer face is in contact with the hull prior to bonding.

Spread epoxy here

Sand this surface

Epoxy transducer to hull.

2. Follow the instructions on the epoxy package and mix it thoroughly.

Do not mix it too fast, because it will cause bubbles to form in the ep­oxy. Apply a small amount on the face of the transducer as shown
above, then spread a small amount onto the sanded area on the hull.

25

Place the transducer into the epoxy, twisting and turning it to force
any air bubbles out from under the transducer face. The face of the
transducer should be parallel with the hull, with a minimum amount
of epoxy between the hull and transducer. After the epoxy dries,
route the cable to the sonar unit.

Speed/Temperature Sensors

This unit accepts up to three temperature sensors which can monitor
surface water, live well, air and virtually any other temperature. If you
want to use more than one temperature sensor or a speed sensor, you
must purchase the optional MY-4X adapter cable. You also need to be
careful when purchasing the temperature sensors, because each tem­perature sensor has its own fixed electronic "address." The sensors are
labeled "Water," "T-2" (or Temp-2) and "T-3" (or Temp-3).

The first "Water" temperature sensor is built into the transducer. This
is the sensor that measures surface water temperature. If you want two
(or more) temperature readings from other locations, you'll need to use
the proper sensors. For example, you can't use two additional T-3 sen­sors. The sensors that fit this unit are:

• TS-1X This sensor will over-ride the temperature sensor

built into the transducer and over-ride the tem­perature sensor in a ST-TGY combination sen­sor. (This sensor is not recommended.)

• TS-2X One sensor for "T-2" temperature display.

• TS-3X One sensor for "T-3" temperature display.

• SP-X One speed sensor for "Speed" display.

• ST-TGY This combination sensor will provide speed and

temperature readings, but the temperature
reading will be displayed as the "Water" tem­perature because it will over-ride the tempera­ture sensor in the transducer. (This sensor is
not recommended.)

See the wiring diagram on the following page for temperature and
speed sensor combinations.

26

MY-4X
Cable

Three-temperature
sensor installation

Sensor Chart

LMS-320
rear view

Temperature
sensor built into
transducer

Two-temperature
sensor installation

TS-2X
temperature sensor

TS-3X
temperature sensor

Three-temperature sensor
installation with speed

SP-X speed sensor

27

Optional Speed Sensor Installation

All the units in this series can display speed and distance traveled, but
only the LMS-320DF comes packed with a speed sensor. If you wish 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 caulking compound.

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
caulking compound 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 caulking 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 in-line con­nector on the MY-4X adapter cable. If you have any questions concern­ing the installation of the sensor, please contact your local boat dealer.

GPS Antenna/Receiver Module

The LMS-320 series package includes the LGC-12w GPS module. This
device contains the unit's external antenna and receiver for GPS and
WAAS signals. The antenna/receiver module comes with a 25-foot ex­tension cable. This module can be mounted on a flat surface or pole, or
a magnet is included for temporary mounting on any ferrous surface.
(The LGC-12s GPS module sold with earlier Lowrance equipment will
work with your unit, but it will not receive WAAS signals.)

LGC-12 Module, bottom view (left) and top view (right).

29

You need to select an antenna installation location that has a clear, un­obstructed view of the sky. After the module is installed, route the cable
to the LMS-320, plug it in the center socket on the back and your sys­tem is ready to use. See the module's instruction sheet, publication part
number 988-0147-39, for complete installation directions.

In an automobile, you may achieve good results by simply placing the
external antenna on the top of the dash, at the base of the windshield.
A piece of the rubber non-skid shelf liner material available in recrea­tional vehicle supply stores will help hold the antenna in place. This
may not work well if you have a cab-over design pickup truck camper or
motor home. If dashboard reception is poor, simply relocate the an­tenna module elsewhere on the vehicle for a clearer view of the sky.

Power Connections

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

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. 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.

30

p

To unit

Power connections for the LMS-320 series sonar/GPS unit.

Black wire

Data wires

12 volt

battery

Red wire with

3 am

fuse

CAUTION:

Do not use this product without a 3-amp fuse wired into the power
cable! 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.

An optional 8-foot, CA-4 external power cable with a cigarette lighter
adapter is available from Lowrance.

NMEA/DGPS Cable Connections

NMEA is a standard communications format for marine electronic
equipment. For example, an autopilot can connect to the NMEA inter­face on the LMS-320 and receive positioning information. The LMS-320
can exchange information with any device that transmits or receives
NMEA 0183 data.

DGPS is an acronym for the Differential Global Positioning System.
DGPS supplements and boosts the accuracy of basic GPS. DGPS was
developed by the U.S. Coast Guard, which is responsible for the sys­tem's operation in the United States. Since it's creation, DGPS has be­come the international maritime standard for marine navigation.

The most popular DGPS system relies on a grid of ground-based trans­mitters that send correction signals to DGPS receivers. These in turn,
connect to the GPS receiver (such as the LMS-320). Lowrance offers an
optional DGPS receiver for your unit.

31

See the diagrams on the following page for general wiring connections.
Read your other product’s owner’s manual for more wiring information.

NMEA/DGPS Wiring

To exchange NMEA or DGPS data, the LMS-320 has one NMEA 0183
version 2.0 communication port. Com port one (Com-1) can be used to
receive NMEA format GPS data or DGPS data. The com port can also
transmit NMEA format GPS data to another device.

The three wires for the com port are combined with the two power
wires to form the power/data cable (see the drawing on page 33). Com-1
uses the yellow wire to transmit, the orange wire to receive and the
shield wire for signal ground.

Com-1

To LMS-320

Com-1

To LMS-320

Com-1

To LMS-320

Com-1 wiring to transmit NMEA position information

Yellow (Transmit)

Orange (Receive)

Shield (Ground)

Com-1 wiring to receive DGPS position information

from a DGPS receiver.

Orange (Receive)

Shield (Ground)

Com-1 wiring to receive NMEA position information

from some other GPS receiver.

Yellow (Transmit)

Shield (Ground)

to another NMEA-compatible device.

Receive

Transmit

Ground

NMEA Transmit

Ground

NMEA Receive

Ground

GPS Receiver

To DGPS
Receiver

To Other

To Other

Device

32

LMS-320,
rear view

GPS socket

Power/Data socket

Com port

data wires

(three)

Power wires

(two)

GPS

antenna

module

LMS-320 cable connections.

Sonar socket

Transducer

Mounting the Unit: Bracket, In-Dash or Portable

You can install the LMS-320 on the top of a dash with the supplied
gimbal bracket. It can also be installed in the dash or 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, which can be used on the dash or overhead
mounting positions. Installation instructions are supplied with the
R-A-M mounting kits.



bracket mounting system. This converts the unit's gimbal

33

Optional R-A-M mounting system.

Bracket Installation

Mount the unit in any convenient location, provided there is clearance
behind the unit when it's tilted for the best viewing angle. You should
also make sure there is enough room behind the unit to attach the
power, transducer and GPS antenna/receiver module cables. (A draw­ing on the next page shows the dimensions of a gimbal-mounted LMS­320 unit.)

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. Orient the bracket so the arms slope toward

the front of your unit.

34

Drill a 1-inch (25.4 mm) hole in the dash for the power, transducer and
antenna 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, however, 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 LMS-320

sonar/GPS unit when mounted on gimbal bracket.

157.9
[6.22]

56.9
[2.24]

After drilling the hole, pass the transducer connector up through the
hole from under the dash, followed by antenna connector. Pass the
power cable's bare-wire end down though the hole from the top.

If you wish, you can fill in the hole around the cables with a good ma­rine caulking compound. (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, thus 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.

35

In-Dash Installation

You can mount the unit in the dash with an optional FM-5 In-Dash
Adapter Kit. The kit includes mounting hardware, a template for cut­ting the hole and an instruction sheet, part 988-0147-43.

146.5
[5.76]

Top

R 7.9
[0.31]

In-Dash

Template

Millimeters

[Inches]

ALWAYS VERIFY DIMENSIONS

113.5
[4.46]

In-dash mounting template for LMS-320 sonar/GPS unit, showing

dimensions. NOTE: The figure above is not printed to scale. A scaled

template (FM-5 In-Dash Adapter Kit instructions) is available for free

download from our web site, www.lowrance.com.

Portable Installation

Like many Lowrance products, the LMS-320 is capable of portable op­eration by using the optional PPP-11 portable power pack. The power
pack, the magnet-equipped antenna module and an optional portable
transducer expand the uses for your sonar/GPS unit. The PPP-11
makes it easy to transfer your unit from a boat to a car, recreational
vehicle, airplane or other vehicle without drilling and mounting a sec­ond bracket. You can use your unit in your own car or boat, then take it
along when riding in a friend's vehicle that's not equipped with sonar or
GPS. (Or use it as a second sonar, one for each fisherman!)

The PPP-11 Portable Power Pack can be used with eight "D" cell alka­line batteries or an optional sealed, rechargeable battery. For set-up
directions, refer to the pack's instruction sheet, part 988-0147-46.

36

"D" cell battery

Install batteries in power pack battery adapter.

MMC or SDC Memory Card Installation

Your LMS-320 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 or SDC) to store data.

NOTE:

Throughout this manual, we will use the term MMC, but just re­member that your unit can use an MMC or SDC 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 and 64 MB. SD cards were available in capacities of
8 MB, 16 MB, 32 MB, 64 MB, 128 and 256 MB.

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.

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.

37

MMC groove for card removal

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. Use a thumbnail or fingernail to grab the groove in the bottom of the
MMC. See the figure above for the groove location.

3. Drag the MMC from the slot.

To add an MMC or SDC

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 LMS-320 accessories include MMC cards, MMC card readers and
MapCreate™ 6 custom mapping software for your computer. MMC card
readers are available in USB and parallel port versions.

Two switch boxes are available for this unit. The SB-7X transducer
switch box switches two transducers to one sonar unit. The SB-8X trans­ducer switch box switches two sonar units to one transducer.

If these accessories are not available from your dealer, see the acces­sory ordering information on the inside back cover of this manual. Visit
our web site for a complete listing of all the available accessories for
your unit.

38

MapCreate™ 6 CD-ROM, left; MMC card reader for USB ports, right.

Now that you have your unit installed, move on to Section 3, Basic So­nar Operations. There, we'll present a series of step-by-step tutorials to

teach you the basics of LMS-320 sonar operation.

NOTE:

When you first turn the unit on, the Map Page appears. If you'd
rather start learning about GPS operation first, turn over to Sec­tion 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.)

Face Cover

Your LMS-320 comes with a white protective cover that snaps on and
off the front of the unit. This cover is intended for use when your unit
and the vehicle it's mounted in are 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.

39

Notes

40

Section 3: Basic Sonar Operation

This section addresses the unit's most basic sonar operations. The in­structions presented in Sec. 3 follow a chronological order. Sec. 4, Sonar
Options & Other Features, will discuss other more advanced functions
and utilities. Material in Sec. 4 is arranged in alphabetical order.

Before you turn on the LMS-320, it's 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

2

3

5

MMC slot access door

LMS-320 series sonar/GPS unit, front view, showing map with sonar

split screen, keyboard and access door for the MMC slot.

9

7

6

1

1. PWR/LIGHT (Power & Light) – The PWR key turns the unit on and
off and activates the backlight.

2. PAGES – Pressing this and the ← → arrow keys switches the unit
between the four different page screens. (Satellite Status Page, Naviga­tion Page, Map Page and Sonar Page.) Each page represents one of the
unit's major operation modes.

41

3. MENU – Press this key to show the menus and submenus, which
allow you to select a command or adjust a feature. This also accesses
search functions for streets, intersections, addresses and highway exits.

4. ARROW KEYS – These keys are used to navigate through the
menus, make menu selections, move the map and sonar chart cursors
and enter data.

5. ENT/ICONS (Enter & Icons) – This key allows you to save data, ac­cept values or execute menu commands. It is also used to create event
marker icons.

6. EXIT – The Exit key lets you return to the previous screen, clear
data or erase a menu.

7. WPT – (Waypoint) The Waypoint key is used to save and recall way­points, search for waypoints and access the waypoint list. It also
launches the Point-of-Interest (POI) search menus and is involved in
some navigation functions.

8. ZOUT – (Zoom Out) – This key lets you zoom the screen out. On the
Sonar Page, this key returns you to a full sonar chart display, showing
the entire water column from surface to bottom. On the Map Page, this
lets you see a larger geographic area on the map. Less detail is seen as
you zoom out.

9. ZIN – (Zoom In) – This key lets you zoom the screen in. On the Sonar
Page, this key 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
displayed first. To switch to the Sonar Page, press

To turn on the backlight, press
levels to select from. Repeatedly pressing
backlight settings and turn off the backlight.

Turn off the unit by pressing and holding the

. As the unit powers up, the Map Page is

PWR

PAGES

again. The unit has three backlight

PWR

will cycle through the

PWR

key for 3 seconds.

PWR

|→|

EXIT

.

Main Menu

The LMS-320 has a Main Menu, which contains some function com­mands and some setup option commands. The instructions in this sec­tion will deal only with sonar functions, the basic commands that make
LMS-320 show sonar signals on your screen. LMS-320 will work fine
right out of the box with the factory default settings. But, if you want to

42

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

MENU|MENU

display, press

EXIT

. To clear the menu screen and return to the page

. (Remember, our text style for "

MENU|MENU

" means

"press the Menu key twice." See a full explanation of our instruction
text formatting on page 10, Instructions = Menu Sequences.)

Main Menu.

The Main Menu commands and their functions are:

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

Sounds command: enables or disables the sounds for key strokes and
alarms and sets the alarm style.

Alarms command: turns GPS alarms on or off and changes alarm
thresholds.

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

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

to navigate or backtrack a trail.

Cancel Navigation command: turns off the various navigation com­mands. Used to stop navigating after you have reached your destina­tion waypoint, Point of Interest or map cursor location; or after you
reach the end of a route or trail.

Sonar Setup command: sets various sonar options.

GPS Setup command: sets various GPS receiver options.

43

System Setup command: sets general configuration options.

Sun/Moon Calculations command: finds the rising and setting time

of the sun and the moon.

Trip Calculator command: shows trip status and statistics.

Timers command: controls the up timer, down timer and alarm clock

settings.

Browse MMC Files command: this allows you to view the installed
MMC card and the files it contains.

Pages

The unit has four Page displays that represent the four major operating
modes. They are the Satellite Status Page, the Navigation Page, the Map
Page and Sonar Page. They are accessed by pressing the

PAGES

then using → or ← to select a Page. (Clear the Pages Menu by pressing

.)

EXIT

key,

Pages Menu, showing some Sonar display options.

Satellite Status Page

The Satellite Status Page provides detailed information on the status of
LMS-320's satellite lock-on and position acquisition. To get to the Sat­ellite Status Page: Press the

. (Clear the Pages Menu by pressing

S

TATUS

PAGES

key, then use → or ← to select

.)

EXIT

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 that
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!

44

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

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

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

| → or ← to

N

AVIGATION

|

EXIT

.

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

Navigation Page, recording a trail, traveling southwest.

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're traveling.

45

Map Page, showing position on Bull Shoals Lake, Arkansas. At left is

the full map option. At right, map with sonar option.

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
to

|

EXIT

.

M

AP

PAGES

| → or ←

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
lect

. (Clear the Pages Menu by pressing

S

ONAR

PAGES

key, then use → or ← to se-

.) The Pages Menu

EXIT

also offers five chart display options under the Sonar Page category. To
access them, press

PAGES

|← or→ to

|↓ to Option Name|

S

ONAR

EXIT

.

The Sonar Page also 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

.

46

At left, Pages Menu, showing sonar chart display option commands.

At right, Sonar Page in full sonar chart display mode.

Sonar chart display options (from left) split zoom and split frequency.

Sonar chart display options (from left) digital data and flasher.

47

Sonar Page Menu. Most of these functions are discussed in Sec. 4.

Digital data
overlay
(depth &
temperature)

Fish arches

Structure

Surface signal

Bottom signal

Sonar Page, showing 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. Your unit also includes several special sonar fea­tures and options that can help you better interpret the underwater
scene.

We'll discuss all of those features and options in Sec. 4, but to show you
how easy the LMS-320 is to operate, the following page contains a sim­plified, 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

LMS-320 Series 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 LMS-320, press and release

PWR

key.

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

|← or → 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

ZOUT

.

ZIN

.

7. Watch the display for the appearance of fish arches. When you see
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 arches with the
depth scale on the right side of the screen, or get a more accurate
measure with the Depth Cursor. Press

MENU

|↓ to

D

EPTH CURSOR

|

ENT

Press ↓ to align the cursor line with the fish arch. The exact depth ap­pears in a box at the right end of the cursor line. To clear the cursor,
press

EXIT

.

.

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

10. To turn off LMS-320, press and hold

key for three seconds.

PWR

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're 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 you change the sensitivity setting, you can see the difference on the chart
as it scrolls.

Fig. 1

Fig. 2

Fig. 3

Fig. 4

These figures show results of different sensitivity levels on the same

location. Fig. 1: Sensitivity at 88 percent, determined by Auto Sensitiv-

ity. Typical of full auto mode. Fig. 2: Sensitivity set at 75 percent. Fig.

3: Sensitivity 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 LMS-320, 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 LMS-320, 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 decrease sensitivity;
press ↑ to increase sensitivity. When it's set at the desired level, press

. (When you reach the maximum or minimum limit, a tone sounds.)

EXIT

At left, Sonar Menu with Sensitivity command selected. At right, the

Sensitivity Control Bar.

51

NOTE:

If you want to change the sensitivity in Manual Mode, first turn off

|↓ to

Auto Sensitivity: from the Sonar Page, press

|

S

ENSITIVITY

ENT

|↑ to

S

ENSITIVITY

|

. Press ↓ or ↑ to pick a different

ENT

MENU

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

EXIT

A

UTO

.

Important Tip:

While you are experimenting and learning, it's possible to scramble
the settings so that the sonar picture disappears from your screen.
If that happens, remember that it's easy to switch back to full
automatic operation by simply restoring the factory auto settings.
Here's how:

To Restore Factory Settings

1. Press

TIONS

MENU|MENU

|

.

ENT

2. The unit asks if you want to reset all the options. Press ← to

|

Y

ES

. All options are reset, and the unit reverts back to the Map

ENT

Page at the 4000 mile zoom range. (Any recorded sonar logs or 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. Here's why.

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 recom-

mend 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 Lowrance sonar to Fish I.D.,
which screened out the schools of jellyfish and clearly showed the game
fish there as fish symbols.

|↓ to

S

YSTEM SETUP

|

ENT

|↓ to

R

ESET 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 just plain fun, this program
can help you learn both basic and advanced operations without burning
boat fuel! Lowrance is the first sonar manufacturer 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.

53

Free training emulator is available for your unit 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, even 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.

54

Section 4: Sonar Options & Other Features

Material in this section is arranged in alphabetical order.

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.

At left, Sonar Menu with Sonar Features selected. In the Sonar

Features menu, Noise Rejection is selected with ASP in the default low

setting (center, dual-frequency menu; at right, single-frequency menu).

To change the ASP level:

1. From the Sonar Page, press

2. Press → ↓

or ↓ to

N

OISE REJECTION

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

4. To return to the previous page, press

MENU

|

|↓ to

ENT

S

ONAR FEATURES

.

ENT

EXIT|EXIT

|

.

ENT

.

.

55

Alarms

This unit has three different types of sonar alarms. The first is the Fish
Alarm. It sounds when the Fish I.D. feature determines that an echo
is a fish.

Another alarm is the Zone Alarm, which consists of a bar on the side of
the screen. Any echo on the chart that appears inside this bar triggers
this alarm.

The last alarm is the Depth Alarm, which has both a Shallow and a
Deep setting. Only the bottom signal will trigger this alarm. This is
useful as an anchor watch, a shallow water alert or for navigation.

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.

At left, Main Menu and Sonar Alarms command.

At right, the Sonar Alarms menu.

To adjust and turn on the shallow alarm:

1. Press

MENU|MENU

2. Press → to

S

|↓ to

A

LARMS

HALLOW ALARM DEPTH

|

|

ENT

ENT

|↓ to

.

S

ONAR ALARMS

|

ENT

.

3. Press ↑ or ↓ to change the first number, then press → to move the
cursor to the next number and repeat until the depth is correct, then
press

ENT

.

56

4. Press ← to

S

HALLOW ALARM ENABLED

|

ENT|EXIT|EXIT|EXIT

.

5. To turn off the alarm, press

S

ONAR ALARMS

|

ENT|ENT|EXIT|EXIT|EXIT

MENU|MENU

.

|↓ to

A

LARMS

|

ENT

|↓ to

To switch to a different depth setting, open the Sonar Alarms menu and
repeat the instructions in step 3 above.

To adjust and turn on the deep alarm:

1. Press

MENU|MENU

2. Press ↓ to

D

EEP ALARM ENABLED

|↓ to

A

LARMS

|

ENT

|→ to

|↓ to

S

ONAR ALARMS

D

EEP ALARM DEPTH

|

|

ENT

ENT

.

.

3. Press ↑ or ↓ to change the first number, then press → to move the
cursor to the next number and repeat until the depth is correct, then
press

4. Press ← to

5. To turn off the alarm, press

S

ONAR ALARMS

ENT

.

D

EEP ALARM ENABLED

|

|↓ to

ENT

|

ENT|EXIT|EXIT|EXIT

MENU|MENU

D

EEP ALARM ENABLED

.

|↓ to

|

ENT|EXIT|EXIT|EXIT

A

LARMS

|

ENT

|↓ to

.

To switch to a different depth setting, open the Sonar Alarms menu and
repeat the instructions in step 3 above.

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

A

LARMS

|

ENT

|↓ to

S

ONAR ALARMS

|

ENT

.

2. Press ↓ to

Z

ONE ALARM ENABLED

|→ to

A

DJUST ZONE

|

ENT

.

At left, Sonar Alarms menu, with Adjust Zone command selected.

At right, Adjust Zone Alarm selection box, with Upper selected.

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

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

U

PPER

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

57

, then press ↑ or ↓ to move the bottom of the bar to the desired

L

OWER

depth.

5. Press

EXIT

|← to

Z

ONE ALARM ENABLED

|

ENT|EXIT|EXIT|EXIT

. Now, any
echo — fish, bottom, structure — within the zone alarm's depth range
will trigger the zone alarm.

6. To turn off the alarm, press

|

S

ONAR ALARMS

ENT

|↓ to

Z

ONE ALARM ENABLED

MENU|MENU

|↓ to

|

ENT|EXIT|EXIT|EXIT

A

LARMS

|

ENT

|↓ to

.

To switch to a different depth setting, open the Sonar Alarms menu and
repeat the instructions in steps 3 and 4 above.

Fish Alarm

Use the fish alarm for a distinctive audible alarm when fish or other
suspended 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.

Sonar Alarms menu with Fish Alarm selected. The check box to the left

is blank, indicating the alarm is turned off.

To turn the fish alarm on:

1. Press

2. Press ↓ to

MENU|MENU

F

ISH ALARM

3. To turn off the alarm, press

S

ONAR ALARMS

|

ENT

|↓ to

A

LARMS

|

ENT|EXIT|EXIT|EXIT

|↓ to

F

ISH ALARM

|

|↓ to

ENT

S

ONAR ALARMS

.

MENU|MENU

|

ENT|EXIT|EXIT|EXIT

|↓ to

A

LARMS

.

|

ENT

|

.

ENT

|↓ to

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.

58

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 current speed into consid­eration when making your calculation.) After you have a correction fig­ure, here's how to enter it:

1. Press

|

S

PEED

ENT

MENU|MENU

.

|↓ to

S

ONAR SETUP

|

ENT

|↓ to

C

ALIBRATE WATER

2. Enter the number you calculated earlier: press ↑ or ↓ 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

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
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.

At left, Sonar Page menu with Chart Speed command selected.

At right, Chart Speed Control Bar.

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. To change chart speed:

59

1. From the Sonar Page, press

MENU

|↓ to

C

HART SPEED

|

ENT

.

2. The Chart Speed Control Bar appears. Press ↓ to decrease chart
speed; press ↑ to increase chart speed.

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

EXIT

.

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.

At left, Sonar Page menu with Depth Cursor command selected. At

right, sonar chart with the depth cursor active. The line indicates the

large fish is 34.64 feet deep.

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

Cursor line

Depth box

1. From the Sonar Page, press

MENU

|↓ to

D

EPTH CURSOR

|

ENT

.

2. The depth cursor appears. Press ↓ to lower the cursor line; press ↑ to
raise the cursor line.

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. However, depending upon the bottom
depth and the current range, you can change the range to a different
depth. To do this:

1. From the Sonar Page, press

MENU

|↓ to

60

D

EPTH RANGE

|

ENT

.

At left, Sonar Page menu with Depth Range command selected. At

right, the Depth Range Control Scale.

2. The Depth Range Control Scale appears. Press ↑ or ↓ to select a dif­ferent depth range. A black bar highlights the selected range. Range
numbers in gray cannot be selected.

3. When the new range is selected, press

to clear the menu.

EXIT

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 feet to 4,000 feet.

To switch to Manual Depth Range:

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

|↓ to

MENU

2. Press ↑ to

A

UTO DEPTH RANGE

D

EPTH RANGE

3. Press ↓ or ↑ to select a different depth range. A horizontal black bar
highlights the selected range.

4. When the new range is selected, press

To turn Auto Depth Range on again:

1. From the Sonar Page, press

NOTE:

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

|

.

ENT

|

and the Depth Range Control Scale appears.

ENT

to clear the menu.

EXIT

MENU

|↓ to

A

UTO DEPTH RANGE

|

ENT|EXIT

.

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

61

the surface to the bottom can be shown. This enlarges the sonar targets
to best suit your fishing needs and water conditions.

At left, Sonar Page Menu with Upper and Lower Limits command se-

lected. At right, Sonar Chart Limits menu, with Upper Limit selected.

To change the upper and lower limits:

1. From the Sonar Page, press

MENU

|↓ to

U

PPER AND LOWER LIMITS

|

ENT

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

.

2. To set the upper limit, press

. Press ↑ or ↓ to change the first

ENT

number, 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

L

OWER LIMIT

EXIT

.

|

. Press ↑ or ↓ to

ENT

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

EXIT|EXIT|EXIT

Area "zoomed"

.

Fish arches

Normal display, in auto depth range mode, left. At right, display

"zoomed" with Upper and Lower Limits focusing on the portion of the

water column from 20 feet to 40 feet deep. In the "zoomed" image, note
the target definition at lower left, showing a fish holding just above the
structure. At top right, two game fish are attacking a school of bait fish.

62

To turn off upper and lower limits:

From the Sonar Page, press

MENU

|↓ to

A

UTO DEPTH RANGE

|

ENT|EXIT

.

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're 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

Grayline



horizontal bars.

Bottom signal

Sonar Page showing FasTrack.

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.

63

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.

Does that mean Fish I.D. is broken? No — the feature is simply 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. The default for Fish I.D. is off.

Sonar Features menu with Fish I.D. Symbols selected (at left, dual-

frequency menu; at right, single-frequency menu). When the check box

to the left is checked, the feature is on.

64

Fig. 1 A

Fig. 1 B

Many fish

arches visible

Fig. 2 A

Fish arches

above structure

Fewer fish

symbols visible

Fig. 2 B

No fish shown

FasTrack graph

confirms fish

At left, figures 1A and 2A show Sonar Page in normal chart mode. At

right, figures 1B and 2B show the same underwater scene with Fish I.D.

turned on. Note how arches are replaced with symbols.

To turn the Fish I.D. feature on:

1. From the Sonar Page, press

2. Press → ↓ or

→ to

F

ID S

ISH

YMBOLS

|↓ to

MENU

|

ENT|EXIT|EXIT

S

ONAR FEATURES

.

|

ENT

.

To turn off Fish I.D., repeat the instructions in step 1.

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:

(Note: These instructions will turn on FishTrack and Fish I.D. at the
same time.)

1. From the Sonar Page, press

MENU

|↓ to

S

ONAR FEATURES

|

ENT.

65

2. Press → ↓ to

p

F

ISH

ID D

|

ENT|EXIT|EXIT

EPTHS

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

Symbols with

FishTrack de

ths

Sonar Features menu with Fish I.D. Depths selected (at left, dual-

frequency menu; center, single-frequency menu). When the check box to

the left is checked, the feature is on. At right, Sonar Page showing Fish

I.D. symbols and FishTrack depths turned on.

FishReveal

When displaying actual sonar returns, the FishReveal feature uses 10
levels of gray tones to show fish targets hidden by surface clutter,
thermoclines, weed beds and other cover.

The normal mode of operation (with FishReveal turned off) shows the
weakest echoes as black and the strongest echoes in light gray. Since
all weak echoes are black, fish arches show boldly against the white
background. The drawback is that all weak echoes – such as thermo­clines – are also emphasized. This can make it hard to distinguish fish
signals inside thermoclines or other cover.

In FishReveal mode, the weakest echoes are white and the strongest
echoes are black. Echoes in between vary in gray in proportion to their
signal strength. The Grayline control determines the range for black to
white. Also note that when using FishReveal, we recommend that you
turn off Auto Sensitivity and turn up Sensitivity to near maximum.

66

Sonar Color Mode command with FishReveal selected

(at left, dual-frequency menu; at right, single-frequency menu).

To turn FishReveal on:

1. From the Sonar Page, press

MENU

|↓ to

S

ONAR FEATURES

|

ENT

.

2. Press ↓ to

3. Press

EXIT

S

ONAR COLOR MODE

|↑ to

A

UTO SENSITIVITY

|

ENT

|

|↓ to

ENT

F

|↑ to

ISHREVEAL

S

ENSITIVITY

|

ENT

|

.

ENT

.

4. Press ↑ until the Sensitivity Control Bar reads 100% (or close to it),
then press

Fish

not

visible

Fish
arch

. (If you reach the maximum limit, a tone sounds.)

EXIT

Visible

fish

Fish

arches

Sonar chart in regular grayscale mode, left, and in FishReveal mode,
right. Notice how shallow fish formerly hidden in the surface clutter

become visible in FishReveal mode.

NOTE:

Water conditions vary greatly, and that affects sonar performance.
Under certain conditions, FishReveal will show you more fish than
normal grayscale mode, but the reverse will be true in other circum­stances. We suggest you become familiar with both modes so you can
best match your sonar's performance to the current water conditions.

67

Frequency (Change Transducer Frequency)
(LMS-320DF only)

The LMS-320DF transducer operates with 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.

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

|

50 KH

.

ENT

Z

to clear the menu.

MENU

|↓ to

S

ONAR FEATURES

68

|

ENT

.

To change the frequency setting to 200 kHz:

|↓ to

1. From the Sonar Page, press

MENU

S

ONAR FEATURES

|

ENT|ENT

.

2. Press

EXIT|EXIT

Grayline



to clear the menu.

Grayline lets you distinguish between strong and weak echoes. It
"paints" gray 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 or no gray line. A hard bottom returns a strong
signal which causes a wide gray line.

If you have two signals of equal size, one with gray and the other with­out, then the target with gray is the stronger signal. This helps distin­guish weeds from trees on the bottom, or fish from structure.

Grayline is adjustable. Experiment with your unit to find the Grayline
setting that's best for you.

At left, Sonar Page menu with Grayline command selected.

At right, the Grayline control bar.

To adjust the Grayline level:

1. From the Sonar Page, press

MENU

|↓ to

G

RAYLINE

|

ENT

.

2. The Grayline Control Bar appears. Press ↓ to decrease Grayline;
press ↑ to increase Grayline.

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

EXIT

.

69

Fig. 1A

Fig. 1B

Fig. 2A

Fig. 3A

Hard

structure

Hard

bottom

Fish near

structure

Grayline

Fig. 2B

Muddy

bottom

Grayline

Fig. 3B

Muddy

bottom

Hard

bottom

Grayline

This series of figures shows how different Grayline settings can reveal
more information. The "A" figures to the left show locations with Gray­line set at the factory level of 64 percent. At right, the "B" figures show
the same locations with Grayline increased to 84 percent. In Figure 1B,
no fish are near the left structure, but the right structure shows fish
holding next to the structure. Notice in figures 2B and 3B how Gray­line displays a hard, rocky bottom (the drop-offs) with a wider gray
line. The muddier bottom below those drop-offs appears as a narrower
gray line.

70

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
(to play a recorded sonar chart log, see the entry in this section for So­nar Simulator). If you have a personal computer and Internet access,
visit our web site, www.lowrance.com, and download the free Sonar
Viewer and the emulator for your unit. These programs will allow you
to replay sonar logs on your personal computer.

At left, the Sonar Page menu with the Log Sonar Chart Data command

selected. At right, Sonar Chart Logging menu, with the Start Logging

command selected. 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
and the Sonar Page title bar shows the name of the file you are record­ing. Warning messages will appear as recording time begins 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
quality and record for a longer period of time. After you've changed
the settings, select

MENU

|↓ to

L

OG SONAR CHART DATA

C

HART QUALITY

S

TART LOGGING

.

|

.

ENT

. The menu clears

ENT

F

ILE NAME

if you want to

if you want to lower the file

Noise Rejection

See the entry on Advanced Signal Processing in this section.

Overlay Data

To change the digital data shown on top of the Sonar Page or the Map
Page:

71

First, press

To select data for display:

PAGES

1. From the Map or Sonar page, press

2. Press ↓ or ↑ to select Data Type|

, use → or ← to select a Page Name, then press

ENT

MENU

.

|↓ to

O

VERLAY DATA

|

ENT

EXIT

.

Overlay Data command on the Sonar Menu, at left. Overlay Data

Shown selection menu, right. In this example, we scrolled down the

data list to highlight "Ground Speed."

When selected, the data type shifts to the top of the data list and a
check mark appears beside the data type. (If you wish, you may now
use ↓ or ↑ to select other Data Types for display.)

.

Data list showing "Ground Speed" selected to display on Sonar Page.

3. To return to the previous page, press

To turn off displayed data:

1. From the Map or Sonar page, press

2. Press ↓ or ↑ to select Data Type|

MENU

ENT

EXIT|EXIT

. The selected data type disap-

|↓ to

.

O

VERLAY DATA

|

ENT

.

pears from the top of the list and reverts to its previous, unchecked po­sition. (If you wish, you may now use ↓ or ↑ to select other Data Types
to turn off.)

72

3. To return to the previous page, press

To change displayed data font size:

1. From the Map or Sonar page, press

MENU

EXIT|EXIT

|↓ to

.

O

VERLAY DATA

|

ENT

.

2. Press ↓ or ↑ to select Data Type|press → or ← to Data Size|

EXIT

.

The selected data type will be displayed in the new size. (To change the
font size for another Data Type, press

and repeat these steps, be-

ENT

ginning with step two above.)

3. To return to the previous page, press

EXIT

.

Tip:

If you wish, you can change the displayed data font size when you
select a data type:

1. From the Map or Sonar page, press
|

ENT

.

D

ATA

2. Press ↓ or ↑ to select Data Type|press → or ← to select Data

Size|

ENT

.

The data will be shown in the new font size. To return to the previ­ous page, press

Steering
arrow

EXIT|EXIT

.

MENU

|↓ to

O

VERLAY

At left, Map Page showing boat cruising Puget Sound, Washington,

with Overlay Data turned on. This example shows Depth, Ground

Speed and the Steering Arrow. Note that the Steering Arrow always

points directly to the destination you are navigating toward. In this
case, the boater is headed on a northwesterly course of 275º. Since the
helmsman is on course, the Steering Arrow is pointing straight ahead.

If the helmsman veered off course, the arrow would show which direc-

tion to steer to get back on course toward the destination. At right,

Sonar Page with Overlay Data turned on. This example shows Depth,

Ground Speed and the Track the boat is following.

73

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.

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.

At left, Sonar Menu with Ping Speed command selected.

Ping Speed Control Bar, right, at default setting.

To change Ping Speed:

1. From the Sonar Page, press

MENU

|↓ to

P

ING SPEED

|

ENT

.

2. The Ping Speed Control Bar appears. Press ↑ to increase ping speed;
press ↓ to decrease ping speed. When it's set at the desired level, press

EXIT

74

.

To adjust Sensitivity:

1. From the Sonar Page, press

MENU|ENT

.

2. The Sensitivity Control Bar appears. Press ↓ to decrease sensitivity;
press ↑ to increase sensitivity. When it's set at the desired level, press

. (When you reach the maximum or minimum limit, a tone sounds.)

EXIT

To turn off HyperScroll:

1. From the Sonar Page, press

MENU

|↓ to

P

ING SPEED

|

ENT

.

2. The Ping Speed Control Bar appears. Press↓ to decrease ping speed
to 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. The 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 it's entry in this section.

Reset Options

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

1. Press

MENU|MENU

2. Press ← to

Y

ES

|

ENT

|↓ to

.

S

YSTEM SETUP

|

ENT

|↓ to

R

ESET OPTIONS

|

ENT

.

3. All the menus are cleared and the unit reverts to the Map Page at
the 4000 mile zoom range, just as if you had turned it on for the first
time. All options have been returned to the factory settings.

At left, System Setup menu with Reset Options command selected. At

right, the Reset Options dialog box, with "Yes" selected.

75

NOTE:

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 window that
shows distance traveled, called Water Distance ("W 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

|

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

ENT

|↓ to

S

ONAR SETUP

|

ENT

|↓ to

R

ESET WATER DIS-

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. 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 indi-
cators perform as if the transducer's lower in the water than it really is.

1. Press

MENU|MENU

|↓ to

S

ET KEEL OFFSET

|

ENT

.

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

. The depth indicators now accurately show the depth

EXIT

of water beneath the keel.

76

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

MENU|MENU

|↓ to

S

ET KEEL OFFSET

|

ENT

.

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

. The depth indicators now accurately show

EXIT

the water depth from surface to bottom.

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 Grayline 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 wish 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

77

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

MENU|ENT

.

2. The Sensitivity Control Bar appears. Press ↓ to decrease sensitivity;
press ↑ to increase sensitivity. When it's set at the desired level, press

. (When you reach the maximum or minimum limit, a tone sounds.)

EXIT

At left, Sonar Menu with Sensitivity command selected. At right, the

Sensitivity Control Bar.

To adjust sensitivity in manual mode:

1. First, turn off Auto Sensitivity: from the Sonar Page, press
to

A

UTO SENSITIVITY

2. Press ↑ to

|

ENT

S

ENSITIVITY

.

|

and the Sensitivity Control Bar appears.

ENT

MENU

|↓

Press ↓ or ↑ to pick a different sensitivity setting. When it's set at the
desired level, press

EXIT

.

To turn Auto Sensitivity back on:

From the Sonar Page, press

MENU

|↓ to

A

UTO SENSITIVITY

|

ENT|EXIT

NOTE:

To return to the original factory setting for Auto Sensitivity, see the
entry in this section on Reset Options. If sensitivity is in manual
mode, the Reset Options command will switch back to Auto and re­set the factory setting at the same time.

78

.

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.

Sonar Color Mode

The default color scheme for the sonar chart is grayscale, but we offer
other variations to suit your viewing preferences. You can select the
chart to be displayed in reverse grayscale, bottom black or FishReveal
mode. (For more information on FishReveal, see the entry on that topic
elsewhere in this section.)

To change the chart mode color scheme:

1. From the Sonar Page, press

2. Press ↓ to

S

ONAR COLOR MODE

3. Press ↓ or ↑ to Mode Name|

4. Press

EXIT|EXIT

to return to the Sonar Page.

MENU

|

ENT

ENT

|↓ to

.

.

S

ONAR FEATURES

|

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

|← or→ to

|↓ to Option Name|

S

ONAR

EXIT

.

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

79

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. (See the Zoom section for more information.)

Full Sonar Chart. The Overlay Data (depth and water temperature)

are both set to the small text size.

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 at the bottom left corner of
the screen.

Split Zoom Sonar Chart. Image at left shows the left window zoomed to

2X. The right image shows the left window zoomed to 4X. The depth

overlay data is set to the default large text size; the water temperature

is set to the small text size.

80

Split Frequency Sonar Chart
(LMS-320DF only)

This page shows sonar data from the 50 kHz transducer element 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 Sonar Chart page, with

50 kHz view at left and 200 kHz view at right.

You can adjust the sensitivity in each window.

To adjust sensitivity in auto mode:

1. Press

MENU|ENT

.

2. The unit asks which you wish to adjust. Press ← or→ to select the
one you want |

ENT

.

3. The Sensitivity Control Bar appears. Press ↓ to decrease sensitivity;
press ↑ to increase sensitivity. When it's set at the desired level, press

. (When you reach the maximum or minimum limit, a tone sounds.)

EXIT

The Split Frequency Sonar Chart page allows you to adjust

sensitivity separately for each window.

81

Digital Data/Chart

This mode shows the chart on the right side of the screen. The left side has
six large digital boxes or windows 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; Temperature #2
and Temperature #3. (Note: Temperature #2 and #3 require additional
optional temperature sensors.)

Digital Data/Chart

Customizing the Digital Data/Chart Screen

The Digital Data/Chart screen can be customized to show digital data
different from the defaults first shown. To customize this screen:

1. From the Sonar Page (in Digital Data mode), press
|

C

USTOMIZE

. (Keep scrolling down and Customize will appear.)

ENT

MENU

|↓ to

The Customize command will not appear until you begin

scrolling down the Sonar Page menu. At far left, the

pop-up help box conceals part of the menu.

2. The W Speed window title bar flashes, indicating the window con-

tents can be changed. Press

|↑ or ↓ to select data type|

ENT

ENT|EXIT

.

82

Options List for customizing Digital Data windows. At left, the list first

appears with Water Speed selected. At right, Maximum Speed has been

picked to replace Water Speed in the top digital data window.

Tip:

You can customize other digital data windows before returning to
the Sonar Page. After changing the first window by selecting the
Data Type and pressing Enter, use the ↓ key to select another win­dow to change. When the selected window title bar flashes, press

|↑ or ↓ to select data type|

ENT

finished customizing, then press

Flasher

The Flasher page represents a flasher style sonar. A circular dial shows
all returning echoes at a high screen refresh rate. It uses the Grayline
feature to show weaker targets as shades of gray. The bottom depth is
also shown as a black bar across the outer circle. There is also a narrow
chart display on the left of the screen.

. Repeat these steps until you're

ENT

to return to the Sonar Page.

EXIT

Surface clutter

Fish signal,

approximately

16 feet

Flasher page.

83

Bottom signal

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.

Map With Sonar split screen option. At far right, the full Map Page is

shown. The Pages Menu with the Map option list is shown in the

center. At right, the Map With Sonar split screen is shown.

When this screen is activated, you need to specify which side the Menu,
Zoom In and Zoom Out keys correspond to. To do this, press

PAGES|PAGES

is the active window. To switch back, just press

. The window with the black title bar at the top of the screen

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

|

S

ONAR SIMULATOR

ENT

.

MENU|MENU

|↓ to

S

ONAR SETUP

|

ENT

|↓ to

At left, Main Menu with Sonar Setup command selected. Center, sub-

menu with Sonar Simulator command selected. At right, Sonar Simu-

lator menu, with simulator turned off (check box is unchecked).

84

NOTE:

With Simulate Position checked, the simulator will also automati­cally run the GPS simulator (if GPS data was recorded with the so­nar log).

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 pressing

|

S

ETUP

Title bar with chart file name

Sonar Page, playing a recorded sonar chart in Sonar Simulator mode.

ENT

|↓ to

S

ONAR SIMULATOR

|

ENT|ENT|EXIT

MENU|MENU

.

|↓ to

"Play"
symbol
flashing

S

ONAR

Tip:

The Sonar Simulator can use sonar charts that you or a friend have
recorded (logged) on an 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

MENU|MENU

C

3. Press ↓ or ↑ to select chart name|

|

O

N

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 sites you want to return to.

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.

|↓ to

HART USED

S

ONAR SETUP

|

ENT

|

ENT

|↓ to

S

ONAR SIMULATOR

|

ENT

.

|↑ to

ENT

S

ONAR SIMULATOR

85

.

.

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. Here's how:

1. Press

MENU|MENU

2. Press ↓ or ↑ to chart name|

|↓ to

B

ROWSE

ENT

MMC F

|↓ to

P

ILES

LAY

|

ENT|ENT

|

ENT|EXIT

.

.

Menu sequence for playing a sonar chart log from the MMC File List.

NOTE:

For some great practice, try running the Sonar Simulator and the
GPS Simulator at the same time. This will really give you a feel for
how the unit will work in the field.

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

To turn on sonar and start the chart scrolling again, repeat the above step.

MENU

|↓ to

S

TOP CHART

|

ENT|EXIT

.

86

Sonar Menu with Stop Chart command selected. The box is unchecked,

indicating that 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, or high.
It can also be turned off. The default level is off.

To adjust the Surface Clarity level:

1. From the Sonar Page, press

MENU

|↓ to

S

ONAR FEATURES

|

ENT

.

Sonar Features menu with Surface Clarity selected (at left, dual-

frequency menu; at right, single-frequency menu).

2. Press → to

press

ENT

S

URFACE CLARITY

).

3. Press ↓ or ↑ to select clarity level|

|

(For single-frequency units, just

ENT.

EXIT|EXIT|EXIT

.

87

Surface clutter

In the illustration at left, Surface Clarity is turned off.

The right view shows Surface Clarity set at High.

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

once doubles the size (2X) of all echoes on the screen.

ZIN

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
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

.

key is pressed.

ZIN

ZOUT

key once will enable a 2X zoom which

ZIN

, to return the display to the normal mode.

At left, Sonar Page, normal view. Center, same view zoomed to 2X.

Right, same view zoomed to 4X

88

Zoom & 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 (see page 61)
and turn on 2X or 4X Zoom. Then, simply press ↑ or ↓
down the water column.

to pan up and

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 factory 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 certain 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 11 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 operates only in demo mode:

The transducer has not yet been connected or has been disconnected.
To leave demo mode, make sure the transducer is securely connected
before turning the unit on.

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 both the transducer and power connectors. Make certain both

are securely plugged in to the unit.

Weak bottom echo, digital readings erratic, or no fish signals:

1. Make certain 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. Do NOT use RTV
silicone rubber adhesive or Marine-Tex epoxy.

2. Electrical noise from the boat's motor can interfere with the sonar.

91

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.

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 certain 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

display 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.

92