Sony CDFZW-755 Service manual
CFD-ZW755
SERVICE MANUAL
Ver 1.0 2000.03
CD
Section
TC
Section
US Model
Model Name Using Similar Mechanism CFD-ZW750/ZW770
CD Machanism Type KSM-213CDM
Optical Pick-up Type KSS-213C
Model Name Using Similar Machanism NEW
T ape Transport Mechanism T ype MF-ZW755-117
SPECIFICATIONS
AUDIO POWER SPECIFICATIONS
POWER OUTPUT AND TOTAL HARMONIC DISTORTION
With 3.2-ohm loads, both channel driven from 150 - 6,300 Hz; rated 1.6
W per channel-minimum RMS power, with no more than
10 % total harmonic distortion in AC operation.
Other Specifications
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
200 r/min (rpm) to 500 r/min (rpm) (CLV)
Number of channels
2
Frequency response
20 - 20,000 Hz +1/–1 dB
Wow and flutter
Below measurable limit
Radio section
Frequency range
FM: 87.5 - 108 MHz
AM:530 - 1,710 kHz
Antennas
FM: Telescopic antenna
AM: Built-in ferrite bar antenna
Cassette-corder section
Recording system
4-track 2 channel stereo
Fast winding time
Approx. 120 s (sec.) with Sony cassette C-60
Frequency response
TYPE I (normal): 80 - 10,000 Hz
General
Speaker
Full range: 10 cm (4 in.) dia.,
3.2 ohms, cone type (2)
Outputs
Headphones jack (stereo minijack)
For 16 - 68 ohms impedance headphones
Power requirements
For CD radio cassette-corder:
120 V AC, 60 Hz
9 V DC, 6 size D (R20) batteries
For memory back-up:
4.5 V DC, 3 size AA (R6) batteries
For remote control:
3 V DC, 2 size AA (R6) batteries
– Continued on page 2 –
CD RADIO CASSETTE-CORDER
Power consumption
AC 15 W
Battery life
For CD radio cassette-corder:
FM recording
Sony R20P: approx. 7.5 h
Sony alkaline LR20: approx. 22 h
Tape playback
Sony R20P: approx. 7 h
Sony alkaline LR20: approx. 20 h
CD playback
Sony R20P: approx. 3 h
Sony alkaline LR20: approx. 10 h
For memory back-up: approx. 1 year
Dimensions
Approx. 650 x 265 x 256 mm (w/h/d)
(25 5⁄8 x 10 1⁄2 x 10 1⁄8 inches) (incl. projecting parts)
Mass
Approx. 6.7 kg (14 lb. 12 oz) (incl. batteries)
Supplied accessory
AC power cord (1)
Remote control (1)
Design and specifications are subject to change without notice.
CAUTION
Use of controls or adjustments or performance
of procedures other than those specified herein
may result in hazardous radiation exposure.
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.
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.
NOTES ON HANDLING THE OPTICAL PICK-UP
BLOCK OR BASE UNIT
The laser diode in the optical pick-up block may suffer electrostatic breakdown because of the potential difference generated
by the charged electrostatic load, etc. on clothing and the human
body.
During repair, pay attention to electrostatic breakdown 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.
TABLE OF CONTENTS
Specifications ........................................................................... 1
1. SERVICING NOTES ....................................................3
2. GENERAL....................................................................... 4
3. DISASSEMBLY
3-1. Cabinet (Rear) .......................................................... 6
3-2. Power Board, Back up Board, Battery Board........... 6
3-3. CD Block ASSY....................................................... 7
3-4. Control Board ........................................................... 7
3-5. Power Key Board, Mega Bass Board,
Preset Board, Volume Board ..................................... 8
3-6. Key Board................................................................. 8
3-7. Headphone Board ..................................................... 8
3-8. REC SW Board, PB Board ....................................... 9
3-9. Mechanism Deck ...................................................... 9
3-10. Capstan/reel Motor (M301), Belt ........................... 10
3-11. Main Board ............................................................. 10
3-12. CD Board .................................................................11
3-13. Optical pick-up Block ............................................. 11
4. ADJUSTMENTS
4-1. Mechanical Adjustments........................................... 12
4-2. Electrical Adjustments.............................................. 12
5. DIAGRAMS
5-1. Explanation of IC Terminals ..................................... 15
5-2. Block Diagrams ........................................................ 17
5-3. Schematic Diagram (Main Section) ......................... 21
5-4. Printed Wiring Boards (Main Section) ..................... 25
5-5. Printed Wiring Boards (Control Section) ................. 28
5-6. Schematic Diagram (Control Section)...................... 31
5-7. Printed Wiring Boards (CD Section)........................ 34
5-8. Schematic Diagram (CD Section) ............................ 37
6. EXPLODED VIEWS
6-1. Rear Cabinet Section............................................... 44
6-2. Front Cabinet Section.............................................. 45
6-3. CD Section .............................................................. 46
6-4. Tape Mechanism Section-1 (MF-ZW755-117)....... 47
6-5. Tape Mechanism Section-2 (DECK A)
(MF-ZW755-117) ................................................... 48
6-6. Tape Mechanism Section-3 (DECK A)
(MF-ZW755-117) ................................................... 49
6-7. Tape Mechanism Section-4 (DECK B)
(MF-ZW755-117) ................................................... 50
6-8. Tape Mechanism Section-5 (DECK B)
(MF-ZW755-117) ................................................... 51
6-9. Optical pick-up Section (KSM-213CDM) .............. 52
6-10.Speaker Section ....................................................... 53
7. ELECTRICAL PARTS LIST.................................... 54
SAFETY-RELATED COMPONENT WARNING!!
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 more than 30 cm away from the objective
lens.
COMPONENTS IDENTIFIED BY MARK ! OR DO TTED LINE WITH
MARK ! ON 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.
– 2 –
SECTION 1
SERVICING NOTES
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 for AC 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 0.5mA (500 microampers).
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-operated AC milliammeter. The Data Precision 245
digital multimeter is suitable for this job.
3. Measuring the voltage drop across a resistor by means of a VOM
or battery-operated AC voltmeter . 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)
CHUCK PLATE JIG ON REPAIRING
On repairing CD section, playing a disc without the CD lid, use
Chuck Plate Jig.
• Code number of Chuck Plate Jig : X-4918-255-1
LASER DIODE AND FOCUS SEARCH OPERATION
CHECK
1. Turn on POWER button and press CD button to CD
position.
2. Open the CD lid.
3. Turn on S901 as following figure.
4. Confirm the laser diode emission while observing the
objecting lens. When there is no emission, Auto Power
Control circuit or Optical Pick-up is broken.
Objective lens moves up and down three for focus search.
Insert a precision
screw driver and push
SWITCH (S901)
To Exposed Metal
Parts on Set
0.15 µF
Fig. A. Using an AC voltmeter to check AC leakage.
1.5kΩ
Earth Ground
AC
voltmeter
(0.75V)
– 3 –
Basic Operations
SECTION 2
GENERAL
This section is extracted from
instruction manual.
Playing a CD
1,2
For hookup instructions, see pages 26 – 28.
1 Push 6 PUSH OPEN/CLOSE
2 Close the lid of the CD
down to open the CD
compartment and place the CD
on the CD compartment.
compartment.
3 Press ^.
The player turns on (direct
power-on) and plays all the tracks
once.
3
With the label side up
Display
Track number Playing time
Tip
Next time you want to
listen to a CD, just press
^. The player turns on
automatically and starts
playing the CD.
Use these buttons for additional operations
POWER 6 PUSH OPEN/CLOSE
^
p
VOLUME
PRESET
TIME SET
To Do this
adjust the volume Turn VOLUME (Press
stop playback Press p.
pause playback Press ^ ( P on the
go to the next track Turn PRESET•TIME SET
go back to the previous track Turn PRESET•TIME SET
remove the CD Press 6 PUSH OPEN/
turn on/off the player Press POWER.
VOL +, – on the remote).
remote).
Press the button again to
resume play after pause.
clockwise (Press + on
the remote).
counterclockwise (Press
=on the remote).
CLOSE.
Basic Operations
Basic Operations4
Listening to the radio
1
For hookup instructions, see pages 26 – 28.
1 Press RADIO BAND until the
2 Hold down TUNE + or – until the
band you want appears in the
display (direct power-on).
Each time you press the button,
the indication changes as follows:
"FM1" n "FM2" n "AM".
frequency digits begin to change
in the display.
The player automatically scans
the radio frequencies and stops
when it finds a clear station.
If you cannot tune in to a station,
press the button repeatedly to
change the frequency step by
step.
2
Display
Indicates an FM stereo
broadcast
Tips
• The "FM1" and "FM2"
bands have the same
functions. You can store
the stations you want
separately in "FM1" and
"FM2".
• If the FM broadcast is
noisy, press MODE until
“Mono” appears in the
display and radio will
play in monaural.
• Next time you want to
listen to the radio, just
press RADIO BAND.
The player turns on
automatically and starts
playing the previous
station.
Basic Operations
Use these buttons for additional operations
POWER MODE
VOLUME
To Do this
adjust the volume Turn VOLUME (Press
turn on/off the radio Press POWER.
To improve broadcast reception
Reorient the antenna for FM. Reorient the player itself
for AM.
for FM
VOL +, – on the remote).
for AM
5
Basic Operations
Basic Operations
6
– 4 –
Basic Operations
7
Playing a tape
Use these buttons for additional operations
12 12
POWER
Basic Operations
0, )
p6
P
VOLUME
0, )
p6
P
For hookup instructions, see pages 26 – 28.
1 Press p6 to open the tape
compartment and insert a
recorded tape. Use TYPE I
(normal) tape only. Close the
compartment.
With the side you want
to play facing you
2 Press (.
The player turns on ( direct
power-on) and starts playing.
Basic Operations8
Recording on a tape
312
Display
Note
During playback, do not
press buttons on the
other deck. Otherwise
the playback speed may
change.
Tip
Next time you want to
listen to a tape, just
press (. The player
turns on automatically
and starts playing the
tape.
Deck B
3 Start recording.
To Do this
adjust the volume Turn VOLUME (Press
stop playback Press p6.
fast-forward or rewind the tape Press ) or 0.
pause playback Press P.
eject the cassette Press p6.
turn on/off the player Press POWER.
To record from the CD player and
the radio, press r on deck B ((
is depressed automatically).
VOL +, – on the remote).
Press the button again to
resume play after pause.
Basic Operations
9
Basic Operations
For hookup instructions, see pages 26 – 28.
1 Press p6 to open the tape
2 Select the program source you
Basic Operations10
compartment on deck B and
insert a blank tape. Use TYPE I
(normal) tape only.
With the side you want to
record on facing you
want to record.
To record from the CD player:
insert a CD (see page 4) and press
CD.
To record from the radio:
tune in the station you want (see
page 6).
To record from the tape (dubbing):
insert a recorded tape into deck A
and press TAPE until “dUb”
appears in the display.
Display
Deck A
Tips
• Adjusting the volume or
the audio emphasis (see
page 25) will not affect
the recording level.
• For the best results, use
the AC power as a
power source.
• If the AM program
makes a whistling
sound after you've
pressed r in step 3,
press MODE repeatedly
until the noise at a
minimum.
To record from the tape, press r
on deck B ((is depressed
automatically). Then press ( on
deck A.
Use these buttons for additional operations
POWER
To Press
stop recording p6 on deck B
pause recording P on deck B
turn on/off the player POWER
To erase a recording, proceed as follows:
1 Insert a tape whose recording you want to erase intodeck
B.
2 Press TAPE untill “TAPE” appears in the display.
3 Press r on deck B.
MODE
Press the button again to
resume recording.
p6
P
Basic Operations
11
– 5 –
SECTION 3
(
)
e
DISASSEMBLY
z
The equipment can be removed using the following procedure.
Cabinet (Rear)
Set
Cabinet (Front)
sub ASSY
Note : Follow the disassembly procedure in the numerical order given.
Power board, Back up board, Battery board
CD block ASSY
Control board
Headphone board
Main board
REC SW board, PB board
Mechanism deck Capstan/reel motor (M301), Belt
Power key board, Mega bass board,
Preset board, Volume board
Key board
CD board Optical pick-up block
3-1. CABINET (REAR)
Cabinet (front) sub ASSY
6
7 CNP901
2 Screws (BVTP 3x10)
1 Handle
Cabinet (rear)
3 Screws (BVTP 3x14)
5 Screw (BVTP 3x14)
3-2. POWER BOARD, BACK UP BOARD, BATTERY BOARD
3 Screws (BVTP 3x10)
5
POWER board
4 Screws (BVTP 3x10)
2 CN904
1 CN903
Back up board
Cabinet (rear)
7
4 Screws
BVTP 3x14
8 Bracket (2), Yok
9
Battery board
6 Claw
– 6 –
3-3. CD BLOCK ASSY
Y
8
1 Screws (BVTP 3x12)
1 Screws (BVTP 3x12)
2 CN310
CD block ASSY
3 To S901
(CD door open/close)
3-4. CONTROL BOARD
2 CN311
2 CN303
4
2 Screws (BVTP 2.6x8)
2 CN306
2 CN305
2 Wire, parallel
(23 core) (CN308)
Cabinet (front) sub ASS
2 Screws (BVTP 2.6x8)
Control board
1 CN807
Cabinet (front) sub ASSY
– 7 –
1 CN806
1 CN80
3
3-5. POWER KEY BOARD, MEGA BASS BOARD, PRESET BOARD, VOLUME BOARD
Y
d
1 Screws (BVTP 2.6x8)
Power key board
qs Screw
(BVTP 2.6x8)
3 Screws (BVTP 2.6x8)
2
Mega bass board
7 Screw (BVTP 2.6x8)
Preset board
Cabinet (front) sub ASS
9
3-6. KEY BOARD
1 Claws
Volume board
qa Nut and washer
qd Claws
4
Control boar
qf
8 Claws
6 Nut and washer
5 Knod, preset
0 Knod, volume
3-7. HEADPHONE BOARD
1 Bracket (2), yoke
Key board
1 Claws
2
Headphone board
2
– 8 –
3-8. REC SW BOARD, PB BOARD
k
3 Screw (BVTP 3x10)
REC SW board
2 Remove solder
WHT
BLK
RED
Shield
4
PB board
1 CN304
6 Screw
(BVTP 3x10)
7
Cabinet (front) sub ASSY
5 Remove solder
WHT
Shield
BLK
3-9. MECHANISM DECK
1 Screws (BVTP 3x10)
Mechanism dec
2
Cabinet (front) sub ASSY
– 9 –
3-10. CAPSTAN/REEL MOTOR (M301), BELT
)
1 Screws (+PTT 2x5)
Chassis (sub)
DECK ASSY, A
1 Screw (+PTT 2x5)
3-11. MAIN BOARD
DECK ASSY, B
3 Belt
2
1 Screws
(+PTT 2x5)
3 Belt
2 Screws (BVTP 3x10)
5 Capstan/reel
motor (M301
4 Screws (M2.6x2.5)
2 Screws (BVTP 3x10)
CD board
CD block ASSY
3
Main board
1 CNP704
– 10 –
3-12. CD BOARD
)
3 Screws (BVTP 3x10)
CD board
CD block ASSY
3 Screws (BVTP 3x10)
4
2 CN702
1 Wire, parallel
(16 core) (CN701
3-13. OPTICAL PICK-UP BLOCK
1 Screws (+PWH 2.6x10)
1 Screws (+PWH 2.6x10)
Optical pick-up block
2
Chassis, CD
– 11 –
y
SECTION 4
p
ADJUSTMENTS
4-1. MECHANICAL ADJUSTMENTS
PRECAUTION
1. Clean the following parts with a denatured-alcohol-moistened
swab :
record/playback head pinch roller
erase head rubber belt
capstan
2. Demagnetize the record/playback head with a head demagnetizer. (Do not bring the head demagnetizer close to the erase
head.)
Do not use a magnetized screwdriver for the adjustments.
3. These measurement adjustment should be performed with the
rated power supply voltage (9 V) unless otherwise noted.
Torque Measurement DECK A DECK B
Mode Torque Meter Meter Reading
Forward
Forward 2 to 5 g • cm
back tension (0.03 – 0.069 oz• inch)
Fast Forward
and CQ-201B
Rewind
CQ-102C
22.5 to 55 g • cm
(0.32 to 0.76 oz• inch)
60 to 120 g • cm
(0.84 – 1.66 oz• inch)
4-2. ELECTRICAL ADJUSTMENTS
TAPE SECTION
Standard Output level
Outout terminal SP OUT PHONES OUT
load impedance 3.2 Ω 32 Ω
output signal level 0.775V (0dB) 0.25V (–10dB)
Test T ape
Type Signal Used for
WS-48A 3kHz, 0 dB Tape Speed Adjustment
Tape Speed Adjustment DECK A DECK B
Procedure :
test tape
WS-48A
(3kHz, 0 dB)
0 dB = 0.775V
digital frequenc
counter
32 Ω
set
PHONES jack (J301)
Tape Tension Measurement DECK A DECK B
Mode Torque Meter Meter Reading
Forward CQ-403A
more than 150 g
(more than 5.3 oz)
1. Playback WS-48A (tape center part) and adjust RV301 so that
the frequency counter reading becomes 3,000Hz.
Standard value : 2,985–3,015Hz
2. Playback WS-48A (tape top and end).
Check that frequency counter reading is within 1.5% of the reading of step 1.
Adjustment Location :
[MAIN BOARD]
(Component side)
RV301 : Ta
e Speed Adjustment
– 12 –
TUNER SECTION
0 dB = 1µV
• FM Section
Setting :
RADIO BAND button : FM
AM RF signal
generator
75 kHz frequency
deviation by 1 kHz signal
Output level : as low as possible
FH1
(antenna terminal)
0.01 µF
• AM Section
Setting :
RADIO BAND button : AM
AM RF signal
generator
30% amplitude modulation by 400Hz
signal.
Output level : as low as possible
Put the lead-wire
antenna close to
the set.
• Connecting Level Meter (FM and AM)
level meter
(range : 0.5 – 5 V ac)
32 Ω
set
(Main board)
• Repeat the procedures in each adjustment several times, and the
frequency coverage and tracking adjustments should be finally
done by the trimmer capacitors.
AM IF ADJUSTMENT
Adjust for a maximum reading on level meter.
T1 450kHz
AM FREQUENCY COVERAGE ADJUSTMENT
Adjust parts Frequency display
L4 530kHz
Confirmation 1,710kHz Standard value : 4.4 – 5.2V
AM TRACKING ADJUSTMENT
Adjust for a maximum reading on level meter.
L3 620kHz
CT2 1,400kHz
FM IF ADJUSTMENT
Adjust for a maximum reading on level meter.
T2 10.7MHz
FM FREQUENCY COVERAGE ADJUSTMENT
Adjust parts Frequency display
Confirmation 87.5MHz Standard value : 1.5 – 2.1V
L2 108MHz
Reading on digital
voltmeter
Adjustment value : 0.8V
Standard value : 0.76 – 0.84V
Reading on digital
voltmeter
Adjustment value : 4.2V
Standard value : 3.9 – 4.5V
set
PHONES jack (J301)
• Connecting Digital Voltmeter (FM and AM)
digital
voltmeter
VT
(JW13)
100K Ω
FM TRACKING ADJUSTMENT
Adjust for a maximum reading on level meter.
L1 87.5MHz
CT1 108MHz
Adjustment Location : Main board (See page 14)
– 13 –
Adjustment Location :
t
JW735
JW736
JW725
JW708
JW718
JW711
1
5
10
13
14
20
2627
30
35
39
40
45
50
52
IC701
C717
C707
C721
C724
C723
C712
C735
C731
C766
C739
C727
C709
R
R755
R710
R747
R726
R728
R72
R718
R701
R702
R704
R706
R720
R721
R717
R733
R742
R745
R74
715
C706
e
L3 : AM Tracking Adjustment
[MAIN BOARD] (Component side)
FH1
CT2 : AM Tracking Adjustment
L4 : AM Frequency Coverage Adjustmen
FM Tracking Adjustment
CT1
L1
CD SECTION
CD section adjustments are done automatically in this set.
In case of operation check, confirm that focus bias.
Focus Bias Check
1. Connect the oscilloscope between IC701 ed pin (RFO) and ta
pin (VC) on CD board.
2. Insert the disc (YEDS-18). (Part No. : 3-702-101-01)
3. Press the u button.
4. Confirm that the oscilloscope waveform is as shown in the figure below. (eye pattern)
A good eye pattern means that the diamond shape (◊) in the center of the waveform can be clearly distinguished.
• RF Signal Reference Waveform (eye pattern)
VOLT/TV : 200mV (10 : 1 probe in use)
TIME/DIV : 500 nS
When observing the eye pattern, set the oscilloscope for AC range
and raise certical sensitivity
RF level
0.9 – 1.5 Vp-p
IC1
T2 : FM IF Adjustment
T1 : AM IF Adjustment
– 14 –
JW13
IC2
VT (JW13)
L2 : FM Frequency Coverage Adjustment
Connection point :
[CD BOARD] (Conductor side)
IC701 pin ed (RFO)
oscilloscop
IC701 pin ta (VC)
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