Humminbird Single Beam 105SX User manual

®
Operations Manual

THANK YOU
Thank you for choosing Humminbird, America’s #1 name
in fishfinders. Humminbird has built its reputation by
designing and manufacturing top-quality, thoroughly
reliable marine equipment. Your Humminbird is designed
for trouble-free use in even the harshest marine
environment.
In the unlikely event that your Humminbird does require
repairs, we offer an exclusive Service Guarantee - free of
charge during the first year after purchase, and available at
a reasonable rate after the one-year period. Complete
details are included at the end of this manual.
We encourage you to read this operations manual carefully
in order to get full benefit from all the features and uses of
your Humminbird product. Also, to register your purchase
and help us learn more about you, please fill out the
warranty registration card at the back of this manual.
WARNING! This device should not be used as a
navigational aid to prevent collision, grounding,
boat damage, or personal injury. When the boat is
moving, water depth may change too quickly to
allow time for you to react. Always operate the boat
at very slow speeds if you suspect shallow water or
submerged objects.
WARNING: Dis-assembly and repair of this electronic unit should only be performed
by authorized service personal. Any modification of the serial number or attempt to
repair the original equipment or accessories by unauthorized individuals will void the
warranty. handling and/or opening this unit may result in exposure to lead, in the form
of solder.
Warning: This product contains lead, a chemical known to the State of
California to cause cancer and birth defects and other reproductive harm.

Section 1: INSTALLATION PREPARATION . . . . . . . . . . . . . . . 2
Parts Supplied . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2
Accessories . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2
Installation Overview . . . . . . . . . . . . . . . . . . . . . . . . . 2
Alternative Transducers and Mounting Methods. . . . . . 4
Transducer Exchange . . . . . . . . . . . . . . . . . . . . . . . . . 5
Beginning Installation . . . . . . . . . . . . . . . . . . . . . . . . . 5
Section 2: USING THE 105SX. . . . . . . . . . . . . . . . . . . . . . . 6
How Sonar Works . . . . . . . . . . . . . . . . . . . . . . . . . . . 6
Simulator Operation . . . . . . . . . . . . . . . . . . . . . . . . . . 7
What You See On Screen . . . . . . . . . . . . . . . . . . . . . . 8
Control Functions. . . . . . . . . . . . . . . . . . . . . . . . . . . 11
Menu Functions . . . . . . . . . . . . . . . . . . . . . . . . . . . . 14
Section 3: ADVANCED FEATURES. . . . . . . . . . . . . . . . . . . 21
Using the Diagnostic Feature. . . . . . . . . . . . . . . . . . . 21
Section 5: MAINTENANCE AND WARRANTY. . . . . . . . . . . 22
Maintenance . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 22
Troubleshooting . . . . . . . . . . . . . . . . . . . . . . . . . . . . 23
Warranty . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 26
Service Policy . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 27
Customer Resource Center . . . . . . . . . . . . . . . . . . . . 28
Specifications . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 29
TABLE OF CONTENTS
P/N 531082-1 R11012E

2
INSTALLATION PREPARATION
PARTS SUPPLIED
PARTS SUPPLIED
Before installing your 105SX, please ensure the following parts are
included in the box:
• 105SX fishfinder
• Transducer with 20' (6m) of cable and mounting hardware kit
• Mounting system and mounting hardware kit
• 6' (2m) power cable
• Publications kit
• Temperature Probe
If any of these items is missing, call our Customer Support Hotline.
ACCESSORIES
Humminbird offers a wide assortment of accessories that complement
and expand the capability of your new 105SX. These accessories are
designed with the same high standards and are backed by the same one-
year warranty. The Humminbird Accessory catalog included with your unit
contains descriptions of the many accessories available and ordering
information. All Humminbird accessories are available through your full-
service Humminbird dealer or factory direct through our number listed in
the Customer Support section.
INSTALLATION OVERVIEW
The 105SX consists of two primary components to install: the control
head and the transducer.
The control head contains the sonar transmit and receive circuitry, as well
as the user controls and display. It should be installed in a location that
provides access to the controls and visibility while in use. The control
head mounts on a quick disconnect mounting system that swivels and
tilts providing flexibility for viewing from almost anywhere on the boat.
The transducer converts electrical energy from the transmitter into
mechanical pulses or sound waves. The transducer also receives the
reflected sound waves and converts them back into electrical signals for
display on the control head. It should be installed in contact with the

3
INSTALLATION PREPARATION
INSTALLATION OVERVIEW
surface of the water in an area that has smooth water flow - usually on
the transom of the boat. There are several mounting options for the
transducer. Review the following section to determine the method that
works for you and your boat.
Determining How to Mount the Transducer
The 105SX includes a model XHS- 6-24 transducer. This transducer can be
mounted on the transom of the boat, or bonded to the inside of a
fiberglass hull boat.
The transom installation, which is the
most widely used, places the
transducer on the outside of the boat
hull. This technique produces the least
signal loss, and provides a way to
adjust the transducer after installation.
As an alternative to transom mounting,
it is possible on many fiberglass-hulled
boats to glue the transducer on the
inside of the boat hull. Since fiberglass
has similar sonar characteristics as
water, the sonar signal can pass through the boat hull with minimal loss.
The hull of the boat must be single layer construction (not double-hulled).
Also, any air trapped in the lamination of the fiberglass would prevent the
sonar signal from passing through.
Inside the hull installations require
no holes be drilled into the boat and
through experimentation, high-
speed operation comparable to
transom mounting can be achieved.
Two part, slow cure epoxy (not
included) is required to glue the
transducer in place.
Transom Mounted Transducer
Inside the Hull Mounted Transducer

4
ALTERNATE TRANSDUCERS AND MOUNTING METHODS
The 105SX comes with everything necessary for installation and operation
on most boats. However, there are several situations which may require a
different type of transducer. Inboard boats, wood or metal hulls, and sail
boats create unique transducer mounting needs. Alternate transducers
and mounting methods are detailed below.
Portable Mounting
The standard transducer can be adapted for portable installations using
part number
MHX-SPT. This accessory adapts your transducer to a suction cup mount
for temporary installation on the boat hull or other surface.
Trolling Motor Mounting
The standard transducer can also be adapted
to mount on most trolling motors using part
number AD-STM. This accessory includes a
bracket and hose clamp that allows
mounting the transducer to the body of
most trolling motors.
Thru-Hull Mounting
Thru-hull transducers install through a hole
drilled in the hull of the boat. Larger boats or
boats with inboard motors create turbulence
that make transom mounting ineffective. Also,
hulls that are very thick or are double layered,
or made from materials such as wood or
metal, (which do not conduct sonar signals)
make inside the hull mounting inadvisable.
Thru-hull mounting may require the use of a
fairing block to level the transducer with the
waterline. Also, since special tools and
knowledge may be required to perform this
type of installation it is best to refer to a
qualified marine technician.
INSTALLATION PREPARATION
ALTERNATE TRANSDUCERS AND MOUNTING METHODS

TRANSDUCER EXCHANGE
Other transducers are available as replacements for the standard
transducer. You may exchange your new and unassembled transducer for
another type by returning it to the address listed in Customer Support.
Some transducers may have additional costs. Refer to the Accessory cata-
log or call Customer Support for information.
BEGINNING INSTALLATION
Now that you have determined the transducer mounting method, you
can begin installation of the 105SX. The fold out installation guide
included provides detailed step by step instructions for installation of the
control head and transducer. For transom mount transducer installations,
you will need the mounting template in the center of this manual.
In addition to the parts included you need the following for installation
and operation:
•Apowered hand drill and various drill bits
• Phillips and flat-head screw drivers
• A ruler or measuring tape
• Pen or pencil
•12 volt power source (your boat’s battery)
• A 1-amp fuse
•Afuse holder (if you are wiring directly to the boat’s battery)
•Silicone sealant (for sealing drilled holes)
•2-part, slow-cure epoxy (for inside the hull transducer installations)
INSTALLATION PREPARATION
TRANSDUCER EXCHANGE
5

USING THE 105SX
HOW SONAR WORKS
6
HOW SONAR WORKS
Your Humminbird unit uses sonar to
locate and define underwater
objects, define the bottom terrain, as
well as determine distance.
Sonar technology is based on sound
waves. Your Humminbird unit sends
out a sound wave signal. With this
signal it determines distance by
measuring the time between the
transmission of the sound wave and
when the sound wave is reflected off
an object. Your Humminbird uses the
reflected signal to interpret location,
size and composition of an object.
Sonar is very fast. A sound wave can travel from the surface to a depth
of 600' (185m) and back again in less than 1/4of a second. It is unlikely
that your boat can "outrun" this sonar signal.
The 105SX is a 200kHz, single-beam fishfinder. The 200 kHz frequency
provides excellent sonar resolution (the ability to distinguish small
returns or returns which are close to the bottom), while providing depth
capabilities to 600’ (185m). The shape of the sonar beam is symmetrical
and covers an area of approximately 24 degrees side to side and front to rear.
Actual depth capability depends on factors such as bottom hardness,
water conditions, and transducer installation. Units will typically read to
deeper depths in fresh water than in salt water

7
USING THE 105SX
SIMULATOR OPERATION
SIMULATOR OPERATION
The 105SX contains a simulator that allows you to use the unit as if you
are on the water. The simulator is invaluable for learning how to operate
the 105SX.
There are two ways to start the simulator. If
the unit is powered off, press and hold the
POWER button for approximately three
seconds until you hear a continuous chirp.
The simulator can also be started by
selecting the Simulator option on the start-
up screen after you power-up the unit.
When this screen is shown, simply press the
DOWN ARROW until “Simulator” is highlighted. When the screen times
out, the unit will be in simulator mode.
When in simulator operation, the 105SX responds to control inputs as if
it is in actual operation, so feel free to experiment, or to customize the
unit for your particular operation.
To exit Simulator mode, power the unit off.
When in simulator mode, the word “simulator” will flash on and
off in the top center part of the display.
FEATURE MEMORY
If your 105SX is installed with a transducer connected, any changes you
make to the set-up while in Simulator are retained in the unit’s memory.
This allows you to use simulator to experiment with the various set-up
options, and retain your selected settings for normal operation.

If you are using the 105SX in Simulator when no transducer is connected,
any selected options are lost when the unit is powered off. The 105SX
will return to Factory Settings, or options selected when last used with a
transducer, if no transducer is connected.
IMPORTANT: A transducer must be connected to the 105SX in
order to retain user settings selected when in simulator mode. If
no transducer is detected, the unit defaults to pre-selected options
when powered off.
What You See On-Screen
Your 105SX uses a 128 x 64 matrix
FSTN LCD display. This display provides
outstanding viewability in all light
conditions over a wide range of
temperatures.
At initial power-up, the 105SX uses
settings that were set at the factory.
After initial use, the 105SX will
remember the settings you enter.
There are several elements on-screen
that are common to all modes of
operation.
Speed/Temperature. The initial screen layout takes one of two basic forms
depending on presence of accessories such as Temperature or
Speed/Temperature sensors. Figure A shows the default view when the
Speed/Temp or Temperature accessory is installed. Figure B shows the default
view when no accessory is installed.
Depth. The digital depth number shows the water depth directly beneath
the transducer location.
Depth Range. The depth range is shown to the right of the screen. The
upper number is 0 indicating the surface of the water. The lower number
is one of the nine depth ranges available that best match the depth of
the water. As the depth of the water changes, the range changes as
necessary in order to retain a bottom representation on-screen.
8
USING THE 105SX
WHAT YOU SEE ON-SCREEN
Figure A

When in Auto mode, the horizontal
line at the top of the screen is the
“zero line,” representing the surface
of the water. Occasionally there is a
gap in this line. This gap indicates
the unit is updating the display even
if the bottom is not visible on-
screen, or if the bottom information
is not changing.
New sonar information appears on
the right side of the graphic area of
the display and moves to the left as
new information is displayed. The
105SX automatically selects the
appropriate depth range to show
the depth of water beneath the
transducer. This range is selected so
the bottom representation is typically shown about 2/3down the display.
Bottom. T
he graphic depiction of the bottom provides an effective tool for
understanding the composition of the
bottom. If the bottom is hard and
smooth, the bottom depiction is narrow
and dense. If the bottom is soft mud or
sand, the depiction will be thick and
less dense. This indicates much of the
signal is absorbed by the soft bottom. If
the bottom is rocky or rugged in
composition, the depiction is of varying
density and textured in appearance.
Wave action also affects the bottom
depiction. The information drawn is
a distance measurement, so if the
boat is moving up and down over
flat bottom, the bottom depiction
often appears in regular variations
that match wave timing.
9
USING THE 105SX
WHAT YOU SEE ON-SCREEN
Water Depth
Bottom Depiction
Depth Range
Figure B
Zero Line
Surface Clutter Rocky Bottom
Soft Bottom Hard Bottom

Structure. Structure is defined as any object physically attached to the
bottom. The sonar configuration of the 105SX is optimized to give the
most accurate depiction of bottom structure possible. Grass, trees,
stumps, wrecks or other debris are accurately displayed, however the
depiction of these objects varies with boat speed and direction. The best
way to learn to interpret structure is to operate the 105SX over a variety
of known conditions and experiment with user functions to best
represent those conditions on-screen.
Surface Clutter.
Surface clutter is the layer of water near the surface that
is rich in algae and other growth, and often is aerated by wind or wave
action. This area of water interferes with sonar transmission and often
appears on-screen as regular clusters of individual dots near the “0” line.
Thermoclines. Thermoclines are sharp differences in water temperature.
These are easily identified by the continuous nature of the return.
Second Returns. When a sonar signal is reflected off the bottom back to
the transducer, there is often
enough energy left in the signal to
be reflected off the surface of the
water back to the bottom a second
time. Second returns appear as a
slightly weaker bottom
representation exactly twice the
depth of the primary bottom return.
The second return is most likely to
occur in shallow water and in areas
of relatively hard bottom.
Fish ID. The 105SX uses advanced
signal processing to further evaluate
any sonar return between the
surface and the bottom. For
instance, a small school of bait fish
usually appears as a dense cluster of individual dots. If the return meets
certain additional criteria, a fish symbol is assigned. There are three
different size fish symbols used to indicate the intensity of the sonar
return. While signal intensity is a good indicator of relative fish size,
10
USING THE 105SX
WHAT YOU SEE ON SCREEN
Thermocline Second Return

different species of fish have different
sonar characteristics, so it is not always
possible to distinguish fish size
between varying species. The signal
intensity is “normalized” for depth so a
small fish close to the boat does not
appear as a large fish symbol.
ID+adds an additional piece of
information to help the user locate fish.
On selected fish symbols, the digital
depth of the designated fish is drawn
to help locate the fish vertically.
CONTROL FUNCTIONS
The 105SX uses a simple five button
keypad for all user input. Press any
button and an audible “chirp” confirms
the control input. If a button has no function or is
inappropriate for the situation, an audible “error”
is heard. The unit sounds multiple chirps.
Power. The Power button powers the 105SX up
for normal operation. When the unit is on,
POWER turns the unit off. POWER can also be
used to go directly into Simulator mode. To enter
simulator, with the unit powered off, press and
hold POWER for several seconds until a
continuous chirp is heard.
Light.
LIGHT controls the unit’s display backlight.
With the unit powered on, press LIGHT once to
turn the backlight on “high.” Press LIGHT a second time to turn the
backlight on “low,” and a third time turns the backlight off. The backlight
is very effective for low-light and nighttime operation. When the backlight
is on, the 105SX will consume more power than with the backlight off. This
is important when using the 105SX in a portable configuration powered by
a separate battery, or when powering the unit from a trolling motor battery.
11
USING THE 105SX
CONTROL FUNCTIONS
ID+Fish
Depth

12
When powering the unit from a battery such as in portable applications,
you can prolong the battery life by using the backlight at a minimum.
The three lower buttons, MENU, UP ARROW, and DOWN ARROW work
together to control the 105SX menu-controlled user functions.
Menu. MENU displays a menu on-
screen for adjustment. In normal
operation, pressing MENU repeatedly
cycles through all available menu
headings. When a menu heading
displays, the full menu appears after a short pause. A menu remains on-
screen for several seconds, and can be adjusted by using the ARROW
keys. If no adjustment is made in the allotted time, the menu disappears.
If you want the menu to remain on-screen longer press and hold
MENU—the menu will remain on-screen indefinitely. Once you release the
menu button, the screen will time out. Once a menu times out, it is still
considered the active menu. Press MENU to bring up the last menu used.
Arrow Keys. The UP ARROW and DOWN ARROW make adjustments to
menu functions. On the left side of every menu there are UP ARROW and
DOWN ARROW symbols. The symbols indicate which ARROW button has
a function in a particular situation. Either one or both ARROW buttons
can be used to adjust the menu function. A hollow ARROW symbol
means the corresponding ARROW button has no function. Pressing that
button will result in no adjustment and the “error” audible will be heard.
A solid ARROW symbol means the corresponding ARROW button can be
used to affect the menu adjustment.
The ARROW buttons often can be used when no menu is on-screen. In
these situations, pressing the ARROW button twice affects the function
of the active (last-used) menu. This is a short-cut to menu operation. The
menu appears on-screen while the adjustment is made and times out. A
frequently used menu can be adjusted very quickly using this technique.
After an adjustment is made to a menu function, the menu times out
after a few seconds and the unit returns to normal operation.
USING THE 105SX
CONTROL FUNCTIONS
Menu Heading

13
Menu Layout. All menus use the same
basic layout. The heading at the top
describes the menu function. The UP
ARROW and DOWN ARROW symbols to
the left of the menu indicate which
buttons are available for adjustment. In
menus that have several possible settings,
a range of adjustment indicator shows the total range available and the
current setting.
Within the menu are the options available. The selected option or current
setting is highlighted in the black box. If no adjustment is made, this is
the selected setting. Press an ARROW button while the menu is displayed
to select another option.
Several of the menus are multi-step. In some situations if an adjustment is
made, additional options become available for further adjustment.
Examples of these multi-step menus are Depth Range, Depth Alarm and
Zoom. See the detailed description of each function for further
explanation.
USING THE 105SX
CONTROL FUNCTIONS
Heading
Up Arrow Option
Down Arrow Option
Arrow Symbols
Selected Setting
Range of Adjustment Indicator

Menu Functions
Sensitivity. The Sensitivity function controls
the sensitivity of the sonar receiver. The
105SX automatically adjusts the level of
receiver sensitivity based on a number of
factors including the depth of the water
and the level of noise present. Noise can be
caused by other electronic devices, engines,
trolling motors, propeller cavitation and
hydrodynamic flow among others.
The user has the option of adjusting
the Sensitivity higher or lower based
on personal preference. You can select
one of 11 sensitivity settings from -5
to +5. A setting of 0 (factory setting)
has no effect on the automatic
sensitivity control. Increasing the
sensitivity (+1 through +5) enables the
unit to display the information from
progressively smaller sonar returns. By
decreasing the sensitivity bias (-1
through -5), the unit effectively filters
small sonar returns.
In murky or muddy water, it is often
helpful to reduce the sensitivity. This
prevents the display from being
cluttered with sonar returns from debris or suspended particles. In very
clear or very deep water, it may be helpful to increase the sensitivity since
even the smallest sonar return may be of interest to the user.
To adjust Sensitivity, press MENU repeatedly until the Sensitivity heading is
displayed. When the Sensitivity menu appears, use the UP ARROW to
increase the sensitivity, or the DOWN ARROW to reduce sensitivity. To
sequence through the available settings, press and hold either ARROW
button. Release the button at the setting you want to change.
14
USING THE 105SX
MENU FUNCTIONS
(+)High Sensitivity (-)Low Sensitivity
Sensitivity at “0”

15
USING THE 105SX
MENU FUNCTIONS
After an adjustment is made, the menu disappears and the new
sensitivity setting is in affect. If additional time is needed to study a
menu, press and hold the MENU button and the menu will remain on-
screen indefinitely. If you need to make an additional adjustment, press
the UP ARROW or DOWN ARROW button.
Depth Range. The Depth Range function
controls the vertical distance displayed on
the graphic area of the display. There are
nine depth ranges available. The top of
the range is always 0, or the surface of
the water. Ranges of 0–15', 0–30', 0–60',
0–120', 0–180', 0–240', 0–360', 0–480' and 0–600' are available. The
range that positions the bottom depiction closest to the bottom of the
screen, will best utilize the available display resolution.
The 105SX automatically adjusts the
depth range depending on the depth of
the water. The unit tries to maintain the
bottom depiction about 2/3down the total
range (for example, in 20' (6m) of water,
the 0-30' (0-10m) range would be
selected). This provides the best display
resolution and therefore the best target
separation possible.
The Depth Range can be adjusted manually. Press MENU repeatedly until
the Depth Range menu is visible. Two options are available:
Auto and Manual.
The manual setting enables you to adjust
the current depth range setting. The unit
no longer adjusts the Depth Range to the
most appropriate range for bottom display.
Often, the bottom may not be visible on-
screen. The digital depth readout always
determines the depth of the bottom, even
if it is not visible on-screen.

Using manual Depth Range control, you
can view sonar information from the
area near the surface in greater detail.
To return to automatic Depth Range
control, press the MENU button until
the Depth Range menu appears on-
screen and use the UP ARROW to
select AUTO.
Zoom. Zoom is similar to Depth
Range because it controls the range of
information displayed on screen.
Zoom, however, allows selection of
ranges beneath the surface so any
area of water between the surface
and the bottom can be enlarged to
provide more detailed information.
By using the full display to show a small
area of coverage, the effective display
resolution is increased, and the unit’s
ability to separate close targets is
enhanced.
There are four Zoom ranges available:
71/2', 15', 30', and 60'. These ranges
are not directly user controlled but are
instead dependent on the current
depth range. In shallow water, when
the 15' or 30' range is in use, the
Zoom range is 71/2'. If the 60' or 120'
range is in use, the Zoom range is 15',
if a 180'-480' depth range is in use,
the Zoom range is 30', and if the 600'
range is in use, the Zoom range is 60'.
16
USING THE 105SX
MENU FUNCTIONS
Depth Range
Lower Zoom Limit
Upper Zoom Limit

17
USING THE 105SX
MENU FUNCTIONS
The Zoom range is shown on the left side of
the screen and full range information is shown
on the right side of the display. Zoom can
either operate automatically, in which the
Zoom range is constantly adjusted to show the
bottom, or manually, in which the user controls
the location of the Zoom range.
Automatic Zoom is especially helpful when
looking for structure or bottom detail. The Automatic Zoom keeps the
bottom in view even in quickly changing terrain, but is most useful in
flatter areas without considerable depth variation. Manual Zoom provides
detailed information of any area from the surface to the bottom. In
manual Zoom, the Zoom range does not move as the terrain changes.
When the range is shown in the menu, the upper number represents the
top of the current Zoom range. The lower number represents the bottom
of the Zoom range. Use the UP and DOWN ARROW buttons to move this
range. The upper number can never be less than 0 (the surface of the
water), and the lower number can never be greater than the active depth
range. The difference between the two numbers (the Zoom range) is
preset and determined by the active depth range.
Once manual Zoom is selected, the display appears the same as in Auto
Zoom, but the zoom range does not change automatically.
To disable Zoom, press the MENU button until the Zoom menu is on-
screen. Use the UP ARROW to highlight Off, and let the menu time out.
When the unit is powered off, the Zoom menu returns to Zoom Off.

Depth Alarm. The 105SX contains
an audible alarm to warn you of
shallow water depths. The alarm is
adjustable to depths of 3' to 99'
(30m). When the alarm is enabled,
an audible alarm sounds if the water
beneath the boat is equal to or less
than the selected alarm depth. The
alarm sounds continuously for about
five seconds, and then intermittently
to remind you that you are still in
shallow water.
Fish Alarm. The Fish Alarm alerts
you to the presence of fish, or other
targets not connected to the
bottom. The Fish Alarm has three
different settings that correspond to
the three different size fish symbols
shown on-screen.
The default setting is “OFF.” With
the “Large fish only” setting, the
105SX alarms on only those targets
that are represented by the large
fish symbols. The 105SX can be set
to alarm on only large and medium
fish, or set to alarm on all fish.
Once the Fish Alarm is
enabled, the 105SX emits an
audible beep when the
selected size fish symbol appears on-screen.
18
USING THE 105SX
MENU FUNCTIONS
Set for large fish only
Set for large and medium fish
Set for all fish