JVC MX-K1 User manual

SERVICE MANUAL
COMPACT COMPONENT SYSTEM
No.20942
May. 2001
COPYRIGHT 2001 VICTOR COMPANY OF JAPAN, LTD.
MX-K1
MX-K1
Contents
Safety precautions
Important for laser products
Preventing static electricity
Disassembly method
Adjustment method
Flow of functional
operation until TOC read
Maintenance of laser pickup
Replacement of laser pickup
Description of major ICs
1-2
1-3
1-4
1-5
1-18
1-20
1-21
1-21
1-22
Area Suffix
J
C
U.S.A.
Canada
ACTIVE
BASS EX.
COMPACTCOMPONENT SYSTEM MX-K1
STANDBY/ON
STANDBY
PHONES
REPEAT PROGRAM RANDOM /STOP REC START DUBBING
REC START
CD
CLOCK
/TIMER
TAPE
A/B
DISC SKIP
EJECT
PLAY
A
REC/PLAY
B
CD CONTROL
CD
1
AUX
FM/AM
CD
TAPE
CD
2
CD
3
CD-R/RW PLAYBACK
VCDNUMBERRETURNPBC
MAXMIN
MIC MIC
VOL
CANCEL SET
1 BIT DUALD/A
CONVERTER
PRESET
TUNNIG
/ DEMO
COMPU PLAYCONTROL
ACTIVE BASS EXTENSION
FULL - LOGIC CONTROL CD SYNCHRO RECORDING
EJECT
R
O
C
K
C
L
A
S
S
I
C
P
O
P
V
O
L
U
M
E
3-CD
PLAY& EXCHANGE
SOUND
MODE
RM-SMXK3A REMOTE CONTROL
1 2 3
456
789
10 +10 FM MODE
FM /AM
AUX
SLEEP
STANDBY/ON
CD 1 CD 2 CD 3 CD
SOUND
MODE
ACTIVE
BASS EX.
FADE
MUTING
VOLUME
1
1
PROGRAM
/RANDOM REPEAT TAPE A/B
TAPE
11
111
1
1
1
COMPU PLAY
CONTROL
CA-MXK1SP-MXK1 SP-MXK1

MX-K1
1-2
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.).
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 ground
Place this
probe on
each exposed
metal part.
AC VOLTMETER
(Having 1000
ohms/volts,
or more sensitivity)
1500 10W
0.15 F AC TYPE
!
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.
In regard with component parts appearing on the silk-screen printed side (parts side) of the PWB diagrams, the
parts that are printed over with black such as the resistor ( ), diode ( ) and ICP ( ) or identified by the " "
mark nearby are critical for safety.
When replacing them, be sure to use the parts of the same type and rating as specified by the manufacturer.
(Except the J and C version)

MX-K1
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.

MX-K1
1-4
Preventing static electricity
1. Grounding to prevent damage by static electricity
Electrostatic discharge (ESD), which occurs when static electricity stored in the body, fabric, etc. is discharged,
can destroy the laser diode in the traverse unit (optical pickup). Take care to prevent this when performing repairs.
2. About the earth processing for the destruction prevention by static electricity
In the equipment which uses optical pick-up (laser diode), optical pick-up is destroyed by the static electricity of
the work environment.
Be careful to use proper grounding in the area where repairs are being performed.
2-1 Ground the workbench
Ground the workbench by laying conductive material (such as a conductive sheet) or an iron plate over
it before placing the traverse unit (optical pickup) on it.
2-2 Ground yourself
Use an anti-static wrist strap to release any static electricity built up in your body.
3. Handling the optical pickup
1. In order to maintain quality during transport and before installation, both sides of the laser diode on the
replacement optical pickup are shorted. After replacement, return the shorted parts to their original condition.
(Refer to the text.)
2. Do not use a tester to check the condition of the laser diode in the optical pickup. The tester's internal power
source can easily destroy the laser diode.
4. Handling the CD changer unit (optical pickup)
1. Do not subject the CD changer unit (optical pickup) to strong shocks, as it is a sensitive, complex unit.
2. Cut off the shorted part of the flexible cable using nippers, etc. after replacing the optical pickup. For specific
details, refer to the replacement procedure in the text. Remove the anti-static pin when replacing the CD changer
unit. Be careful not to take too long a time when attaching it to the connector.
3. Handle the flexible cable carefully as it may break when subjected to strong force.
4. It is not possible to adjust the semi-fixed resistor that adjusts the laser power.
Do not turn it
Conductive material
(conductive sheet) or iron plate
(caption)
Anti-static wrist strap
Attention when traverse unit is decomposed
1. Remove the CD changer unit.
2. Disconnect the harness from connector on the CD motor board.
3. Solder is put up before the card wire is removed from connector CN601
on the main board as shown in Fig.1 and Fig. 2.
(When the wire is removed without putting up solder, the CD pick-up
assembly might destroy.)
4. Please remove solder after connecting the card wire with CN601 when
you install picking up in the substrate.
*Please refer to "Disassembly method" in the text for pick-up and how to
detach the CD changer mechanism.
Soldering
Fig.2
Flexible cable
Fig.1
CD changer
mechanism
assembly
CD changer
unit

MX-K1
1-5
Disassembly method
Top cover
CD changer unit
Front panel assembly
Chassis unit
CD changer unit
Removing the main PCB
Removing the CD changer mechanism assembly
Removing the CD pickup
Replacing the loading motor and belt of the CD changer tray
Replacing the CD tray rotor belt of CD changer, and removing the motor
Front panel assembly
Removing the cassette deck mechanism
Removing the earphone jack PCB
Removing the control/FL PCB
Removing the switch PCB and ACTIVE BASS EX. switch PCB
Removing the cassette deck main motor, and replacing the main belts
Removing the leaf switches of the cassette deck mechanism
Removing the cassette deck heads
Chassis unit
Removing the 3-pin regulator
Removing the power amp and supply PCB and the Power Trans PCB
Commence disassembly of this set by removing the main units and then proceed to the components and
assemblies inside the units.
Replacement of the fuses and the power IC

MX-K1
1-6
Fig.1
[Caution] Be sure to use fuses with the specified
ratings.
Replacing the fuses (See Fig.1)
1.
Prior to performing the following procedure, remove
the top cover.
Replace the fuses inside.
1.
2.
Prior to performing the following procedure, remove
the top cover.
Also remove the rear panel. (See Fig.33)
Remove the screw "A" from the bracket that retains
the power IC.
Remove the solder fixing the power IC.
Replacing the power IC
(See Fig.2 and 3)
Fig.3
Fig.2
<Disassembly of the main blocks of this set>
Replacement of the fuses and the power IC
A
Heat sink
Power amp
and supply PCB
Fuse (F951)
1A 250V
Power trans PCB
Fuse (F952)
1.6A 250V
Chassis
Power amp and supply PCB
Power IC
soldering part
Heat sink

MX-K1
1-7
Fig.4
Removing the top cover
(See Fig.4 and 5)
1.
2.
3.
Remove the six screws "B" that retain the top cover
from the rear of the body.
Remove the four screws "C" that retain the top
cover from the two sides of the body.
Remove the top cover from the body by lifting it
toward the rear.
Fig.5
B
BB
Top cover
Front panel assembly
C

MX-K1
1-8
Fig.6
[Caution] Although the CD mechanism unit can be
removed without removing the CD tray
panel, it is still recommended to remove it
in order to prevent damage.
Prior to performing the following procedures,
remove the top cover.
a.
b.
c.
1.
2.
3.
4.
5.
From the front panel side of this set, push in the
sections marked with arrows and pull out the CD
tray toward the front.
Remove the CD tray panel by pushing both of its
extremities upward in the direction of the arrows.
Push the CD tray deep into the set.
Disconnect the cassette head wires from the
connectors CN307 and CN308 on the main PCB,
which is located below the CD changer unit.
Disconnect the card wires from the connectors
CN301, CN302 and CN305 on the main PCB.
Disconnect the parallel wires from the connectors
CN902A, CN902B and CN902C on the power amp
and supply PCB.
From the rear of the set, remove the two screws
"D" retaining the CD changer unit, then remove the
three screws "E" and the screw "F" retaining the
ANTENNA terminal and the AUX IN terminal.
Push down and disengage the two claws "a"
holding the CD changer unit at the bottom of its
front panel and then remove the CD changer unit
(Fig. 9).
Removing the CD changer unit
(See Fig.6 to 9)
Fig.8
Fig.9
Fig.7
CD tray panel
CD tray panel
D
F
E
AUX IN
terminal
ANTENNA
terminal CD changer
unit
Claw a

MX-K1
1-9
Fig.10
Prior to performing the following procedures,
remove the top cover.
Also remove the CD changer unit.
1.
2.
3.
4.
5.
Disconnect the parallel wire and card wire from the
connectors CN101 and CN901 on the power amp
and supply PCB.
Remove the two screws "G" retaining the front
panel assembly onto the bottom of the body.
Remove the screw "H" retaining the cassette deck
mechanism and then remove the GND lug "b" that
comes from the power amp and supply PCB.
Remove the solder connecting the wire on the
control/FL PCB.
Disengage the claws "c" on both sides at the
bottom of the front panel assembly and then
remove the assembly.
Removing the front panel assembly
(See Fig.10 and 11)
Fig.11
G
H
Power amp and
supply PCB
Control/FL PCB
Claw c
GND lug b

MX-K1
1-10
Fig.12
Prior to performing the following procedures,
remove the top cover.
Also remove the CD changer unit.
1.
2.
3.
4.
5.
6.
Disconnect the wires from CN602 and CN603 on
the main PCB, which is located on the backside of
the CD changer unit.
Disconnect the card wire from connector CN604 of
the main PCB at the back of the CD changer unit.
The three screws "I" and the screw with the washer
"J" that retain the main PCB should be removed.
Remove the main PCB by pulling it toward the side
where the CN601 is located.
Using solder, short the CD pickup to connect to
short round.
Disconnect the card wire from the connector
CN601 on the main PCB and then remove the
main PCB.
Removing the main PCB
(See Fig.12 and 13)
Fig.13
<Disassembly of units and assembly
inside this set>
[Caution] After re-connecting the wires, be sure to
remove the shorting solder from the GND
connection.
Main PCB
CN601
CN603CN602
CN604
II
J
Main PCB
Short round
CN601

MX-K1
1-11
Fig.14
Prior to performing the following procedures,
remove the top cover.
Also remove the CD changer unit.
1.
2.
3.
Remove the spring "d" from the front surface of the
CD changer mechanism unit.
Turn the CD changer mechanism unit upside down,
and remove the spring "e" connecting the unit to
the CD changer mechanism assembly.
Remove the two screws "K" retaining the CD
changer mechanism assembly.
Removing the CD changer mechanism
assembly (See Fig.14 to 16)
Fig.16
Fig.15
[Caution] When replacing the CD changer
mechanism assembly, be sure not to
mistake the positions of the red and blue
dampers.
[Note] When re-assembling after the disassembly
work, apply bonding agent on the spring to
prevent it from slipping off.
Spring d
CD changer
unit
CD changer
mechanism
assembly
Spring e
K
Red Red
CD changer
mechanism
assembly
BlueBlue
[Note]
[Note]

MX-K1
1-12
Fig.17
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.17)
Fig.18
Fig.19 Fig.20
Prior to performing the following procedure,
remove the top cover.
1.
2.
3.
Pull out the CD changer 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.18)
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.19 and 20)
L
Pulley
Belt
M
Stopper bracket
N
Pulley
CN605
CD tray
rotor belt
[Caution] When pushing in the CD changer tray, be
sure to lower the CD changer mechanism
assembly by manually turning the UD
cam gear in the direction of the arrow.
gf
CD pickup
Shaft
UD cam gear
CD changer
tray

MX-K1
1-13
Prior to performing the following procedure, remove
the top cover.
Also remove the CD changer unit.
Also remove the front panel assembly.
1.Remove the five screws "O" retaining the cassette
deck mechanism from the back of the front panel
assembly.
Removing the cassette deck mechanism
(See Fig.21)
Prior to performing the following procedure, remove
the top cover
Also remove the CD changer unit.
Also remove the front panel assembly.
1.Remove the screw with the washer, "P" that retains
the earphone jack PCB from the back of the front
panel assembly.
Removing the earphone jack PCB
(See Fig.22)
Prior to performing the following procedure, remove
the top cover.
Also remove the CD changer unit.
1.Remove the three screws "Q" that retain the
control/FL PCB from the back of the front panel
assembly.
Removing the control/FL PCB
(See Fig.23)
O
O
Front panel
assembly
Fig.21
P
Front panel
assembly
Earphone jack
PCB
Fig.22
Q
Front panel
assembly
Control/FL
PCB
Fig.23

MX-K1
1-14
Fig.24
Prior to performing the following procedures,
remove the top cover.
Also remove the CD changer unit.
Also remove the front panel assembly.
1.
2.
3.
4.
5.
6.
Pull out the volume control knob from the front of
the front panel assembly.
Remove the nut and washer retaining the volume
knob shaft.
Remove the three screws "Q" retaining the
control/FL PCB from the back of the front panel
assembly.
Remove the control/FL PCB.
Remove the eleven screws "R" retaining the switch
PCB.
Remove the two screws "S" retaining the ACTIVE
BASS EX. switch PCB.
Removing the switch PCB and ACTIVE
BASS EX. switch PCB (See Fig.23 to 26)
Fig.25
Fig.26
R
R
SACTIVE BASS EX. switch PCB
Switch
PCB
Volume knob
Front panel assembly
Front panel
assembly
Nut
Volume shaft
Washer

MX-K1
1-15
Fig.27
Fig.28
Prior to performing the following procedures,
remove the top cover.
Also remove the CD changer unit.
Also remove the front panel assembly.
1.
2.
3.
4.
Remove the five screws "O" retaining the cassette
deck mechanism.
Remove the cassette deck mechanism.
Remove the two screws "T" retaining the main
motor from the front side of the cassette deck.
From the backside of the cassette deck, remove
the main motor and two main belts.
Removing the cassette deck main
motor, and replacing the main belts
(See Fig.21, 27 and 28)
Fig.29
[Caution]
[Caution]
After attaching the main motor, check the
orientation of the motor and the polarity of
the wires.
The lengths of the cassette A (playback
only) and cassette B (record/play) main
belts are different. When attaching the
main belts, use the longer belt for
cassette A.
Prior to performing the following procedures,
remove the top cover.
Also remove the CD changer unit.
Also remove the front panel assembly.
1.
2.
3.
4.
5.
Remove the five screws "O" that retain the cassette
deck mechanism.
Remove the cassette deck mechanism.
Turn the cassette deck mechanism upside down.
Remove the solder from around the leaf switches.
Pull out the leaf switches from the front side of the
cassette deck mechanism.
Removing the leaf switches of the
cassette deck mechanism
(See Fig.21 and 29)
Cassette deck mechanism
(Back side)
Solder side of leaf switch
T
Cassette deck mechanism
(Front side)
Cassette deck mechanism
(Back side) Cassette deck main motor
Main belt
(For A cassette)
Main belt
(For B cassette)

MX-K1
1-16
Fig.30
Prior to performing the following procedures,
remove the top cover.
Also remove the CD changer unit.
Also remove the front panel assembly.
1.
2.
3.
4.
5.
6.
Remove the five screws "O" that retain the cassette
deck mechanism.
Remove the cassette deck mechanism and place it
so that the front side faces up.
Remove the solder from the bottom side of the
head terminal and disconnect the wire.
Remove the screw "U" that retains the head.
Loosen the screw "V" that retains the head.
Hold the head and slide it in the direction of the
arrow to remove it.
Removing the cassette deck heads
(See Fig.21 and 30)
Fig.31
Fig.32
Prior to performing the following procedures,
remove the top cover.
Also remove the rear panel. (See Fig.33)
1.
2.
Remove the screw "W" that retains the bracket
holding the 3-pin terminal regulator.
Remove the solder fixing the 3-pin regulator.
Removing the 3-pin regulator
(See Fig.31 and 32)
Cassette deck mechanism
(Front side)
VU
PB Head REC/PB Head
VU
W
Heat sink
Power amp
and supply PCB
Power amp and supply PCB
Solder on the
3-pin regulator
Heat sink

MX-K1
1-17
Fig.34
Prior to performing the following procedures,
remove the top cover.
Also remove the CD changer unit.
1.
2.
3.
4.
5.
6.
7.
8.
Remove the two screws "X" that retain the
SPEAKERS terminals.
Remove the screw "Y" that retains the rear panel,
and then remove the rear panel.
Disconnect the parallel wires from the connectors
CN901A and CN901B on the power amp and
supply PCB.
Disconnect the parallel wire and card wire from
the connectors CN101 and CN901 on the power
amp and supply PCB.
Remove the three screws "Z" retaining the heat
sink onto the bottom of the chassis.
Remove the screw "AA" that retain the power amp
and supply PCB and then remove the assembly.
Remove the clamp of AC power cord from the
chassis.
Remove the four screws "AB" that retain the
power trans PCB and then remove the assembly.
Removing the power amp and supply
PCB and the power trans PCB
(See Fig.33 to 37)
Fig.36
Fig.35
(Top view)
Fig.37
Fig.33
Rear panel
Speaker
terminal
Y
X
Chassis
Chassis
AA
Power amp and
supply PCB
Heat sink
Rear
Z
Chassis
Power amp and
supply PCB
CN901B
CN901A
AB
Chassis
Power trans PCB
Clamp AC power cord
AB

MX-K1
1-18
Adjustment method
Measurement instruments required
for adjustment
1. Low frequency oscillator,
This oscillator should have a capacity to output 0dB
to 600ohm at an oscillation frequency of 50Hz-20kHz.
2. Attenuator impedance : 600ohm
3. Electronic voltmeter
4. Frequency counter
5. Wow flutter meter
6. Test tape
VT712 : For Tape speed and wow flutter ( 3kHz)
VT703 : For Head angle(10kHz),Play back frequency
characteristics(1kHz),and dubbing frequency
characteristics(63,1,10kHz)
7. Blank tape
TAPE : AC-225, TAPE : AC-514
8. Torque gauge : For play and back tension
Forward ; TW2111A, Reverse ; TW2121A
Fast Forward and Rewind ; TW2231A
9. Test disc
: CTS-1000(12cm),GRG-1211(8cm)
10. Jitter meter
Measurement conditions
Power supply voltage
AC120V (60Hz)
Measurement
output terminal : Speaker out
: TP101(Measuring for TUNER/DECK/CD)
: Dummy load 6ohm
Radio input signal
AM modulation frequency : 400Hz
Modulation factor : 30%
FM modulation frequency : 400Hz
Frequency displacement : 22.5kHz
Frequency Range
AM 531kHz~1710kHz
FM 87.5MHz~108MHz
Standard measurement positions of volume
and switch
Power : Standby (Light STANDBY Indicator)
S,A,BASS : OFF
Sound mode : OFF
Main VOL. : 0 Minimum
Travers mecha set position : Disc 1
Mic MIX VOL : MAX
ECHO : OFF
Precautions for measurement
1. Apply 30pF and 33kohm to the IF sweeper output
side and 0.082 F and 100kohm in series to
the sweeper input side.
2. The IF sweeper output level should be made as
low as possible within the adjustable range.
3. Since the IF sweeper is a fixed device, there is
no need to adjust this sweeper.
4. Since a ceramic oscillator is used, there is no need
to perform any MPX adjustment.
5. Since a fixed coil is used, there is no need to adjust
the FM tracking.
6. The input and output earth systems are separated.
In case of simultaneously measuring the voltage
in both of the input and output systems with an
electronic voltmeter for two channels, therefore,
the earth should be connected particularly.
7. In the case of BTL connection amplifier, the minus
terminal of speaker is not for earthing. Therefore,
be sure not to connect any other earth terminal
to this terminal. This system is of an OTL system.

MX-K1
1-19
Arrangement of adjusting positions
Items Measurement
conditions Measurement method Standard
values Adjusting positions
Tape recorder section
Tuner section
Cassette deck mechanism
(Front side)
Head azimuth screw
(Forward side)
PB Head
(Deck-A)
REC/PB Head
(Deck-B)
T1
L2
Main P.C.B. Ass'y
CN308
L301
8-Pin
Head screw Head screw
Head azimuth screw
(Forward side)
1. Playback the test tape VT703 (10KHz) or equivalent.
2. Adjust the head azimuth screw to obtain maximum
output and both output of L / R is in 3dB.
3. Put on the screw lock paint after alignments.
1. Insert the recording tape in deck-B.
2. Starting the recording.
3. Adjust the oscillation frequency to 80KHz+/-3KHz by
core of Oscillation coil of L301.
Test tape
: VT703 (10kHz)
Measurement output
terminal
: Left and Right
speaker output
(6-ohm loaded)
or
Headphone Output
(32-ohm loaded)
Test tape
: TYPE AC-514
Measurement output
terminal
: Erase head terminal
(CN308 8-Pin)
Maximum output
80kHz+/-3kHz
Head azimuth
screw
Adjust the head
azimuth screw only
when the head has
been changed.
Bias coil: L301
Use the High-
Impedance Probe for
Frequency counter
input.
Cassette Head
Azimuth Alignments
Recording Bias
Frequency Alignment
Items Measurement
conditions Measurement method Standard
values Adjusting positions
OSC coil adjustment
1.Set the Signal Generator signal to 530KHz the feed to
Loop Antenna.
2.Receiving the signal and the adjust the OSC coil (L2)
obtain the V.T is 1.40V +/-0.05V.
Antenna coil check or adjustment
1.Change the receiving frequency to 600KHz.
2.Adjust the Antenna coil ( L2 ) obtain maximum sensitivity.
(Adjust the SSG output to out of AGC range.)
1. Set the receiving frequency to 530KHz.
2. Feed the 450KHz signal to AM IF input.
3.Adjust the IFT Block T1 obtain to maximum output.
(Adjust the SSG output to out of AGC range.)
Input signal
: 530kHz
Measurement point
: Resistor R3 (AM)
Resistor R6 (FM)
Input signal
: 600kHz
Input signal
: 530kHz
V.T
: 1.40V+/-0.05V
Maximum
sensitivity
Maximum output
OSC/Antenna coil
: L2
Adjust the OSC coil
only when the AM coil
block has been
changed.
IFT (T1)
Adjust the IFT only
when the IFT block has
been changed.
AM Tracking
Alignments
AM IFT Alignments
Note: The adjustment of CD section is not required.
FM VT voltage
measurement point
R3
R6
AM VT voltage
measurement point
Antenna coil OSC coil

MX-K1
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 amplitude
Automatic 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 rotate TOC reading
finishes
Automatic measurement
of TE amplitude and
automatic tuning of
TE balance
500mv/div
2ms/div Fig.1
Approx.3sec
pin 20 of
IC611(TE)
Approx
1.8V
VREF
Tracking error waveform at TOC reading
Power ON Play 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?