Lowrance X-1550 User manual

LITHO IN U.S.A. 988-0083-08
INSTALLATIONAND OPERATIONMANUAL
MODEL X-1550
GRAPH RECORDER
•LOWRANCE ELECTRONICS,INC.
12000 E. SKELLY DR.TULSA, OKLA. 74128
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Figure44
- (1 ...-
—r
Il-i
High Speed (46 M.P.H.) Figure45
SUPPRESSION: ON— ADEQUATE SETTING
SENSITIVITY: ON— 1/2 POSITION
a r
•!'• - aaYr, '1
- -
¾ - .
iii:-. . —
• a.
RANGE: 0TO80 FEET SENSITIVITY: 3/4 Figure46
PULSEWIDTH: 100 MICRO-SECONDS LINES:OFF
SUPPRESSOR: MINIMUM PAPER SPEED: MAXIMUM
21
High Speed (46 MPH.)
SUPPRESSION: OFF
SENSITIVITY: ON 1/2 POSITION
NOTE POOR RECORD CAUSED
BY NOTUSING SUPPRESSION
WHENATHIGH SPEED.
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preventsounding.
INDEX
HowItWorks
20 1
Example: Setthe initial transmitter ducer Face with soapand water
pulse
width tolOO toremove anyoilfilm that may
micro-seconds. collect.Oiland dirtonthe face
Press:1 0, 0,then SCALES and willreducesensitivity ormayeven Introduction 2
LINEStogether 2
SPECIFICATIONS — X-1550 GOTA PROBLEM? LET US j Installation 3
Depth Ranges:
Feet, fathoms, meters.
Operating Frequency:
HELP!
Ifyou have a problem withyour
sonar unit, please give us a Basic Operation
Suppressor 4
5
50 kHz(50,000 cyclesper
second); accuracy iswithin0.6
percent.
chance tohelpbefore sending it in
forrepair.
Assistance canoften beex-
Paper Speed
®
GRAYLINE 6
6
Pulse Length:
(duration of pulse):200-l000gs
(30-2000ps programable)
tended bytelephone or letter.
Write orcall one ofourAuthorized
Service Centers orthe Lowrance
Range .
Lower Limit 7
7
OperatingVoltage: Electronics, Inc., Customer Ser- Upper Limit 8
Minimum:10 volts DC
Maximum:15volts DC vice Department in Tulsa,OK.
(Toll-free1-800-331-3889). Lines 8
OperatingCurrent: Please detailthe problem you Marker 8
0.7to1.8 amps depending on
printing density and output
power.
are experiencing. Our Service De-
partment maybeableto saveyou
the inconvenience ofreturning
Scale ....
End Of Paper 9 9
Output Power:
1600watts typicalpeak-to-peak.
(200watts RMS)
your unit.
Ifit isdetermined thatyour unit
must be returned, full shipping in-
HowTo Read Graphs
.
Paper Loading
10
10
Weight:
8.5lb. (3.9Kg)
Dimension:
structions will be provided.
SCHEMATIC DIAGRAMAND Stylus Replacement
Dosand Donts 14 16
With Gimbal Mount:
Width -12¼"
Height - 8%"
Depth -51/4" ,.
Width - 91/2"
Height-71/2"
Deth- 51/4"
V
PARTS LIST .
Should you desire aSchematic
Diagram and Parts listforyour
Lowrance TRUELINE RECORD-
ER, send $1.00to PARTSLIST,
Lowrance Electronics, Inc.,12000
East Skelly Drive,Tulsa,OkIa-
homa 74128. Be sure andgive us
the Model Numberand Serial
Troubleshooting
Advanced Operation
Surface Clarity Control (5CC)
ee, a oms, eers
Transmitand Print Alternate
.
Transmitter PulseWidth
16
16
16
7
17
17
NOTICE Number ofyour
SONAR Specifications 21.
Periodically wash the Trans- INSTRUMENT. Service Information 22
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IINTRODUCTION example, with theLOWER LIMIT transmitter pulse
width isselected,
TheLowrance X-1550is a
highly sophisticated recording
depth sounder.Thanksto amic-
rocomputer, theX-1550 cando
morethan anyotherdepthsoun-
derinits price range. Full control
ofthesystem is atyourfingertips
to meet the changing demandsof
varying bottom conditions, water
depth and boatspeed. Youcan
selecttheunit's
sensitivity setting,
suppression level, depth range,
paperspeed, andthedegree of
"Gray Line".usedtoenhancethe
recorded information:Thepat-
ented Lowrance variable
suppres-
sion system notonlyfiltersout
falsesignals without
distorting the
real ones, butis synchronized
withthegraylinefunction to pro-
vide clearsignals under all condi-
tions.Thepermanent record of
whatyour sonarhas "seen"is
rolled and storedinsidethecase.
Small boat sonarsystems are
routinely used tomeasure water
depth,examine bottom contours,
andlocatefish. The capability of
theX-1550 goesfarbeyond the
ordinary.Cluestothecomposition
ofthe bottom are given
— schools
ofbaitfishare easilydistinguished
from solitary game fish —thereis
acontinuousdisplay ofinformation
about bottom contours and sub-
merged shipwrecks — fish closer
together
than sixinches canbe
shown separately — concentra-
tionsofalgae, moss orplankton
canbe identified — attrolling
speeds individual fishare com-
monly recorded with acharacteris-
tic"arched"
signature whichdis-
tinguishesthem fromtheirsur-
roundings — layers ofwaterwith
differenttemperatures canbede-
tected undergood conditions, and
vertical movement offish, (up or
down), can beshown.
HOW ITWORKS
When theunit isturned on, an
electronically regulated motor
drives a lightweight beltlocated at
the right edge ofthe recording
paper.Themarking stylusis at-
tached tothis belt. When the
stylusisatthe topofthe papera
small mark is made. This iscalled
the zero mark, and represents the
surface ofthewater.
setto 260 feet, theinitial
transmit
pulse
width would be260
ts. IftheLOWER LIMIT issetto
390 feet, the initial transmit
pulse would be390Its. Finally,
from 600 feet and below,the
initial pulsewidth remains at600
micro-seconds.
Thetransmitter pulse width can
beincreased fromthe initial point
atanytimeby rotatingthe Sup-
pressor control clockwise. The
maximum amount ofpulse width
added totheinitialtransmitter
pulse width is approximately 800
microseconds. Inotherwords, if
the LOWER LIMIT is setto420
feet, and the Suppressor con-
trol is rotatedtothe maximum pos-
ition, thetransmitter pulse
width
would be1220 micro-seconds.
(420initial+ 800 =1220.)
Earlier,wetalked about the rela-
tionship between pulse
width and
target separation. As pulse width
increases, targetseparation or
resolution isdegraded. However,if
thepulse width isdecreased,
resolution becomes much better.
TheX-1550 allows
youtotake
advantage ofthis fact by making
it possibletooverride the initial
transmitter pulse width selling
fromwhatthemicro-computer
selects according totheLower
Limit.
Theinitial transmitter pulse
width canbe setfrom30 ps to
2000 jisby entering itonthe
keyboard as shown below.
Noothergraph in themarket
today can give youthisfeature.
Aftersetting theinitialtransmitter
pulsewidth, the suppressor con-
trolcan still be used tocancel out
noise byincreasing the pulse
width.
Forexample, ifa50 tsinitial
and theSuppressor controlis ro-
tated tomaximum, the transmitter
pulse
width would be 850 j's.Re-
turning
theSuppressor control to
minimum will restoretheunitto a
50/.tstransmitter pulse width.
TheX-1550 willdisplaytheinitial
transmitter pulsewidth atthe bot-
tom ofthe paper when you over-
ride themicro-computer.Todistin-
guish
theinitialtransmitter pulse.
width fromthe depth scale printed
onthe paper,a zero is printed in
frontofthepulse width sothatthe
twowillnotbeconfused. For
example, a100 j'stransmitter
pulse
width will be displayedon
thepaperas 0100. A50Its
transmitter pulsewidth would be
displayed as0050, while a50-foot
depth will be displayed as50. To
setthe initial transmitterpulse
width, simply press the amountof
pulse
width desired onthe
keyboard, and then press both the
LINES and SCALES keysatthe
same time. (Note: Ifthelines
and/orthescales were turned off,
this willturnthem backon.Toturn
them backoffagain, presseither
the SCALES key orthe LINES key
independently.Do notpressthem
simultaneously.)
Thiswill overridethe micro-
computer's selection and setthe
initial transmitter pulse width tothe
desired setting. (Note:When an
initial transmit
pulsewidth isset,
thiswidthwill befixedforall depth
settings until changed or untilcon-
trol is returned tothemicro-
computer.)
To returnthe unittothecontrol
ofthe micro-computer,simply
press 0 and then the LINES and
SCALES keys atthesame time.
Thiswill revert the unitbackto
normal operation.
Figure 1
Fish: 17 ft.
Depth: 35 Ft.
TRULINERECORDER BOTHSEND AND RECEIVES SIGNALS.
RECEIVED SIGNALSARE INDICATED ON GRAPH PAPER.
2 19
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used onallthe Lowrance's vari-
able suppressionflashers and
graphs. Basically,itworks on the
principlethat most noisepulses
are ofrelatively shortduration. It
the receiver circuit canbead-
justed
so thatitwillacceptonly
long pulses, then the shortpulses
will be cancelled out, and only the
desired information (fish, bottom,
structure, etc.) will bedisplayed.
Of course, thetransmitter's pulse
width would have to be increased
atthesame time sothatthe return
echoeswould beaccepted bythe
receiver.
This isexactly whatthe Low-
rance suppressionsystem does.
Thetransmitter's pulse width is in-
creased bythe frontpanel sup-
pression control, and thereceiver
'tracks" the amount ofincreased
pulsewidth, cancelling outany
narrow noise pulses, and display-
ing only the returnechoesfrom
fishorthebottom, etc.(Note: Re-
ceiver sensitivity is notdiminished
atallbythis process.)
Theonly disadvantage tothis
system isresolution, or theability
toseparate targets, isdiminished
whenthe pulsewidthis in-
creased. A200 ps (micro-sec-
ond)transmitter pulse
width used
ontheX-1550 when
powerisfirst
turned on, willallowthe unitto
display two fishortargets
thatare
only 6inches apart. Inother
words, iftwofish thatare six
inchesapart aredisplayed onthe
graph paper,theywill show up as
twoseparate arches whenthe
transmitter isoperating with a200
ps pulse width. Now, ifwein-
crease thetransmitter pulse width
to400 Ps, (byrotating theSup-
pressorcontrol clockwise) those
same twofish archeswill blend
together andshowupas one fish
orpossibly even a "blob" onthe
paper.
Witha400 tts transmit
pulse
width, those same two fishwill
have to be at least12 inches apart
beforetheywill show upas two
separate arches onthegraph.
Thisiswhy itis important to leave
the Suppressor control turned
downto minimum when looking
forfish.
However,itishelpful sometimes
tohavelongerpulse widths when
noise isnotaconcern. When
using a sonar in deeper water, it is
easier forthe unittodetecta
longerpulsecoming backfromthe
bottom orfromthefish. Thisis
called "Probability of Echo Detec-
tion."Theprobability ofthe unit
being abletodetectan echore-
turning from deep waterisdi-
minished because thefurther the
sound pulse hastotravel, the
weakeritbecomes. By broadening
the pulsewidth, in essence, a
largersignal istransmitted and it
is easier forthe receiver todetectit.
Forthisreason, themicrocom-
puterin theX-1550 automatically
increases theinitial pulse widthof
theunit asdeeper lowerlimIts are
setby theoperator.(Note: Initial
pulse
width isthepulse widthof
the unitwhentheSuppressor
control isturned tominimum.)
INITIAL
TRANSMIT
LOWER PULSE
LIMIT WIDTH
(Feet) (Micro-seconds)
10 110
20 130
30 160
40-200 200
From 210 feetto600feet,
theinitialpulse width increases at
thesame rateas thedepth. For
Figure 2
Thestylus continues to move
down theedge ofthe paper
while
thesound pulse istraveling
through thewater,and whenan
echo isdetected, thestylus makes
another mark onthepaper. The
depth ofthe object which reflected
the echo can be read infeet by
comparing its locationon the
paper to the depth scale printed
onthe paper.
Avariable speed motor drives
the paper graph. (The paperis
treated sothatthe stylus will burn
itto leavea
permanent
black
mark.) During one revolution of
thestylus belt, averynarrow mark
will be made bythe flexible stylus,
butthe paper will move asmall
amount beforethe next revolution.
Each mark will blend into the one
before, so that acomposite "pic-
ture"ofthetarget will be made,
onetiny mark atatime.
Duetothe manyfeaturesthat
this unit has,wehavesplitthe
operation section ofthismanual
intotwo sections. Thefirstsec-
tion,Section III, isentitled "Basic
Operation" andcovers everything
that isabsolutely necessary to
usethe X-1550isawidevariety
0 ofsituations. Itwilltellyou howto
usethebasic controls —Sen-
sitivity,Suppressor, PaperSpeed,
Grayline, Range, plus afew spe-
cialfunctions.
Thissection will beadequate
for most situations. However,
onceyouhave mastered the ba-
sicoperation oftheX-1550 as de-
scribed inSection III, you may
wishtotrysome ofthefeatures
described inSection VI—Ad-
vanced Operation. Thischapter
will explain fourotherfeatures
thatwill enable theserious
operator
to get themaximum use
outofthisequipment.
Weurgeyou to read thisman-
ualthoroughly and familiarize
yourself withthe controls. Al-
though this is avery advanced
unit, it iseasyto use, thanksto
the powerofthe microcomputer
and thefrontpanel controls.
Should yourequire extrahelp,
please phone ourCustomer Ser-
vice Department toll freeat
1-800-331-3889.(Oklahoma resi-
dents call collect -1-918-437-
6881).Aservicerepresentative will
be happy to helpyou.
II INSTALLATION
Mounting —
The depth sounder maybe in-
stalled in anyconvenient area,
provided the unitcan betiltedfor
the bestviewingangle. Fourholes
in thebracket base allowwood
screw orboltmounting. Awood
stiffener
maybe required on the
GRAPH
PAPER
-—---- PAPER QJ—PULLEV
TRAVEL
18 3
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backofthinfiberglass panels to
support theX-1550.
Ifthedesired location is closer
than 18:: to amagnetic compass,
atrialrun should be madewith
theunit in operation to be sure
thatthecompass readings are not
affected.
Figure 3
BESURE to insert
thetwo rub-
bergrommets on gimbal bracket.
Thelargerside (larger diameter)
ofgrommet goeson inside of
gimbal bracket sothat itis sand-
wiched between gimbal
bracket
and sonarinstrument (seedraw-
ings). Thegrommets provide fric-
tionto hold the unitatthedesired
angle.
PowerConnections—
Twelve voltDC power forthe
depth soundershould besupplied
by theboat's12-volt electrical sys-
tem. Thepowercablemay beat-
tached toan accessory or power
buss, but ifyou have problems
with electrical interference, the
cableshould beattached directly
tothe battery.
Ifalonger
cableis required, use
ordinary#18 lampcord available
atanyhardware or electronic sup-
ply store. Splices should besol-
dered. Ifthiscan'tbedone, use
crimp-type splices. Tape allsplices
with electricaltape.
An in-line fuseholderwith fuse
issuppliedwiththeX-1550. Be
certain toinstallthisfuseholder
asclose tothe power source as
possible.Thiswill protect both
thesonar unitandthepower
cableintheevent ashortoccurs.
Crimp connectors are supplied to
attachthefuseholdertothe
powercable. Theredorwhite
wirein thepowercableisthe
positiveconductor.Theblackwire
isthegroundconductor.
Thegraph isprotected fromac-
cidental polarity reversals and no
damage will occurifthewiresare
reversed. Theunitwillnotoperate,
however, untilthe proper polarity
isapplied.
Ill BASICOPERATION
On-offand SensitivityControl—
RotatetheOn/Off knob clockwise
toturntheuniton.TheSensitivity
knob works much likethe volume
controlonaradio, thatis, weaker
signals will bedetected with
highersettings ofthe knob. When
cruising: oratothertimeswhen
justsimple bottom-contour infor-
mation isdesired, the Sensitivity
setting canbe low. Indeepwater
orover soft, muddy bottoms,
(which produceweakechoes), the
setting will have to be higher.
mediately beseen. Use onlythe
amount of SCC required to reduce
theclutter, as fish signals canbe
eliminated also.
Toturnthe5CCfunction OFF,
press 0, MARK/SCC. The SCC
value(1, 2, or 3) canbe changed
orturnedOFFatanytime.
Feet,Fathoms,Meters
TheX-15will display thedepth
in feet, fathoms, ormeters. Al-
though the unitwill revertbackto
thefeet mode whenever power
isturned off, itis simple tochange
to any modeyou wishby pressing
1 and 3forfeet— 4and 6 for
fathoms, and 7and 9formeters.
These keys must be pressed
simultaneously forthis featureto
work.
When the unitis in the Feet
mode, onlyone Uwill be dis-
played atthe bottom ofthe chart
paper every fewinches. In the
FathommodetwoU'swill bedis-
played. Three L's
will be printed
onthe Meter mode.
Example: Display Meters
Press: 7 and 9 simultaneously
Result: Figure 41
El 0—
,8
- 12 -
- lb -
20—
13y looking atthenumberof
U 's, one candetermine the
depth display mode thatthe unitis
in, i.e., Feet- U , Fathoms -
Ii
U, orMeters
-I.!UU.
Transmitand Print Alternate
When theX-1550isfirstturned
on,theTransmitand PrintAlter-
nate function isenabled automat-
ically.Thiscauses thestylus
to
printonevery
otherrevolution
andthetransmitter isalso trig-
gered onevery other revolution.
Thisaccomplishes three things:
1. Sincethe stylus only prints ev-
eryotherrevolution,the re-
corded information isnot
squeezed together into avery
small area. Thisallows better
records atslower paper
speeds. Also, thescale num-
bersare spread outmore, so
theyare more legible.Thepa-
perspeed isalso slowed down
slightly.
2. Preventsthe possibilityof
'wrap
around". Thisisthe un-
desirable occurrence ofthe
second orthird bottom echo
printed on thepaper atthetop
ormiddle ofthepage. Many
timesthis can interferewith
fish orother
targets thatyou
wishtosee.(See Figures46
and 47.)
3. Reduces thereverberation ef-
fect.Thishappens mainly on
lowerfrequency units,al-
though
itdoessometimes
— showupon high frequency
graphs.
TodisabletheTransmitand
— Print Alternate mode, press the
UPPER LIMITandLOWER LIMIT
2 — keyssimultaneously.Ifyouwish
toturnthefunction backon,sim-
lb — plypress the UPPER LIMITand
LOWER LIMIT keys again.This
will cause theunittotransmit and
print oneverystylus rotationand
speeds
thepaper upslightly.
TransmitPulse Width
Thenoise suppression system
intheX-1550isa patentedpulse
width discrimination suppression
circuit,and isthe same asthe one
- LI
Ground
(Negative)
Figure 4 4 17
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mountedonthetransom should
bewashed periodicallywith mild
soapy water to remove anyac-
cumulatedroadgrime or oilyfilm.
This is essential to have good
contact betweenthetransducer
and thewater.
Periodically,
the rubber roller on
thepaper drive should be cleaned
with aclothdampened with al-
cohol, to improvethefrictionon
thedrive shaft. (Seepage 16,
Figure29).
DO SECTION
Do carry aspare fuse,sty/us
belt,and rollofpaper.
Do usethetapefrom anew roll
orpaper toattach ittothetake-up
spool.
Do usetheempty cardboard
core from the last roll ofpaperon
thetake-up post.
Do carrya penciltomake notes
onthe paper.
Do keep the recorded graphs
forfuture reference.
Do clean the stylus beltand
wheels with alcohol afterevery
fiverolls ofpaper.
DON'T SECTION
DON'T OPENTHE.CASE
WHEN THEUNIT ISON.
Don'tpull the platen assembly
down whenthestylusisatthe
front.
Don'tstore anyobjects inside
thecase or behindthe viewing
door.
Don'tforget totapethe paper to
thetake-up core.
Don't rotate thestylus beltup.
Don't use oily cloths, strongsol-
ventsorabrasive cleansers.
TROUBLESHOOTING
Symptom
On/Off
switchis ON", butthe
stylus and paper don'tmove.
WhatTo Do
Checkfuse;check connections 16
atbattery; tighten power cord
connector,
Symptom
On/Offswitch is 'ON", have
zero mark, but no echoes or bot-
tomsignals.
WhatTo Do
Besure thetransducer is
plugged intothe unitand the
transducer isincontact with the
water.
Symptom
TheunitisON, but paper does
not move.
WhatTo Do
Tape Papertocardboard spool
ontake-uppost.
Symptom
Recorder marks are faintor dim.
WhatTo Do
Clean viewing door;replace the
stylus; checkbattery connections.
Sympton
Recorded marks are very
heavy; paper istornby stylus.
WhatTo Do
Bend the stylus slightly to re-
duce pressure on paper.
VI ADVANCED OPERATION
SurfaceClarity Control (SCC)
Thesurface markings atthetop
ofthechartpaper can, attimes,
extend many feetbelowthe sur-
face. Thisoften interferes with the
areathatoneistryingto graph.
Surface clutter is caused byalgae
and plankton, airbubblescreated
by wave action or boat wakes, bait
fish, ortemperature inversions.
The surface clutter can be re-
duced oreliminated by using the
MARK/SCC
key onthe control panel.
To use theSCC, control, press 1
for minimum effect, 2for an inter-
mediate control, or3for maximum
elimination ofsurface clutter, and
then press MARK/SCC. Areduc-
tionofthe surface clutter will im-
When high Sensitivitysettings
are used, a second bottom echo
will appear.This is normal and is
caused bythe returning signal re-
flecting
offthe surface ofthe wa-
ter, making asecond triptothe
bottom and back.
When detailed information about
brush piles, individualfish orthe
thermocline isdesired, the Sen-
sitivity knobshould besetatabout
¾ point. Refertothe illustration
below toseewhateffecttheSen-
sitivity settinghas on the recorded
information.
Recording individual fishwith an
"arched"
signature canusually be
accomplished attrolling speed
withtheSensitivity knob atthe3/4
point, or higher.Refertothe sec-
tion"Arched Signatures," onpage
10for more information about this
important function ofyour
recorder.
Suppression Control
TheSuppression Control is
used to reduce interference from
noise. Noise, inelectronic
terms,
isany undesired signal. Itcan be
caused byan electrical source,
(such asthe engine's ignitionsys-
tem),or by airbubbles in dis-
turbedwaterwhich is called cavi-
tationnoise. In both cases, the
noisecouldproduce unwanted
marks onthe paper.(SeeFigure
44 &45.) Fortunately, noise
pulses
are relatively shortin timecom-
pared toreal sonar signals. Ad-
vancing
the Suppression knobwill
causethe system to reject these
unwanted, short pulses without
reducing the sensitivity in anyway.
Thispatented design is exclu-
Figure 6
12
I ,
Figure 7 SENSITIVITY: TOOLow Figure 8 SENSITIVITY:
PROPER SETTiNG
5
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sivewith Lowrance. However;with RANGE PAPER SPEED STYLUS
BELT REPLACEMENT
high suppression settings, the
graphrecord becomes coarse and
the ability toseparate fishfromthe
bottom orfromotherfish will be
decreased. (See Figure 10.)
Therefore, the lowerthesuppres-
sion setting, the better.Advance
the knob setting onlyas far as
chart paper when
operating in
deep water.Thechartbelow gives
the points wherethemaximum
speed ofthe paperisslowed.
necessary to remove theerratic,
unwanted noisemarks. Mostof
thetime at lowortrolling speeds,
no suppression will beneeded.
PaperSpeed Control
Thisknob adjusts the speed of
the chartpaper Forgood detailed
graphs, in shallow to medium
depths, turnthe paperspeed con-
trol uptoat least3/4 when
trolling.
Forbestdetails, turnitupto
maximum. Thiswill show proper
fisharchesatlow speeds and
keepshigh speed information from
beingcompressed. Thepaper
speed should beturneddown
whenusing theunit in deep water.
Thiswill prevent gaps fromap-
pearingin the record. In fact, the
microcomputer willautomatically
slowthemaximum speed ofthe
even furtherby adjusting the
paper speed control. Remember; if
gaps appearin the record, turn
the paper speed downuntil asolid
record is achieved. Thepaper
speed mayalso be slowed when
not looking forfishorto simply
conserve paper.
GRAYLINE On/OffKnob
TheGRAYLINE®functioncan be
used to outline the bottom contour
which might otherwise be hidden
Leneathtrees and brush; itcan
also give clues-to thecomposition
ofthe bottom. Ahardbottom re-
turnsa verystrong signal causing
awide gray line. Asoft, muddy or
weedy bottom returns aweaker
signal which is emphasizedwith a
narrow gray line. Do notadvance
thecontrol toofaroritwill gray
CAUTION —High voltage is
presentintheelectronicsection
whentheunitisturnedon.
1. TURN
THE UNIT OFF.
2. Release both catchesonthe
topofthe case. Pull outand
downonthetop ofthe case
fronttoexpose thestylusbelt.
3. Thestylus belt rides overtwo
wheels located atthe right
edge ofthe platen assembly.
RefertoFigure 2 on page 3.
Move thefrontofthebelt
DOWN to position the stylus
atthecenterofthe platen.
4. Grasp the beltatthestylus
holder withthethumband
forefinger and move itgently
totheleft while pushing the
beltoffthewheels withthe
other
forefinger. (SeeFigure
40.)
5. Position thenewbeltonthe
wheels by reversing thepro-
cedure usedto remove the
oldone. BESUREthe fingers
ofthe new stylus are pointed
6. Close thefrontofthe case.
Latch both catches onthetop
ofthe unit.
MAINTENANCE
NOTE:Thestylus maybe dam-
aged ifitisin frontofthe platen
whenthe platen assembly is
pulled down. A/ways movethe
stylus tothe backside ofthe
platen when changing the paper
rolls. Remember to move the belt
downto remove stylus.
Black carbon dustiscreated
during the recording process. Use
asoft, oil-free rag tocleanthe
viewing doorand metal platen be-
hindthe paperLow pressure
compressed airmaybe used to
blow dustoutofthe caseand
away from moving parts iftheair
isdryand freeofoil.
Aftereveryfive rollsof paper;
the stylus beltand thewheels it
rides on should bewiped clean
with asoft rag moistenedwithal-
coholtoremove carbon dust.
Strong solvents orabrasive clean-
ersshouldnotbeused.
All mechanicalqonnections
should bechecked periodicallyto
besure theyhaven'tworked loose.
DO NOT apply anytypeof lu-
bricantto the motorsorgeartrains.
DO NOTwash the unitwith
running water.Wiping itwith a
dampclothtoremove salt ac-
cumulations,dust, or road grime is
all that's necessary.
HIGH VOLTAGE ispresent in
thetransmitter sectionwhenthe
unitisON. No attempt should be
made by anyunauthorized person
tomodify or repairthe electronic
section.
Corrosion mayoccuratthe
power plug, in thefuse holderor
power cord splices,or atthe bat-
tery connections.Allelectrical
connections should be checked
periodically and cleaned as
necessary.
Thefaceofthetransducer;if
10'-120' 1 Fastest paper
speed
130'-510' 2 Medium fast
paperspeed
520-830' 3 Medium slow
paperspeed
Below 840' 4 Slowest paper
speed
Thechartpapermaybeslowed
(A
T
- —
Figure 40
igure 10 SUPPRESSION: TOOHIGH
UP.
6 15
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CAUTION — High voltageis
presentintheelectronic section
when the unitis turned on.
1. TURN THE UNIT OFF.
2. Release both catches on the
top ofthe case. Pull out and
downonthetopofthe case
fronttoexposethe stylus belt.
(See Figure36.)
3. Thestylus belt rides overtwo
wheels locatedattheright
edge oftheplaten assembly.
Movethe frontofthebelt
DOWN to positionthe stylus
atthe center
ofthe platen.
4. Hold the stylus belt
stationary
with one finger, andremove
the old stylus bystarting atits
leftedge and moving itout
from underthetabson the
stylus holder.
5. Before installingthenew
stylus, be sure it is bent prop-
6. Referto Figure 38to be sure
thenew stylus ispositioned
correctly underthetabson
the holder.Besure itmoves
freelyin the two slots. Ifnot,
bend the stylus away fromthe
edge itis rubbingon until it
doesmove freely.
7. Afterinstalling, ifthestylus
won'tprint allthewaydown
the paper,(See Figure 39)
bend the right legdownso
that more pressure isexerted
against the stainlesssteel
plate. Ifitstill does notprint
alltheway, bend the leftleg
downmore (butnot so far that
it digs intothe paper).
8. Closethefrontofthe case.
Latch both catches
onthetop
ofthecase.
line onthetargetcompletely,
showing no black, which makes
thetargetdifficult tosee.
RANGE
The LowranceX-1550straight
linegraph hasthemost advanced
range selection capability ofany
depth sounder in its price range.
We urgeyoutoread this section
carefully togetthemostoutof
your
X-1550.
Lower Limit
When youfirstturnontheX-
1550,the range willbe 0-60feet.
Figure 13
S -S
12 2
SM 24
Asyoutravel, thebottom may
descend below 60feet. To
change toadeeper range, simply
press thedesired depth onthe
Keyboard, and then press
LOWER LIMIT.
Example: Display 0-80feet.
bIJ L I
Figure 12 GRAYLINE : ON"
Press: 8 0 LOWER LIMIT
Thedepth willthen be displayed:
Figure14
U S
—EO—---—--L
Any depth in amultiple often
(i.e. 10, 20, 30, 150, 320, etc.)
may be used as a lowerlimit at
the bottom ofthe chartpaper.
Example: Display 0-190
Press: 1 9 0
Result:Figure 15
— S
STYLUS REPLACEMENT erlybycomparing itto Figure 37.
fl:,'
- 12
A-
Figure 11 GRAYLINE OFF'
Figure37
lb lb
—32 22
—40 49
—bH
I 'qI' ''"'r.-
______ II. Iiri
Sb 36
40 40
feet.
LOWER
LIMIT
—20 30
— lb lb —
— 114 li-I —
—. 52 lS2 —
IRS 0 0 — IRS
14 7
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Ifyouwishtodisplay yourdepth
settings at any
time,simplypress
LOWER LIMITor UPPER LIMIT
Your range will immediately be
printed on thepaper. Thiswill not
change thedepth setting.
LINES
WhentheX-1550 isfirstturned
on, depth lineswillbeprinted
on
thepaper. Ifyoudesiretoturn
theLines off, press the LINES
key.ToturntheLinesbackon,
20 - press the Lines key again.
Marker
Amarkerisincluded in the
X-1550 so thatevents
maybe
setting
Figure 17
-
'-ID
-
H'-I
-ID -
-
'-lB
—
-92
Note thatthe paperspeed slows
downautomatically atthis range
Clear-Toclear an entrybefore
hitting theLOWER key, press 0
fourtimes.Thedesired numbers
may then be re-entered.
UPPERLIMIT
Many timeswhen youare fish-
ing,itisdesirable to"blowup"or
expand asection ofthewaterbe-
neath you.Thisis made possible
by theX-1550 toshowsegments
oftheunderwater worldon the
graphpaper. By using theUP-
PER LIMITkey,any depth in mul-
tiplesof 10 maybedisplayed at
theTOP ofthechartpaper.
Example: Display 20-60feet.
Press: 2 0 UPPER
LIMIT
Result:Figure 16
Lie —
92 —
Lb -
—bD U U —bO -
Figure31 Figure34
•20
-96
-
LILt
-52
Example:
Press: Lines
- Result: Figure 18 a
52 - 2
-60 U - U—ba- 24
Notice: No surface signal will be
displayed. 96 96
Example: Display 40to 60feet.
Press: 4 0 UPPER
LIMIT 48 48
Result:Figure 17
Theseranges can be used in 60 U 60
various combinations to show
segments fromthe surface tothe
bottom. See representative sam- Figure33
pIesofsegments on page23. 8 13
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used in this unit.
(Hint:
small strips
oftape maybestored
inside housing.)
9. Hold the take-up spool, and
turnthe supply spool clock-
wiseto puta small amount of
tension on the paper. Itshould
besnugagainst the platen.
(SeeFigure 33.)
10. Pushthe platen assembly
backtoitsoperating position.
Be sure itengages thecatch
inside the top ofthecase.
(SeeFigure 34.)
11. Closethefrontofthecase.
Latchboth catches onthetop
ofthecase.(See Figure35.)
12. Turn the uniton. Movethe
ChartSpeed knob fully
clockwise. Watch thepaper
longenough to be sure itis
moving smoothly and evenly
acrossthe platen. Ifthe paper
flutters orbegins to run up-
hill', repeat Step 8.
marked whendesired. Tousethe
marker,simply press theMARK/
SCC keyand averticalline will
bedisplayed across theentire
page. Hold theMARK/SCC key
downandtheunitwill print the
verticalline foras longasthekey
ishelddown.
Press: MARK
Result: Figure 19
Scale
Thenumbers thatindicate the
depth orscale maybedeleted if
desired.Pressingthe SCALE key
oncewill stop theprinting ofthe
scale numbers. Thescale maybe
displayed again by pressing the
SCALE key.
Remember,thescale may be
displayed atanytime bypressing
eithertheLOWER LIMIT or the
UPPER LIMITkey.
Example:
Press: SCALE
Result: Figure 20
End-of-Paper
Marker
Thegraph paperusedinthe
X-1550 hasared line printedat
the bottom ofthepapertosignify
whenthereisonly 2to3feet be-
foretheendofthe paper.
_________
Figure 21
ZeroAdjustment
YourX-1550 is equipped with
anelectronic zeroadjustment.
Thisallows
youtocenterthe
printing whenitshiftsdue-tosty-
lus wearorchart paperalign-
ment. To adjust the electronic
zero, insert a /o slotted screw-
driver intothepotentiometer slot
and rotateitclockwise for upward
movement and counterclockwise
fordownward movement. Adjust
until thetopandbottomlines are
thesamedistance fromthe edge
ofthepaper.
Caution: Do notforce orjam
screwdriver intothe potentiometer
slotas thiscould cause
damage
toyourunit.
Figure 22
Example: 2
-o
2H
bO
Figure30
12 U
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IVHOW TOREADGRAPHS
"Arched Signatures"
Aremarkable advantage ofthe
X-1550isthat itcan record indi-
vidualfish with a characteristic
arched mark thatseparates them
fromtheirstationary surroundings.
Thereason for this is shown be-
low. Thedistance to afishwhenit
moves intothesonar'sconeof
sound is shown as "A" inFigure22.
When thefish has moved
tothecenterofthecone, thedis-
tance to itwill be shorter, (line
"B"), and as itmovesoutofthe
cone, thedistance will increase
again as shown in line"C".
Ifa partial arch occurs most of
thetimeon yourunit(themark
curves
up but does notcurve back
down), it isbecause thetrans-
ducer is not aimed straight down.
Sharp, well-defined signatures
will occurmostoften whenthe
Sensitivity knobis setatthe¾
point
orhigher. (See(A), Figure
23). Remember,too, that there
mustbesomemovement between
the fish and boat todevelop the
arched mark.
Thermoclines
Thetemperature ofwaterin the
lake is seldom constant fromtop
to bottom. Layers ofdifferent
temperatures form,and thejunc-
tionofawarmandcool layerof
wateris called athermocline. The
depthand thickness ofthether-
mocline canvarywiththeseason
ortimeofday.In deep lakes there
may betwoormore, atdifferent
depths. Thermoclines are impor-
tant tothe fisherman because they
are areas which fish are active.
Many timesbaitfishwill beabove
thethermocline whilelargergame
fish suspend justbelow it. (See
(B), Figure23.)
YourLowrance Model X-1550
candetect this invisible layerin
thewater, buttheSensitivity
knob
willprobably haveto beset atthe
¾ point, or higher
V PAPER LOADING
CAUTION
— High voltageis
presentin theelectronic
section
when theunitisturned on.
1. TURN THE UNIT OFF.
2. Release both catcheson the
top ofthe case. Pull out and
downonthetop ofthecase
frontto expose the platen as-
sembly. (See Figure 25.)
3. Move thestylusbeltDOWN,
(on the right sideoftheview-
ingarea), to position the
marking stylus on theback
side oftheplaten. NEVER
move the beltup— thestylus
maybedamaged. (see Figure
26)
SPECIALNOTE:
Thestylus
maybe damaged ifthe platen as-
semblyis pulled downunless the
stylushasbeen moved tothe
backside ofthe platen.
4. Pull out and down onthetab
atthe top, centerofthe platen
assembly toexpose
thepaper
spools. (SeeFigure 27.)
5. To remove the full take-uproll,
pushin and rotate the left
paperretainer knobuntil it
snaps out. (SeeFigure 28.)
Theroll can now be easily
removed fromthe paperspool
end caps.(SeeFigure 29.)
6. Remove theemptysupply
corefromthe rightside in the
same manner.
7. Putafresh rollofpaperin
position on thecentering
posts
ofthe paperspool end
capsonthe supply side (right)
ofthe platen assembly.The
paper must spool offthebot-
tom oftherolL (SeeFigure31.)
8. Drawtheend ofthepaper
across thefacepfthe platen,
around the metering roller,
and tape itsquarely tothe
take-up core. (SeeFigure
32.)Rollseveral inches of
thepaperaround thecore
before installing thetake-up
coreintothetransport.
Align
thetwonotches in thecore
withthetabsonthe lower
take-up spool. (SeeFigure
30.)Push thepaperretainer
knobinandrotateituntil it
locks intoplace.
NOTE: Both LPG-604 and
LPG605chartpapercanbe
Figure 23
10 11
Figure27
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