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CONTENTS
General Description 2
Specifications 3
Unit Installation 4
Power Connection 4
Transducer Installation 5 - 8
Operation 9 - 10
Typical Indications 11 - 14
Maintenance 15
Operational Questions & Answers 16 - 20
Transducer Beam Angle Chart 21
Trouble Shooting Chart 22
Accessories and Other Products 23 - 25
Transducers 26 - 27
Service and Support 28
Founded in 1960, Vexilar, Inc. has a long history of bringing revolutionary technology to the
sport fishing industry. Just some of the Vexilar
firsts include: the first liquid crystal display, the
first fish alarm, the first three color display, and
the first CRT and straight line paper graphs, for
the sport fisherman. Now, with the FL-8SLT, we bring you the first true
interference Rejection unit. Again, Vexilar leads, while the others follow.
FL-8SLT Operation Manual
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GENERAL DESCRIPTION
The FL-8SLT is a compact
and lightweight depth
sounder designed for serious
anglers. Besides indicating
depth, the unit also shows
changes in bottom content and
conditions. It can also discriminate between large
underwater targets, such as
fish, and smaller targets such
as bait fish and plankton.
The unit transmits bursts
of high frequency pulses,
which are converted from
electrical to mechanical energy by the transducer. These "sound" pulses
radiate from the transducer downward and are reflected back up to the
transducer where the energy is converted back to electrical signals. The
FL-8SLT then processes these signals and displays them.
The circular display is accomplished by attaching an LED (Light
Emitting Diode) to a wheel, which is then spun at a high speed in the
clockwise direction. This allows for an extremely high speed update.
The bottom, as well as other targets, can be displayed as red, orange, or
green to indicate strong, medium and weak signals respectively. The FL8SLT also has patented Interference Rejection (IR) Technology. This lets
the user "filter out" unwanted interference from another nearby depth
sounder. With two models available, deep and shallow, and a wide variety of accessories to choose from, the Vexilar FL-8SLT is second to none.
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SPECIFICATIONS
Operating Voltage: 10.5 - 15 Volts (12 Volts Nominal)
Current Draw: 200mA
Power Output: 400 Watts (Peak to Peak)
Frequency: 200 kHz
Resolution: 525 Segments
Target Separation: 2.65" Min.
Display Colors: 3 - Red, Orange, and Green
Dimensions: 4.4"H x 6"W x 2.5"D
Weight: 1.1 Lbs.
Depth Scales:
0-20', 0-30', 0-40', 0-60', 0-80', and 0-120' - Shallow Model
Or
0-20', 0-30', 0-40', 0-60', 0-80', and 0-240' - Deep Model
Beam Angle:
If your transducer is not marked, you can determine the beam angle
by the dimensions of the transducer face. Measure the shortest distance
across the face of the transducer. 19˚ transducers measure about 1 1/2”.
9º and dual beam transducers will be about 2 1/2” across the face.
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INSTALLATION
To make the FL-8SLT work, you must provide the unit with power
and mount the transducer in an appropriate location.
UNIT INSTALLATION
Find a convenient place to
mount the unit. This may include
a boat seat, deck, dash, or a
portable case. Make sure that there
is plenty of room for the unit to tilt
and/or swivel freely without the
cables binding behind the unit.
Once you have found a spot,
remove the unit from the gimbal
bracket. Securely attach the bracket to the mounting surface.
POWER CONNECTION
Plug the flat 3 pin connector into the back of the unit. Find the closest source of 12 volts and run the cord to it. Keep the cord away from
sharp metal edges and avoid tight places where the cord may get crushed.
Connect the red wire to positive and the black wire to negative or ground.
If the cord provided is not long enough, more can be added. Use 18 gauge
wire minimum. It is recommended that a 1 amp in-line fuse be placed
in the positive line as close to the power source as possible to protect
against any shorts in the wiring.
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TRANSDUCER INSTALLATION
There are three basic types of transducers to consider: High Speed,
Puck Style, and the Ice-Ducer System.
HIGH SPEED TRANSDUCERS
High Speed transducers are
designed to be mounted on the transom
of a boat. The wedged shape will cut
the water and give a clear depth reading at any boat speed. Locate a spot
similar to the one in figure E. Keep in
mind that you need clear water flow
across the face of the transducer to
insure a clear reading at all speeds. Stay
away from rivets, ribs, or strakes that
would be just in front of the transducer. They will disturb the water and
scramble the reading. Attach the
mounting bracket to the transducer and
hold it up to the boat where you are
planning to mount it (see figure E).
Mark the holes on the transom, or mounting plate, so that when the bottom of the transducer is flush with the bottom of the boat the holes are
located at the bottom of the bracket slots. This gives you room to "fine
tune" the position of the transducer and optimize your reading after
you've put the back boat in the water. Drill out the holes and tighten the
bracket down securely. Be sure to seal any holes drilled
into the transom with silicone to prevent water from leaking into the boat. Run the transducer cord up to the unit
taking the same care as you did when you ran the power
cord. Plug the transducer connector into the back of the
unit and screw the retaining ring down tight.
Figure E
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PUCK STYLE TRANSDUCERS
There are three ways in which a Puck Style transducer can be mounted. It can be mounted In-Hull, on
an electric trolling motor, or portable (with a suction
cup or on an arm of some type).
IN-HULL MOUNTING
This method, gluing the transducer to the hull, gets the same results
as if you were using the High Speed transducer only there are no holes
to drill in the boat and there is no transducer on the transom to get damaged by impact.
Finding the best location for the transducer before mounting is critical. Choose a flat smooth spot near the center of the bilge and near the
back of the boat. It is a good idea to make a "test run" before you permanently install the transducer to make sure that you can indeed get a
reading through your hull, and when the boat is on plane. Put about a
half inch of water in the bilge and hold the transducer in the intended
location. Move the transducer around until you get the best reading.
Mark the spot.
To install the transducer clean the spot of mud and oil. Using an
epoxy or silicone glue make a puddle about the same diameter as the
transducer on the hull. Place the transducer in the glue. Press it down
firmly, gently twisting it back and forth, making sure that there are no
air bubbles in the glue between the transducer and the hull. Let the glue
dry completely before turning the unit on.
Run the transducer cord up to the unit taking the same care as you
did when you ran the power cord. Plug the transducer connector into
the back of the unit and screw the retaining ring down tight.
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TROLLING MOTOR MOUNTING
To attach a Puck Style transducer to a trolling
motor, use a hose clamp or a large cable tie. Notice the
slots in the transducer for this purpose. Locate the
transducer on the bottom of the lower unit as in figure
G. Run the cable up the shaft using cable ties to hold
it in position. Make sure that the movement of the
trolling motor will not damage the cable. Plug the transducer connector
into the back of the unit and screw the retaining ring down tight.
PORTABLE MOUNTING
Optional suction cup brackets can be used to temporarily attach a
transducer to the transom or side of the boat. The cups should be placed
in a location where it will not be torn off when the boat goes high speed.
It is a good idea to tie on a safety rope in case the cup does let go.
There are three suction cup brackets available for the FL-8SLT. The
BK0023 and BK0027 are made to attach the Puck style transducers to a
boat for use at slow speeds. The BK0044 suction cup brackets is made to
attach the high speed transducers to a boat for high speed uses. See page
26 for details.
An arm can also be used to hold the transducer. Simply attach the
transducer to the end of the arm using cable ties or tape. If the arm is
constructed of metal tubing insulate the transducer from the arm by wrapping electrical tape around the arm. This prevents "ringing" which can
be displayed as noise near the surface.
Run the transducer cord up to the unit using cable ties to hold the
cord in place. Plug the transducer connector into the back of the unit and
screw the retaining ring down tight.
Figure G
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THE ICE-DUCER™ SYSTEM*
The Ice-Ducer system provides a quick and easy way to set up the
transducer for ice fishing. All of the adjustments needed to find the true
perpendicular point are done automatically. To use the Ice-Ducer, simply adjust the transducer to the desired depth and drop the assembly in
the ice hole.
There are three main components to the Ice-Ducer system.
They include the transducer,
float, and the stop. The transducer comes assembled with the
connector already installed. The
stop is put on by passing the
transducer cord through the slit
in the side of the stop. Make
sure that the tapered or rounded end is facing down, toward
the transducer. The float is
installed between the stop and
the transducer by, again, passing the transducer cord through the slit in
the side. Make sure the countersunk hole is facing up towards the top.
To use the Ice-Ducer, adjust the stop to allow the transducer to float
at the desired depth. A six inch minimum is recommended in order to
make sure that the transducer will indeed be pointing straight down.
The most it should be down is to the bottom of the ice hole. If the transducer is below the bottom of the ice it can cause tangling problems when
bringing in fish.
If you run into problems when using the Ice-Ducer and you can't see
your bait try this, rub the bottom of the transducer with water to eliminate any residue or air film. This insures good contact between the transducer and the water. Check the length of cord between the float and the
transducer to make sure there are no kinks in the cord that will cause the
transducer to shoot off to the side
*Patent no. 5,546,362
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OPERATION
Figure I shows the three main controls of the FL-8SLT.
They include Power and Range control, Gain, and
Interference Rejection.
POWER AND RANGE CONTROL
The knob located at the bottom of the control panel
turns the unit on and selects which range is to be used.
The center position is the Off position. There are six depth
ranges to choose from.
S1 - 0-20' D1 - 0-30'
S2 - 0-40' D2 - 0-60'
S4 - 0-80' D4 - 0-120'
(D8 - 0-240' Deep Model)
To activate the unit and select the appropriate range turn the knob
to the left or right. To read the correct depth on the display you must
correlate your range setting with the proper scale on the display. Notice
that the shallow ranges are marked in white and the deep ranges are
marked in yellow. For a range selection of S1 you would read the white
numbers on the display. For a range selection of S2 you would read the
white numbers times two, and times four for S4. The same is the case for
the D ranges, only you would read the yellow numbers on the display.
For example, figure J shows the leading edge of the bottom at nine
feet on the white scale. With a range setting of S1 you would interpret
this as nine feet deep. With a range setting of S2 you would interpret this
as 18 feet deep. With a range setting of D1 you would look at the yellow
numbers and read the depth as slightly over 13 feet deep. D2 would read
26 feet. A setting of D4 would read the depth at 52 feet (13 x 4).
Figure I