Sony HCD-VX550 Service manual

HCD-VX550

SERVICE MANUAL

HCD-VX550 is the Amplifier, Video
CD player, Tape Deck and Tuner
section in MHC-VX550.

Dolby noise reduction manufactured under license
from Dolby Laboratories Licensing Corporation.
“DOLBY” and the double-D symbol a are trade­marks of Dolby Laboratories Licensing Corporation.

CD
Section

Tape deck
Section

Chinese Model

Model Name Using Similar Mechanism NEW
CD Mechanism Type CDM38LH-5BD36L
Base Unit Name BU-26BD36L
Optical Pick-up Name KSS-213D/Q-RP
Model Name Using Similar Mechanism HTC-V5550
Tape Transport Mechanism Type TCM-230AWR2

Amplifier section

The following measured at AC 120, 220, 240 V 50/60

Hz

DIN power output (rated)110 + 110 W

(8 Ω at 1 kHz, DIN)

Continuous RMS power output (reference)

140 + 140 W
(8 Ω at 1 kHz, 10% THD)

Inputs
MD IN: voltage 450 mV,
(phono jacks) impedance 47 kΩ
VIDEO (AUDIO) IN: voltage 250 mV,
(phono jacks) impedance 47 kΩ
MIC 1/2 (phone jack): sensitivity 1 mV, impedance

10 kΩ

SPECIFICATIONS

Outputs
MD OUT (phono jacks): voltage 250 mV

impedance 1 kΩ

VIDEO OUT (phono jack):

max,output level
1Vp-p, unbalanced, Sync
negative, load impedance
75 Ω

S-VIDEO OUT (4-pin/ mini-DIN jack):

Y: 1Vp-p, unbalanced,
Sync negative,
C: 0.286Vp-p,
load impedance 75 Ω

PHONES (stereo phone jack):

accepts headphones of 8 Ω
or more

SPEAKER: accepts impedance of 8 to

16 Ω

SUPER WOOFER Voltage 1 V, impedance

kΩ

MINI Hi-Fi COMPONENT SYSTEM

SUPER VIDEO CD/VIDEO CD
/CD player section

System Compact disc and digital

Laser Semiconductor laser

Laser output Max. 44.6 µW*

Frequency response 2 Hz - 20 kHz (±0.5 dB)
Wavelength 780 -790 nm
Signal-to-noise ratio More than 90 dB
Dynamic range More than 90 dB

1

Video color system format

audio and video system
(λ=780nm)

Emission duration:
continuous

*This output is the value
measured at distance of 200
mm from the objective lens
surface on the Optical Pick-up
Block with 7 mm aperture.

NTSC, PAL

Continued on next page

MICROFILM

CD OPTICAL DIGITAL OUT
(Square optical connector jack, rear panel)
Wavelength 660 nm
Output Level –18 dBm

TABLE OF CONTENTS

1. SERVICING NOTES·················································3

Tape player section

Recording system 4-track 2-channel stereo
Frequency response 40 - 13,000 Hz (±3 dB),
(DOLBY NR OFF) using Sony TYPE I cassette

40-14,000 Hz (± 3 dB),
using Sony TYPE II cassette

Tuner section

Fm stereo, FM/ AM superheterodyne tuner

FM tuner section

Tuning range 87.5-108.0 MHz
Antenna FM lead antenna
Antenna terminals 75 Ω unbalanced
Intermediate frequency 10.7 MHz

AM tuner section

Tuning range
2 Band type: 531-1,602 kHz

(with the interval set at 9 kHz)
530-1,710 kHz
(with the interval set at 10 kHz)

3 Band type:
MW: 531-1,602 kHz

(with the interval set at 9 kHz)
530-1,710 kHz
(with the interval set at 10 kHz)

SW: 5.95-17.90 MHz

(with the interval set at 5 kHz)
Antenna AM loop antenna
Antenna terminals External antenna terminal
Intermediate frequency 450 kHz

General

Power requirements 220 V AC, 50/ 60 Hz
Power consumption: 160 W
Dimensions (w/h/d) Approx. 280 × 340 × 395 mm
Mass: Approx. 10.0 kg

Design and specifications are subject to change without notice.

2. GENERAL .......................................................................... 5

3. DISASSEMBLY ................................................................ 8

4. TEST MODE................................................................... 11

5. MECHANICAL ADJUSTMENTS ............................ 14

6. ELECTRICAL ADJUSTMENTS

DECK Section .................................................................. 14

CD Section ....................................................................... 17

VIDEO Section.................................................................17

7. DIAGRAMS

7-1. Block Diagram

CD SERVO Section.......................................................... 18

AUDIO/VIDEO CD Section ............................................ 19

TAPE DECK Section ....................................................... 20

MAIN Section .................................................................. 21

DISPLAY/KEY CONTROL/

POWER SUPPLY Section················································22
7-2. Circuit Board Location ····················································· 23

7-3. Printed Wiring Board BD Board .................................... 24

7-4. Schematic Diagram BD Board ....................................... 25

7-5. Schematic Diagram VIDEO Board (1/2)........................26

7-6. Schematic Diagram VIDEO Board (2/2)........................27

7-7. Printed Wiring Board VIDEO Board..............................28

7-8. Printed Wiring Boards CD MOTOR Section ................. 30

7-9. Schematic Diagram CD MOTOR Section......................31

7-10. Printed Wiring Board AUDIO Board ............................. 32

7-11. Schematic Diagram AUDIO Board ................................ 33

7-12. Printed Wiring Board LEAF SW Board.........................34

7-13. Schematic Diagram LEAF SW Board............................34

7-14. Printed Wiring Board MAIN Board ............................... 35

7-15. Schematic Diagram MAIN Board (1/4) ......................... 36

7-16. Schematic Diagram MAIN Board (2/4) ......................... 37

7-17. Schematic Diagram MAIN Board (3/4) ......................... 38

7-18. Schematic Diagram MAIN Board (4/4) ......................... 39

7-19. Printed Wiring Board PANEL Board ............................. 40

7-20. Schematic Diagram PANEL Board ................................ 41

7-21. Printed Wiring Board CD SW/5V POWER Board ........ 42

7-22. Schematic Diagram CD SW/5V POWER Board ........... 42

7-23. Printed Wiring Board TRANSFORMER Board ............ 43

7-24. Schematic Diagram TRANSFORMER Board ............... 43

7-25. Printed Wiring Board SURROUND Board .................... 44

7-26. Schematic Diagram SURROUND Board....................... 44

7-27. IC Block Diagrams ........................................................... 45

7-28. IC Pin Function Description............................................. 49

8. EXPLODED VIEWS ..................................................... 60

9. ELECTRICAL PARTS LIST..................................... 68

2

SECTION 1

3

SERVICING NOTES

SELF-DIAGNOSIS

This unit is equipped with a self-diagnosis function.
The function is used for diagnosing the conditions of the circuits of
the VIDEO board.
The circuits can be determined if normal or abnormal by the lighting
of D502 of the VIDEO board.

Lighting of D502

When lit : Operates normally
Blinks repeatedly : The circuit may be faulty.

VIDEO Board (SIDE B)

CN501

100

31

30

1

NOTES ON HANDLING THE 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 pick­up block. Therefore, when checking the laser diode emission,
observe from more than 30 cm away from the objective lens.

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.

IC505

50

51 80

CN502

D502

81

SL501

SL502

SL50

CAUTION

Use of controls or adjustments or performance of procedures
other than those specified herein may result in hazardous
radiation exposure.

This appliance is classified as a CLASS 1 LASER product.
The CLASS 1 LASER PRODUCT MARKING is located on
the rear exterior.

Laser component in this product is capable of emitting radiation
exceeding the limit for Class 1.

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 .

3

HOW TO OPEN THE DISC TRAY WHEN POWER SWITCH TURNS’ OFF.

e

1

Remove the Case.

3

Pull-out the disc tray.

2

Turn the cam to the
direction of arrow.

NOTE FOR INSTALLATION (ROTARY ENCODER)

BU cam

Groove

Note:When attaching the Base unit, Insert th
section A into the groove of BU cam.

Section A

Note:When attaching the BU cam,
engage the Rotary encoder
switch as shown in the figure.

4

• LOCATION OF CONTENTS

Front View

SECTION 2

GENERAL

qs08642

13 5 7 9 qa

qd

ef
ed

es

ea
e;
wl
wk

1 1/u button
2 9 TAPE A button and indicator
3 (STANDBY) DEMO button
4 ( TAPE A button and indicator
5 DISC 1 button
6 9 TAPE B button and indicator
7 DISC 2 button
8 ( TAPE B button and indicator
9 DISC 3 button
0 p button
qa DISC SKIP, EX-CHANGE button
qs ^ CD button and indicator
qd § button
qf SVCD/VCD indicator
qg PBC indicator
qh PBC OFF indicator
qj TUNER/BAND button

qf

qg

qh

qj

qk
ql
w;
wa

wswdwfwgwhwj

qk REC PAUSE/START button and indicator
ql HI-DUB button
w; CD SYNC button
wa PHONE jack
ws VOLUME knob
wd + ) button and indicator
wf JOG dial and indicator
wg – 0 button and indicator
wh CD FLASH button
wj CD LOOP button
wk MIC 2 jack
wl MIC 1 jack
e; MIC LEVEL knob
ea ECHO LEVEL knob
es FUNCTION button
ed SYNC EQ indicator
ef EFFECT indicator

5

eg eh ej ek el r; ra rs rd rf

rg
rh

rj

rk

rlt;tatstdtftgth

eg EDIT/DIRECTION

TUNER MEMORY button

eh PLAY MODE, DOLBY NR button
ej REPEAT STEREO/MONO button
ek FILE SELECT button
el SELECT button
r; RETURN button
ra PREV button
rs NEXT button
rd CD NON-STOP button and indicator
rf KARAOKE PON/MPX button
rg SYNC BASS H indicator

rh SYNC BASS L indicator
rj SYNC EQ button
rk SYNC BASS button
rl CINEMA SPACE/SURROUND button
t; DBFB button
ta ENTER/NEXT button and indicator
ts GROOVE button and indicator
td SPECTRUM ANALYZER button
tf TIMER SELECT button and indicator
tg CLOCK/TIMER SET button
th DISPLAY button

6

This section is extracted
from instruction manual.

7

SECTION 3

DISASSEMBLY

Note : Follow the disassembly procedure in the numerical order given.

3-1. COVER

6

cover

2

screw

3

two screws
(case 3TP2) (3

(case 3TP2) (3

×

8)

×

12)

5

4

4

1

three screws
(BVTP3

2

screw
(case 3TP2) (3

3

two screws
(case 3TP2) (3

×

8)

×

12)

×

8)

3-2. LOADING PANEL ASS’Y

A

1

Turn the cam-in the
direction of the arrow

A

2

Pull-out
the disc tray.

3

loading panel ass’y

.

8

3-3. FRONT PANEL SECTION

)

4

screw
(BVTT3

×

10)

6

front panel section

1

wire (flat type)
(15 core) (32 cm) (CN303)

2

screw
(BVTT3

×

6)

3

two lugs

4

screw
(BVTP3

×

10)

3

lug

2

1

wire (flat type)
(23 core) (23 cm) (CN501)

screw
(BVTT3

×

6

1

wire (flat type) (17 core)

5

two screws
(BVTT3

×

6)

(CN304)

3-4. VIDEO BOARD, CD MECHANISM DECK SECTION (CDM38LH-5BD36L)

8

Remove the CD mechanism
deck (CDM38LH-5BD36L)
in the direction of arrows

A

– B.

6

screw
(BVTP3

×

10)

B

A

wire (flat type)

1

(15 core) (17 cm) (CN502)

2

two screws

×

(BVTP3

8)

7

two screws
(BVTP3

×

5

8)

2

screw
(BVTP3

chassis

×

8)

3

VIDEO
board

1

wire (flat type)
(25 core) (18 cm)
(CN501)

4

screw
(BVTP3

×

8)

6

screw
(BVTP3

9

two connectors
(CN392, 393)

×

10)

9

3-5. TAPE MECHANISM DECK SECTION (TCM-230AWR2)

)

2

Open two
cassette lids.

1

Push the cassette lid.

3

three screws
(BVTP2.6

×

8)

3

two screws
(BVTP2.6

4

tape mechanism deck section
(TCM-230AWR2)

×

8)

3-6. MAIN BOARD

2

connector
(CN952)

1

Push the cassette lid.

2

connector
(CN953)

3

two screws
(BVTP3 × 8)

1

wire (flat type)
(15 core)(15 cm)(CN371)

5

five screws
(BVTP3 × 8

10

6

Remove the MAIN board
in the direction of the arrow.

4

two screws
(BVTP3 × 8)

7

connector
(CN403)

SECTION 4

TEST 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. Turn the power ON or set to the DEMO mode.

2. Press three buttons of p , ENTER/NEXT , and 1 /u

simultaneously.

3. The set is reset, and displays “COLD RESET”, then becomes

DEMO mode.

[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. Turn the power ON or set to the DEMO mode.

2. Press three buttons of p , ENTER/NEXT , and DISC1

simultaneously.

3. The set is reset, and becomes standby state.

[Change-over the AM Tuning Interval]
(EXCEPT Saudi Arabia model)

• The AM tuning interval can be changed over 9 kHz or 10 kHz.

Procedure:

1. Press the 1/u button to turn the power ON.

2. Select the function “TUNER”, and press the TUNER/BAND

button to select the BAND “AM (MW)”.

3. Press the 1/u button to turn the power OFF.

4. Press the ENTER/NEXT and 1/u buttons simultaneously, and

the display on the fluorescent indicator tube changes to “ AM 9
k STEP” or “AM 10 k STEP”, and thus the tuning interval is
changed over.

[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 the 1/u button to turn the power ON.

2. Press the CD LOOP and 1/u buttons simultaneously.

3. A message “LOCK” is displayed on the fluorescent indicator

tube, and the CD delivery mode is set.

[LED and Fluorescent Indicator Tube All Lit, Key Check
Mode]

Procedure:

1. Press three buttons of p , ENTER/NEXT , and DISC1

simultaneously.

2. LEDs and fluorescent indicator tube are all turned on.

Press the DISC1 button, and the key check mode is activated.

3. In the key check mode, the fluorescent indicator tube displays

“K 0 J0 V0”. 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 turn the JOG dial clockwise,
or it decreases like 0, 9, 8 ... if turn the JOG dial
counterclockwise.
“V” value increases like 1, 2, 3 ... if turn the VOLUME dial
clockwise, or it decreases like 0, 9, 8 ... if turn the JOG dial
counterclockwise.

4. To exit from this mode, press three buttons in the same manner

as step 1, or disconnect the power cord.

11

[Aging Mode]

This mode can be used for operation check of tape deck section.
Tape deck section work in parallel.

• If an error occurred:
The aging operation stops and display then status.

• If no error occurs:
The aging operation continues repeatedly.

Procedure:

1. Load the tapes into the decks A and B respectively.

2. Press the FUNCTION button to select the function “CD”.

3. Press the PLAY MODE button to set the “ ALL DISCS” mode,

and press the REPEAT button to “REPEAT” off.

4. Press three buttons of p , ENTER/NEXT , and DISC SKIP/

EX-CHANGE simultaneously.

5. The aging mode is activated, if the indicator of disc tray number

on the fluorescent indicator tube is blinking.

6. To exit from the aging mode, press the 1/u button to turn the

power OFF and operate the cold reset. (Refer to the “MC Cold
Reset”)

1. Display at the Aging Mode

• Display operating state of tape deck section alternately.

• If an error occurred, stop display.

2. Tape Deck Section

• The sequence during the aging mode is following as below.

• If an error occurred, stop display that step.

Aging mode sequence (Tape deck section) :

Rewind the tape A and B

“TAPE A AG-1”

Shut off

FWD play the tape A

“TAPE A AG-2”

2 minutes

Fast forward the tape A

“TAPE A AG-3”

Shut off or 20 seconds

REV play the tape A

“TAPE A AG-4”

2 minutes

Rewind the tape A

“TAPE A AG-5”

Shut off

FWD play the tape B

“TAPE B AG-2”

2 minutes

Fast forward the tape B

“TAPE B AG-3”

Shut off or 20 seconds

REV play the tape B

“TAPE A AG-4”

2 minutes

Rewind the tape B

“TAPE B AG-5”

Shut off

Note: “TAPE * AG-*” is display of each step.

12

[VIDEO CD Color-bars Mode]

On this mode, the data of the color-bars signal as a picture signal
and the 1 kHz sine wave signal as a sound signal are output by the
mechanism controller (IC505) for the video CD signal check. When
measurement of the voltage and waveform on the VIDEO board,
perform it in this mode.
For reference, the color-bars signal can be observed at J502 (VIDEO
OUT) and the sound signal can be observed at J101 (VIDEO/MD
(AUDIO) OUT) using an oscilloscope.

Procedure:

1. Short the both ends of the land of SL503 of the VIDEO board.

2. Turn the power on. Press the FUNCTION button to select CD.

3. The color-bars appears when the CD is in stop status, and it
disappears when the CD goes in play status.

4. After measuring, remove the lead wire connected.

VIDEO board (SIDE B)

3150

30

1

10081

CN501

CN502

SL503

51

IC505

80

SL501

SL502

13

SECTION 5

r

MECHANICAL ADJUSTMENTS

SECTION 6

ELECTRICAL ADJUSTMENTS

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
demagnetizer.

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
supply voltage unless otherwise noted.

Torque Measurement

Mode

FWD
FWD

back tension
REV
REV

back tension
FF/REW

FWD tension

REV tension

Torque meter

CQ-102C

CQ-102C

CQ-102RC

CQ-102RC

CQ-201B

CQ-403A

CQ-403R

Meter reading

31 to 71 g • cm

(0.43 - 0.98 oz • inch)

2 to 6 g • cm

(0.03 - 0.08 oz • inch)

31 to 71 g • cm

(0.43 - 0.98 oz • inch)

2 to 6 g • cm

(0.03 - 0.08 oz • inch)

71 to 143 g • cm

(0.99 - 1.99 oz • inch)

100 g or more

(3.53 oz or more)

100 g or more

(3.53 oz or more)

DECK SECTION

1. Demagnetize the record/playback head with a head
demagnetizer.

2. Do not use a magnetized screwdriver for the adjustments.

3. After the adjustments, apply suitable locking compound to the
parts adjust.

4. The adjustments should be performed with the rated power
supply 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
adjustment.)

6. The adjustments should be performed for both L-CH and R­CH.

7. Switches and controls should be set as follows unless otherwise
specified.

8. Set to the DOLBY NR OFF.

9. Set to the test mode.
(1) Press the 1/u button to turn the power ON.
(2) Select the function “TAPE A or B”.
(3) Press the button of p , ENTER/NEXT , and DISC3

simultaneously, to set the tape deck test mode and blink
the indicator of disc tray number on the fluorescent indicator
tube.

(4) To exit from the test mode, press the 1/u button.

• Test T ape

Tape Signal Used for

P-4-A100 10 kHz, -10 dB Azimuth Adjustment

WS-48B 3 kHz, 0 dB Tape Speed Adjustment

P-4-L300 315 Hz, 0 dB Level Adjustment

0 dB = 0.775 V

Record/Playback Head Azimuth Adjustment

DECK A DECK B

Note: Perform this adjustments for both decks

Procedure:

1. Mode: Playback (FWD)

test tape
P-4-A100
(10 kHz, – 10 dB)

MAIN board
MD OUT jack (J101)
L-CH, R-CH

level mete

set

+
–

14

2. Turn the adjustment screw and check output peaks. If the peaks

+

–

set

test tape
WS-48B
(3 kHz, 0 dB)

MAIN board
MD OUT jack (J101)
L-CH, R-CH

frequency counter

r

do not match for L-CH and R-CH, turn the adjustment screw so
that outputs match within 1dB of peak.

Tape Speed Adjustment DECK B

Mode: Playback

Output
level

within
1dB

L-CH
peak

R-CH
peak

within
1dB

Screw
position

L-CH
peak

Screw
position

R-CH
peak

3. Mode: Playback

MAIN board
test tape
P-4-A100
(10 kHz, – 10 dB)

L-CH

set

R-CH

in phase 45°90°135°180

MD OUT jack (J101)

L-CH

R-CH

waveform of oscilloscope

good

oscilloscope

wrong

H

V

°

4. Repeat step 1 to 3 in playback (REV) mode.

5. After the adjustments, apply suitable locking compound to the
pats adjusted.

1. Insert the WS-48B into the deck B.

2. Press the ( button on the deck B.

3. Press the HI-DUB button in playback mode.
Then at HIGH speed mode.

4. Adjust RV1001 on the LEAF SW board do that frequency
counter reads 6,000 ± 180 Hz.

5. Press the HI-DUB button.
Then back to NORMAL speed mode.

6. Adjust RV1002 on the LEAF SW board so that frequency
counter reads 3,000 ± 90 Hz.

Adjustment Location: LEAF SW board
Sample value of Wow and Flutter: 0.3% or less W.RMS (JIS)

(WS-48B)

Playback level Adjustment DECK A DECK B

Procedure:

Mode: Playback

test tape
P-4-L300
(315 Hz, 0 dB)

set

MAIN board
MD OUT jack (J101)
L-CH, R-CH

level mete

+
–

Adjustment Location: Playback Head (Deck A).

Record/Playback/Erase Head (Deck B).

forward

reverse

Deck A is RV311 (L-CH) and RV411 (R-CH), Deck B is RV301
(L-CH) and R V401 (R-CH) so that adjustment within specification
values as follows.

Specification V alues:

J101 PB 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

15

REC Bias Adjustment DECK B

r

r

Procedure:

1. Mode: Record
FUNCTION: VIDEO

MAIN board
VIDEO (AUDIO) IN jack (J101)
L-CH, R-CH



50 mV (– 23.8 dB)




600

Ω

AF OSC

1) 315 Hz

2) 10 kHz

attenuator

2. Mode: Playback

set

blank tape
CN-123

Specification values:

J101 PB level: 47.2 to 53.0 mV (- 24.3 to - 23.3 dB)

Adjustment Location: MAIN board

MAIN BOARD (Conductor Side)

RV301

L

IC301

RV351

R

REC LEVEL

VIDEO (AUDIO) IN

J101

MD OUT

(L/R)

(L/R)

recorded
portion

set

MAIN board
MD OUT jack (J101)
L-CH, R-CH

level mete

+
–

3. Confirm playback the signal recorded in step 1 become
specification values as follows.
If these values are out of specification values, adjust the RV341
(L-CH) and RV441 (R-CH) on the A UDIO board to repeat steps
1and 2.

Specification values: Playback output of 315 Hz to playback

output of 10 kHz: ± 0.5 dB

Adjustment Location: AUDIO board

REC Level Adjustment DECK B

Procedure:

1. Mode: Record
FUNCTION: VIDEO

MAIN board
VIDEO (AUDIO) IN jack (J101)
L-CH, R-CH

AF OSC

315 Hz, 50 mV (– 23.8 dB)

Ω

attenuator

600

blank tape
CS-123

set

AUDIO BOARD (Component Side)

RV441

RV401

RV301

LR

PB LEVEL

– DECK B –



IC602

RV341

RL



REC BIAS

CN601

RV311

LEAF SW BOARD (Component Side)

TAPE SPEED



(NORMAL) (HIGH)

RV1002



RV1001

CN1001

RV411

LR



PB LEVEL

– DECK A –

2. Mode: Playback

recorded
portion

set

MAIN board
MD OUT jack (J101)
L-CH, R-CH

level mete

+
–

3. Confirm playback the signal recorded in step 1 become
specification values as follows.
If these values are out of specification values, adjust the RV301
(L-CH) and R V351 (R-CH) on the MAIN board to repeat steps
1 and 2.

16

CD SECTION

V

)

+
–

(27 MHz)

VIDEO board

frequency counter

IC505

CN501

CN502

SL501

SL503

100

81

1

30

31

50

51

80

SL502

D502

Check point

(27 MHz)

(GND)

CT503
VIDEO

Frequency

Adjustment

Note:

1. CD Block is basically designed to operate without adjustment. There­fore, check each item in order given.

2. Use YEDS-18 disc (3-702-101-01) unless otherwise indicated.

3. Use an oscilloscope with more than 10 MΩ impedance.

4. Clean the object lens by an applicator with neutral detergent when the
signal level is low than specified value with the following checks.

S-Curve Check

oscilloscope

BD board

TP (FE)
TP (VC)

Procedure:

1. Connect oscilloscope to TP (FE).

2. Connect between TP (FE1) and TP (VC) by lead wire.

3. Connect between TP (AGCCON) and TP (GND) by lead wire.

4. Turn the power ON.

5. Load a disc (YEDS-18) and actuate the focus search. (In

consequence of open and close the disc tray, actuate the focus
search)

6. Cof irm that the oscilloscope waveform (S-curve) is symmetrical

between A and B. And confirm peak to peak level within
4 ± 1 Vp-p.

S-curve waveform

+
–

symmetry

E-F Balance (1 Track Jump) Check

oscilloscope

BD board

TP (TE)
TP (VC)

+
–

Procedure :

1. Connect oscilloscpe to TP (TE) and TP (VC).

2. Turn the power ON.

3. Load a disc (YEDS-18) and playback the number five track.

4. Press the ^ (CD) button. (Becomes the 1 track jump mode)

5. Confirm that the level B and A (DC voltage) on the oscilloscope
waveform.

1 track jump waveform

B

0V

level = 1.3

Specified level: × 100 = less than ± 22%

±

0.6 Vp-p symmetry

A
B

center of
waveform

A (DC voltage

6. After check, remove the lead wire connected in step 1.

VIDEO SECTION

Frequency Adjustment

Connection:

Procedure:

1. Connect the frequency counter to check point of the VIDEO
board.

2. Turned power switch on.

3. Press the FUNCTION button to select the CD.

4. Adjust CT503 on the VIDEO board so that the frequency counter
reading 27.0 MHz ± 80 Hz at stop status.

Adjustment Location:

VIDEO Board (SIDE B)

A

within 4

±

1 Vp-p

B

7. After check, remove the lead wire connected in step 2 and 3.

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 brightness
to obtain best waveform.

RF Level Check

oscilloscope

BD board

TP (RF)
TP (VC)

+
–

Procedure:

1. Connect oscilloscope to TP (RF).

2. Connect between TP (AGCCON) and TP (GND) by lead wire.

3. Turn the power ON.

4. Load a disc (YEDS-18) and press the ^ button to play.

5. Confirm that the oscilloscope waveform is clear and check RF
signal level is correct or not.

6. After check, remove the lead wire connected in step 2.

Note: Clear RF signal waveform means that the shape “≈” can be clearly

distinguished at the center of the waveform.

level:

1.45

VOLT/DIV: 200 m
TIME/DIV: 500 ns

±

0.3 Vp-p

Checking Location:

BD BOARD (Side B)

TP (AGCCON)

TP (RF)

IC102

TP (TE)

TP (FE)

IC103

TP (VC)

TP (GND)

TP (FE1)

IC101

1717

HCD-VX550

7-1. BLOCK DIAGRAM

CD SERVO SECTION

DETECTOR

A

B

C

D

I-V AMP

F

E

OPTICAL PICK-UP
(KSS-213D/Q-NP)

SECTION 7

DIAGRAMS

LPH

CTL1

FILTER

RF AMP,

A+5V

7

4

2

1

5

10

6

5

6

7

8

10

11

FOCUS/TRACKING ERROR AMP

A

B

C

D

F

F I-V AMP

E

E I-V AMP

IC103

RF

SUMMING

AMP

RF EQ

AMP

FOCUS

ERROR AMP

TRACKING

ERROR AMP

RFO

HOLD SW

16

FE

14

TE

13

LPH

21

DIGITAL SIGNAL PROCESSOR

IC101 (1/2)

RFAC

50

49
48

ASYMMETRY

CORRECTOR
ASYI
ASYO

DIGITAL

CLV

PROCESSOR

MDP

25 76 77

53 55

FILI

PCO

FILO

CLTV

DIGITAL PLL

TO SERVO AUTO

SEQUENCER

CPU INTERFACE

SENSE

DATA

CLOK

XLAT

125254

XPCK

EFM

DEMODULATOR

RAM

INTERNAL BUS

CORRECTOR

SUBCODE

PROCESSOR

EXCK

SCOR

SBSO

SQCK

SQSO

79 801574 6 5 10 111368 3

WFCK

XUGF

GFS

EMPH

32K

ERROR

16 69

C4M

CLOCK

GENERATOR

D/A

DIGITAL

INTERFACE

MUTE

XTSL

DIGITAL

OUT

XTAO

XTAI

PCMD

BCK
LRCK
C2PO

WDCK

DOUT

MD2

XRST

72
71

66
67
65
14
17

64

63

2

IC104

ADATA

D+5V

BCLK
LRCK
C2PO

OPTICAL

TRANSCEIVER

IC381

MCLK

33.8MHz

DATA, BCK,

LRCK, C2PO

CD DIGITAL OUT

OPTICAL

A

B

(Page 19)

(Page 19)

LASER DIODE

2-AXIS

DEVICE

(TRACKING)

(FOCUS)

LDON

22

LD

LD. DRIVER

LD

PD

M101

(SPINDLE)

M102

(SLED)

T+
T–

F+
F–

Q101

FOCUS/TRACKING COIL DRIVE,

SPINDLE/SLED MOTOR DRIVE

+

M

+

M

VO3(+)

17

VO3(–)

18

VO4(+)

15

VO4(–)

16

VO2(+)

12

VO2(–)

11

VO1(+)

14

VO1(–)

13

3

IC102

MOTOR

DRIVE

MOTOR

DRIVE

COIL

DRIVE

COIL

DRIVE

APC LD

AMP

OPIN3(–)

OPIN4(+)
OPIN4(–)

OPIN2(+)
OPIN2(–)

OPIN1(+)
OPIN1(–)

APC PD

AMP

23

27
26

5
6

2
3

PD

4

DIGITAL SERVO

SFDR

29

SRDR

30

TFDR

31

TRDR

32

FFDR

33

FRDR

34

PROCESSOR

IC101 (2/2)

PWM GENERATOR

FOCUS/TRACKING/SLED

40 41 39 43

FE

TE

SE

RFDC

A/D

CONVERTER

FOCUS/

TRACKING/SLED

SERVO DSP

MIRR,

DFCT, FOK

DETECTOR

SERVO

INTERFACE

SERVO AUTO

SEQUENCER

FOK

MIRR

DFCT

COUT
SCLK

3 5 4 1 18 36 37 10

SCOR

SENSE

DSP CLK

DSP DATA

DSP LATCH

LDON

SENSE CLK

28 2

DISC IN DETECT

SENSOR

LEVEL SHIFT

22
20
21

19

8

SUBQ CLK

SUBQ DATA

CD MECHANISM CONTROLLER

IC505 (1/2)

DISC TRAY

SENSOR

IC703

Q701

60 61 71 70 69 68 59

DISC-SENS

TBL-L

TBL-R

65 63 67

IC702

LOAD-OUT

LOAD-IN

66

DISC TRAY SLIDE MOTOR DRIVE

10

2

T-SENS

FIN
RIN

(OPEN/CLOSE DET)

CLOSE

OUT-OPEN

IC801

MOTOR

DRIVE

S801

OPEN

SYSTEM CONTROLLER

IC501 (1/4)

OUT1

7

OUT2

4

DSP MUTE

DEVICE RESET

DISC TRAY

ADDRESS DETECT

ROTARY

ENCODER

S811

4 2 3

ENC1

ENC2

M

(DISC TRAY SLIDE)

CTRL1
CTRL2

XRESET

ENC3

M801

XRST

CTL1

LPH

RESET

C

(Page 19)

11
19

77
12

STBY2STBY1

209

SSTP
26

A+5V

TO CPU INTERFACE

S101

(LIMIT)

DISC TRAY TURN MOTOR DRIVE

3
6

IN1
IN2

IC701

MOTOR

DRIVE

OUT1
OUT2

7
2

M

(DISC TRAY TURN)

M701

• SIGNAL PATH
: CD PLAY

16

: DIGITAL OUT

1818

HCD-VX550

AUDIO/VIDEO CD SECTION

MCLK 33.8MHz

A

(Page 18)

DATA, BCK,

B

(Page 18)

LRCK, C2PO

DATA

BCK

LRCK

C2PO

LEVEL

SHIFT
IC501

MPEG VIDEO/AUDIO DECODER,

VIDEO SIGNAL PROCESSOR

IC506

CD-DATA

180

CD-BCK

184

CD-LRCK

182

CD-C2PO

185

100,98,114,116,118,120,121,122,124

ADDRESS BUS

DATA BUS

CD-ROM

INTERFACE

CIRCUIT

MA0 – MA10

104,110,112,111,108,105,102,99,96,

A0 – A18

MPEG

SYSTEM

DECODER

D-RAM/ROM INTERFACE

MD0 – MD15

54,58,60,64,68,72,74,78,

76,73,70,66,62,59,56,53

MPEG

AUDIO

DECODER

MPEG
VIDEO

DECODER

D0 – D15

MCE

128

VIDEO

PROCESS

CIRCUIT

SD-RAS

MWE

82 86 85

AUDIO

INTERFACE

CIRCUIT

SD-CAS

SD-CSO

90

VDATA0 – 7

CPU INTERFACE

INT

RESET

13 16

DA-DATA

DA-BCK

DA-LRCK

DA-XCLK

SYS CLK

VCK-IN
HSYNC
VSYNC

161
167
166

169

178

150,152,154,155

142,143,145,148,

177
157
158

DATA

CLK

OSC

BUFFER

IC510

VIDEO FREQUENCY

CT503

(27MHz)

DATA

18

BCK

17

LRCK

19

768FSO

21

384FSO

20

MCKO

4

INPUT

INTERFACE

CIRCUIT

TIMING CONTROL/

CLOCK GENERATOR

XT2

X503

27MHz

XT1

DIGITAL FILTER,
D/A CONVERTER

DIGITAL

FILTER,

NOISE
SHAPER
CIRCUIT

IC509

D/A

CONVERTER

MODE

CONTROL

MC

MD

9 724 1

8

(Page 21)

R-CH

CD-L

E

• SIGNAL PATH

VOUTL

LOW-PASS

FILER

ML

RSTB

10

VOUTR

14

11

LOW-PASS

FILER
IC515

: CD PLAY (AUDIO)
: CD PLAY (VIDEO)

(Page 18)

RESET

PCL

4

DATA

3

CLK

1

HSYNC

20

VSYNC

19

D/A

V-B
V-G
V-R

18
17
16

C

21 – 24, 27 – 32,20

A0 – A10 BA

D-RAM

IC507

DATA, CLK

D

(Page 22)

A0 – A10

A11

2,3,5,6,8,9,11,12,39,

19

40,42,43,45,46,48,49

RAS

WE

CAS

17 1516

D0 – D15

DQ0 – DQ15

HSY

28

VSY

27

VCLK

51

2

–

8
,

10

NTB

22

D/A CONVERTER

IC511

YUV0 – 7

DIGITAL RGB ENCORDER

IC514

64 157

ROSD

GOSD

OSD

TIMING

CONTROL

Y/C

FILTER

BOSD

D/A

COUT
YOUT

VOUT

J301

S VIDEO OUT

37
45

39

C

Y

1

3
4

2

J302

VIDEO OUT

DF LATCH

A0 – A10

12 – 5, 27, 26, 23

A0 – A10

CS

18

PROGRAM ROM

IC508

D0 – D7

13 – 15, 17 – 21

O0 – O7

A11–A17

25, 4, 28, 29, 3, 2, 30

A11 – A17

CE

22

NTSC

AUTO

PAL

S501

SYSTEM SELECT

(SELF DIAGNOSIS)

I2C CLK

I2C DATA

D502

CLK1

33

DATA1O

31

20

CL680 HINT

24

8830 RESET

CD MECHANISM CONTROLLER

IC505 (2/2)

93

NT/PAL

TEST LED

73

NT/PAL OUT

29

I2C/RX
I2C/TX

30

22

27MHz

VD0 – VD7

21

XOUT

XIN

1315

X501

16

10MHz

1919

HCD-VX550

TAPE DECK SECTION

HP101

(PLAYBACK)

L-CH

R-CH R-CH

HRPE101 (1/2)

(RECORD/PLAYBACK)

L-CH

R-CH R-CH

DECK PROCESS

DECK A/B SELECT, PB/REC EQ AMP,

DOLBY NR AMP, ALC, AMS

IC301

DOLBY PASS

NORM/HIGH

PB A/B

70

120

R-CH

NR ON/OFF

BIAS ON/OFF

RM ON/OFF

L.P.F.

BUFFER

28

27

AMS

CIRCUIT

REC/PB/PASS

LM ON/OFF

26

+

MAOUT

MSIN

MSOUT

RIN (L)

43

ALC (L)

44

DOLBY NR

ALC

ROUT (L)

ALC

35 34

AMP

CIRCUIT

IN (L)

REC OUT (L)

39

RV301

REC LEVEL (L)

(DECK B)

EQ IN (L)

38

PB EQ AMP

(DECK A)

IC611

PB EQ AMP

(DECK B)

IC601

REC/PB SWITCHING

3

1

R-CH

IC602

R-CH

RV311

PB LEVEL (L)

(DECK A)

RV301

PB LEVEL (L)

(DECK B)

4

AIN (L)

48

BIN (L)

46

BIAS (N)

33

BIAS (C)

32

BIAS (M)

31

S1004

(DECK A 120/70)

S1008

(DECK B 120/70)

BIAS

CONTROL

CIRCUIT

B NORM/CROM

ALC ON/OFF

A 120/70

1516182022 23242517

19

REC

EQ AMP

PB OUT (L)

EQ OUT

40

(L)

36

PB-L

REC-L

F

(Page 21)

G

(Page 21)

• SIGNAL PATH
: PLAYBACK (DECK A)

: PLAYBACK (DECK B)
: RECORD

RV441

REC BIAS (R)

(DECK B)

HRPE101 (2/2)

(ERASE)

R-CH

16

2

RV341

REC BIAS (L)

(DECK B)

BIAS OSC

T621

BIAS OSC

Q621, 622

REC BIAS

SWITCH

Q623

C331, L331

BIAS

TRAP

B+

(A+7V)

D+5V

100

TC-RELAY

(DECK A PLAY)

8584838281 807978

PB-A/B

EQ-H/N

ALC-ON/OFF

A-PLAY-SW

87

S1001

S1002

(DECK B PLAY)

BIAS

REC-MUTE

B-PLAY-SW

86

TC-MUTE

R/P-PASS

NR-ON/OFF

(DECK A HALF)

S1003

77

AMS-IN

A-HALF

88

ROTATION

DETECT SENSOR

(DECK A)

IC1001

91

A-SHUT

S1006

(DECK B HALF)

S1005

(DECK A REC)

S1009

(DECK B REC)

ROTATION

DETECT SENSOR

(DECK B)

IC1002

90

B-SHUT

SYSTEM CONTROLLER

B-HALF

89

IC501 (2/4)

TRIGGER PLUNGER

DECK A

TRIGGER

PLUNGER DRIVE

(DECK A)

Q333, 334

73

A-TRG

TRIGGER PLUNGER

DECK B

TRIGGER

PLUNGER DRIVE

(DECK B)

Q331, 332

72

B-TRG

Q335

76

CAP-M-H/L

RV1001

TAPE SPEED

(HIGH)

CAPM-CNT1
CAPM-CNT2

CAPSTAN MOTOR

CONTROL SWITCH

Q1001

75

MOTOR DRIVE

74

RV1002

TAPE SPEED

(NORMAL)

CAPSTAN

Q336 – 343

M

M1

(CAPSTAN)

2020

HCD-VX550

MAIN SECTION

J711

MIC 2

J712

MIC 1

VIDEO

MD IN

CD-L

E

PB-L

F

(Page 19)

(Page 20)

(AUDIO) IN

FM

75Ω

J101 (1/2)

L

R

L

R

ANTENNA

R-CH

R-CH

DIGITAL ECHO

IC711

MIC AMP

IC712 (1/2)

GRAPHIC EQUALIZER CONTROL,

IN E2

65

IN D2

66

IN B2

68

IN A2

69

IN C2

67

FM/AM TUNER UNIT

FM ANT

FM ANT

RV712

MIC LEVEL

INPUT SELECT SWITCH,

ELECTRICAL VOLUME

IC101

INPUT
SELECT
SWITCH

R-CH

ST-L

ST-R

R-CH

RV711

ECHO
LEVEL

MIC AMP

IC712 (2/2)

SOUND

CONTROL

CIRCUIT

KEY IN2

60 5

R-CH

KEY IN1

40

11

R-CH

3

VC L+R/L–R

L-IN

L+R/L–R

493-DATA

493-LATCH

BASS FREQ.

2 58 57

+

493-CLK

DBFB-H/L

MIC IN

+

+

KEY OUT 1
KEY OUT 2

L+R/L–R

MATRIX

CIRCUIT

47
48
38

7

44

L+R

23 24

REC A2

GRAPHIC EQUALIZER

CONTROL CIRCUIT

R-CH

30

6

R-CH

59

ADM L.P.F.

OSC

LC-INELC-INB

OSC

D607
D644

S-RAM

F OUT2

L/R+DELAY

CIRCUIT

REC B2

42 41

+

EFFECT/
BYPASS

SURROUND
PROCESSOR

IC1201

VOL
IN2

COMMAND

L-OUT

14

VOLUME

CONTROL

R-CH

+

CPU

INTERFACE

DATA

CLOCK

LATCH
34

BASS BOOST

CONTROL

CIRCUIT

BB B2,

BB A2

38, 39

DBFB CONTROL

SWITCH

Q111

SUPER

WOOFER

BUF IN2

373233

BASS FREQUENCY

CONTROL SWITCH

Q201

R-CH

BUF

OUT2

FEED BACK

R-CH

72

36

SWITCH

Q112

R-CH

D141

R-CH

+

D191

PROTECT

SWITCH

R-CH

Q192

REC-L

SPEANA

J101 (2/2)

L

R-CH

MUTING

Q191

–1

R

SUPER WOOFER

FAN MOTOR

DRIVE

Q401, 402

USE 8 – 16Ω

G

H

MD OUT

J191

TM401

SPEAKER

IMPEDANCE

(Page 20)

(Page 22)

M501
(FAN)

M

+

L

–2

–
+

R

–

AM

• SIGNAL PATH
: TUNER (FM/AM)

: CD PLAY
: TAPE PLAY

: RECORD
: MIC INPUT

(Page 22)

I

RESET

AM ANT

AM ANT

ST-MUTE

STEREO

TUNED
ST-DIN

ST-DOUT

ST-CLK

ST-CE

49

ST-MUTE
STEREO

50

TUNED

51

ST-DOUT

53
54

ST-DIN
ST-CLK

55

ST-CE

52

SYSTEM CONTROLLER

IC501 (3/4)

AC-CUT

RESET

F-RELAY

RY-SW

1

MUTING CONTROL

6

22

12

27

3

36

RESET SWITCH

Q501

STK-MUTE

LINE-MUTE

XC-OUT

X601

32.768kHz

X613

16MHz

16

11

XC-IN

10

13

X-OUT

X-IN

15

PROTECTOR

SWITCH

Q508, 509

MUTING

Q113

R-CH

POWER AMP

STANDBY SWITCH

Q803, 804, 881

+5V

RESET SIGNAL

GENERATOR

IC502

IC801

R-CH

TH831

TEMPERATURE

DETECT SWITCH

Q831, 832

MUTING CONTROL

SWITCH

Q412

R-CH

OVER LOAD

DETECT

Q801

DC DETECT

+

SWITCH

Q433, 434

D803

+

PROTECT SWITCH

OVER LOAD

DETECT SWITCH

Q439

Q432

R-CH

OVER LOAD

DETECT SWITCH

Q437

PROTECT SWITCH

Q435, 436

MUTING

Q411, 471

RELAY
DRIVE

Q431

J701

PHONES

RY401

2121

HCD-VX550

DISPLAY/KEY CONTROL/POWER SUPPLY SECTION

GRID DRIVE
Q607 – 612

FL601

FLUORESCENT INDICATOR TUBE

GRID DRIVE

Q613

FLUORESCENT INDICATOR TUBE DRIVER,

45

KEY CONTROL

46 – 67

S1 – S22

32 – 27

G13 – G18

G2 – G12

44 – 42, 40 – 33

G1

IC601

S LOW FREQ (BPF0)

BPF1
BPF2

BPF3
BPF4

ALL BAND (L+R)

RESET

L SEL

16
17
18
19
20

21

73

7

17
16
14
13
12

11

F01
F02
F04
F05
F06

L+R

LED DRIVER

IC604

DET

DET

BAND-PASS FILTER

IC603

B.P.F.

LINE

REC IN

(Page 21)(Page 21)

H

SPEANA

IN

4

6

B+ SWITCH

Q601, 602

Q603

I

RESET

+5V (LED)

TO FLUORESCENT

INDICATOR TUBE

(FL601)

VF1
VF2

POWER TRANSFORMER

T951

S611 – 630, 632 – 635,
S638 – 651, 751 – 757

REMOTE CONTROL

RECEIVER

IC602

S601

(JOG DIAL)

S602

VOLUME

DATA, CLK

D

(Page 19)

16

ROTARY

ENCODER

S601

ROTARY

ENCODER

S602

11 – 14

1

2
8

9

10

78
79

KEY0 – KEY3

SIRCS

JOG-A
JOG-B

VOL-A
VOL-B

I2C DATA

I2C CLK

XOUT

72 70

X601

12.5MHz

LED DATA

LED SCK

LED LAT

WAKE UP

XIN

5
3
4

22

DATA

13
14

CLK

15

STB

SYSTEM CONTROLLER

IC501 (4/4)

WAKE UP

18

30

IIC-DATA

29

IIC-CLK

P1 – P9, P11, P12, P15, P16

17, 19 – 23, 1 – 3, 5, 7, 10, 11

POWER

5

2

39

26

CD-POWER

STBY LED

TIMER LED

D611 – 624,
D627 – 631,

D751 – 753

LED DRIVE
Q604, 605

LED DRIVE

Q606

A+5V (SW)

D/A CONVERTER (IC509),

VIDEO AMP CIRCUIT B+

D+5V (SW)

M62493FP (IC101),

CD SENSOR CIRCUIT B+

D754

I/u

D632

TIMER SELECT

B+ SWITCH

Q904, 905

+5V

SYSTEM CONTROLLER

(IC501) B+

+5V

CD MECHANISM

CONTROLLER (IC505) B+

+5V (STBY)

(PANEL SECTION B+)

D+5V (UNSW)

(TAPE DECK SECTION B+)

+5V (LED)

(PANEL SECTION B+)

D923

D501, 502

D507

D509

D922

D924

D+5V (SW)

CD SERVO/VIDEO CD

SECTION B+

+3.3V

MPEG VIDEO/AUDIO

DECODER (IC506) B+

REGULATOR

CONTROL SWITCH

Q903, 923

+3.3V

REGULATOR

IC504

TC, PANEL,

AUDIO

CD M+7V

(CD MOTOR SECTION B+)

TC M+12V

(TC MOTOR SECTION B+)

ST +10V

(FM/AM TUNER UNIT B+)

CD M+12V

(CD MOTOR SECTION B+)

POWER AMP (IC801),
PROTECTOR CIRCUIT

–26V

(FL DRIVER (IC601) B–)

REGULATOR

REGULATOR

B+ SWITCH

Q911, 912

A+7V

A–7V

REGULATOR

FAN MOTOR B–

+10V

REGULATOR

Q909

+5V

IC902

+5V

IC101

+5V

IC904

REGULATOR

Q901, 902, 913

REGULATOR

Q914, 951, 952

+VL
–VL

+VH
–VH

–26V REGULATOR

Q971

+7V

–7V

D405 – 407

+7V

REGULATOR

IC901

+12V

REGULATOR

IC903

RECT
D832

RECT
D831

RECT
D971

RECT

D901 – 904

RECT

D907 – 910

AC IN

2222

HCD-VX550

CD SW board

TRANS board

MAIN board

PANEL board

TUNER (FM/AM)

SURROUND board

VIDEO board

5V POWER board

CONNECTOR board

SENSOR board

MOTOR (TURN) board

MOTOR (SLIDE) board

LEAF SW board

AUDIO board

BD board

THIS NOTE IS COMMON FOR PRINTED WIRING BOARDS AND SCHEMATIC DIAGRAMS.
(In addition to this, the necessary note is printed in each block.)

Note on Printed Wiring Board:

• X : parts extracted from the component side.

• p : parts mounted on the conductor side.

• b : Pattern from the side which enables seeing.

(The other layers' patterns are not indicated.)

Caution:
Pattern face side: Parts on the pattern face side seen from
(Side B) the pattern face are indicated.
Parts face side: Parts on the par ts face side seen from
(Side A) the parts face are indicated.

• Indication of transistor.

C
Q

B

E

B

B

These are omitted.

Q

CE

These are omitted.

Q

CE

These are omitted.

Note on Schematic Diagram:

• All capacitors are in µF unless otherwise noted. pF: µµF
50 WV or less are not indicated except for electrolytics
and tantalums.

• All resistors are in Ω and 1/
specified.

¢

•

• 2 : nonflammable resistor.

• 5 : fusible resistor.

• C : panel designation.

• U : B+ Line.

• V : B– Line.

• H : adjustment for repair.

• Voltages are taken with a VOM (Input impedance 10 MΩ).

• Waveforms are taken with a oscilloscope.

• Circled numbers refer to waveforms.

• Signal path.

: internal component.

The components identified by
mark ! or dotted line with mark
! are critical for safety.
Replace only with part number
specified.

Voltage variations may be noted due to normal produc­tion tolerances.

Voltage variations may be noted due to normal produc­tion tolerances.

F : TUNER (FM/AM)
E : PLAYBACK (DECK A)
d : PLAYBACK (DECK B)
G : RECORD
L : CD PLAY (VIDEO)
J : CD PLAY (AUDIO)
c : DIGITAL OUT
N : MIC INPUT

4

7-2. CIRCUIT BOARD LOCATION

W or less unless otherwise

2323

HCD-VX550

7-3. PRINTED WIRING BOARD BD BOARD • Refer to page 23 for Circuit Boards Location.

(Page 28)

2424

7-4. SCHEMATIC DIAGRAM BD BOARD • Refer to page 29 for Waveforms. • Refer to page 45, 46 for IC Block Diagrams.

HCD-VX550

(Page 26)

• Voltages and waveforms are dc with respect to ground
under no-signal conditions.
no mark : CD STOP
( ) : CD PLAY

The components identified by
mark ! or dotted line with mark
! are critical for safety.
Replace only with part number
specified.

2525