Page 1
MX-K3
1-2
Safety Precautions
1. This design of this product contains special hardware and many circuits and components specially
for safety purposes. For continued protection, no changes should be made to the original design
unless authorized in writing by the manufacturer. Replacement parts must be identical to those
used in the original circuits. Services should be performed by qualified personnel only.
2. Alterations of the design or circuitry of the product should not be made. Any design alterations of
the product should not be made. Any design alterations or additions will void the manufacturer`s
warranty and will further relieve the manufacture of responsibility for personal injury or property
damage resulting therefrom.
3. Many electrical and mechanical parts in the products have special safety-related characteristics.
These characteristics are often not evident from visual inspection nor can the protection afforded
by them necessarily be obtained by using replacement components rated for higher voltage,
wattage, etc. Replacement parts which have these special safety characteristics are identified in
the Parts List of Service Manual. Electrical components having such features are identified by
shading on the schematics and by ( ) on the Parts List in the Service Manual. The use of a
substitute replacement which does not have the same safety characteristics as the recommended
replacement parts shown in the Parts List of Service Manual may create shock, fire, or other
hazards.
4. The leads in the products are routed and dressed with ties, clamps, tubings, barriers and the
like to be separated from live parts, high temperature parts, moving parts and/or sharp edges
for the prevention of electric shock and fire hazard. When service is required, the original lead
routing and dress should be observed, and it should be confirmed that they have been returned
to normal, after re-assembling.
5. Leakage currnet check (Electrical shock hazard testing)
After re-assembling the product, always perform an isolation check on the exposed metal parts
of the product (antenna terminals, knobs, metal cabinet, screw heads, headphone jack, control
shafts, etc.) to be sure the product is safe to operate without danger of electrical shock.
Do not use a line isolation transformer during this check.
Plug the AC line cord directly into the AC outlet. Using a "Leakage Current Tester", measure
the leakage current from each exposed metal parts of the cabinet , particularly any exposed
metal part having a return path to the chassis, to a known good earth ground. Any leakage
current must not exceed 0.5mA AC (r.m.s.)
Alternate check method
Plug the AC line cord directly into the AC outlet. Use an AC voltmeter having, 1,000 ohms
per volt or more sensitivity in the following manner. Connect a 1,500 10W resistor paralleled by
a 0.15 F AC-type capacitor between an exposed
metal part and a known good earth ground.
Measure the AC voltage across the resistor with the
AC voltmeter.
Move the resistor connection to eachexposed metal
part, particularly any exposed metal part having a
return path to the chassis, and meausre the AC
voltage across the resistor. Now, reverse the plug in
the AC outlet and repeat each measurement. voltage
measured Any must not exceed 0.75 V AC (r.m.s.).
This corresponds to 0.5 mA AC (r.m.s.).
Warning
1. This equipment has been designed and manufactured to meet international safety standards.
2. It is the legal responsibility of the repairer to ensure that these safety standards are maintained.
3. Repairs must be made in accordance with the relevant safety standards.
4. It is essential that safety critical components are replaced by approved parts.
5. If mains voltage selector is provided, check setting for local voltage.
Good earth groundPlace this
probe on
each exposed
metal part. AC VOLTMETER
(Having 1000
ohms/volts,
or more sensitivity)
1500 10W
0.15 F AC TYPE
!
CAUTION Burrs formed during molding may be left over on some parts of the chassis. Therefore,
pay attention to such burrs in the case of preforming repair of this system.
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MX-K3
1-3
Important for laser products
1.CLASS 1 LASER PRODUCT
2.DANGER : Invisible laser radiation when open and inter
lock failed or defeated. Avoid direct exposure to beam.
3.CAUTION : There are no serviceable parts inside the
Laser Unit. Do not disassemble the Laser Unit. Replace
the complete Laser Unit if it malfunctions.
4.CAUTION : The compact disc player uses invisible
laserradiation and is equipped with safety switches
whichprevent emission of radiation when the drawer is
open and the safety interlocks have failed or are de
feated. It is dangerous to defeat the safety switches.5.CAUTION : If safety switches malfunction, the laser is able
to function.
6.CAUTION : Use of controls, adjustments or performance of
procedures other than those specified herein may result in
hazardous radiation exposure.
VARNING : Osynlig laserstrålning är denna del är öppnad
och spårren är urkopplad. Betrakta ej strålen.
VARO : Avattaessa ja suojalukitus ohitettaessa olet
alttiina näkymättömälle lasersäteilylle.Älä katso
säteeseen.ADVARSEL : Usynlig laserstråling ved åbning , når
sikkerhedsafbrydere er ude af funktion. Undgå
udsættelse for stråling.
ADVARSEL : Usynlig laserstråling ved åpning,når
sikkerhetsbryteren er avslott. unngå utsettelse
for stråling.
REPRODUCTION AND POSITION OF LABELS
WARNING LABEL
DANGER : Invisibie laser radiation
when open and interlock or
defeated.
AVOID DIRECT EXPOSURE TO
BEAM (e) VARNING : Osynlig laserstrålning är
denna del är öppnad och spårren är
urkopplad. Betrakta ej strålen. (s) VARO : Avattaessa ja suojalukitus
ohitettaessa olet alttiina
näkymättömälle lasersäteilylle.Älä
katso säteeseen. (d) ADVARSEL :Usynlig laserstråling
ved åbning , når
sikkerhedsafbrydere er ude af
funktion. Undgå udsættelse for
stråling. (f)
! CAUTION Please use enough caution not to
see the beam directly or touch it
in case of an adjustment or operation
check.
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MX-K3
1-12
Fig.18 Prior to performing the following procedures,
remove the top cover.
Also remove the CD changer unit.
Also remove the CD changer mechanism
1.
2.Widen the section "f ".
While keeping the section "f" wide open, push the
section "g" in the direction of the arrow to remove
the shaft, and then remove the CD pickup.
Removing the CD pickup (See Fig.18)
Fig.19
Fig.20 Fig.21
Prior to performing the following procedure,
remove the top cover.
1.
2.
3.Pull out the CD tray.
Remove the belt from the pulley.
Remove the two screws "L" retaining the CD
changer tray loading motor.
Replacing the loading motor and belt
of the CD changer tray (See Fig.19)
Prior to performing the following procedures,
remove the top cover.
Also remove the CD changer unit.
1.
2.
3.
4.
5.
6.Remove the two screws "M" retaining the stopper
brackets on both sides of the CD changer unit.
Remove the stopper brackets from both sides of
the CD changer unit.
Pull out the CD tray from the CD changer unit, all
the way and then lift the tray upward to remove.
Turn the CD tray upside down and remove the tray
rotor belt from the pulley.
Turn the CD tray upside down and disconnect the
card wire from the connector CN605 on the CD
tray rotor motor assembly.
Remove the two screws N retaining the CD tray
rotor motor, and then remove the CD tray rotor
motor.
Replacing the CD tray rotor belt of the
CD changer, and removing the motor
(See Fig.20 and 21) L
Pulley
Belt
CD tray
M Stopper bracket
N Pulley
CN605CD tray
rotor belt
g f
CD pickup
Shaft
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MX-K3
1-20
Flow of functional operation until TOC read
Slider turns REST
SW ON.
Automatic tuning
of TE offset
Laser ON
Detection of disc
Automatic measurement of
Focus S-curve amplitudeAutomatic tuning of
Focus offset
Disc is rotated
Focus servo ON
(Tracking servo ON)
Automatic tuning of
Tracking error balance Automatic measurement of
Tracking error amplitude
Automatic tuning of
Focus error balance
Disc to be
braked to stop Tracking
servo
on states Tracking
servo
off states
Disc states
to rotateTOC reading
finishes Automatic measurement
of TE amplitude and
automatic tuning of
TE balance500mv/div
2ms/div
Fig.1
Approx.3sec
pin 20 of
IC611(TE)
Approx
1.8V
VREF
Tracking error waveform at TOC reading
Power ONPlay Key
Confirm that the Focus error
S-cuve signal at the pin32 of
IC601 is approx.2Vp-p
Confirm that the signal from
pin24 IC601 is 0V as a
accelerated pulse during
approx.400ms.
Confirm the waveform of
the Tracking error signal.
at the pin 20 of IC611 (R643)
(See fig-1)
Automatic tuning of
Focus error gain
Automatic tuning of
Tracking error gain
TOC reading
Play a disc
Confirm the eys-pattern
at the lead of TP3
Confirm that the voltage at the pin5
of CN602 is "H"\"L"\"H".Check Point
Check that the voltage at the
pin40 of IC601 is + 5V?