Sony HCD-VX8 User manual

– 1 –
HCD-VX8/VX8J
E Model
SPECIFICATIONS
Photo: HCD-VX8 (SILVER)
COMPACT DISC DECK RECEIVER
— Continued on next page —
Model Name Using Similar Mechanism HCD-GRX80/RXD8/RXD8S
CD Mechanism Type CDM38L-5BD34L
Base Unit Type BU-5BD34L
Optical Pick-up Type KSS-213D/Q-NP
Model Name Using Similar Mechanism HCD-GRX80/RXD8/RXD8S
Tape Transport Mechanism Type TCM-230AWR2/230PWR2
CD
SECTION
TAPE DECK
SECTION
MICROFILM
SERVICE MANUAL
HCD-VX8/VX8Jisthetuner,deck,CDand
amplifier section in MHC-VX8/VX8J.

– 2 –
NOTES ON HANDLINGTHE OPTICAL PICK-UP BLOCK
OR BASE UNIT
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, ob-
serve from more than 30 cm away from the objective lens.
LASER DIODE AND FOCUS SEARCH OPERATION
CHECK
Carry out the “S curve check” in “CD sectionadjustment” and check
that the S curve waveform is output four times.
4-215-641-0πVX8: EA MALAYSIA
4-215-641-1πVX8: MY, SP MALAYSIA
4-215-641-2πVX8: TW MALAYSIA
4-215-641-3πVX8: E MALAYSIA
4-215-641-4πVX8: IA INDONESIA
4-215-641-5πVX8: HK MALAYSIA
4-215-641-6πVX8J: E JAPAN
4-215-641-7πVX8J: EA JAPAN
4-215-641-8πVX8: TH THAI
MODEL IDENTIFICATION
— BACK PANEL —
• Abbreviation
EA : Saudi Arabia model
TW : Taiwan model
IA : Indonesia model
HK : Hong Kong model
TH : Thai model
MY : Malaysia model
SP : Singapore model
CAUTION
Use of controls or adjustments or performance of procedures
other than those specified herein may result in hazardous ra-
diation exposure.
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 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.
SAFETY-RELATED COMPONENT WARNING !!
COMPONENTS IDENTIFIED BY MARK !OR DOTTED 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.
Laser component in this product is capable of emitting radiation
exceeding the limit for Class 1.
This appliance is classified as
a CLASS 1 LASER product.
The CLASS 1 LASER PROD-
UCT MARKING is located on
the rear exterior.
Parts No.
PARTS No. MODEL PRODUCT
COUNTRY

– 3 –
TABLE OF CONTENTS
1. SERVICING NOTE .......................................................... 4
2. GENERAL .......................................................................... 5
3. DISASSEMBLY
3-1. Loading Panel ....................................................................... 7
3-2. Front Panel and Video Board ................................................ 7
3-3. Cassette Lid and Tape Mechanism........................................ 8
3-4. CD SW Board and Panel Board............................................ 8
3-5. Disc Tray ............................................................................... 9
4. SERVICE MODE ............................................................ 10
5.TEST MODE ..................................................................... 12
6. MECHANICAL ADJUSTMENTS ..........................13
7. ELECTRICAL ADJUSTMENTS ............................... 13
8. DIAGRAMS
8-1. Circuit Boards Location ...................................................... 18
8-2. Block Diagrams
• CD Section ....................................................................... 19
• Video Section ................................................................... 21
• Deck Section .................................................................... 23
• Main Section .................................................................... 25
• Power Section .................................................................. 27
• Display Section ................................................................ 29
8-3. Printed Wiring Board – CD Section –................................. 33
8-4. Schematic Diagram – CD Section – ................................... 35
8-5. Schematic Diagram – Deck Section –................................. 37
8-6. Printed Wiring Board – Deck Section – .............................. 39
8-7. Printed Wiring Board – Video Section – ............................. 41
8-8. Schematic Diagram – Video (1/3) Section – ....................... 43
8-9. Schematic Diagram – Video (2/3) Section – ....................... 45
8-10. Schematic Diagram – Video (3/3) Section – .................... 47
8-11. Printed Wiring Board – Main Section – ........................... 49
8-12. Schematic Diagram – Main (1/4) Section – ..................... 51
8-13. Schematic Diagram – Main (2/4) Section – ..................... 53
8-14. Schematic Diagram – Main (3/4) Section – ..................... 55
8-15. Schematic Diagram – Main (4/4) Section – ..................... 57
8-16. Printed Wiring Board – Leaf SW Section – ..................... 59
8-17. Schematic Diagram – Leaf SW Section – ........................ 59
8-18. Printed Wiring Board – Panel Section – ........................... 61
8-19. Schematic Diagram – Panel (1/3) Section –..................... 63
8-20. Schematic Diagram – Panel (2/3) Section –..................... 65
8-21. Schematic Diagram – Panel (3/3) Section –..................... 67
8-22. Schematic Diagram – CD Motor Section –...................... 69
8-23. Printed Wiring Board – CD Motor Section – ................... 71
8-24. Schematic Diagram – Trans Section – ............................. 73
8-25. Printed Wiring Board – Trans Section – ........................... 75
8-26. Schematic Diagram – Surround Section – ....................... 76
8-27. Printed Wiring Board – Surround Section –..................... 76
8-28. IC Block Diagrams ........................................................... 77
8-29. IC Pin Functions ............................................................... 80
9. EXPLODEDVIEWS
9-1. Case Section ........................................................................ 90
9-2. Chassis Section ................................................................... 91
9-3. Front Panel Section ............................................................. 92
9-4. CD Mechanism Deck Section-1 (CDM38L-5BD34L) ....... 93
9-5. CD Mechanism Deck Section-2 (CDM38L-5BD34L) ....... 94
9-6. Base Unit Section (BU-5BD34L) ....................................... 95
9-7. TC Mechanism Section-1 (TCM230AWR2/230PWR2) .... 96
9-8. TC Mechanism Section-2 (TCM230AWR2/230PWR2) .... 97
10. ELECTRICAL PARTS LIST .............................98

– 4 –
CD-TEXT
This unit is provided with a simple CD-TEXT display function.
The CD-TEXT contents of 20 tracks are displayed on the fluorescent display tube.
Since the function is simple, some special characters may not be displayed, or may be displayed as other characters.
SECTION 1
SERVICING NOTE
HOW TO OPENTHE DISC TRAY WHEN POWER SWITCH
TURNS OFF
NOTE FOR INSTALLATION (ROTARY ENCODER)
3 Pull-out the disc tray.
1 Remove the Case.
2 Turn the cam to the direction
of arrow.
BU cam
Groove Section A
Note:When attaching the Base unit, Insert the
section A into the groove of BU cam.
Note:When attaching the BU cam,
engage the Rotary encoder
switch as shown in the figure.

– 5 –
LOCATION OF PARTS AND CONTROLS
11/u (Power) button and indicator
2DEMO (STANDBY) button
3DISC 1 button and indicator
4DISC 2 button and indicator
5DISC 3 button and indicator
6DISC SKIP/EX–CHANGE button
7§(Eject) button
8Disc tray
9EDITDIRECTION/TUNERMEMORY
button
10 PLAY MODE/DOLBY NR button
11 REPEAT/STEREO/MONO button
12 pbutton
13 ^(CD) button and indicator
14 TUNER/BAND button
15 CD NON-STOP button and indicator
16 KARAOKE PON/MPX button
17 SYNC EQ button
18 SYNC BASS button
19 REC PAUSE/START button and
indicator
20 DBFB button
21 SURROUND button
22 HI DUB button
23 CD SYNC button
24 VOLUME knob
25 PHONES jack
26 ENTER/NEXT button
27 )+ button and indicator
28 JOG/0x)dial and indicator
29 GROOVE button and indicator
30 0– button and indicator
31 AUTO BPM button and indicator
32 PAD B button and indicator
33 PAD A button and indicator
34 MIC 2 jack
35 MIC 1 jack
36 CD FLASH button
37 CD LOOP button
38 MIC LEVEL knob
39 JAM button and indicator
40 LEVEL button
41 MIX button
42 ECHO LEVEL knob
43 BEAT SPEED button
44 BEAT SELECT button
45 BEAT ON/OFF button and indicator
46 P FILE MEMORY button
47 GEQ CONTROL button
48 FILE SELECT
49 EFFECT button
50 NEXT button
51 PREV button
52 RETURN button
53 SELECT button
54 ((TAPE B) button and indicator
55 9(TAPE B) button and indicator
56 ((TAPE A) button and indicator
57 9(TAPE A) button and indicator
58 FUNCTION button
59 Remote sensor
60 DISPLAY button
61 SPECTRUM ANALYZER button
62 CLOCK/TIME SET button
63 TIMER SELECT button and indicator
64 Display Window
SECTION 2
GENERAL
Front Panel
18
9
10
11
8
234 7561
12 13 14
16 1715
19
20 21
22
38
4849
50
51
52
41
42
43
4445
4647
40 39
37
53
55
56
58
60
61
54
57 59
62
31 30 29
23
24
25
3233 34
26
27
28
35
36
63
64

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This section is extracted from instruction manual.

– 7 –
SECTION 3
DISASSEMBLY
Note: Follow the disassembly procedure in the numerical order given.
3-1. LOADING PANEL
3-2. FRONT PANEL ANDVIDEO BOARD
3 Loading panel
2 Pull-out the disc tray.
1 Turn the cam to the direction
of arrow.
Claws
3 Screw
(
BVTT 3x6
)
4 Screw (BVTT 3x6)
0 Front panel
!¢ Screw (BVTP 3x8)
!∞ Video board
6 Screw (BVTP 3x10)
!£ Two screws (BVTP 3x8)
5 Screw
(BVTP3x10)
1 Screw (BVTT 3x6)
2 Screw (BVTT 3x6)
7 Flat type wire
(CN501)
8 Flat type wire
(CN304)
Lead wires
Lead wire
9 Flat type wire
(CN303)
!¡ Flat type wire
(CN501)
!™ Flat type wire
(CN503)

– 8 –
3-3. CASSETTE LID ANDTAPE MECHANISM
3-4. CD SW BOARD AND PANEL BOARD
1 Release
3 Cassette holder (R)
assembly
4 Cassette holder (L)
assembly
Portion
B
Portion B
7 Two screws
(BVTP2.6x8)
8 Three screws
(BVTP2.6x8)
9 Tape mechanism
2 Release
(Refer to order No. 1 )
Portion A
Portion A
Note for installation
5 Tension spring
6 Tension spring
4 Knob (Jog)
5 Knob (Vol)
9 Four screws
(BVTP2.6x8)
3 CD SW board
0 Five screws
(BVTP2.6x8)
!¡ Five screws
(BVTP2.6x8)
!™ Panel board
2 Three screws
(BVTP2.6x8)
8 Flat type wire
(CN601)
1 Three screws
(BVTP2.6x8)
7 Nut
6 Nut

– 9 –
3-5. DISCTRAY
(Perform after removing the front panel.) Note:When installing the Disc tray, pull around the flat type wire to
pass through the claw
A and claw B , as shown in the figure.
Claw
B
Claw A
1
Turn the cam the
direction of arrow.
2 Pull-out the disc tray.
5 Remove the disc tray.
4 Two claws
3 Flat type wire (8 core)

– 10 –
SECTION 4
SERVICE MODE
MC Cold Reset
• The cold reset clears all data including preset data stored in the RAM to initial conditions. Execute this mode when returning the set to the
customer.
Procedure:
1. Press three buttons p, ENTER/NEXT , and 1/usimultaneously.
2. “COLD RESET” is displayed on the fluorescent display tube and reset is executed.
CD Delivery Mode
• This mode moves the optical pick-up to the position durable to vibration. Use this mode when returning the set to the customer after repair.
Procedure:
1. Press 1/ubutton to turn the set ON.
2. Press LOOP button and 1/ubutton simultaneously.
3. A message “LOCK” is displayed on the fluorescent indicator tube, and the CD delivery mode is set.
MC Hot Reset
• This mode resets the set with the preset data kept stored in the memory. The hot reset mode functions same as if the power cord is plugged
in and out.
Procedure:
1. Press three buttons p, ENTER/NEXT , and DISC 1 simultaneously.
2. The fluorescent indicator tube becomes blank instantaneously, and the set is reset.
Sled Servo Mode
• This mode can run the CD sled motor freely. Use this mode, for instance, when cleaning the pick-up.
Procedure:
1. Press 1/ubutton to turn the set ON.
2. Press three buttons p, ENTER/NEXT , and §simultaneously.
3. The Sled Servo mode is selected, if “CD” is blanking on the fluorescent indicator tube.
4. With the CD in stop status,When the )+ button is pressed the optical pick-up moves outside.When – 0button is pressed , it moves
inside.
5. To exit from this mode, perform as follows:
1) Move the optical pick-up to the most inside track.
2) Execute MC cold reset. (Press the three buttons p, ENTER/NEXT , and 1/ubutton simultaneously.)
Note:
• Always move the optical pick-up to most inside track when exiting from this mode. Otherwise, a disc will not be unloaded.
• Do not run the sled motor excessively, otherwise the gear can be chipped.
Change-over of AMTuner Step between 9kHz and 10kHz
• A step of AM channels can be changed over between 9kHz and 10kHz.
Procedure:
1. Press 1/ubutton to turn the set ON.
2. Select the function “TUNER”, and press TUNER/BAND button to select the BAND “AM”.
3. Press 1/ubutton to turn the set OFF.
4. Press ENTER/NEXT and 1/ubuttons simultaneously, and the display of fluorescent indicator tube changes to “AM 9k STEP” or “AM
10k STEP”, and thus the channel step is changed over.
LED and Fluorescent IndicatorTube All Lit, Key Check Mode
Procedure:
1. Press three buttons p, ENTER/NEXT , and DISC 2 simultaneously.
2. LEDs and fluorescent indicator tube are all turned on.
Press DISC 2 button, and the key check mode is activated.
3. In the key check mode, the fluorescent indicator tube displays “K 0V0 J0”. Each time a button is pressed, “K”value increases. However,
once a button is pressed, it is no longer taken into account.
“J”Value increases like 1, 2, 3 ... if rotating 0AMS )knob in “+” direction, or it decreases like 0, 9, 8 ... if rotating in “-” direction.
“V” Value increases like 1, 2, 3 ... if rotating VOLUME knob in “+” direction, or it decreases like 0, 9, 8 ... if rotating in “-” direction.
4. To exit from this mode, press three buttons in the same manner as step 1, or disconnect the power cord.

– 11 –
AMSTest Mode
• This mode is used for checking the AMS operations of the tape deck.
JIG
7-819-039-12 Alignment tape, AMS-110A
Procedure:
1. Press the 1/ubutton to turn the unit ON.
2. Set the tape (AMS-110A).
3. Press the three buttons p, ENTER/NEXT , and DISC 3 button simultaneously.
4. “TEST MODE” is displayed on the fluorescent display tube.
5. Press the FUNCTION button and switch the function to the deck with the tape (AMS-110A).
6. Press the CD SYNC button. “AMS CHECK” is displayed on the fluorescent display tube and the tape is rewound.
7. AMS starts in the normal direction. If the AMS count is 2 at shut down, proceed to step 8.
“NG” is displayed at other times, and the deck stops.
8. AMS starts in the opposite direction. If the AMS count is 2 at shut down again, “OK” is displayed.
“NG” is displayed at other times.
Note:The pbutton of CD section will become effective and the aging of CD section will stop sometime, if the buttons described in step 3
are not pressed simultaneously. In that case, press ^button and operate the CD section.

– 12 –
SECTION 5
TEST MODE
VIDEO CD COLOR-BARS MODE
On this mode, the data of the color-bars signal as a picture signal and the 1kHz sine wave signal as a sound signal are output by the
mechanism control microcomputer (IC502) for video CD signal check. When measurement of the voltage and waveform on the VIDEO
board, perform it in this mode.
For refernce, the color-bars signal can be observed at J302 (VIDEO OUT) and the sound signal can be observed at J101 (VIDEO/MD
(AUDIO) OUT) using an oscilloscope.
1. Connect the lead wire to both ends of the land of SL503 of the VIDEO board.
2. Turn the power on. Press FUNCTION button to select CD.
3. After 2 or 3 seconds later, connect the lead wire.
4. After measuring, remove the lead wire connected.
[VIDEO BOARD] (SIDE A)
[VIDEO BOARD] (SIDE B)
SL501
D502
SL502
IC507
IC505
CT503
SL503
TEST MODE
VIDEO
FREQUENCY
SL501
IC502
SL502
SL503
TEST
MODE

– 13 –
Precaution
1. Clean the following parts with a denatured alcohol-moistened
swab:
record/playback heads pinch rollers
erase head rubber belts
capstan idlers
2. Demagnetize the record/playback head with a head demagne-
tizer.
3. Do not use a magnetized screwdriver for the adjustments.
4. After the adjustments, apply suitable locking compound to the
parts adjusted.
5. The adjustments should be performed with the rated power sup-
ply voltage unless otherwise noted.
Torque Measurement
31 to 71 g • cm
(0.43 – 0.98 oz • inch)
2 to 6 g • cm
(0.02 – 0.08 oz • inch)
31 to 71 g • cm
(0.43 – 0.98 oz • inch)
2 to 6 g • cm
(0.02 – 0.08 oz • inch)
71 to 143 g • cm
(0.98 – 1.99 oz • inch)
100 g or more
(3.53 oz or more)
100 g or more
(3.53 oz or more)
Record/Playback Head Azimuth Adjustment
(Deck A, Deck B)
Note: Perform this adjustments for both decks.
Procedure:
1. Mode : Playback
Signal Used forTape
SECTION 6
MECHANICAL ADJUSTMENTS
Mode
FWD
Torque meter
CQ-102C
Meter reading
FWD
back tension
REV
REV
back tension
FF/REW
FWD tension
REV tension
CQ-102C
CQ-102RC
CQ-102RC
CQ-201B
CQ-403A
CQ-403R
SECTION 7
ELECTRICAL ADJUSTMENTS
DECK SECTION 0 dB=0.775V
1. Demagnetizetherecord/playbackheadwitha head damagnetizer.
2. Do not use a magnetized screwdriver for the adjustments.
3. After the adjustments, apply suitable locking compound to the
parts adjusted.
4. The adjustments should be performed with the rated power sup-
ply voltage unless otherwise noted.
5. The adjustments should be performed in the order given in this
service manual. (As a general rule, playback circuit adjustment
should be completed before performing recording circuit adjust-
ment.)
6. The adjustments should be performed for both L-CH and R-CH.
7. Switches and controls should be set as follows unless otherwise
specified.
P-4-A100
WS-48B
P-4-L300
10 kHz, –10 dB
3 kHz, 0 dB
315 Hz, 0 dB
Azimuth Adjustment
Tape Speed Adjustment
Level Adjustment
2. Turn the adjustment screw and check output peaks. If the peaks
do not match for L-CH and R-CH, turn the adjustment screw so
that outputs match within 1 dB of peak.
test tape
P-4-A100
(10kHz, –10dB) MD OUT level meter
set +
–
L-CH
peak
R-CH
peak
screw
position
output
level within
1 dB
L-CH
peak R-CH peak
screw
position
within 1dB

– 14 –
4. After the adjustments, apply suitable locking compound to the
parts adjusted.
Adjustment Location: Playback Head (Deck A)
Record/Playback/Erase Head (Deck B)
3. Mode: Playback Tape Speed Adjustment (Deck A)
Note: Set the test mode using the following method and begin tape
speed adjustment.
In the test mode, the speed will switch to double speed or
normal speed each time the HI DUB button is pressed.
Procedure:
With the power turned ON, press the pbutton, ENTER/NEXT
button, and DISC 3 button simultaneously.
(The “CD TYPE INDICATOR” on the fluorescent display tube will
blink while in the test mode.)
To exit the test mode, press the 1/u button.
1. Insert the WS-48B into deck B.
2. Press the (button of deck B.
3. Press the HI DUB button and play the tape at double speed.
4. Adjust RV1001 of the LEAF SW board so that the reading of
the frequency counter becomes 6000 ± 180 Hz.
5. Press the HI DUB button and play the tape at normal speed.
6. Adjust RV1002 of the LEAF SW board so that the reading of
the frequency counter becomes 3000 ± 90 Hz.
Adjustment Location: LEAF SW board
SampleValue of Wow and flutter
W.RMS (JIS) less than 0.3%
(test tape: WS-48B)
Playback Level Adjustment (Deck A, Deck B)
Procedure:
Mode: Playback
Deck A is RV311 (L-CH) and RV411 (R-CH), deck B is RV301
(L-CH) and RV401 (R-CH)
so that adjustment within the following adjustment level.
Adjustment level:
CN301 playback level: 301.5 to 338.3 mV (–8.2 to –7.2 dB)
level difference between the channels: within ± 0.5 dB
Adjustment Location:AUDIO board
Adjustment Location
[LEAF SW BOARD]
test tape
P-4-A100
(10kHz, –10dB) oscilloscope
set
Waveform of oscilloscope
in phase 45
°
90 °
135 °
180 °
good wrong
MD OUT
Reverse Foward
test tape
P-4-L300
(315Hz, 0dB) level meter
set
MD OUT
RV1002 RV1001
RV1002(Normal Speed
)
RV1001(High Speed)

– 15 –
Record Bias Adjustment (Deck B)
Procedure:
INTRODUCTION
When set to the test mode performed in Tape Speed Adjust-
ment,when the tape is rewound after recording, the “REC memory
mode” which rewinds only the recorded portion and playback is
set.
This “REC memory mode” is convenient for performing this ad-
justment. During recording, the input signal FUNCTION will auto-
matically switch to VIDEO.
(After recording, press the – 0button without stopping will
return to the position where recording was started.)
1. Press FUNCTION button to select VIDEO. (This step is not
necessary if the above test mode has already been set.)
2. Insert a tape into deck B, press the rREC button, and then
press the (button to start recording.
3. Mode: Record
5. Confirm playback the signal recorded in step 2 become adjust-
ment level as follows.
If these levels do not adjustment level, adjust the RV341 (L-CH)
and RV441 (R-CH) on theAUDIO board to repeat steps 3 and 4.
Adjustment level: The playback output of 10 kHz level difference
against 315 Hz reference should be ± 1.0 dB.
Adjustment Location:AUDIO board
Record Level Adjustment (Deck B)
Procedure:
INTRODUCTION
When set to the test mode performed in Tape Speed Adjust-
ment, when the tape is rewound after recording, the “REC memory
mode” which rewinds only the recorded portion and playback is
set.
This “REC memory mode” is convenient for performing this
adjustment. During recording, the input signal FUNCTION will au-
tomatically switch to VIDEO.
(After recording, press the – 0button without stopping will
return to the position where recording was started.)
1. Press FUNCTION button to select VIDEO 1. (This step is not
necessary if the above test mode has already been set.)
2. Insert a tape into deck B, press the rREC button, and then
press the (button to start recording.
3. Mode: Record
4. Mode: Playback
5. Confirm playback the signal recorded in step 2 become adjust-
ment level as follows.
If these levels do not adjustment level, adjust the RV301 (L-CH)
and RV351 (R-CH) on the MAIN board to repeat steps 3 and 4.
Adjustment level:
CN403 playback level: 47.2 to 53.0 mV (–24.3 to –23.3 dB)
Adjustment Location: MAIN board
Adjustment Location:
[AUDIO BOARD] (Conductor Side)
4. Mode: Playback
[MAIN BOARD] (Conductor Side)
recorded
position level meter
set
MD OUT
AF OSC
VIDEO (AUDIO) IN
1) 315 Hz
2) 10 kHz
blank tape
CS-123
set
attenuator 600
Ω
} 50 mV (–23.8 dB)
AF OSC
VIDEO (AUDIO) IN
315Hz 50 mV (–23.8 dB)
blank tape
CS-123
set
attenuator 600
Ω
recorded
position level meter
set
MD OUT
RV441 RV341
RV301(Lch),RV401(Rch)
Playback Level (Deck B)
RV301 RV401
RV341(Lch),RV441(Rch)
Record Bias RV311(Lch),RV411(Rch)
Playback Level (Deck A)
RV311 RV411
IC301
Record Level (L CH)
RV301
CN303 RV351
Record Level (R CH)
56
43 42 29
28
15
14
1

– 16 –
CD SECTION
Note:
1. CD Block is basically constructed to operate without adjustment.
Therefore, check each item in order given.
2. UseYEDS-18 disc (3-702-101-01) unless otherwise indicated.
3. Use an oscilloscope with more than 10MΩimpedance.
4. Clean the objectlensbyanapplicatorwithneutraldetergent when
the signal level is low than specified value with the following
checks.
S Curve Check
Adjustment Location: BD board
Procedure :
1. Connect the oscilloscope to test points TP (FE) and TP (VC).
2. Connect TP (FEI) and GND, and TP (AGCCON) and GND of
the BD board with lead wires.
3. Press the 1/ubutton to turn the set ON.
4. With the disc (YEDS-18) loaded, press the ^button and
perform focus search. (Focus search will be performed in the
same way even while the disc table is pushed in and out.)
5. Check the symmetry and peak to peak level of the oscilloscope
waveform (S curve) at this time.
S-curve waveform
6. After check, remove the lead wire connected in step 2.
Note: • Try to measure several times to make sure than the ratio of
A : B or B :A is more than 10 : 7.
• Take sweep time as long as possible and light up the bright-
ness to obtain best waveform.
Adjustment Location: BD board
RF Level Check
Procedure :
1. Connect oscilloscope to test point TP (RF) and TP (VC) on BD
board.
2. Connect TP (AGCCON) and GND of the BD board with lead
wires.
3. Press the 1/ubutton to turn the set ON.
4. Put disc (YEDS-18) in and playback 5track.
5. Confirm that oscilloscope waveform is clear and check RF sig-
nal level is correct or not.
6. After check, remove the lead wire connected in step 2.
oscilloscope
BD board
TP (FE)
TP (VC) +
–
oscilloscope
BD board
TP (RF)
TP (VC) +
–
E-F Balance (Traverse) Check
oscilloscope
BD board
TP (TE)
TP (VC) +
–
Adjustment Location: BD board
Procedure :
1. Connect oscilloscpe to test point TP (TE) on BD board.
2. Short-circuit SL502 of the video board to GND.
3. Turned Power switch on. Press FUNCTION button to select
CD.
4. Put disc (YEDS-18) in to play the number five track.
5. Press the PLAY MODE/DOLBY NR button. (The tracking
servo and the sledding servo are turned OFF.)
6. Check the level B of the oscilliscope's waveform and theA (DC
voltage) of the center of the Traverse waveform.
Confirm the following :
A/B x 100 = less than ± 22%
Traverse waveform
0V
level : 1.3 ± 0.6 Vp-p
A (DC voltage)
Center of the waveform
B
7. Press the PLAY MODE/DOLBY NR button. (The tracking
servo and sledding servo are turned ON.) Confirm the C (DC
voltage) is almost equal to theA (DC voltage) is step 7.
Traverse waveform
0V C (DC
voltage)
Tracking servo
Sled servo
OFF
Tracking servo
Sled servo
ON
symmetry
A
B
Within 4.0
± 1.0 Vp-p
Note: Clear RF signal waveform means that the shape “◊” can be
clearly distinguished at the center of the waveform.
RF signal waveform
VOLT/DIV : 200mV
TIME/DIV : 500ns
level : 1.75 ± 0.25 Vp-p
8. Desolder the short-land (SL502) short-circuited at step 2.
Adjustment Location: BD board

– 17 –
VIDEO SECTION
Frequency adjustment
1. Connect the frequency counter to check point of the VIDEO
board.
2. Adjust CT503 of theVIDEO board so that the frequency counter
read 27MHz ± 80Hz at STOP condition.
[ VIDEO BOARD ] – SIDE B –
Adjustment Location :
[ VIDEO BOARD ] – SIDE A –
frequency counter
VIDEO board
(29 MHz) +
–
SL501 IC502
IC506
(27MHz)
(GND)
SL502
SL503
TEST
MODE
SL501
D502 SL502
CT503
SL503
TEST MODE
VIDEO
FREQUENCY
(27MHz)
(GND)
IC507
IC505
Adjustment Location :
[ BD BOARD ] — SIDE B —
TP
(VC)
TP
(RF)
TP
(TE)
TP
(IOP)
TP
(FE)
TP
(AGCCON)

– 18 –
SECTION 8
DIAGRAMS
8-1. CIRCUIT BOARDS LOCATION
ENCAPSULATED COMPONENT/TUNER
unit is supplied as the assembled block.
MAIN board
PANEL board
CD SW board
SURROUND board
ENCAPSULATED COMPONENT
(EXCEPT THAI)
TUNER unit
(THAI)
TRANS board
VIDEO board
SENSOR board
CONNECTOR board
BD board
MOTOR (SLIDE) board
MOTOR (TURN) board
AUDIO board
LEAF SW board

HCD-VX8/VX8J
– 19 – – 20 –
8-2. BLOCK DIAGRAMS
– CD SECTION –
E
F
A
B
C
D
DRIVE
Q101
LD
RF EQ
AMP
SUMMING
AMP
RF
ERROR
AMP
FOCUS
ERROR
AMP
TRACKING
APC LD
AMP
VC
BUFFER
VC
REF
RF AMP
IC103
DIGITAL SERVO
DIGITAL SIGNAL PRCESSOR
IC101
IC381
LASER
DIODE
DETECTOR
OPTICAL PICK-UP BLOCK
(D/Q-Np)
A
C
D
B
E
F
LD
POWER
PD
LD
PD
LD
A
C
D
B
E
F
TE
FE
RFD
RFI
ASYMMETRY
CORRECTION
AUTO
SEQUENCER
SERVO
INTEG-
RATOR
DIGITAL
PLL
EFM
DEMODULATOR
REGISTER
SUB CODE
PROCESSOR
ERROR
CORRECTOR
DATA BUS
32K
RAM
D/A
INTERFACE
DIGITAL
CD DIGITAL
OUT
OPTICAL
OUT DOUT
SERVO
INTERFACE
DIGITAL
CLV
LD ON
OP AMP
ANALOG SW
A/D
CONVERTER
PWM
GENERATOR
TRACKING
PWM
GENERATOR
FOCUS
PWM
GENERATOR
SLED
PWM
GENERATOR
VC
TRACKING
SERVO
FOCUS
SERVO
SLED
SERVO
SERVO DSP
TFDR
TRDR
FFDR
FRDR
SFDR
SRDR
MDP
DETECTOR
MIRR
DFCT
FOK
D OUT
PCM-D
S STOP
RFDC
FE
TE
CE
VC
SE
CPU
INTERFACE
SENS
DATA
XLAT
CLOK
CLOCK
GENERATOR
XTAI
XTSL
M
M
TRACKING
COIL
FOCUS
COIL
SLED
MOTOR
M102
SPINDLE
MOTOR
M101
T+
T
F+
F
SD+
SD
SP+
SP
FOCUS/TRACKING COIL DRIVE
SPINDLE/SLED MOTOR DRIVE
IC102
VC
TFDR
TRDR
FFDR
FRDR
SFDR
SRDR
XRST
MUTE
09
S101
LIMIT SW
SQCK
A+5V
IC104
XRST
ADATA
BCLK
LRCK
MCK
SENS
CTRL1
DATA
SCLK SCLK
XLT
CLK
SCOR
SQSO
SCOR
SUBQ
SQCK
LPH
XRST
LD ON
LRCK
BCLK
C2PO
MUTE
MUTE
C2PO
D+5V
MD2
RF AC
ASYI
ASYO
CONTROL SIGNAL
BLOCK
SERVO
BLOCK
VCC
VC
VIDEO
SECTION
• SIGNAL PATH
: CD
: Digital out
: VIDEO
(Page 21)
MAIN
SECTION
(Page 25
M
TABLE
SENSOR
IC702
T. SENS
OPEN
S801
OPEN/CLOSE
DET
OUT1 IN1
IN2
OUT2
M
M701
TURN
MOTOR
TBL.L
TBL.R
TURN
MOTOR DRIVER
IC701
DISC
SENSOR
IC703
ROTARY
ENCODER
S811
Q701
DISC SENS
ENC 1
ENC 2
ENC 3
M801
SLIDE
MOTOR
OUT2
OUT1
RIN
FIN
SLIDE
MOTOR DRIVER
IC801
LOAD IN
LOAD OUT
A
C
(XTAL 33.8MHz)
42
5
7
8
6
11
10
3
4
23
24
27
25
20
22
21
12
13
17
14
16 50
48
49
43
38
41
39
40
42
32
31
34
33
30
29
25
64
63
67
66
14
65
71
3
7
69
15
6
5
4
77
76
8
26
8
8
82
8
8
8
8
8
8
1
12
11
14
13
17
18
15
16
3
2
6
5
INTEG-
RATOR

HCD-VX8/VX8J
– VIDEO SECTION –
– 21 – – 22 –
SYSTEM
SELECT
S501
65
15
13
09
29
I
2
C.CLK
30
I
2
C.DATA
I
2
C.CLK
I
2
C.DATA
I to U
U to I
TXD
RXD
72
U to I
DSENS
XRESET
TEST LED
NT/PAL
XOUT
+5V
D502
A7
DF LATCH
SHARPNESS
XIN
24
45 BUS
DSP DATA
DSP LATCH
SENSE CLK
DSP CLK
SENSE
DSP MUTE
CTRL1(L:DOUBLE)
CTRL2
LDON
SCOR
SUBQ DATA
22
34
X501
NTSC
AUTO
PAL
10MHz
X503
27MHz
19
20
X401
8MHz
MECHA. CONTROL
IC502
INTERFACE
IC402
LEVEL SHIFT
IC504
LEVEL SHIFT
IC501
D-RAM
IC507
ROM
IC506
AMP
IC101
OUTPUT AMP
IC401
VIDEO/CD DECODER
IC505
DIGITAL FILTER & D/A CONVERTER
IC509
DATA1O
DATA1I
CLK1
CL680 INT
CL680 HSEL
CL680 HRDY
680 RESET
DATA0
DATAI
CLK1
INT
HSEL
HRDY
RESET
ADATA
BCLK
LRCK
C2P0
DATA
XLT
CLK
SENS
SCLK
MUTE
CTRL1
LDON
SCOR
SUBQ
SQCK
XRST
MCK
A
CD
SECTION
(Page 20)
11
12
10
13
9
• R CH: Same as L ch
• SIGNAL PATH
: CD
: CHROMA
:Y
: VIDEO
SUBQ CLK
DEVICE RESET
23
19
14
RESET
XIN
XOUT
18
93
73
12
P.ON 38
3
4
5
1
2
10
11
27
28
18
37
36
77
20
21
33
32
31
69
HD-OUT
6CD-C2P0
CD-LRCK
CD-BCK
HRDY
HD-IN
HCK
HINT
HSEL
RESET
PGIO2/VSYNC/CSYNC
INVERTER
Q502
CD-DATA
MWE WE
RAS UCAS LCAS A0 A8 DQ1 DQ16
RASO
CAS
MCE
MD0
I
MD15
MA0
I
MA10
C-OUT
Y-OUT
75
DA-DATA
DA-BCK 111
VCK-IN 106
DA-XCLK 86
110
DA-LRCK 108
112
119
117
113
114
121
93
60
3
5
4
13 14 28 29
38 42 40
10
8
4
13
5
1
13
8
12
6
11
1
3
7
5
1
3
19
17
DATA0
CLK1 8
7
10 21 20 4
11
18
MODE
PLM
D/A
CONV
CLOCK
DIVIDER
9
24
1
16 - 19 22 - 26 2 - 10 31 - 39
O0 O7 A11 A17 A0 A10 CE
13 - 15 17 - 21 25 4 28 29 3 2 14 10 12 - 5 27 26 23
58 - 44
10 - 29
22
37
MUTE
Q454
BUFFER
Q301
MUTE
Q453
MIX AMP
Q308,310
BUFFER
Q303,304
TRAP
Q302,306,307
1
3
2
4
14
VIDEO OUT
J302
J301
VIDEO
FREQUENCY
CT503
–5V/IIC DATA
L - CH
R-CH
P. ON/IIC. CLK
XRST
27MHz
384FS
768FS
S VIDEO
OUT
DATAI
DATAO
CLK1
HRDY
INT
HSEL
RST
CLK1, DATA0
(XTAL 33.8MHz)
27MHz
RSTB
3.3V REG
Q531 +3.3VD5V
C
MAIN
SECTION
(Page 25)
E
MAIN
SECTION
(Page 26)