Sony CMT-A70 - Personal Component System User manual

SERVICE MANUAL
PERSONAL COMPONENT SYSTEM
US Model
Canadian Model
Australian Model
CMT-A70
AEP Model
UK Model
CMT-A50/A70
E Model
CMT-A50
SPECIFICATIONS
CMT-A50/A70
Photo: CMT-A50
Ver. 1.2 2006.02
9-879-211-03
2006B05-1
© 2006.02
Sony Corporation
Personal Audio Division
Published by SonyTechno Create Corporation
US and foreign patents licensed from Dolby Laboratories.
CD player section
System
Compact disc digital audio system
Laser diode properties
Material: GaAlAs
Wave length: 780 nm
Emission duration: Continuous
Laser output: Less than 44.6 µW
(This output is the value measured at a distance of about
200 mm from the objective lens surface on the optical
pick-up block with 7 mm aperture.)
Spindle speed
400 r/min (rpm) to 1 000 r/min (rpm) (CLV)
Number of channels
2
Frequency response
20 - 20 000 Hz +0/–1 dB
Wow and flutter
Below measurable limit
Radio section
Frequency range
FM 87.5 - 108 MHz
AM
US, Canadian models:530 - 1 710 kHz
Other models: 531 - 1 611 kHz (9 kHz step)
530 - 1 610 kHz (10 kHz step)
IF FM: 10.7 MHz
AM: 450 kHz
Aerials
FM: Lead aerial
AM: Loop aerial
Cassette-corder section
Recording system
4-track 2 channel stereo
Fast winding time
Approx. 112 s (sec.) with Sony cassette C-60
Frequency response
TYPE I (normal): 50 - 15 000 Hz
General
Speaker
Tweeter: 4 cm dia., 6 Ω
Woofer: 13 cm dia., 6 Ω
Passive radiator: 10 cm dia. (CMT-A50 only)
InputLINE IN jack (stereo minijack)
Minimum input level 430 mV
Outputs
Headphones jack (stereo minijack):
For 8 - 64 Ωimpedance headphones
OPTICAL DIGITAL OUT (CD) (optical output
connector):
Wavelength: 630 - 690 nm
Maximum power output
CMT-A50: 20 W
CMT-A70: 60 W
Power requirements
For personal component system:
US, Canadian models: 120 V AC, 60 Hz
Korean model: 220 V AC, 60 Hz
Other models: 230 V AC, 50 Hz
For remote control:
3 V DC, 2 R03 (size AAA) batteries
Power consumption
CMT-A50: 50 W
CMT-A70: 100 W
Dimensions
Player:
Approx. 136 ×151.8 ×204 mm (w/h/d)
(incl. projecting parts)
Speaker:
CMT-A50: Approx. 128 ×287 ×215 mm (w/h/d)
(incl. projecting parts)
CMT-A70: Approx. 164 ×267 ×255 mm (w/h/d)
(incl. projecting parts)
Ma CMT-A50:
Player: Approx. 1.6 kg
Left speaker: Approx. 4.3 kg
Right speaker: Approx. 2.2 kg
CMT-A70:
Player: Approx. 1.6 kg
Left speaker: Approx. 5.6 kg
Right speaker: Approx. 2.9 kg
Supplied accessories
Remote control (1)
FM lead aerial (1)
AM loop aerial (1)
CD-ROM (SonicStage) (1)
SonicStage Installation/Operating Guide (1)
Design and specifications are subject to change without
notice.
(US model only)
POWER OUTPUT AND TOTAL HARMONIC
DISTORTION
AUDIO POWER SPECIFICATIONS
With 6 Ωloads, both channels driven from 100 -
10,000 Hz; rated 55 W per channel-minimum
RMS power, with no more than 10 % total
harmonic distortion in AC operation.
Model Name Using Similar Mechanism NEW
CD CD Mechanism Type FLM-A50
Section Optical Pick-up Block Name KSM-213CCP or KSM-213RCP
Optical Pick-up Name KSS-213C or KSS-213R
Tape deck Model Name Using Similar Mechanism NEW
Section Tape Transport Mechanism Type CMAL1Z252A

2
CMT-A50/A70
SAFETY CHECK-OUT
After correcting the original service problem, perform the following
safety check before releasing the set to the customer:
Check the antenna terminals, metal trim,“metallized” knobs, screws,
and all other exposed metal parts forAC leakage.
Check leakage as described below.
LEAKAGE TEST
The AC leakage from any exposed metal part to earth ground and
from all exposed metal parts to any exposed metal part having a
return to chassis, must not exceed 0.5 mA (500 microamperes.).
Leakage current can be measured by any one of three methods.
1. A commercial leakage tester, such as the Simpson 229 or RCA
WT-540A. Follow the manufacturers’instructions to use these
instruments.
2. A battery-operatedAC milliammeter.The Data Precision 245
digital multimeter is suitable for this job.
3. Measuring the voltage drop across a resistor by means of a
VOMor battery-operatedACvoltmeter. The “limit” indication
is 0.75V, so analog meters must have an accurate low-voltage
scale. The Simpson 250 and Sanwa SH-63Trd are examples
of a passive VOM that is suitable. Nearly all battery operated
digital multimeters that have a 2V AC range are suitable. (See
Fig. A)
Notes on chip component replacement
•Never reuse a disconnected chip component.
•Notice that the minus side of a tantalum capacitor may be
damaged by heat.
Flexible Circuit Board Repairing
•Keep the temperature of the soldering iron around 270 ˚C
during repairing.
•Do not touch the soldering iron on the same conductor of the
circuit board (within 3 times).
•Be careful not to apply force on the conductor when soldering
or unsoldering.
CAUTION
Use of controls or adjustments or performance of procedures
otherthan those specifiedhereinmay result inhazardous radiation
exposure.
UNLEADED SOLDER
Boards requiring use of unleaded solder are printed with the lead-
free mark (LF) indicating the solder contains no lead.
(Caution: Some printed circuit boards may not come printed with
the lead free mark due to their particular size)
: LEAD FREE MARK
Unleaded solder has the following characteristics.
•Unleaded solder melts at a temperature about 40 °C higher
than ordinary solder.
Ordinary soldering irons can be used but the iron tip has to be
applied to the solder joint for a slightly longer time.
Soldering irons using a temperature regulator should be set to
about 350 °C.
Caution: The printed pattern (copper foil) may peel away if
the heated tip is applied for too long, so be careful!
•Strong viscosity
Unleaded solder is more viscou-s (sticky, less prone to flow)
than ordinary solder so use caution not to let solder bridges
occur such as on IC pins, etc.
•Usable with ordinary solder
It is best to use only unleaded solder but unleaded solder may
also be added to ordinary solder.
SAFETY-RELATED COMPONENT WARNING!!
COMPONENTS IDENTIFIED BY MARK 0 OR DOTTED LINE
WITH MARK 0ON THE SCHEMATIC DIAGRAMS AND IN
THE PARTS LIST ARE CRITICAL TO SAFE OPERATION.
REPLACE THESE COMPONENTS WITH SONY PARTS WHOSE
PART NUMBERS APPEAR AS SHOWN IN THIS MANUAL OR
IN SUPPLEMENTS PUBLISHED BY SONY.
Fig. A. Using an AC voltmeter to check AC leakage.
1.5 k Ω 0.15 µ FAC
voltmete
r
(0.75 V)
To Exposed Metal
Parts on Set
Earth Ground
ATTENTION AU COMPOSANT AYANT RAPPORT
À LA SÉCURITÉ!
LES COMPOSANTS IDENTIFIÉS PAR UNE MARQUE 0SUR
LES DIAGRAMMES SCHÉMATIQUES ET LA LISTE DES
PIÈCES SONT CRITIQUES POUR LA SÉCURITÉ DE
FONCTIONNEMENT. NE REMPLACER CES COM- POSANTS
QUE PAR DES PIÈCES SONY DONT LES NUMÉROS SONT
DONNÉS DANS CE MANUEL OU DANS LES SUPPLÉMENTS
PUBLIÉS PAR SONY.

3
CMT-A50/A70
TABLE OF CONTENTS
1. SERVICING NOTES ............................................... 4
2. GENERAL ................................................................... 6
3. DISASSEMBLY
3-1. Disassembly Flow ........................................................... 9
3-2. Cabinet Rear .................................................................... 10
3-3. CD Door .......................................................................... 10
3-4. CD Mechanism Deck (FLM-A50) .................................. 11
3-5. SUB Board ...................................................................... 11
3-6. Top Case Assy ................................................................. 12
3-7. MAIN Board.................................................................... 12
3-8. CD Board......................................................................... 13
3-9. Tray.................................................................................. 13
3-10. Optical Pick-up Block
(KSM-213CCP or KSM-213RCP) .................................. 14
3-11. Optical Pick-up (KSS-213C) ........................................... 14
3-12. Optical Pick-up (KSS-213R) ........................................... 15
3-13. Tape Mechanism Deck (CMAL1Z252A)........................ 15
4. TEST MODE.............................................................. 16
5. ELECTRICAL ADJUSTMENTS
Deck Section.................................................................... 18
CD Section ...................................................................... 19
6. DIAGRAMS
6-1. Block Diagram – SERVO Section –............................... 20
6-2. Block Diagram – MAIN Section –................................. 21
6-3. Block Diagram
– PANEL, POWER SUPPLY Section – .......................... 22
6-4. Printed Wiring Board – CD Board – .............................. 24
6-5. Schematic Diagram – CD Board – ................................. 25
6-6. Printed Wiring Board
– MAIN Board (Component Side) – ............................... 26
6-7. Printed Wiring Board
– MAIN Board (Conductor Side) – ................................. 27
6-8. Schematic Diagram – MAIN Board (1/2) – ................... 28
6-9. Schematic Diagram – MAIN Board (2/2) – ................... 29
6-10. Printed Wiring Boards – REGULATOR Section – ........ 30
6-11. Schematic Diagram – REGULATOR Section –............. 31
6-12. Printed Wiring Boards – PANEL, MOTOR Section – ... 32
6-13. Schematic Diagram – PANEL, MOTOR Section –........ 33
6-14. Printed Wiring Boards
– AMP, POWER SUPPLY Section (CMT-A50 only) – .. 34
6-15. Schematic Diagram
– AMP, POWER SUPPLY Section (CMT-A50 only) – .. 35
6-16. Printed Wiring Boards
– AMP Section (CMT-A70 only) – ................................. 36
6-17. Schematic Diagram
– AMP Section (CMT-A70 only) – ................................. 37
6-18. Printed Wiring Board
– POWER SUPPLY Section (CMT-A70 only) – ............ 38
6-19. Schematic Diagram
– POWER SUPPLY Section (CMT-A70 only) – ............ 39
7. EXPLODED VIEWS
7-1. Overall Section ................................................................ 50
7-2. Front Panel Section ......................................................... 51
7-3. Top Case Section ............................................................. 52
7-4. CD Mechanism Deck Section (FLM-A50) ..................... 53
7-5. Optical Pick-up Section (KSM-213CCP)........................ 54
7-6. Optical Pick-up Section (KSM-213RCP)........................ 55
7-7. Speaker (Left) Section (A50) .......................................... 56
7-8. Speaker (Right) Section (A50) ........................................ 57
7-9. Speaker (Left) Section (A70) .......................................... 58
7-10. Speaker (Right) Section (A70) ........................................ 59
8. ELECTRICAL PARTS LIST................................ 60
Ver. 1.2

4
CMT-A50/A70
Power requirements
indication
– Left Speaker Back Panel –
The laser diode in the optical pick-up block may suffer electrostatic
break-down because of the potential difference generated by the
charged electrostatic load, etc. on clothing and the human body.
During repair, pay attention to electrostatic break-down and also
use the procedure in the printed matter which is included in the
repair parts.
The flexible board is easily damaged and should be handled with
care.
NOTES ON LASER DIODE EMISSION CHECK
The laser beam on this model is concentrated so as to be focused on
the disc reflective surface by the objective lens in the optical pick-
up block. Therefore, when checking the laser diode emission,
observe from more than 30 cm away from the objective lens.
NOTES ON HANDLING THE OPTICAL PICK-UP
BLOCK OR BASE UNIT
SECTION 1
SERVICING NOTES
•MODEL IDENTIFICATION
Model Destination Power Requirements
Indication
CMT-A50
AEP, UK, Italian,
AC: 230V-50Hz 50W
East European
and Russian models
Korean model AC: 220V-60Hz 50W
CMT-A70
US and Canadian model AC: 120V 60Hz 100W
AEP, UK, Italian,
East European, Russian AC: 230V-50Hz 100W
and Australian models
HOW TO OPEN THE CD TRAY WHEN POWER SWITCH TURNS OFF.
1 Using a flat-tip screwdriver of the diameter
less than 4 mm, rotate the gear in the arrow
direction.
2 Pull-out the CD tray.
Ver. 1.1

5
CMT-A50/A70
Changing the resume
play setting
The player is initially set to start playback
from the point you last stopped playing
(resume play)
You can cancel resume play and the player
always will start from the first track.
DISPLAY
1Press DISPLAY when the player is
turned off.
2Turn the jog dial to select “CD
RESUME OFF”.
“OFF” flashes on the display.
3Press the jog dial to enter the selection.
To go back to the clock display, press
the jog dial again.
To reset the resume play
function
In step 2 above turn the jog dial until “CD
RESUME ON” appears and then press the
jog dial twice.
Jog dial
(PUSH ENTER/
MEMORY)
Adjusting the contrast
of the display
+
1 Press DISPLAY when the player is
turned off.
The MENU display appears.
2 Press the jog dial or + to select
“CONTRAST”.
The contrast digits (1 - 32) flash on the
display.
3 Turn the jog dial to select the number
for the contrast you want while
observing the display.
4 Press the jog dial to enter the selection.
Jog dial (PUSH
ENTER/
MEMORY) DISPLAY
KSM-213CCP
There is gear cover.
HOW TO IDENTIFY KSM-213CCP AND KSM-213RCP
KSM-213RCP
There is not gear cover.

6
CMT-A50/A70 SECTION 2
GENERAL This section is extracted from
instruction manual.
6
GB
Playing a CD
For hookup instructions.
1Press ZOPEN/CLOSE (direct
power-on) and place the CD on the
CD tray.
2Press ZOPEN/CLOSE to close the
CD tray.
With the label side up
1, 2 3
Basic Operations
Basic Operations
7
GB
Playing timeTrack number Playing time
3Press CD u(uon the remote).
The player plays all the tracks once.
**When playing an MP3 CD,
“MP3” appears on the display.
File number
continued
Display
Audio CD
CD u
?/1
VOLUME
STOP x
Use these buttons for additional operations
To Do this
adjust the volume Turn the VOLUME control. (Press
VOL +*
1
, – on the remote.)
stop playback Press STOP x(xon the remote).
pause playback Press CD u*
2
(uon the remote).
The playing time of the current track/file
flashes on the display.
Press the button again to resume play after
pause.
go to the next track Press M/>.
go back to the Press ./m.
previous track
*
1
The button has a tactile dot.
*
2
There is a tactile dot beside CD uon the main unit.
Tips
•To listen through
headphones, connect the
headphones to the i
(headphones) jack.
•Playback starts from the
point you last stopped
playing (Resume play).
During stop, the point to be
played is displayed.
To start play from the
beginning of the first track,
press STOP xin stop
mode.
To cancel the resume play.
File name
ATRAC CD/MP3 CD**
ZOPEN/CLOSE
M/>
./m
–, +
Note
Before playing an ATRAC
CD/MP3 CD, this player
reads all file and group
information on the CD.
Depending on the file
structure, it may take more
than a minute to read them.
During this time, “Reading”
is displayed.
Track name*
*When playing an audio CD
containing text information
such as CD-TEXT, track name
appears on the display.
8
GB
Notes
•If ATRAC3plus/ATRAC3
files and MP3 files are
recorded on the same CD,
this CD player plays the
ATRAC3plus/ATRAC3
only.
•The playback capability of
this CD player may vary
depending on the quality of
the disc and the condition of
the recording device.
•Characters that can be
displayed on this CD player
are listed below.
–AtoZ
–atoz
–0to9
–!"# $ % & ' ( ) * + , - . / :
; < = > ? @ [ \ ] ^ _ ` { | }
~
If you use other characters
on your computer using
software such as
SonicStage, they are
displayed as “–” on this CD
player.
•On a disc that has
ATRAC3plus/ATRAC3/
MP3 files, do not save files
in other formats and do not
make unnecessary groups.
ATRAC CD
To Press
select a group*
3
+ to go forward and – to go
backward
select a file*
3
M/> to go forward and ./m to
go backward
remove the CD ZOPEN/CLOSE*
4
turn on/off the player ?/1
*
3
You can operate during play of ATRAC CDs/MP3 CDs.
*
4
Once you open the CD tray, the track to start play will change to
the beginning of the first track.
The structure of ATRAC CDs/MP3 CDs
ATRAC CDs/MP3 CDs consist of “files” and “groups.” A
“file” is equivalent to a “track” of an audio CD. A “group”
is a bundle of files and is equivalent to an “album.”
For MP3 CDs, this CD player recognizes an MP3 folder as
a “group” so that ATRAC CDs and MP3 CDs can be
operated in the same way.
Playing order of ATRAC CDs and MP3 CDs
For ATRAC CDs, files are played in the order selected in
SonicStage.
For MP3 CDs, the playing order may differ depending on
the method used to record MP3 files on the disc. In the
following example, files are played in order of 1to 7.
File
Group
MP3 CD
Playing a CD
(continued)
Basic Operations
9
GB
Notes on ATRAC CDs
•Maximum number of groups: 255
Maximum number of files: 999
•CD-Rs/CD-RWs recorded in the ATRAC3plus/ATRAC3 format
cannot be played on your computer.
Notes on MP3 CDs
•Maximum number of groups: 100
Maximum number of files: 400
Maximum directory level: 8
•Agroup that does not include an MP3 file is skipped.
•Be sure to add the file extension “mp3” to the file name.
However, if you add the file extension “mp3” to a file other than
an MP3 file, the player will not be able to recognize the file
properly.
• This player can play bit rates of 16 to 320 kbps, and sampling
frequencies of 32/44.1/ 48 kHz. Variable Bit Rate (VBR) file
can also be played.
•To compress a source in an MP3 file, we recommend setting the
compression parameters to “44.1 kHz,” “128 kbps,” and
“Constant Bit Rate.”
•To record up to the maximum capacity, set the writing software
to “halting of writing.”
•To record to the maximum capacity at one time up on media that
has nothing recorded on it, set the writing software to “Disc at
Once.”

7
CMT-A50/A70
10
GB
Listening to the radio
For hookup instructions.
1Press TUNER BAND•AUTO
PRESET (BAND on the remote)
repeatedly until the band you want
appears on the display (direct power-
on).
2Press TUNING + or TUNING – and
hold it until the frequency digits
begin to change on the display.
The player automatically scans the
radio frequencies and stops when it
finds a clear station.
If you cannot tune in a station, press
TUNING + or TUNING – repeatedly
to change the frequency step by step.
1 2
Display
Indicates an FM
stereo broadcast
Basic Operations
11
GB
Use these buttons for additional operations
Tips
•If the FM broadcast is
noisy, press MODE/DIR
(MODE on the remote)
repeatedly until “Mono”
appears on the display and
radio will play in monaural.
•If you need to change the
AM tuning interval.
•When you tune in an FM
station that provides RDS
(Radio Data System)
services, “R•D•S” and the
name of the station appear
on the display (European
model only). For details.
To Do this
adjust the volume Turn the VOLUME control. (Press
VOL +*, – on the remote.)
turn on/off the radio Press ?/1.
*The button has a tactile dot.
To improve broadcast reception
FM
Keep the FM lead aerial as horizontal as possible and
reorient it.
AM
Keep theAM loop aerial away as far as possible from the
?/1
VOLUME
MODE/DIR
player and reorient it.
12
GB
Playing a tape
For hookup instructions.
1Press ZPUSH OPEN/CLOSE to
open the tape compartment and insert
a recorded tape. Use TYPE I
(normal) tape only .
2Press ZPUSH OPEN/CLOSE to
close the compartment.
3Press TAPE Y(Yon the
remote).
The player turns on (direct power-on)
and starts playing.
Display
1, 2 3
With the side you want
to play facing up
Basic Operations
13
GB
Use these buttons for additional operations
To Do this
adjust the volume Turn the VOLUME control.
(Press VOL +*, – on the remote.)
stop playback Press STOP x(xon the remote).
play the reverse side Press TAPE Y(Yon the remote).
fast-forward or rewind Press M/> or ./m.
the tape
eject the cassette Press ZPUSH OPEN/CLOSE.
turn on/off the player Press ?/1.
*The button has a tactile dot.
To select the direction mode of the tape
Press MODE/DIR repeatedly (MODE on the remote).
To play Display shows
one side of the tape g
both sides of the tape h
from the upper side to reverse
side
both sides of the tape repeatedly j
MODE/DIR
TAPE Y
STOP x
VOLUME
./m, M/>
?/1
Z
CLOSE
PUSH OPEN/

8
CMT-A50/A70
30
The Timer
Setting the clock
“– –:– –” indicator appears on the display
until you set the clock.
CLOCK
Before you begin, hook up the system.
1 Press and hold CLOCK until the hour
digit flashes.
2 Set the clock.
1Turn the jog dial to set the hour and
press it.
2Turn the jog dial to set the minutes.
3 Press the jog dial.
The clock starts from 00 seconds.
Jog dial
(PUSH ENTER/
MEMORY)
Note
If you disconnect the AC power cord, the clock
display may return to “– –:– –”. In this case set the
clock again.
Tip
The time display system of this player is the 12-
hour system.
AM 12:00 = midnight
PM 12:00 = noon
To check the present time
Press CLOCK to display the clock, and press
it again to go back to the previous display.

CMT-A50/A70
9
•This set can be disassembled in the order shown below.
3-1. DISASSEMBLY FLOW
SECTION 3
DISASSEMBLY
3-2. CABINET REAR
(Page 10) 3-3. CD DOOR (Page 10)
3-8. CD BOARD
(Page 13) 3-9. TRAY (Page 13)
3-5. SUB BOARD
(Page 11)
3-7. MAIN BOARD
(Page 12)
3-6. TOP CASE
ASSY
(Page 12)
3-4. CD MECHANISM DECK
(FLM-A50)
(Page 11)
3-10. OPTICAL PICK-UP BLOCK
(KSM-213CCP or KSM-213RCP)
(Page 14)
3-11. OPTICAL PICK-UP
(KSS-213C)
(Page 14)
3-12. OPTICAL PICK-UP
(KSS-213R)
(Page 15)
3-13. TAPE MECHANISM DECK
(CMAL1Z252A)
(Page 15)
SET Note 1: The process described in can be performed in any order.
Note 2: Without completing the process described in , the next process can not be performed.

CMT-A50/A70
10
3-3. CD DOOR
Note: Follow the disassembly procedure in the numerical order given.
3-2. CABINET REAR
7 two screws
5 two screws
6 two stickets
4 two stickets
2 three screws
(BVTP3
× 10)
1 screw
(BVTP3
× 6)
1 screw
(BVTP3
× 6)
8 cabinet rear
3 two screws
(BVTP3
× 10)
1 Using a flat-tip screwdriver of the diameter
less than 4 mm, rotate the gear in the arrow
direction.
gear
2
3
three claws
4 CD door
Ver. 1.1

CMT-A50/A70
11
3-4. CD MECHANISM DECK
(FLM-A50)
3-5. SUB BOARD
1 flexible flat cable (29 core
)
(CN702)
2 connector
(CN306)
2 connector
(CN310)
3 two screws
(BVTP3
× 10)
4 CD mechanism deck
(FLM-A50)
1 screw (BVTP3 × 8)
2 harness
3 connector
(CN309)
4 SUB board

CMT-A50/A70
12
3-6. TOP CASE ASSY
3-7. MAIN BOARD
1 flexible flat cable (8 core)
(CN303)
2 connector
(CN302)
2 connector
(CNP304)
3 boss
3 boss
4 top case assy
1 flexible flat cable
(29 core) (CNF307
)
1 flexible flat cable
(25 core) (CN305)
2 connector
(CN311)
2 connector
(CN310)
2 connector
(CN306)
3 claw
3 claw
4 MAIN board

CMT-A50/A70
13
3-8. CD BOARD
1 Remove four
solders.
2 screw
3
4
wire (flat type)
(16 core) (CN701)
5 CD boar
d
1 two screws
(P2.6
× 8)
2 chuck plate assy
3 Rotate the gear
in the direction of arrow.
4
5
two claws
6 tray
gear
3-9. TRAY

CMT-A50/A70
14
3-10. OPTICAL PICK-UP BLOCK
(KSM-213CCP or KSM-213RCP)
2 screw
(PWH2.6
× 10)
3 drive gear
4 two screws
(PWH2.6
× 10)
1 two screws
(PWH2.6
× 10)
5 two bosses
6 arm
7 vibration proof
rubber (green)
7 vibration proof
rubber (green)
8 vibration proof
rubber (red)
8 vibration proof
rubber (red)
9 optical pick-up block
(KSM-213CCP or KSM-213RCP
)
3-11. OPTICAL PICK-UP
(KSS-213C)
1 gear (A)
2 gear (B) (RP)
4 optical pick-up
(KSS-213C)
3 sled shaft
Ver. 1.1

CMT-A50/A70
15
3-12. OPTICAL PICK-UP (KSS-213R)
3-13. TAPE MECHANISM DECK
(CMAL1Z252A)
2 two screws (M2)
1 gear (B)
4 sled shaf
t
5 optical pick-up
(KSS-213R)
3
1 four screws
(BVTP3
× 10)
2 Open the top case.
3
4
two screws
(PTT2.6
× 6)
5 head shield
6 tape mechanism deck
(CMAL1Z252A)

16
CMT-A50/A70 SECTION 4
TEST MODE
CD TEST MODE
1. EnteringThe CDTest Mode
Procedure:
1. Press the I/1button to turn the power on, and [FUNCTION]
button to select the CD function.
2. Load a disc for test.
3. Press the three buttons of x, [MODE/DIR] and [CLOCK]
simultaneously.
4. Enter the CD Test Mode and display “88” on the LCD.
5. In the CD Test Mode, it changes mode as following figure.
6. In the mode of except FOCUS2 mode, press the ./m
or M/>button to move the sled motor.
CD Test Mode flow:
( ) number: display number
2. ReleasingThe CDTest Mode
To release this mode, press the [DISPLAY] button for to seconds in
the mode of STOP1, STOP2 or STOP3. Or disconnect theAC plug.
INITIAL MODE
(88)
STOP1 MODE
(81)
STOP2 MODE
(82)
x
x
x
x
x
x
x
x
CD u
CD u
CD u
CD u
CD u
CD u
CD u
automatic
transition
[DISPLAY]
[DISPLAY]
[DISPLAY]
[DISPLAY]
[MODE/DIR]
[MODE/DIR]
FOCUS1 MODE
(F-)
ALL SERVO MODE
(P-)
AUTO MODE
(A-)
T. G UP MODE
(P- GUP)
E-F ADJ1 MODE
(E1)
(Not used in servicing)
FG/TG ADJ1 MODE
(E2)
STOP3 MODE
(83)
FOCUS2 MODE
(FC)
RW MODE
(RW)
CD u
x
xCD u
F.B ADJ1 MODE
(E3)
RF AVE MODE
(E4)
CD u
x
xCD u
FE/TE AVE MODE
(E5)
RFDC PK1 MODE
(E6)
CD u
x
xCD u
FCS PRM MODE
(10)
TRK PRM MODE
(20)
CD u
x
E-F ADJ2 MODE
(P1) or (F1)
CD ux
xCD u
SLD PRM MODE
(30)
CLV PRM MODE
(40)
CD u
x
xCD u
DFT PRM MODE
(50)
MON PRM MODE
(60)
CD u
x
xCD u
RFDC PK2 MODE
(E7)
FZC MON MODE
(E8)
CD u
x
[MODE/DIR]
[MODE/DIR]
[MODE/DIR]
[MODE/DIR]
[MODE/DIR]
[MODE/DIR]
[MODE/DIR]
[MODE/DIR]
[MODE/DIR]
[MODE/DIR]
[MODE/DIR]
[MODE/DIR]
[MODE/DIR]
[MODE/DIR]
[MODE/DIR]
[MODE/DIR]
[MODE/DIR]
[MODE/DIR]
FG/TG ADJ2 MODE
(P2) or (F2)
CD ux
F.B ADJ2 MODE
(P3) or (F3)
CD ux

17
CMT-A50/A70
DISPLAY TEST MODE
Procedure:
1. Press the I/1button to turn the power on.
2. Press the three buttons of x, [MODE/DIR] and [TIMER]
simultaneously.
3. Enter the Display Test Mode and display the version of
microcomputer (IC309 on the MAIN board) for 10 seconds.
4. Then lights up the all segments and all off alternately every 10
seconds.
5. To release this mode, press the [DISPLAY] buttonfor2 seconds.

18
CMT-A50/A70
– MAIN BOARD (Component Side) –
RV201
RV101
SECTION 5
ELECTRICAL ADJUSTMENTS
•Precaution
1. The adjustment should be performed with the rated power
supply voltage.
2. The adjustments should be performed for both L-ch and R-ch.
0 dB = 0.775 V
DECK SECTION
REC BIAS ADJUSTMENT
Procedure:
1. Record mode
2. Mode: Playback
3. Confirm playback the signal recorded in step 1 become
adjustment level as follows.
4. If these levels do not adjustment level, adjustment the RV101
(L-ch) and RV201 (R-ch) to repeat steps 1 and 4.
Adjustment level: Playback output of 315 Hz to playback output
of 10 kHz: 0 ±1.0 dB (0 ±4.5mV).
+
–
set
recorded
portion
SUB board
CN312 (pin
4 : L-CH)
(pin
3 : R-CH
)
level meter
attenuator
set
MAIN board
LINE IN jack (J301)
1) 315 Hz
2) 10 kHz 50 mV (–23.8 dB)



600 Ω
blank tape
CN-123
AF OSC
Adjustment Location:
1
CN312
– SUB BOARD (Conductor Side) –
2
1516

CMT-A50/A70
1919
CMT-A50/A70
– CD Board (Conductor Side) –
TP
(VC)
TP
(TE)
TP
(RF)
IC702
CD SECTION
Note:
1. Perform all CD section check in the CD Test Mode.
(Refer to page 16)
2. Use the PATD-012 disc (Part No.: 4-225-203-01).
3. Use an oscilloscope with more than 10 MΩimpedance.
4. Clean the object lens by an applicator with neutral detergent when the
signal level is low than specified value with the following checks.
TRAVERSE CHECK
Procedure:
1. Connect an oscilloscope to TP (TE) and TP (VC) on the CD
board.
2. Load the disc (PATD-012).
3. Press the three buttons of x, [MODE/DIR] and [CLOCK]
simultaneously to enter the CD Test Mode and display “88”
(Initial mode).
4. Press the CD ubutton to enter the FOCUS1 mode and
display “F-”.
5. Confirm that the center level of waveform is 0V.
6. Confirm that the Vp-p value of waveform is 0.35 to 1.1 V.
FOCUS BIAS CHECK
Procedure:
1. Connect an oscilloscope to TP (RF) and TP (VC) on the CD
board.
2. In the FOCUS1 mode, press the CD ubutton to enter the
ALL SERVO mode and display “P-”.
3. Confirm that the oscilloscope waveform is as shown in the
below figure. (eye pattern)
A good eye pattern means that the diamond shape “◊” in the
center of the waveform can be clearly distinguished.
CD board
TP (TE)
TP (VC) +
–
oscilloscop
e
(DC range)
CD board
TP (RF)
TP (VC) +
–
oscilloscop
e
(AC range)
VOLT/DIV:0.2 V (with the 10:1 probe in use)
TIME/DIV: 1 ms
0 V Vp-p
VOLT/DIV: 0.2 V (with the 10: 1 probe in use.)
TIME/DIV: 200 ns
0.6 to 1.2 Vp-p
When observing the eye pattern, set the oscilloscope
for AC range and raise vertical sensitivity.
Checking Location:

CMT-A50/A70
2020
CMT-A50/A70
SECTION 6
DIAGRAMS
6-1. BLOCK DIAGRAM – SERVO Section –
C
D
E
F
LD
VC
VCC
10
B
11
A
12
13
14
9
16
15 CD +3.3V
GND
PD
VR
FOCUS
COIL
TRACKING
COIL
RF AMP, FOCUS/TRACKING
ERROR AMP
IC701
OPTICAL PICK-UP
BLOCK
(KSS-213C)
VC
27
A
6
B
7
C
8
D
9
E
10
F
11
LD
1
PD
2
COIL/MOTOR DRIVE
IC704
F+
13
F–
12
T+
2
T–
1
SL+
16
SL–
17
M701
(SLED)
M702
(SPINDLE)
SP+
26
SP–
27
F+
F-
T+
T-
9
10
5
4
20
SFDR
19
SRDR
TFDR
TRDR
FFDR
FRDR
24
SPIN
15
MUTE
MDP
103
SRDR
99
SFDR
100
TRDR
97
TFDR
98
FRDR
95
FFDR
96
CD DSP
IC702
RFAC
84
29
RFDCI
28
RFDC
16
FE
17
FEI
12
SW
RFDC
88
FE
92
TE
90
SE
91
109
PCMDI
21
DATA
R-CH
20
CLOK
23
XLAT
27
SCOR
28
XRST
CD_DATA (O)
19
CD_CLK (O)
20
CD_XLAT
21
24
XSOE CD_XSOE
8
CD_SCOR
47
22
SENS CD_SENS
18
65
FOK CD_FOK
1
69
GFS/MNT2/
XROF CD_GFS
2
SYSTEM CONTROLLER
IC309 (1/3)
15
RF AC
18
TE
MP3 DECODER
IC703
PCMDO
15
111
BCKI BCKO
13
107
LRCKI LRCKO
14
108
PCMD PCMDI
4
110
BCK BCKI
2
51
AOUT1
56
AOUT2
106
LRCK LRCKI
1
18
XRDE XRDE
12
47
XTAI
48
XTAO
XTAL
30
EXTAL
29
40
SDOUT
SDIN
38
SDCLKI
42SDXLATI
33
NRSTI
37
RDENO
41
62
DOUT
CD_XWAKE
CD_SDXLAT
10
CD_RDEN
52
34 13
CD_NRST
12
CD_LDON
9
XWAKEI
CD_PWM RF
5
CD_PWM TE
6
CD_PWM FE
7
CD_RW/ROM
4
X701
16.9344MHz
S701
(LIMIT)
X702
22.58MHz
CD_XRST
3
AUTOMATIC
POWER CONTROL
Q701, 702
LOADING MOTOR
DRIVE
IC651
M
M
CD-L
A
101
SSTP
D0
D3
A0
A10
XRAS 5
D-RAM
IC705
2XWE
9XCAS
1XRAS
A0
A10
2
3
22
23
.
.
.
XWE 4
XCAS 21
D0
D3
17
15
13
.
11
.
116
113
.
117
8
11
14
.
19
7
.
4
3
6
5
.
.
.
OPTICAL
DIGITAL
OUT (CD)
J302
1
S651 OPEN
CLOSE
M651
(LOADING)
TRAY OPEN/CLOSE
DETECT
()
: CD PLAY (ANALOG OUT)
R-ch is omitted due to same as L-ch.
SIGNAL PATH
: CD PLAY (DIGITAL OUT)
CD_SDIN
58
CD_SDOUT
59
CD_SDCK
60
CD_OPEN
CD_CLOSE
16
15
CD_OPENIN
CD_CLOSEIN
17
14
MM
(Page 21)