Zenith XBV323 Schematic

SERVICE MANUAL

Product Type: DVD+VCR
Chassis: D35 (DECK), DP-7C(MD)
Manual Series: XBV323
Manual Part #: 3829RVN006P
Model Line: F
Product Year: 2003

Summary 1
Cabinet & Main Chassis 2
Electrical 3
Mechanism of VCR Part 4
Mechanism of DVD Part 5
Parts List 6

Published September 2003

by Technical Publications

Zenith Electronics Corporation

201 James Record Road

Huntsville, Alabama 35824-1513

Copyright © 2003 by Zenith Electronics Corporation

Model Series:

CONTENTS

XBV323

....................................................

.............................

....................................................

.............................

.............................

....................................................

1-1

SECTION 1

SUMMARY

CONTENTS

PRODUCT SAFETY SERVICING GUIDELINES FOR VIDEO PRODUCTS ............. 1-2

SERVICING PRECAUTIONS .................................................................................................. 1-3

SPECIFICATIONS ...................................................................................................................... 1-4

1-2

IMPORTANT SAFETY NOTICE

This manual was prepared for use only by properly trained audio-video service
technicians.

When servicing this product, under no circumstances should the original
design be modified or altered without permission from Zenith Electronics
Corporation. All components should be replaced only with types identical to
those in the original circuit and their physical location, wiring and lead dress
must conform to original layout upon completion of repairs.

Special components are also used to prevent x-radiation, shock and fire haz­ard. These components are indicated by the letter “x” included in their compo­nent designators and are required to maintain safe performance. No deviations
are allowed without prior approval by Zenith Electronics Corporation.

Circuit diagrams may occasionally differ from the actual circuit used. This way,
implementation of the latest safety and performance improvement changes
into the set is not delayed until the new service literature is printed.

CAUTION: Do not attempt to modify this product in any way. Never perform
customized installations without manufacturer’s approval. Unauthorized modi­fications will not only void the warranty, but may lead to property damage or
user injury.

Service work should be performed only after you are thoroughly familiar with
these safety checks and servicing guidelines.

GRAPHIC SYMBOLS

The exclamation point within an equilateral triangle is intended to
alert the service personnel to important safety information in the
service literature.

The lightning flash with arrowhead symbol within an equilateral tri­angle is intended to alert the service personnel to the presence of
noninsulated “dangerous voltage” that may be of sufficient magni­tude to constitute a risk of electric shock.

The pictorial representation of a fuse and its rating within an equi­lateral triangle is intended to convey to the service personnel the
following fuse replacement caution notice:

CAUTION: FOR CONTINUED PROTECTION AGAINST RISK
OF FIRE, REPLACE ALL FUSES WITH THE SAME TYPE AND
RATING AS MARKED NEAR EACH FUSE.

SERVICE INFORMATION

While servicing, use an isolation transformer for protection from AC line shock.
After the original service problem has been corrected, make a check of the fol­lowing:

FIRE AND SHOCK HAZARD

1. Be sure that all components are positioned to avoid a possibility of adjacent
component shorts. This is especially important on items trans-ported to and
from the repair shop.

2. Verify that all protective devices such as insulators, barriers, covers, shields,
strain reliefs, power supply cords, and other hardware have been reinstalled
per the original design. Be sure that the safety purpose of the polarized line
plug has not been defeated.

3. Soldering must be inspected to discover possible cold solder joints, solder
splashes, or sharp solder points. Be certain to remove all loose foreign par­ticles.

4. Check for physical evidence of damage or deterioration to parts and compo­nents, for frayed leads or damaged insulation (including the AC cord), and
replace if necessary.

5. No lead or component should touch a high current device or a resistor rated
at 1 watt or more. Lead tension around protruding metal surfaces must be
avoided.

6. After reassembly of the set, always perform an AC leakage test on all
exposed metallic parts of the cabinet (the channel selector knobs, antenna
terminals, handle and screws) to be sure that set is safe to operate without
danger of electrical shock. DO NOT USE A LINE ISOLATION TRANS­FORMER DURING THIS TEST. Use an AC voltmeter having 5000 ohms per
volt or more sensitivity in the following manner: Connect a 1500 ohm, 10
watt resistor, paralleled by a .15 mfd 150V AC type capacitor between a
known good earth ground water pipe, conduit, etc.) and the exposed metal­lic parts, one at a time. Measure the AC voltage across the combination of
1500 ohm resistor and .15 mfd capacitor. Reverse the AC plug by using a
non-polarized adaptor and repeat AC voltage measurements for each
exposed metallic part. Voltage measured must not exceed 0.75 volts RMS.
This corresponds to 0.5 milliamp AC. Any value exceeding this limit consti­tutes a potential shock hazard and must be corrected immediately.

TIPS ON PROPER INSTALLATION

1. Never install any receiver in a closed-in recess, cubbyhole, or closely fitting
shelf space over, or close to, a heat duct, or in the path of heated air flow.

2. Avoid conditions of high humidity such as: outdoor patio installations where
dew is a factor, near steam radiators where steam leakage is a factor, etc.

3. Avoid placement where draperies may obstruct venting. The customer
should also avoid the use of decorative scarves or other coverings that
might obstruct ventilation.

4. Wall- and shelf-mounted installations using a commercial mounting kit must
follow the factory-approved mounting instructions. A product mounted to a
shelf or platform must retain its original feet (or the equivalent thickness in
spacers) to provide adequate air flow across the bottom. Bolts or screws
used for fasteners must not touch any parts or wiring. Perform leakage tests
on customized installations.

5. Caution customers against mounting a product on a sloping shelf or in a tilt­ed position, unless the receiver is properly secured.

6. A product on a roll-about cart should be stable in its mounting to the cart.
Caution the customer on the hazards of trying to roll a cart with small cast­ers across thresholds or deep pile carpets.

7. Caution customers against using extension cords. Explain that a forest of
extensions, sprouting from a single outlet, can lead to disastrous conse­quences to home and family.

A.C. Voltmeter

1500 OHM

10 WATT

Place this probe
on each exposed
metal part.

Good Earth Ground
such as the Water
Pipe, Conduit, etc.

0.15uF

PRODUCT SAFETY SERVICING GUIDELINES FOR VIDEO PRODUCTS

1-3

SERVICING PRECAUTIONS

CAUTION: Before servicing the DVD+VCR covered by this
service data and its supplements and addends, read and fol­low the

SAFETY PRECAUTIONS. NOTE: if unforeseen cir­cumstances create conflict between the following servicing
precautions and any of the safety precautions in this publi­cations, always follow the safety precautions.

Remember Safety First:

General Servicing Precautions

1. Always unplug the DVD+VCR AC power cord from the AC

power source before:
(1) Removing or reinstalling any component, circuit board,

module, or any other assembly.

(2) Disconnecting or reconnecting any internal electrical

plug or other electrical connection.

(3) Connecting a test substitute in parallel with an elec-

trolytic capacitor.
Caution: A wrong part substitution or incorrect
polarity installation of electrolytic capacitors may result
in an explosion hazard.

2. Do not spray chemicals on or near this DVD+VCR or any

of its assemblies.

3. Unless specified otherwise in this service data, clean

electrical contacts by applying an appropriate contact
cleaning solution to the contacts with a pipe cleaner,
cotton-tipped swab, or comparable soft applicator.
Unless specified otherwise in this service data, lubrication
of contacts is not required.

4. Do not defeat any plug/socket B+ voltage interlocks with

whitch instruments covered by this service manual might
be equipped.

5. Do not apply AC power to this DVD+VCR and / or any of

its electrical assemblies unless all solid-state device heat
sinks are correctly installed.

6. Always connect the test instrument ground lead to an

appropriate ground before connecting the test instrument
positive lead. Always remove the test instrument ground
lead last.

Insulation Checking Procedure

Disconnect the attachment plug from the AC outlet and turn
the power on. Connect an insulation resistance meter (500V)
to the blades of the attachment plug. The insulation resis­tance between each blade of the attachment plug and acces­sible conductive parts (Note 1) should be more than 1M­ohm.
Note 1: Accessible Conductive Parts include Metal panels,
Input terminals, Earphone jacks,etc.

Electrostatically Sensitive (ES) Devices

Some semiconductor (solid state) devices can be damaged
easily by static electricity. Such components commonly are
called Electrostatically Sensitive (ES) Devices. Examples of
typical ES devices are integrated circuits and some field
effect transistors and semiconductor chip components.
The following techniques should be used to help reduce the
incidence of component damage caused by static electricity.

1. Immediately before handling any semiconductor compo­nent or semiconductor-equipped assembly, drain off any
electrostatic charge on your body by touching a known
earth ground. Alternatively, obtain and wear a commer­cially available discharging wrist strap device, which
should be removed for potential shock reasons prior to
applying power to the unit under test.

2. After removing an electrical assembly equipped with ES
devices, place the assembly on a conductive surface such
as aluminum foil, to prevent electrostatic charge buildup or
exposure of the assembly.

3. Use only a grounded-tip soldering iron to solder or unsolder
ES devices.

4. Use only an anti-static solder removal device. Some
solder removal devices not classified as “anti-static” can
generate electrical charges sufficient to damage ES
devices.

5. Do not use freon-propelled chemicals. These can
generate an electrical charge sufficient to damage ES
devices.

6. Do not remove a replacement ES device from its protec­tive package until immediately before you are ready to
install it. (Most replacement ES devices are packaged with
leads electrically shorted together by conductive foam,
aluminum foil,or comparable conductive material).

7. Immediately before removing the protective material from
the leads of a replacement ES device, touch the protective
material to the chassis or circuit assembly into which the
device will be installed.

Caution: Be sure no power is applied to the chassis or
circuit, and observe all other safety precautions.

8. Minimize bodily motions when handling unpackaged
replacement ES devices. (Normally harmless motion such
as the brushing together of your clothes fabric or the lifting
of your foot from a carpeted floor can generate static elec­tricity sufficient to damage an ES device.)

1-4

SPECIFICATIONS

General

Power requirements AC 120V ,60 Hz
Power consumption 23W
Dimensions (approx.) 430 X 97.5 X 293 mm (16.9 x 3.9 x 11.5 inches)(w x h x d)
Mass (approx.) 4.8 kg (10.58 lbs)
Operating temperature 5 °C to 40 °C (41 °F to 104 °F)
Operating humidity 5 % to 90 %
Signal system NTSC

Inputs

ANTENNA IN Antenna or CATV input,75 ohms
VHS VIDEO IN 1 Vp-p 75 ohms,sync negative,RCA jack x 1
VHS AUDIO IN -6.0 dBm more than 47 ohms,RCA jack (L,R)x 1

Outputs

VIDEO OUT 1 Vp-p 75 ohms,sync negative
S-VIDEO OUT (Y)1.0 V (p-p),75 ohms,negative sync,Mini DIN 4-pin x 1

(C)0.3 V (p-p)75 ohms

COMPONENT VIDEO OUT (Y)1.0 V (p-p),75 ohms,negative sync,RCA jack x 1

(Pb)/(Pr)0.7 V (p-p),75 ohms,RCA jack x 2
Audio output (digital audio) 0.5 V (p-p),75 ohms,RCA jack x 1
Audio output (analog audio) 2.0 Vrms (1 KHz,0 dB),330 ohms,RCA jack (L,R)x 1
RF OUT Channel 3 or 4

VCR Specifications

Head system Four head helical scan azimuth system
TTimer 12-hour display type with AM,PM
Tape speed SP:33.35 mm/sec,LP:16.67 mm/sec,SLP:11.12 mm/sec
Tape width 12.7 mm
Maximum recording time SP:2 HOURS (T-120),SLP:6 HOURS (T-120)/8 HOURS (T-160)
Rewind time About 3 minutes (T-120)
Antenna 75 ohms (VHF/UHF)
VHF output signal Channel 3 or 4 (Switchable)
Channel coverage VHF:2-13,UHF:14-69,CATV:1-125 (4A,A-W,W+1 -W+84,A-5 -A-1)
Frequency range 20Hz to 20kHz
Signal-to-noise ratio More than 43dB
Dynamic range More than 88 dB
Channel separation More than 60 dB

DVD Specifications

Laser system Semiconductor laser,wavelength 650 nm
Frequency response DVD (PCM 96 kHz):8 Hz to 44 kHz,

DVD (PCM 48 kHz):8 Hz to 22 kHz

CD:8 Hz to 20 kHz
Signal-to-noise ratio More than 100dB (ANALOG OUT jacks only)
Harmonic distortion Less than 0.008%
Dynamic range More than 95 dB (DVD/CD)

Accessories:

Video cable x 1,Audio cable x 1,RF 75-ohm Coaxial Cable x 1,Remote control x 1,Batteries x 2

• Design and specifications are subject to change without prior notice.

FRONT VIEW (XBV323)

2-1

SECTION 2

CABINET & MAIN CHASSIS

CONTENTS

1. EXPLODED VIEWS ................................................................................................................2-2

1. Cabinet and Main Frame Section ...........................................................................................2-2

2. Packing Accessory Section....................................................................................................2-3

2-2

EXPLODED VIEWS

1. Cabinet and Main Frame Section

A43

A42

A49

280

465

250

467

467

467

284

283

LD601

300

330

276

260

A46

A46A

A48

A00

A26

285

457

457

457

457

467

467

452

274

452

330

323

A

5

4

3

2

1

BCD

2-3

2. Packing Accessory Section

BATTERY

808

BAG

804

PACKING

803

806

INSTRUCTION ASSEMBLY

CABLE(COAXIAL)

810

CABLE ASS'Y RF

801

REMOCON

900

BOX CARTON

802

PACKING

803

811

812

PLUG ASS'Y 1WAY

PLUG ASS'Y 2WAY

OPTIONAL PARTS

3-1

SECTION 3

ELECTRICAL

CONTENTS

OVERALL WIRING DIAGRAM..............................3-2

VCR PART

ELECTRICAL ADJUSTMENT
PROCEDURES

............................................................3-3

VCR ELECTRICAL TROUBLESHOOTING
GUIDE

.............................................................................3-4

1. POWER(SMPS) CIRCUIT .......................................3-4

2. SYSTEM/KEY CIRCUIT ..........................................3-7

3. SERVO CIRCUIT.....................................................3-8

4. OSD CIRCUIT .......................................................3-10

5. Y/C CIRCUIT .........................................................3-11

6. Hi-Fi CIRCUIT .......................................................3-13

7. Tuner/IF CIRCUIT .................................................3-18

BLOCK DIAGRAMS................................................3-20

1. Power (SMPS) BLOCK DIAGRAM ......................3-20

2. TU/IF BLOCK DIAGRAM......................................3-22

3. Y/C BLOCK DIAGRAM.........................................3-24

4. NORMAL AUDIO BLOCK DIAGRAM ..................3-26

5. Hi-Fi BLOCK DIAGRAM.......................................3-28

6. SYSTEM BLOCK DIAGRAM................................3-30

CIRCUIT DIAGRAMS..............................................3-32

1. Power (SMPS) CIRCUIT DIAGRAM ....................3-32

2. TU/IF CIRCUIT DIAGRAM....................................3-34

3. A/V CIRCUIT DIAGRAM .......................................3-36

4. Hi-Fi CIRCUIT DIAGRAM.....................................3-38

5. JACK CIRCUIT DIAGRAM ...................................3-40

6. SYSTEM CIRCUIT DIAGRAM ..............................3-42

7. TIMER CIRCUIT DIAGRAM..................................3-44

• WAVEFORMS .........................................................3-46

• CIRCUIT VOLTAGE CHART ..................................3-48

PRINTED CIRCUIT DIAGRAMS.........................3-50

1. VCR P.C.BOARD ..................................................3-50

2. KEY 1(LEFT) P.C.BOARD ....................................3-52

3. KEY 2(RIGHT) P.C.BOARD ..................................3-52

4. POWER P.C.BOARD ............................................3-54

DVD SECTION

ELECTRICAL TROUBLESHOOTING
GUIDE & WAVEFORMS

........................................3-56

1. SYSTEM OPERATION FLOW..............................3-56

2. TEST & DEBUG FLOW ........................................3-57

DETAILS AND WAVEFORMS ON
SYSTEM TEST AND DEBUGGING

...................3-63

1. SYSTEM 27MHZ CLOCK,

RESET, FLASH R/W SIGNAL ..............................3-63

2. SDRAM CLOCK....................................................3-63

3. TRAY OPEN/CLOSE SIGNAL ..............................3-64

4. SLED CONTROL RELATED SIGNAL

(NO DISC CONDITION) ........................................3-67

5. LENS CONTROL RELATED SIGNAL

(NO DISC CONDITION) ........................................3-67

6. LASER POWER CONTROL RELATED

SIGNAL(NO DISC CONDITION)...........................3-68

7. DISC TYPE JUDGEMENT WAVEFORMS............3-68

8. FOCUS ON WAVEFORMS ...................................3-70

9. SPINDLE CONTROL WAVEFORMS

(NO DISC CONDITION) ........................................3-71

10. TRACKING CONTROL RELATED

SIGNAL(SYSTEM CHECKING)..........................3-72

11. RF WAVEFORM ..................................................3-73

12. MT1379 AUDIO OPTICAL AND COAXIAL

OUTPUT (ASPDIF) .............................................3-73

13. MT1379 VIDEO OUTPUT WAVEFORMS...........3-74

14. AUDIO OUTPUT FROM AUDIO DAC ................3-75

BLOCK DIAGRAMS................................................3-77

1. OVERALL BLOCK DIAGRAM..............................3-77

2. SERVO BLOCK DIAGRAM ..................................3-78

3. MPEG & MEMORY BLOCK DIAGRAM ...............3-79

4. VIDEO & AUDIO BLOCK DIAGRAM ...................3-80

CIRCUIT DIAGRAMS..........................................3-81

1. SYSTEM CIRCUIT DIAGRAM ..............................3-81

2. RF & DSP SERVO CIRCUIT DIAGRAM ..............3-83

3. AUDIO CIRCUIT DIAGRAM .................................3-85

4. AV/JACK CIRCUIT DIAGRAM..............................3-87

• CIRCUIT VOLTAGE CHART ..................................3-89

PRINTED CIRCUIT DIAGRAMS.........................3-93

1. MTR P.C.BOARD ..................................................3-93

OVERALL WIRING DIAGRAM

3-2

PMC01

CFG

12VA(CAP)

5.2VA

CAP REV'H'

I-limit

MOTOR GND

GND

12VA(DRUM)

CAP CTL

LD IN

DFG/FG

DRUM CTL

1

2

3

4

5

6

7

8

9

10

11

12

1

2

3

4

5

6

7

8

9

10

11

12

PMP01

5.3VA

5.0V

GND

CAP Vcc

REG 12V

33V

12VA(DRUM)

PWR CTL 'H'

GND

NC

GND

GND

1

2

3

4

5

6

7

8

9

10

11

12

1

2

3

4

5

6

7

8

9

10

11

12

5.3VA

8V

GND(M)

REG 12V

3.3V5V3.3V

GND

GND

PDP01PPD01

123456789

123456789

PMD02

Vcc(HF)

RF

DVD_LD

DVD_PD

VOL(DVD)

GND

VC_INPUT

Vcc(HF)

F

E

A

D

C

B

F(+)

T(-)

T(+)

F(-)

Vcc

GND

CD_LD

CD_PD

VOL(CD)

123456789

10111213141516171819202122

23

123456789

10111213141516171819202122

23

PM601

GND

DISPLAY CLK

DISPLAY ENA

DISPLAY DATA

REMOCON

KEY RETURN 1

KEY RETURN 2

5.3VA

FD(-)

FD(+)

-27VA

GND

123456789

101112

123456789

101112

PM603

VIDEO IN

GND

AUDIO 'L'

GND

AUDIO 'R'

54321

54321

PMD03

SPM +

SPM -

FM +

FM -

LM -

LM +

SW(OPEN)

SW(CLOSE)

GND

SW(LEAD IN)

GND

123456789

10

11

123456789

10

11

P3D02

CTL(+)

CTL(-)

A/E(+)

A/E(-)

A.REC

A.PB

1

2

3

4

5

6

1

2

3

4

5

6

GND

FULL ERASE

P3D03

1

2

1

2

S/COMPO SW

COAXIAL

OPTICAL

GND

GND

K.RTN 2

DVD RESET

DVD ENA

DVD CLK

DVD DATA IN

DVD DATA OUT

GND

PVD02PMD01

1

2

3

4

5

6

7

8

9

10

11

12

1

2

3

4

5

6

7

8

9

10

11

12

Y

GND

Pb/C

GND

Pr

GND

C_V_OUT(DVD)

GND

D_A_L_OUT

GND

D_A_R_OUT

GND

A_MUTE_L

A_MUTE_R

GND

PDV03PMD02

1

2

3

4

5

6

7

8

9

10

11

12

13

14

15

1

2

3

4

5

6

7

8

9

10

11

12

13

14

15

GND

GND

DVD LED

VCR LED

5.3VA

K-RTN 1

K-RTN 2

GND

PM602PM603

1

2

3

4

5

6

7

8

1

2

3

4

5

6

7

8

DECK MD

MPEG

BOARD

SMPS

BOARD

TIMER

BOARD

KEY BOARD

VCR

3-3

ELECTRICAL ADJUSTMENT PROCEDURES

1. Servo Adjustment

1) PG Adjustment

• Adjustment And Specification

• Test Equipment

a) OSCILLOSCOPE
b) NTSC MODEL : NTSC SP TEST TAPE

MODE

PLAY

• Adjustment Procedure

a) Insert the SP Test Tape and play.
b) Connect the CH1 of the oscilloscope to the H/SW(W861, W862) and CH2 to the Video Out for the VCR.
c) Trigger the mixed Combo Video Signal of CH2 to the CH1 H/SW(W861, W862), and then check the dis-

tance (time difference), which is from the selected A(B) Head point of the H/SW(W861, W862) signal to
the starting point of the vertical synchronized signal, to 6.5H ± 0.5H (412µs, 1H=63µs).
Note - Adjust the distance of X, pressing the Tracking(+) or Tracking(-) when the “ATR” is blinking after

the SP Test Tape is inserted.

• PG Adjustment Method

a-1) Playback the SP standard tape
b-2) Press the “OK(ENTER)” key on the Remote controller and the “REC” key on the Front Panel at the

same time, then the unit will go in to Tracking initial mode.
c-3) Repeat the above step(No.b-2), then the unit finishes the PG adjusting automatically.
d-4) Stop the playback, then the unit goes out of PG adjusting mode after saving the PG data.

• CONNECTION

• WAVEFORM

V.Out

H/SW(W861, W862)

R/C TRK JIG KEY 6.5 ± 0.5H

MEASUREMENT POINT ADJUSTMENT POINT SPECIFICATION

V.Out

H/SW(W861, W862)

OSCILLOSCOPE

CH1 CH2

V.outH/SW

R/C KEY

(W861, W862)

H/SW

Composite

VIDEO

6.5H(412µs)

VCR PART

3-4

VCR ELECTRICAL TROUBLESHOOTING GUIDE

1. Power(SMPS) CIRCUIT

NO 5.3VA.

Replace F101.
(Use the same type)

Is F101 normal?

Is R101 normal?

Is BD101 normal?

NO

NO

NO

NO

NO

NO

Replace BD101.

Replace R101.

Is D102 normal?

Check or Replace
D102.

Replace D112.

Replace IC103.

YES

YES

YES

YES

YES

YES

Is Vcc(8.5~21V) sup­plied to IC101 Pin7?

NO

Is D112 normal?

Is there about 2.5V
at IC103 Vref?

Check the Main PCB

5.3VA/5.0V Line short?

(1) No 5.3VA (SYS/Hi-Fi/TUNER)

NO 12VA.

Check or Replace
D110.

Is the Vcc(13V) supplied
to (+) terminal in D115?

Check or Replace
the Motor Vcc.

Is the Vcc(12V) supplied
to (-) terminal in D115?

NO

NO

Replace D115.

YES

YES

(2) No 12VA (TO CAP, DRUM MOTOR)

NO 5.2VA.

5.3VA Line Check.

Is 5.3VA put into
Q160 Emitter?

Is about 5V put into
Q160 Base?

Is the Q162 Base
“H”?

NO

NO

Check the Power
Control.

NO

Check or Replace Q162,
R157, R158, R159, D121.

YES

Check or Replace
Q162/Q160.

YES

(3) No 5.2V (SYS/Hi-Fi/TUNER)

NO -27VA.

Check or Replace
D108.

(7) No -27VA

VCR ELECTRICAL TROUBLESHOOTING GUIDE

3-5

NO 5V.

5.3VA Line Check.

Is 5.3VA put into
Q160 Emitter?

Is about 5V put into
Q160 Base?

Is Q162 Base “H”?

NO

NO

NO

Check the Power
Control.

Check or Replace Q162,
R157, R158, R159, D121.

YES

YES

YES

Check or Replace
Q162/Q160

(4) No 5V (TO DVD)

No 33V.

Check the Power
Control.

Is Q162 Base “H”?

Check or Replace
Q161, R154, R155.

NO

YES

(5) No 33V (TUNER)

No REG 12V.

Check or Replace
D110.

Is 13V put into
Q156 Collector?

Is 13V put into
R153 Base?

NO

Check 33V Line.

NO

YES

Check or Replace Q156,
ZD103, R153, C151.

YES

(6) No REG 12V

3-6

VCR ELECTRICAL TROUBLESHOOTING GUIDE

NO 8V.

Check or Replace
D110.

Is Vcc(13V) supplied to
(+) terminal in D114?

Is Q162 Base “H”?

Is Vcc(12V) supplied
to IC151 Pin1?

NO

NO

Check or Replace
D114.

NO

Check the Power
Control.

YES

YES

Check or Replace
IC151, R170, C154.

YES

(8) No 8V(TO DVD)

NO 3.3V.

Is Vcc(4V) supplied
to IC152 Pin1?

Is the Q162 Base
“H”?

YES

Check or Replace
IC152, R156, C153.

YES

(9) No 3.3V(TO DVD)

Check or Replace
D111.

NO

NO

Check the Power
Control.

3-7

2. SYSTEM/KEY CIRCUIT

(1) AUTO STOP

(2) The unstable loading of a Cassette tape

Auto Stop

Does the SW30 waveform
appear at IC501 Pin18?

Do the T-UP Reel Pulses
appear at IC501 Pin80?

Is 12V applied to PMC01
Pin8?

Check the Drum Motor
signal.

Does 5V appear at the
RS501?

Check the Q160 Power
Circuit.

Refer to “SMPS DRUM
12 Volt Trouble Shooting”.

Is 5V applied to R531 ?

Refer to SMPS 5.3VA
troubleshooting.

Check IC501
Pins22, 23, 24, 25.

Do T/UP Reel Pulses
appear at the point
between R556 and R536?

Replace the T/UP Reel
Sensor (RS501).

Check the CST SW and
the peripheral circuitry.

Replace the IC501.

The unstable loading of a
Cassette tape

Does the “H” signal appear
at IC501 Pin60 during
inserting the CST ?

Does the “L” signal appear
at IC501 Pin19 during
inserting the CST?

Check the Deck
Mechanism.

Note :

Auto stop can occur because Grease or Oil has dried up

YES

YES

NO

YES

YES

YES

NO

NO

NO

NO

NO

NO NO

YES

YES YES

VCR ELECTRICAL TROUBLESHOOTING GUIDE

3-8

3. SERVO CIRCUIT

(1) Unstable Video in PB MODE

Does the Noise level of the
screen change
periodically?

Do the CTL pulses appear
at IC501 Pin97?

Is the height adjustment of

the CTL Head accurate?

Readjust the height of the
CTL Head.

Replace IC501.

Refer to “When the Y signal
doesn’t appear on the
screen in PB Mode”.

Confirm the CFG
waveform at IC501 Pin87?

On tracking do the CTL
pulses move?

Does the Video Envelope
waveform appear at IC501
Pin9?

Replace IC501.

YES

YES

YES

NO

YES

NO

NO

NO

(2) When the Drum Motor

(2) doesn’t run.

Do the DFG Pulses appear
at PMC01 Pin11?

Replace the Cap M.

Are the foil patterns and
the Components between
IC501 Pin 90 and PMC01
Pin11 shorted?

Replace IC501.

Refer to “(2)
No 12VA of Power section”

Do the Drum PWM Pulses
appear at IC501 Pin76?

Are the foil patterns and
the Components between
IC501 Pin76 and PMC01
Pin12 shorted?

Do the DFG Pulses appear
at IC501 Pin90?

Do the Drum PWM Pulses
appear at IC501 Pin76?

Are the connecting patterns and the Components
between IC501 Pin76 and PMC01 Pin12 shorted?

When the Drum Motor
doesn’t run,

Does 12V appear at
PMC01 Pin8?

Does 2.8V appear at
PMC01 Pin12?

Check the connector
(PMC01) and the Drum
Motor Ass’y.

NO

YES

YES

YES

NO

NO

NO

NO

NO

YES

YES

YES

VCR ELECTRICAL TROUBLESHOOTING GUIDE

3-9

Does the CFG signal appear at
PMC01 Pin1?

Does the PWM signal appear at IC501
Pin77?

Does 2.8V appear at PMC01?

Check the PMC01 and the Capstan
Motor Ass’y.

Does the Capstan PWM signal appear at
IC501 Pin77?

Are the foil patterns and Components
between IC501 Pin77 and PMC01
Pin9 shorted?

Does the CFG signal come into IC501
Pin87?

Are the foil patterns and Components
between IC501 Pin77 and PMC01
Pin9 shorted?

2. SERVO CIRCUIT

(3) When the Capstan Motor doesn’t run,

NO

NO

NO

YES

YES

YES

When the Capstan Motor doesn’t run,

Does 12VA appear at PMC01?

YES

Replace IC501.

YES

NO

NO

YES

Refer to “SMPS(CAPSTAN/12Volt)
Trouble Shooting”.

Are the foil patterns and component
between IC501 Pin87 and PMC01
Pin1 shorted?

Check the Capstan Motor Ass’y.

NO

VCR ELECTRICAL TROUBLESHOOTING GUIDE

3-10

4. OSD CIRCUIT

(1) No OSD display.

(2) I

2

C BUS CHECK

Keys do not work

Is 5V applied to IC501
Pin79?

Does LED or FLD change
when a function button is
pressed?

No OSD or F.OSD display.

Is 5.3V applied to IC501
Pin53?

Does oscillation occur at
IC501 Pins44, 45?

Replace IC501.

No I2C bus communication

Does Power appear at the
Pull up impedence
(R569, R507)?

Replace IC501.

Refer to “SMPS 5.3VA
Trouble Shooting”.

Replace the defective
switches.

Refer to “SMPS 5.3VA
Trouble Shooting”.

Check or Replace the phe­ripheral Circurity.(L511,
R518, C596, C595)

Refer to “SMPS 5.3VA
Trouble Shooting”.

YES

YES

YES

YES

NO

NO

NO

NO

NO

2. SERVO CIRCUIT

(4) Keys do not work

VCR ELECTRICAL TROUBLESHOOTING GUIDE

3-11

5. Y/C CIRCUIT

(1) No Video in EE Mode,

No Video in EE Mode

Does the Video signal
appear at IC302
Pins1, 5?

Is there 5V at IC302 Pin6?

Check the REG 5V Line.
(Power Circuit)

Replace IC302.

Does the Video signal
appear at IC301
Pins28, 30, 32?

Is REG 5.0V applied to
IC301Pins23, 44, 45, 52, 68,
77?

Does the Video signal
appear at IC301 Pin26?

Does the Video signal
appear at IC501 Pin52?

Does the Video signal
appear at IC602 Pin7?

Check the REG 5V Line.
(Power Circuit)

Is I2C BUS signal applied to
IC301 Pins53, 54, 55?

Replace IC301.

Check the path of the sig­nal between IC301 Pin 26
and IC501 Pins50, 52.

Is there 5V on the plus
terminal of C614?

Check the REG 5V Line.
(Power Circuit)

Replace IC602.

Check the System Circuit.
(Refer to ‘SYSTEM I2C BUS
CHECK Trouble Shooting’)

YES

YES

YES

YES

YES

YES

NO

NO

NO

NO

NO

NO

Check the REG 5V Line.
(Power Circuit)

NO

NO

YES

YES

Check DVD Video Input
(IC802, Pin29), Tuner
Video Input (TU701 Pin24),
Line Video Input (JK801),
respectively.

NO

NO

VCR ELECTRICAL TROUBLESHOOTING GUIDE

3-12

3. Y/C CIRCUIT

(2) When the Y(Luminance) signal doesn’t appear on the screen in PB Mode,

Is 5V applied to IC301
Pins23, 44, 45, 52, 68, 77?

Is the Y/C Bus siganl
applied to IC301 Pins53,
54, 55?

Does the normal RF signal
appear at IC301 Pin 14?

Check the line of the REG
5V Line. (Power Circuit)

Check the System Circuit.
(IC501 Pin18)

Check the V.H.S/W level.

Refer to ‘SYSTEM Y/C
BUS CHECK Trouble
Shooting’.

Is the V.H.S/W signal
applied to IC301 Pin57?

Does the Rectangular
waveform(5V) appear at
IC301 Pin57(V.H.S/W)

Clean the Drum.

Check C324.

Check R328, C322, C323.

Does the Y(Luminance)
signal appear at IC301
Pin20?

Is the Y(Luminance) Video
waveform showed up at
IC301 Pin22?

Replace IC301.

NO

YES

YES

YES

YES

YES

YES

YES

NO

NO

NO

NO

NO

NO

VCR ELECTRICAL TROUBLESHOOTING GUIDE

3-13

3. Y/C CIRCUIT

(3) When the C(Color) signal doesn’t appear on the screen in PB Mode,

Is 5V applied to IC301
Pins23, 44, 45, 52, 68, 77?

Does the Color signal
appear at IC301
Pins41, 50?

Check the line of the REG
5V Line. (Power Circuit)

Replace X301.

Check C342, C341,
R333.

Is X301 (3.58MHz)
normal?

Replace IC301.

Does the Color signal
appear at IC301 Pin48?

Replace IC301.

NO

YES

YES

YES

NO

NO

NO

VCR ELECTRICAL TROUBLESHOOTING GUIDE

3-14

3. Y/C CIRCUIT

(4) When the Video signal doesn’t appear on the screen in REC Mode,

YES

YES

NO

NO

YES

YES

YES

YES

YES

Check system part
(V.H/SW)

Replace the IC301.

Check the drum

*OPTION
Pins72, 73, 74(SP)
Pins65, 66, 67(EP)

REC mode

Check the EE mode

NO

Is EE mode normal?

Is color

normal?

A

A

YES YES

Is brightness normal?

Does signal appear at
IC301 Pins41, 50?

NO

Check X301 oscillation
frequency.

YES

Is the brightness signal sup­plied to IC301 Pins18?

Is 5V supplied to IC301
Pins23, 44, 45, 68, 77?

Check the power of Pins23,
44, 45, 52, 68, 77.

Check the 5V power

NO

NO

NO

NO

NO

Is Y/C Bus applied to
IC301 Pins53, 54, 55?

Check the REG 5V power

Check system part

Do X301 and X-TAL
oscillate?

Check X301, 302

Is V.H SW supplied to
IC301 Pin57?

Does the FM signal appear
at IC301*?

VCR ELECTRICAL TROUBLESHOOTING GUIDE

3-15

6. Hi-Fi CIRCUIT

(1) No Sound(EE Mode)

No Sound.

Check the SIF.IN of IC801 Pins57.

Check the DVD Audio of IC801
Pins12, 74.

Check the AV1 Audio of IC801
Pins11, 73.

Check the AV2 Audio of IC801
Pins9, 71.

Check the Vcc of IC801 Pins3, 5, 15,
32, 36, 46, 54.

YES

Check the IIC Clock and DATA at
IC801 Pins37, 38.

YES

Check Audio of IC801 Pins78, 80.

YES

Check Audio of C804, C854.

YES

Check JK601.

Check the TU701 SIF Pin13.

NO

Check the DVD MODULE.
(PMD02 Pins9, 11).

NO

Check the Rear Jack.
(JK601 Audio in).

NO

Check the front Jack.
(JK5L1 Audio in).

NO

Check the Power 5.2V, 5.3VA, REG 9V.
Q701, PMP01 Pins1, 2, 5, 6.

YES

NO

Check IC501 Pins71, 72.

NO

Replace IC801.

Replace C804, C854.

NO

NO

VCR ELECTRICAL TROUBLESHOOTING GUIDE

3-16

3. Y/C CIRCUIT

(2) Hi-Fi Playback

YES

YES

YES

No Sound.

Check the Vcc of IC801
(Pins3, 5, 15, 32, 36, 46, 54).

Check the Hi-Fi Selection switch.
(IC801 Pin39) and the Tape quality.

Is the RF Envelope at
IC801 Pin23 over 3Vp-p?

YES

Check IC801 Pin37(Data),
Pin38(Clock)

YES

Do Audio Signals appear at
IC801 Pin80(L-CH), 78(R-CH)?

YES

Do Audio Signals appear at
JK601?

Check Power.

NO

Check IC501 Pin19
(A.H/SW)

NO

NO

Check the parts of µ-COM
(IC501 Pins71, 72)

NO

Check the Connection at
P3D01 Pins7, 9.

NO

Check the Jack(JK801)

NO

Check C801, C851, R801,
R851.

VCR ELECTRICAL TROUBLESHOOTING GUIDE

3-17

(3) Hi-Fi REC

No recorded Hi-Fi Audio Signal

Check Vcc of IC801.
(Pins3, 5, 15, 32, 36, 46, 54)

Check IC801 Pin37(Data), Pin38(CLOCK).

YES

Do Audio signals appear at IC801 Pin6?

YES

Do Audio signals appear at IC301
Pin76(Normal Audio)?

YES

Do OSC signals appear at P3D02 pins4,5
(50Vp-p)

YES

YES

Check Power.

NO

Check ports of µ-CPM.
(IC501 Pins71, 72)

Check Audio input signal of IC801
Pin57(TU.A.), 7, 69(DVD.A.),
11, 73(AVI.A.), 9, 71(AV2.A.)

NO

Check C825, C306, R311, R312, R346.

Check REC OSC BLOCK
(FL301, Q301~Q305, Q308, Q309)

Is IC501 Pin74 “ High” in REC mode?

NO

NO

NO

VCR ELECTRICAL TROUBLESHOOTING GUIDE

3-18

7. Tuner/IF CIRCUIT

(1) No Picture on the TV screen

No picture on the TV
screen

Does the Video signal
appear at TU701 Pin16.

YES YES

Is +33V applied to TU701
Pin14?

YES

Is +5V applied to TU701
Pin3?

NO

Does the video signal
appear at IC302 Pin7.

NO

Does the Video signal
appear at IC501 Pin 52.

YES

NO

Does the Video signal
appear at IC602 Pin 7.

YES

NO

Check the signal flow from IC602
Pin7 to JK601 Pin Video out.

YES

Check 33V line.

NO

Check 5V line.

NO

YES

Does the Clock signal
appear at TU701 Pin9?

Check the l2C Clock Signal
of µ-COM Pin71.

NO

YES

Does the data signal
appear at TU701 Pin10?

Replace Tuner.

Check the signal flow from
IC501 Pin27.(Pin27 is ‘L’
state in Tuner Mode)

Check the signal from IC301
Pin26 to IC501 Pin50.

Check the signal from IC501 Pin52 to IC602 Pin1 and IC602 Pin2.
(IC602 Pin2 is ‘L’ state in VHS mode)

Check the l2C Data Signal
of µ-COM Pin72.

NO

VCR ELECTRICAL TROUBLESHOOTING GUIDE

3-19

(2) No Sound

No Sound.

Check the Vcc of TU701 Pins3, 14. Check 5.2V, 33V Line.

NO

Check the Tuner SiF signal at IC801
Pin57.

YES

Check the Audio of IC801 Pins78, 80.

YES

Check the Signal flow from IC801 Pins78,
80 to JK601 Audio out(L), (R)

YES

Check the Tuner SIF of TU701 Pin13.

NO

1. Check the Vcc(5.3VA, 9V) of IC801
Pins3, 5, 36, 54.

2. Check the I2C Clock and Data at IC801
Pins37, 38.

NO

VCR ELECTRICAL TROUBLESHOOTING GUIDE

4

3

12

TO CAP MOT

12VA

TO SYS

-27VA

TO SYS

FD(+)

TO SYS

FD(-)

TO DRUM MOT

12VA

TO DVD/Hi-Fi

REG 12V

TO DVD

8V

TO DVD

3.3V

TO TUNER

33V

TO SYS/Hi-Fi/Tu

5.0V

TO DVD

5V

FROM µ-COM

PWR CTL 'H'

TO SYS/Hi-Fi/Tu

5.3VA

DRIVE & S/W BLOCK

OVER CURRENT LIMIT

BLOCK

(IC101,BD01,D102,R105,

C108,R107,C107,C109)

LINE FILTER

BLOCK

(C101, L102, C102)

BD101

C103

V101

1

2

218

17

16

15

14

13

12

11

5

8

3

10

4

3

IC102

D117

T/W

D115

IC103

PW101

BR

(BK)

HOT CIRCUIT

BL

(WH)

F101

F102

C111

HOT GND

R101

SNUBBER

BLOCK

(D101, R104,

C105, C106)

RECTIFIER &
SMOOTHING

(D110, C123, L122,

C126, C163)

RECTIFIER &
SMOOTHING

(D108, C130, R118)

RECTIFIER &
SMOOTHING

(D111, C127,
L123, C128)

RECTIFIER &
SMOOTHING

(D112, L124,
C129, C131)

FEED-BACK

BLOCK

(R112, R113, C133,

R114, R115, R116,

R117)

8VA REG

BLOCK

(D114, IC151, C154)

12VA REG

BLOCK

(Q156,ZD103,C151,

C152,R153)

3.3V REG
BLOCK

(IC152, C153)

RECTIFIER &
SMOOTHING

(D113, R119, C132)

33V S/W

BLOCK

(Q114, R154, R155)

PWR CTL

BLOCK

(Q162,R163,R164,

R171,C161)

5V BLOCK

(R157, Q160, R158,

R159, D121, C155)

!

!

C110

! !

!

!

NOTES : Symbol denotes AC ground.

Symbol denotes DC chassis ground.

RECTIFIER &
SMOOTHING

(D107, C121,

ZD101, R167, R168)

3-20 3-21

BLOCK DIAGRAMS

1. POWER(SMPS) BLOCK DIAGRAM

5.3VA

5.0V

GND

CAP VCC

REG 12V

33V

DRUM VCC

PWR CTL 'H'

GND

HSR 'H'

GND

GND

FD(-)

FD(+)

-27VA

PMP01-PPM01

123456789

1011121314

15

A.IN

CH S/W

REG 5V

CONTROL

V.IN

RF AGC

NC

ENABLE

CLOCK

DATA

AFT

A.OUT

SIF

TU 30V

NC

V.OUT

999 GND

83 PWR CTL 'H'

81 HSR 'H'

110 FD(-)

109 FD(+)

108 -27VA

100AFT

732TU.V.OUT

103 DRUM VCC

102 REG 12V

104 CAP VCC

107 REG 5V

786 REG 9V

875 MOD A.IN

61 MOD CTL

106 5.0V

26 VCR 'H'

671 MOD V.IN

71 IIC CLK

72 IIC DATA

781 SIF OUT

1

2

3

4

5

6

7

8

9

10

11

12

13

14

15

16

REG. BLOCK

5V

REG. BLOCK

9V

3-22 3-23

2. TU/IF BLOCK DIAGRAM