Humminbird LCR4 X6 User Manual

Before attempting to install or operate your Humminbird LCR it is recommended that you read the
operations manual thoroughly. The LCR has a number of special features not found on any other
depth sounder. Therefore, to completely understand all the features we suggest you follow the
instructions in this manual. If, after reading the instructions, there is something you do not
completely understand about the operation of your unit, we recommend you contact our
Customer Service Department -CALL

334-687-0503
Our Customer Service hours are Monday - Friday 8:00 A. M.-5:00 P. M.
Please complete your warranty card and return it to us immediately.

Thank you.

INTRODUCTION
Congratulations on selecting the LCR4x6. Your new Humminbird LCR incorporates the most

advanced, innovative concepts in sonar equipment. The LCR is probably the most intelligent
depth sounder ever created. Advanced microcomputer technology is used to simplify its
operation, not complicate it, so you can quickly learn the basics of operating your unit. You will
find even the advanced features, such as Split Screen Zoom and Screen Memory, are easy to
learn and fun to use.
Your Humminbird LCR has a number of outstanding features including a unique automatic
feature. This computer-controlled feature, pioneered by Humminbird, makes using your LCR as
simple as pushing the “Power” button. The computer will automatically adjust the sensitivity,
change the depth scale even if the bottom goes off the screen and black out everything below the
bottom to make the display easy to read.
The LCR4x6 control panel is another Humminbird innovation. You have complete control of all
the unit’s features with just seven buttons and an easy-to-understand display of all adjustments is
right on the screen. You will quickly see that the advanced technology of the LCR4x6 is easy to
use and understand.
Other features include Split Screen Zoom and Bottom Lock, Screen Memory, Total Screen
Update, large digital bottom depth readout, Fish Alarm, Bottom Alarm, and optional Surface
Temperature and Speed Gauges for readings on the LCR screen.
The LCR has a large 6-inch by 4-inch visibility LCD, a night -light, waterproof enclosure, and a
low profile swivel mount. Read this operations manual thoroughly to get the most from all the
LCR’s features. You’ll have fun learning to use your LCR4x6 and it will give you many hours of
fishing and boating pleasure.

THEORY OF OPERATION
You Humminbird LCR works on the basic principle of sonar. An electronic signal is generated

within the control head of the unit. When coupled to the transducer, this signal is converted to an
ultrasonic signal and is transmitted toward the bottom. The speed of the ultrasonic signal
travelling through the water is approximately 4800 feet per second.
The signal travels through the water until it strikes an object or the bottom. At this instant it is
reflected back, picked up by the transducer, reconverted to an electric signal and is recorded on
the display of the LCR.
The reading at the far right position of the screed shows what is being passed over at that time.
As new information is received, the old information is shifted to the left and the new information is
added. The information is retained until it disappears from the left side of the screen. Figure 1
illustrates a typical display.
One of the unique features of your LCR is the Split Screen Zoom with Total Screen Update.
Figure 1 shows a Split Screen Zo om display with the full depth range information on the right and

the expanded view on the left. The Total Screen Update feature is explained in detail later, but
basically with the Zoom the Total Screen Update allows you to zoom in on an area even after you
have passed by it. The display resolution on the expanded portion of the screen is as good as ¾
inch per dot, giving you exact detail while still viewing the full depth range information on the right.
The display technology used on the LCR4x6 has been pioneered by Humminbird. The display
uses Advanced Super Twist Liquid Crystal Technology for the best contrast, widest viewing angle
and extreme high and low temperature operation.
The Super Twist Liquid Crystal material in the display is a liquid that can be aligned such that it
either “blocks” light or it lets light pass through. The “blocking” of light is what makes the black
dots on the screen.
Since the LCR’s display depends on light passing through it to make the images, increasing the
light source will make it easier to see. This is why your LCR can be seen so well in direct sunlight.
You will also notice that the display can be seen better at certain angles. The LCR mounting has
been designed for tilting and pivoting so that you can easily maint ain a good angle for viewing.
Another characteristic of an LCR display is that you may find that some polarized glasses might
affect the view by causing a rainbow prism to appear. This condition can possibly be improved by
a slight adjustment in tilt.

SPLIT SCREEN OPERATION
The LCR4x6’s split screen feature will allow you to make side-by-side comparisons. You will be

able to split the screen and compare actual, full depth scale information with three functions -1.)
Zoom, 2.) Bottom Lock, or 3.) Screen Memory.

The use of the split screen is very easy. Whenever any of three functions, Zoom, Bottom Lock,
or Screen Memory, is turned on the screen automatically splits.

LEFT HALF OF SCREEN RIGHT SIDE OF SCREEN
SHOWS
SHOWS EXPANDED VIEW, IN FULL DEPTH RANGE, IN THIS
CASE
THIS CASE FROM 18 FEET TO FROM 0 TO 60 FEET
33 FEET

When Zoom is activated, for example as shown in figure 2, the left half of the screen any shows
the expanded information while the right half shows the full depth scale information. The Zoom
range can be moved up or down to search out any area. Even the depths of the upper and lower
part of the Zoom region are digitally displayed for precise location of fish and structure.
The bottom lock and screen memory work in the same way to give you the benefit of split screen
comparisons. The detailed operation of each of these functions is explained later in this manual.

TOTAL SCREEN UPDATE
Total Screen Update was invented by Humminbird engineers. You will find this unique feature

very useful and beneficial. It will allow you, when changing depth scales, for example, to totally
change the entire screen to the new depth scale. It will also allow you to ZOOM in and look at
information in much finer detail even after you have already gone over the area.

HOW DOES TOTAL SCREEN UPDATE WORK?
Memory devices inside the LCR4x6 can store hundreds of thousands of bits of information

Automatically, while you are operating the unit, the computer is putting information into the LCR’s
memory.
All this information is being put into memory in much smaller increments (pieces) than is being
displayed on the normal full depth scale. For example, on the 0 to 30 foot range-each dot is
equal to 3 inches, or on the 0 to 60 foot range each dot is 6 inches, and so forth. But in the
LCR4x6’s memory information is being stored such that when you Zoom in on a 71/2 foot
increment each dot represents an incredible ¾ inch per dot.

HOW TO USE TOTAL SCREEN UPDATE
It is very easy to use Total Screen Update because the LCR’s computer will do everything

automatically. You will notice how Total Screen Update works when a depth range changes.
When the bottom display goes off the screen, The LCR4x6 will automatically change to the next
deepest range and update the entire screen to the next deepest range and update the entire
screen to the new depth range. This Total Screen Update feature also works when changing to
shallower scales. For example, suppose you are in the 0 to 120 foot scale but the bottom depth
changes quickly to 20 feet. When the depth range is changed to the 0-30 foot scale , the entire
screen will look just as if you had gone over the area on the 0-30 foot scale.
Another way that you will use Total Screen Update is in operating the LCR’s Zoom or Bottom
Lock. Since the computer has stored in memory information in very small increments, you will be
able to recall this information from memory to get an expanded view of areas which you have
already passed over.
For example, if you go over some interesting structure or fish, you will be able to Zoom in for a
closer look without going back over the area by simply activating the Zoom. The information that
is stored in memory will automatically be recalled and displayed on he left side of the screen. The
operation of Zoom is explained in a later section.

The high visibility readout of the LCR allows you to see fish, bottom contour and underwater
structure.

The LCR is designed to operate with a standard 16 degree transducer included with the unit.
Other transducers, such as 32 degrees, cannot be used. In order for your LCR to operate well at
high speeds, you must have a properly mounted transducer. Please read the transducer
mounting procedure carefully.

TRANSDUCER MOUNTING PROCEDURE
Humminbird’s high speed transducer is supplied with your LCR. This transducer has been

designed to give good high speed readings on most all boat designs, including aluminum.
Please carefully consider the following before installing your transducer.

TRANSDUCER MOUNTING OPTIONS
A. Transom Mount - The Humminbird high speed transducer allows the transducer element to be

mounted below the bottom of the boat hull keeping the transducer out of turbulent water and
insuring good high speed operation. The transducer will absorb the blow of any obstruction
by rotating up out of the metal spring bracket without harming the transducer, or your boat.
The transducer can be re-engaged by simply rotating the transducer down and snapping it
back in place. (See Figure A)

B. Inside Hull Mount - The high speed transducer can be mounted inside the hull (without pivot

assembly) using the proper two-part epoxy, such as Humminbird’s epoxy kit. Even though
there is some loss of signal in shooting through the hull, your LCR will perform well with this
type of installation. You cannot shoot through the hull of an aluminum boat.

C. Trolling motor Mount - This type of transducer is not supplied with your LCR. It is designed to

mount on the foot of a trolling motor. You may exchange your un-used high speed
transducer for a trolling motor transducer. Call the Humminbird Customer Service
Department.

D. Bronz Thru-Hull Mount - This transducer is not supplied with your LCR but for an additional

cost you may exchange your un-used high speed transducer for a bronz thru-hull. The bronz
thru-hull transducer has a threaded stem which installs through a hole drilled in the boat hull,
leaving the housing exposed under the boat. This type of installation must be used for many
boats with in-board engines, because there is no suitable location on the transom away from
the noise and turbulence created by the prop. A bronz thru-hull transducer should be installed
by qualified personnel only.
The LCR will operate well at high speeds with a properly mounted transducer. Remember, a
transducer will not work transmitting through air or through air bubbles.

1. TRANSOM MOUNTING PROCEEDURE

Step 1.
MOUNTING LOCATION- It is important that the transducer be mounted on the transom where
water flow is in constant contact with the transducer. You may wish to observe the rear of the
boat while it is moving through the water to determine the best mounting location.

Step 2.
BRACKET INSTALLATION (Aluminum Boats)- To install the metal bracket on an aluminum boat
locate the template on the transom between rows of rivets, or ribs that are on the bottom of the
boat. Align the template so that the bottom corner of the template nearest the center of the
transom is on the bottom edge of the transom.

Once the location is determined mark and drill three 7/64” dia.. holes noted on the template.
Attach the metal bracket using three #10 self threading screws supplied. Be sure to align holes in
the center of the
Bracket slots. On some aluminum boats it may be necessary to use a wood back-up plate. It is
important to use a silicone sealant between the screwhead and bracket in order to preve nt
leaking. (See Figure C)

Step 2.
BRACKET INSTALLATION (Fiberglass Boats)- If your boat has a stepped transom located
below and under the main transom, the compact transducer design allows mounting in this area.
This mounting location is recommended for good reading at very high speeds. (See Figure D)

To install the metal bracket on a fiberglass boat, locate the template on the transom in the same
manner as for an aluminum boat. (See Figure C)

NOTE: On boats with more than 15 degree deadrise angle it may be necessary to mount the
transducer slightly off parallel with the water level. (See Figure E)

Mark and drill the three 9/64” dia. holes as shown on the template. Attach the metal bracket using
the three #10 self threading screws supplied. Be sure to align the holes so that they are centered
vertically in the three slots found in the bracket. It is important to use a silicone sealant between
the screwhead and bracket in order to prevent leaking.

Step 3.
TRANSDUCER PIVOT ASSEMBLY - Assemble the pivot to the transducer main body using the
two ¼”x5/8” allen head screws, two 3/8” tooth washers and two, ¼” square nuts. Make sure the
tooth washers are sandwiched between the transducer main body and the pivot. The square nuts
are trapped inside the pivot and will not rotate as the allen head screws are tightened.
HOWEVER, DO NOT TIGHTEN AT THIS POINT. (See Figure F)

Step 4
TRANSDUCER ASSEMBLY - Insert the transducer assembly into the metal bracket from the
bottom. Push up until the holes in the plastic pivot align with the uppermost holes in the bracket.
Slide the O-ring on to the headed pin and insert it through the two parts. Assemble by screwing
the ¼”x3/8” allen head screw into the end of the pin and tighten. (See Figure G)

Step 5
ANGLE ALLIGHMENT- Set the transducer angle so that it is parallel with the bottom of the boat
hull. Once proper alignment is achieved, tighten the two allen head screws using the 5/32” allen