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

Model Series:

CONTENTS

XBV323

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

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

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

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

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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

284

283

LD601

300

330

276

260

A46

A46A

A48

A00

A26

285

457

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

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

PDP01PPD01

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

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

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

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

Replace BD101.

Replace R101.

Is D102 normal?

Check or Replace D102.

Replace D112.

Replace IC103.

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

Replace D115.

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

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

Check the Power Control.

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

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

Check or Replace D114.

NO

Check the Power Control.

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

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

NO

YES

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

NO

YES

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

NO

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

YES

When the Capstan Motor doesn’t run,

Does 12VA appear at PMC01?

YES

Replace IC501.

YES

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

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

NO

Check the REG 5V Line. (Power Circuit)

NO

YES

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

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

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

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

NO

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

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

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

VCR ELECTRICAL TROUBLESHOOTING GUIDE

3-16

3. Y/C CIRCUIT

(2) Hi-Fi Playback

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

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

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

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

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

3-24 3-25

3. Y/C BLOCK DIAGRAM

EP PB 'A'

EP PB 'B'

SP PB 'B'

SP PB 'A'

64

59 58 57 55 54 53

65

67

72

74

ACC

DET

ENV DET

C-ROT RF-SW IN

Y/C ENA

Y/C DATA

Y/C CLOCK

V.OUT

AUDIO

MUTE

HA SW

P

C-LPF

MAIN

CONV

3.58M BPF2

ACC

AMP

ACC DET

CLAMP

Y

LPF

CLAMP

IN

OUT

VCA

CCD

3.58M BPF1

Y/C MIX

6dB

DOUBLE

LIMFMDEM

SUB LPF

MAIN

DE-EM

PB

FM-EQ

FM

AGC

CNC

YNR

COMB

4.21M BPF

SUB

CONV

39

37

36

34

26

22

21

P

B

(PB Mode)

EP REC

SP REC

57

V. H/SW55Y/C ENA

54

Y/C DATA

53 51 50 49 48 47

39

38

37

36

34

32

30

28

22

21

20

73

70

69

66

Y/C CLOCK

X-TAL

3.58MHZ

C-LPF

MAIN

CONV

4.21M BPF

SUB

CONV

DETAIL

ENH

MAIN

EMPHA

REC

FM-EQ

4.7K

FM

MOD

Y

LPF

YNR

COMB

3.58M BPF1

LINE2

26

V.OUT

DVD

TU/LINE1

VIDEO

AGC

CLAMP

IN

CCD

OUT

VCA

SW

BLOCK

IC302

NL

EMPHA

B-UP AMP

ACC AMP

ACC

DET

BGA

REC APC

320FH

VCO

SLDVX01

SERIAL

DECODER

R

B

(REC Mode)

3-26 3-27

4. NORMAL AUDIO BLOCK DIAGRAM

IC301

LA71206M

SIF

A_IN

RF_MOD

IC801

LA72670M

TUNER

TU701

10

76

DET

NORMAL

AUDIO

OUT

LINE AUDIO(R) IN

LINE AUDIO(L) IN

REAR Jack

A. OUT (L)

ALC

4

6

13

1

57

9

2

71

80

78

A. OUT (R)

(System)

IC801

LA72670M

IC301

LA71206M

AMP

EQ

AMP

78

410

A. OUT (R)

MOD. OUT

DATA

CLOCK

R/P HEAD

N.A.IN

53

ENA

55 54

5

4

6

From u-COM

80

A. OUT (L)

2

OUTPUT

SELECTOR

EQ

3

2

IC301

LA71206M

SIF

IC801

LA72670M

TUNER

TU701

10

76

DET

NORMAL

AUDIO

OUT

LINE AUDIO(R) IN

LINE AUDIO(L) IN

REAR Jack

A. OUT (L)

REC

AMP

4

6

13 57

RF MOD.

A_IN

1 2

9

71

80

78

A. OUT (R)

ALC

9

(EE Mode) (PB Mode) (REC Mode)

A

B

Hi-Fi/

REC

IC801

LA72670M

A.OUT

To JACK

MODULATOR

A.OUT (To Tu)

24

Hi-Fi PB 'B'

Hi-Fi PB 'A'

Hi-Fi REC

57

12

74

11

73

9

71

6 4

26 27

80

A.OUT 'L'

A.OUT 'R'

78

3

AUDIO INPUT

BLOCK

NORMAL AUDIO

OUT(To AVCP)

NORMAL AUDIO

IN(From AVCP)

SIF

DVD A.IN 'L'

DVD A.IN 'R'

AV1 A.IN 'L'

AV1 A.IN 'R'

AV2 A.IN 'L'

AV2 A.IN 'R'

3-28 3-29

5. Hi-Fi BLOCK DIAGRAM

GND

MODE S1 MODE S2 MODE S3 MODE S4

MODE S/W

TO/FROM AVCP

T-UP REEL

T-UP END

SUP REEL

CST.SW/REC TAP

5V

CS501

5.3VA

ES501

R550

LD501 DECK IR LED

R553

R555

RS501

RS502

R556

R558 C582

R538

R535

R537

R536

C534

R544

C552

R5C6

C500 C517

R541

R529

R583

L512

MS501

X502

14MHz

32.768KHz

OSC

X501

1

2

RESET

GND

Vcc

3

5.3VA

5V

IC504

+

+ +

C592

+

C503

L501

R557

SUP END

ES502

C535

R564

R531

OSC

R/C

RC601

L511 R598 C595 C596

+

C561

TO/FROM DECK

Q503

Q501

CV IN

25

24

23

22

21

79

58

80

88

49

40

37

98

34

IC501

M37760

MODE S1

I-Limit

MODE S2

MODE S3

MODE S4

T-UP Sensor

T-UP Reel

SUP Reel

CST IN

Vss (AMP)

Vss (OSD)

Vss (SYSCON)

Vcc

(SYSCON)

Vcc

(SERVO)

CAP. PWM

CTL +

CTL -

CFG

CAP. REV 'H'

LD CTL

V. ENV

V.H.SW30

DPG

D.V.Sync

38

39

X out

Xc in

Xc out

X in

35

36

44

OSC in 2

95

94

87

12

59

9

18

76

90

13

H.A.SW

SQPB

16

59

77

11

DRUM PWM

53

Vcc (OSD)

20

SUP Sensor

45

OSC out 2

14

99

Vcc (A/D)

TO/FROM AUDIO(Hi-Fi)

TO/ FROM TU/IF

72

100

26

VCR 'H'

PLL DATA

PLL CLK

CV OUT

AFT

71

52

POWER FAIL

78

A. MUTE 'H'

A. ENV

A. H.SW

REC 'H'

74

68

71

72

CLK

DATA

74

50

COMP IN

17

REC 'H'

15

C.ROT

84

A.MUTE'H'

S clk

S in

S out

8

19

67

66

65

Hi-Fi ONLY

2

GND

Vcc

3

IC505

1

IC5F1

DISPLAY

3-30 3-31

6. SYSTEM BLOCK DIAGRAM

NOTES) Symbol denotes AC ground.

NOTES) Symbol denotes DC chassis ground.

NOTE) Warning

NOTE) Parts that are shaded are critical NOTE) With respect to risk of fire or NOTE) electricial shock.

3-32 3-33

CIRCUIT DIAGRAMS

1. POWER(SMPS) CIRCUIT DIAGRAM

Switching Error. IC101 is defective.

Switching Error. IC103, 102 are defective.

2.5V, 3.3V no power. D111 is defective.

No Power. F101 is defective.

5.3VA no power. D112 is defective.

33V no power. D113 is defective.

No power. BD101, R101 are defective.

12VA no power. D110 is defective.

IMPORTANT SAFETY NOTICE

WHEN SERVICING THIS CHASSIS, UNDER NO CIRCUMSTANCES SHOULD THE ORIGINAL DESIGN BE MODIFIED OR ALTERED WITHOUT PERMISSION FROM THE ZENITH ELECTRONICS CORPORATION. ALL COMPONENTS SHOULD BE REPLACED ONLY WITH TYPES IDENTICAL TO THOSE IN THE ORIGI-

NAL CIRCUIT. SPECIAL COMPONENTS ARE SHADED ON THE SCHEMATIC FOR EASY IDENTIFICATION.

THIS CIRCUIT DIAGRAM 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 UNTILTHE NEW SERVICE LITERATURE IS PRINTED.

NOTE :

1. Shaded( ) parts are critical for safety. Replace only with specified part number.

2. Voltages are DC-measured with a digital voltmeter during Play mode.

PB

REC

3-34 3-35

2. TU/IF CIRCUIT DIAGRAM

3

1

7

8

9

1

4

5

2

6

PB Y+C

REC Y+C

WAVEFORM

3-36 3-37

3. A/V CIRCUIT DIAGRAM

IC301 Pin 59 is defective.

Auto Tracking has failed.

IC301 Pin 57 is defective.

PB COLOR Signal does not appear.

IC301 Pins 53, 54, 55 are defective.

IC301 doesn’t operate.

IC301 is defective.

PB COLOR Signal does not appear.

IC306, Q307 are defective.

EE, PB Screen doesn’t appear.

FL301, Q304, Q305 are defective.

Normal Audio Signal is not recorded.

PB

REC

100

T/W

KTC3875

'02. 12. 04 R13734C

3-38 3-39

4. Hi-Fi CIRCUIT DIAGRAM

No Hi Fi Audio 23 Pin is defective.

No Audio IC801 Pins37, 38 aredefective.

ONLY COMPONENT OPTION

ONLY SVHS OPTION

3-40 3-41

5. JACK CIRCUIT DIAGRAM

1

3

48 5 6

7

2

WAVEFORM

0

R545

0

14 504

1K

C542 680P

MTZ5.6B

5 6 7 8

4 3 2 1

R502

100

72 71 99

R501

100

IC501

M37762

IC503

'02. 12. 04 R13732C

FROM TO JACK

EEPROM

29

28

VCR LCD DVD LED NC

3-42 3-43

6. SYSTEM CIRCUIT DIAGRAM

Q501, Q503 are defective.

µ-COM is unstable.

IC505 is defective.

VCR will not operate.

X501 is defective.

CLOCK SETTING will not operate.

X502 is defective.

µ-COM will not operate.

IC504 is defective.

• Reset is defective.

• Set dead.

ES501, ES502, LD501 are defective.

Auto Rew will not work.

RS501,RS502 are defective.

Auto stop occures.

R575, R576, R577, R578 are defective.

Deck will not operate.

3-44 3-45

7. TIMER CIRCUIT DIAGRAM

3-46 3-47

• WAVEFORMS

* IC301 Waveform

IC301 Pins 20, 21, 22 100mV/10msec DIV VV/EE

20 Main DE Emphasis Filter 21 Main DE Emphasis out 22 Clamp in

IC301 Pin 32 200mV/10msec DIV EE (VIDEO IN)

IC301 Pin 41 100mV/0.2msec DIV REC/PB (2fsc)

IC301 Pin 25

1.0V/20msec DIV VV/EE (C-SYNC OUT)

IC301 Pin 49 100mV/0.2msec DIV PB/REC (3.58MHz X-TAL IN)

IC301 Pin 14 100mV/5msec DIV PB (PB RF out)

IC301 Pin 73 500mV/2msec DIV SP REC (REC RF)

IC301 Pin 26 500mV/10msec DIV VV/EE (VIDEO OUT)

IC301 Pin 66 500mV/2msec DIV EP REC (REC RF)

* IC501 Waveform

Tek Stop : 10.0KS/s

280 Acqs

M5.00ms Ch1Ch1 3.04 V1.00 V

T

1

Tek Stop : 250KS/s

299 Acqs

M 200µs Ch1Ch1 3.04 V1.00 V

T

1

Tek Stop : 10.0KS/s

18 Acqs

M 5.00ms

Ch1

3.04 V

Trigger Position: 12%

1.00 V

T

1

T

Tek Stop : 10.0KS/s

27 Acqs

M5.00ms Ch1Ch1 3.04 V1.00 V

T

1

Tek Stop : 10.0KS/s

35 Acqs

M5.00ms Ch1

Ch1

3.04 V1.00 V

T

1

Tek Stop : 50.0KS/s

120 Acqs

M1.00ms Ch1Ch1 3.04 V1.00 V

T

1

T

Tek Stop : 5.00KS/s

2 Acqs

M 10.00ms

Ch1

340V

Trigger Level: 340mv

500mV

T

1

IC501 Pin 18 REC/PB

IC501 Pin 13 QUE/REV

IC501 Pin 95 REC

IC501 Pin 87 REC/PB

IC501 Pin 90 REC/PB (DPG/DFG)

(DPG)

(DFG)

IC501 Pin 97 PB (CTL OUT)

IC501 Pin 94 REC

3-48 3-49

• CIRCUIT VOLTAGE CHART

EE PLAY

MODE

PIN NO.

2.3

2.29

2.31

2.3

0

2.31

2.25

4.93

1

0.97

1.92

1.55

0

2.37

2.39

0

2.46

1.73

3.07

4.96

0

0.36

1.83

1.47

2.25

2.32

2.25

4.08

2.25

3.62

2.97

3.13

2.37

2.35

0

1.82

0

0.83

2.34

0

4.92

4.95

2.27

3.31

3.32

3.94

2.54

2.12

4.95

4.75

4.7

2.31

2.28

2.29

2.31

2.32

2.31

2.27

4.93

1

0.97

1.89

1.53

0

2.55

1.45

0

2.49

1.79

2.29

4.95

0

0.35

1.87

1.6

2.56

2.31

2.26

4.08

2.26

2.8

2.93

3.14

2.37

2.29

0

1.87

0

0.83

2.37

0

4.92

4.95

3.17

3.31

3.32

3.94

2.55

2.09

4.95

4.62

4.52

EE PLAY

MODE

PIN NO.

0.68

0

4.91

2.92

0

3.96

1.76

1.84

4.93

0.18

0.15

0

1.82

0

2.3

4.96

2.3

0

2.3

2.96

0

3.01

5.12

2.95

4.97

2.2

0

0.97

5.17

0

0.5

0

0.4

0.19

0.29

0.68

0

4.78

0

0.68

2.56

2.57

0.93

0

2.56

1.61

2.9

0.94

1.94

0

3.98

1.72

1.85

1.86

4.93

0

0.71

0

2.3

4.96

2.3

0

2.3

2.96

0

3

5.12

2.95

4.97

2.2

0

5.17

5.16

0

0.54

0

0.42

4.06

3.91

0.99

3.42

0

4.78

2.57

0

0.43

2.57

IC302

IC501

EE PLAY

MODE

PIN NO.

0

0.11

5.17

]5.17

5.17

0

5.13

0

5.15

1.52

1.43

5.15

2.19

2.28

0

0.51

0.26

2.35

2.41

0

1.29

0

1.88

0.53

1.88

4.96

2.03

2.6

1.96

0

2.57

0

0.97

2.38

5.07

4.7

5.02

4.75

5.17

0

0.11

5.17

0

5.13

5.17

5.13

0

5.15

1.51

1.44

5.15

2.18

2.27

0

0.55

0

2.34

2.41

0

1.99

0.57

1.98

4.95

2.03

1.92

2.05

0

2.58

4.28

0

0.86

0

5.07

4.45

4.97

4.61

5.17

0

EE PLAY

MODE

PIN NO.

0

4.94

5.03

0

2.69

0.58

0.17

0

0.54

0.1

2.53

2.54

0.21

2.5

2.52

5.08

5.17

2.64

5.19

0

5.14

5.19

0

4.7

1.93

2.01

5.05

1.7

0

5.05

2.51

0

2.27

0

5.06

2.53

0

2.56

9.21

2.48

0

1.79

2.72

4.76

0

4.94

4.98

0

2.67

0.68

2.36

0

1.36

2.54

2.53

0

2.49

2.52

5.08

5.17

1.95

5.19

0

5.14

5.19

0

4.7

1.93

2.01

5.05

1.7

0

5.05

2

0

2.35

0

5.06

2.04

0

2.54

9.18

2.48

IC504

IC505

IC601

IC602

IC801

EE PLAY

MODE

PIN NO.

5

6

7

8

9

10

11

12

13

14

15

16

17

18

19

20

21

22

23

24

25

26

27

28

29

30

31

32

33

34

35

36

37

38

39

40

41

42

43

44

45

46

47

48

49

50

51

52

53

54

55

56

57

58

59

5.19

1.91

0

0.29

0

2.5

1.91

2.49

5.06

2.51

0

2.51

2.52

2.51

0.19

2.25

0

2.24

2.25

0

2.48

0

2.51

5.02

2.64

0

5.06

5.17

0

0.19

2.52

2.51

2.52

0

5.06

2.49

1.9

0

2.05

1.22

3.86

9.2

6.26

1.96

2.2

4.56

2.52

5.19

2.07

0

1.31

0

2.5

2.44

2.49

5.05

2.51

0

0.86

2.44

2.45

2.43

2.42

3.66

2.3

0

2.3

0

0.11

1.34

3.79

5.01

2.65

2.64

0

5.05

5.17

2.57

0

2.45

2.43

2.45

0.25

5.05

2.49

2.42

0

2.06

0

0.25

9.19

0.28

0.29

2.15

0

2.35

EE PLAY

MODE

PIN NO.

3.86

3.15

4.02

3.83

2.45

3.87

4.09

3.88

3.94

0

3.86

0

2.5

3.87

3.17

0

4.42

0

4.4

5.06

0

0.1

0.13

0

0.76

0

0.23

0.24

0

0.32

0.31

0

0.31

0

2.5

0.4

0.22

0

4.3

0

4.3

5.07

0

0.73

0

0.26

0.77

0.76

0

SW601

IC301

1

2

3

4

5

6

7

8

9

10

11

12

13

14

15

16

17

18

19

20

21

22

23

24

25

26

27

28

29

30

31

32

33

34

35

36

37

38

39

40

41

42

43

44

45

46

47

48

49

50

51

52

53

54

55

56

57

58

59

60

61

62

63

64

65

66

67

68

69

70

71

72

73

74

75

76

77

78

79

80

1

2

3

4

5

6

7

8

1

2

3

4

5

6

7

8

9

10

11

12

13

14

15

16

17

18

19

20

21

22

23

24

25

26

27

28

29

30

31

32

33

34

35

36

37

38

39

40

41

42

43

44

45

46

47

48

49

50

51

52

53

54

55

56

57

58

59

60

61

62

63

64

65

66

67

68

69

70

71

72

73

74

75

76

77

78

79

80

81

82

83

84

85

86

87

88

89

90

91

92

93

94

95

96

97

98

99

100

1

2

3

1

2

3

1

2

3

4

5

6

1

2

3

4

5

6

7

8

1

2

3

4

60

61

62

63

64

65

66

67

68

69

70

71

72

73

74

75

76

77

78

79

80

1

2

3

4

5

6

7

8

9

10

11

12

EE PB EE PB

Base Emitter Collector

PB EE

Location

No.

Q301

Q302

Q303

Q304

Q305

Q306

Q307

Q308

Q309

Q501

Q503

Q504

Q505

Q506

Q507

Q805

Q701

Q702

Q601

Q602

4.26

0.758

0.734

0

4.92

1.828

1.843

5.19

0

0.68

5.17

2.82

1.58

5.07

2.8

2.56

9.02

4.98

0.75

4.96

0

4.93

2.5

2.62

4.91

0

4.48

2.27

2.24

0

3.23

2.08

9.81

5.7

0

4.907

0

4.93

4.91

0

5.15

4.95

4.96

0

5.06

12.58

5.19

0

4.91

0

4.92

4.97

0

5.15

4.95

4.96

3.29

0

5.05

12.99

5.19

0

4.26

1.74

0.72

0

4.92

1.86

2.05

5.19

0

0.68

5.17

2.94

1.58

0

2.6

2.56

9.24

4.97

0.75

4.97

0

4.94

2.45

2.51

4.87

0

4.48

2.18

1.03

0

2.08

9.82

5.7

0

LOCATION GUIDE

3-50 3-51

PRINTED CIRCUIT DIAGRAMS

1. VCR P.C.BOARD

3-52 3-53

2. KEY 1(LEFT) P.C.BOARD

LOCATION GUIDE

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

LOCATION GUIDE

3-54 3-55

4. POWER P.C.BOARD

LOCATION GUIDE

NOTES) Warning

NOTES) Parts that are shaded are critical NOTES) With respect to risk of fire or NOTES) electricial shock.

3-56

ELECTRICAL TROUBLESHOOTING GUIDE

1. System operation flow

Power On

No

Yes

No

Show LOGO

Tray Closed?

Tray Close to Closed position

SLED Moves to Inner Position

Recieve

OPEN/ CLOSE

Key?

Receive

CLOSE Key?

1. Stop Playback & Open Tray

2. Display tray open message & LOGO

1. Execute Pressed Key & IR Key

2. Systemoperati on Routi ne Loop

1. Judge whether have disc and disc type

2. Jump to related disc reading procedure

SLED at Inner

Side?

1. 8032 initializes SERVO, DSP & RISC registers

2. Write RISC code to SDRAM

3. Reset RISC

DVD SECTION

3-57

2. Test & debug flow

TEST

Check the POWER PART

No

Yes

No

Yes

No

Yes

Check the POWER PART

Check the regulators or diode(D601).

Check the cable connection. (PDV02)

1. Check 27MHz system clock.

2. Check systemreset circuit.

3. Check FLASH R/Wenable signal PRD, RWR.

4. Check RS232 SIGNALS.

5. Check FLASH Memory related circui t.

Check the

AC Vol tage

Power PCBA (110V

or 220V)

Switch on the Power PCBA

Is

the DC Voltage

outputs OK?

(5V, 3.3V, 8V, 12V)

Is 3.3V and 2.5V DC

outputs normal on main

PCBA?

Update

FLASH(IC5A1)

successfully?

Replace FLASH( IC5A1)

A

Communication between VCR & DVD is normally?

Connect to PC RS232 Cable and update the FLASH memory code.

3-58

A

B

RESET or Power On.

Show LOGO?

Flash

Memory operates

properly?

Check connection lines between FLASH & MT1379 and the FLASH access time whether is sui table or not.

SDRAM

works properl y?

MT1379

VIDEO outputs

properly?

Have

TV signal output?

Check AV cable connection to TV set .

Check the load OPEN & CLOSE switch

Check the Tray control IO pins on MT1376 & MT1379.

Check the Tray control amplifying circuit on Motor driver.(IC202)

Does

Tray move inside

when it is not at

closed position?

Normal

TROUT & TRIN

signals?

Normal

TRCLOSE &

TROPEN signal?

Normal

LOAD+ & LOAD-

signal ?

Check the cable connection between main PCBA and loader. (MECHA)

Check connection lines between SDRAM(IC502,IC503) & MT1379 and the SDRAM is damaged.

Check the related circuit of MT1379. (IC501 PIN 161,166, 168 check)

Check the filtering and amp circuit of TV si gnal .(IC604)

NO NO

NO

YES

3-59

B

No

Yes

OKYes

Yes

No

Yes

No

Yes

No

NoNo

No

Does

the SLED move

to inner side when it is at

outer position?

Motor Driver STBY

Pin is High?

Motor Driver STBY

Pin is High?

SL+ and SL- output

properly?

Optical

Lens has movements

for searching

Focus?

Proper F+

& F- outputs?

Check cable connect of the pick-up head.

Proper FOSO outputs

to motor driver?

Check FOSO connection on MT1379 and motor driver.

Check the amp circuit on motor driver.

C

Check the cable connection with MECHA.

Do not put in disc and tray close.

Check the connection line of STBY signal .

Check the related circuit of FMSO.

Check the amp circuit on motor driver.

3-60

C

No

Yes

No

Laser turns on when

reading disc?

LD01 or LD02 output

properly?

Check the laser power circuit on MT1336 and connecting to power transistor. (Q204, Q205)

Check the related circuit on laser power transi stor

Check the related circuit on MT1336 RFL signal .

Collector voltage of power transistor is OK?

( Q204, Q205)

Check cable connection between transistor output and pick-up head.

Proper RFL signal

on MT1336?

Proper

DMSO signal on

MT1379

Check DMSO related circuit on MT1379.

Check the spindle control amp circuit of motor driver.

SP+ & SP- output

properly?

Check the cable connection between spindle and main PCBA.

Check the RFL connection between MT1336 and MT1379.

Disc ID is correct?

Does spindle rotate?

D

3-61

D

Yes

No No

Yes

No

NoNo

No

Focus ON OK?

Track On OK?

Disc is play?

E

Proper

signals on A, B, C,

D of MT1336

Check connections between MT1336 and pick-up head.

Proper FEO signal

on MT1336?

Proper FEO signal

on MT1336?

Check the related circuit on MT1336 FEO sugnal .

Check the related circuit on MT1336

Properly TRSO signal

on MT1379?

T+ & T- output

properly?

Check the TRSO connection on MT1379 and motor dirver.

Check the tracking control amp circuit on motor driver.

Check cable connection on pick-up head.

Check RF signal waveform.

Check FEO connection between MT1336 and MT1379

3-62

E

NO

YES YES

YES

NO

Normal

Audio output

when disc playback?

TEST END

Audio

DAC received

correct data stream?

Normal

Audio DAC

out? (IC401)

Check Audio filter, amplify, mute circuit. (IC402 Application circuit)?

Check connection between MT1379 & Audio DAC. (Check VRST#, ACLK, ABCK, ASDAT3)

Check the related circuit of Audio DAC. (Check Audio out Pin 14, 15,18,19)

DETAILS AND WAVEFORMS ON SYSTEM TEST AND DEBUGGING

1. SYSTEM 27MHz CLOCK,RESET,FLASH R/W SIGNAL

1) MT1379 main clock is at 27MHz(X501)

3.8V, 27MHz

FIG 1-1

2) MT1379 & MT1336 reset is high active.

PWR_CTL(CN505 PIN 7)

5.2VA

Power Cord in

M_RESET(CN505 PIN 9)

URST(IC501 PIN 188)

FIG 1-2

3-63

3-64

3) RS232 waveform during procedure(Downloading)

TXD(J6 PIN3)

RXD(J6 PIN 2)

FIG 1-3

4) Flash R/W enable signal during download(Downloading)

FRD(IC5A1 PIN 28)

FWR(IC5A1 PIN 11)

FIG 1-4

3-65

2. SDRAM CLOCK

1) MT1379 main clock is at 27MHz(X501)

(IC502,IC503 PIN 35)

DCLK = 93MHz, Vp-p=2.2, Vmax=2.7V

FIG 2-1

3. TRAY OPEN/CLOSE SIGNAL

1) Tray open/close waveform

OPEN((CN203 PIN 3)

CLOSE(CN203 PIN 2)

TROPEN(IC202 PIN 1)

TRCLOSE(IC202 PIN 2)

FIG 3-1

3-66

2) Tray close waveform

OPEN((CN203 PIN 3)

CLOSE(CN203 PIN 2)

TROPEN(IC202 PIN 1)

TRCLOSE(IC202 PIN 2)

FIG 3-2

3) Tray open waveform

OPEN((CN203 PIN 3)

CLOSE(CN203 PIN 2)

TROPEN(IC202 PIN 1)

TRCLOSE(IC202 PIN 2)

FIG 3-3

3-67

4. SLED CONTROL RELATED SIGNAL (NO DISC CONDITION)

FMSO(2.0V/1.4V/1.0V) (IC501 PIN 19)

STBY(5V) – (IC201 PIN 50)

SL+(4.7V/3.6V/1.9V) (IC202 PIN 12)

SL-(5.3V/3.7V/2.5V) (IC202 PIN 13)

FIG 4-1

5. LENS CONTROL RELATED SIGNAL(NO DISC CONDITION)

FOSO(1.5V/1.4V/1.3V) (IC501 PIN 12)

F+(4.0V/3.6V/3.2V) (IC202 PIN 9)

F-(4.0V/3.6V/3.2V) (IC202 PIN 8)

FIG 5-1

3-68

6. LASER POWER CONTROL RELATED SIGNAL(NO DISC CONDITION)

MDI1(0V/180mV) (IC201 PIN 124)

LD01(5.0V//3.5V) IC201 PIN 125)

LD02(5.0V/3.6V) (IC201 PIN 126)

FIG 6-1

7. DISC TYPE JUDGEMENT WAVEFORMS

F+(IC202 PIN 9)

FE(IC201 PIN 18)

RFL(IC201 PIN 19)

FIG 7-1 (DVD)

3-69

F+(IC202 PIN 9)

FE(IC201 PIN 18)

RFL(IC201 PIN 19)

FIG 7-2 (DVD)

F+(IC202 PIN 9)

FE(IC201 PIN 18)

RFL(IC201 PIN 19)

FIG 7-3 (CD)

3-70

F+(IC202 PIN 9)

FE(IC201 PIN 18)

RFL(IC201 PIN 19)

FIG 7-4 (CD)

8. FOCUS ON WAVEFORMS

FE(IC201 PIN 18)

FOSO(IC501 PIN12)

F+(IC202 PIN 9)

F-(IC202 PIN 8)

FIG 8-1 (DVD)

3-71

FE(IC201 PIN 18)

FOSO(IC501 PIN12)

F+(IC202 PIN 9)

F-(IC202 PIN 8)

FIG 8-2 (CD)

9. SPINDLE CONTROL WAVEFORMS (NO DISC CONDITION)

DMSO(1.4V/1.8V) (IC501 PIN 18)

SP-(3.6V/2.4V) (IC202 PIN 10)

SP+(3.6V/4.8V) (IC202 PIN 11)

FIG 9-1

3-72

10. TRACKING CONTROL RELATED SIGNAL(System checking)

TE(IC201 PIN 21)

TRSO(IC501 PIN 13)

T-(IC202 PIN 7)

T+(IC202 PIN 6)

FIG 10-1(DVD)

TE(IC201 PIN 21)

TRSO(IC501 PIN 13)

T-(IC202 PIN 7)

T+(IC202 PIN 6)

FIG 10-2(CD)

3-73

11. RF WAVEFORM

RFOP(2.3V/1.1V) (IC201 PIN 6)

RFON(0.8V/2.0V) (IC201 PIN 7)

FIG 11-1

12. MT1379 AUDIO OPTICAL AND COAXIAL OUTPUT (ASPDIF)

(IC501 PIN 153)

FIG 12-1

3-74

13. MT1379 VIDEO OUTPUT WAVEFORMS

1) Full colorbar signal(CVBS)

(IC604 PIN 23)

FIG 13-1

2) Y

(IC604 PIN 21)

FIG 13-2

3-75

3) C

(IC604 PIN 26)

FIG 13-3

14. AUDIO OUTPUT FROM AUDIO DAC

1) Audio L/R

FIG 14-1

(JK601 PIN 4,5)

3-76

2) Audio related Signal

ASDAT3(IC501 PIN 157)

ABCK(IC501 PIN 148)

ALRCK(IC501 PIN 149)

ASDATA3

FIG 14-2

3-77

BLOCK DIAGRAMS

1. Overall Block Diagram

M

DISC

SPINDLE

MOTOR

LOADING

MOTOR

DECK MECHANISM

DVD:RF0,A,B,C,D

CD:RF0,A,B,C,D,E,F

PICK

UP

KEY Input

B/Pb

IC5A1

29LV800TA-70

1M

8BIT

FLASH ROM

URST

A[00:19]

PCE#

PRD#

PWR#

DQ[00:15]

RFON,RFOP,FEO,RFL,CSO

TEO,BDO,RFRP,HTRC,V2P8

L/R

CVBS

R/Pr G/ Y

Y[1:6]

Y

C

L/R

VF+

AC 90V~240V

50HZ/60Hz

VF-

-27VA

5V

3V3M

12V

STBY,TRCLOSE

27MHz

X-TAL

PWRCTL

DV33

IC505

KS24C021CS

EEPROM

IC401

CS4391(2DAC)

IC401

NJM4580

OP-AMP

RC901

REMOCON

RECEIVER

IC903

RESET IC

LOAD+,LOAD-

F+,F-,T+,T-

SP+,SP-

IC201

MT1336E

RF

SLED

(FEEDING)

MOTOR

SL+,SL-

IC202

LA6560

MOTOR

DRIVER

M

V33

DV33

AV33/DV33/V25

VCC/DV33/3V3M

ACLK

ABCLK

ALRCK

IC604

MM1623XFBE

VIDEO BUFFER

MIC_DETC

ASPDIF

COAX OPTICAL

ASPECT

VCC

RVCC

AVCC

AV33

V25

LD01,LD02, IOA, V2.0

VCC/+8V

RVCC

LIMIT

TROUT,TRIN

TROPEN,TRSO,FOSO,DMSO,FMSO

°‹

SCLK,SDEN,SDATA

PWMOUT2

AD[0:7]

VCC

VCR

VFD_SCK

VFD_TXD

M_REQ

POWER

BOARD

V1P4

MDI1

APC

VFD_RXD

S_REQ

5V2A

+P8V

MUTE

J6

RS232

TXD

RXD

SCL

IC502

M12L16161A

512K

2Banks

16BIT

SDRAM

SD33

IC503

M12L16161A

512K

2Banks

16BIT

SDRAM

SD33

IC506

M12L64164A

1M

4Banks

16BIT

SDRAM

MA[00:10]

BA0

DCLK

DCKE

CS#

RAS#

CAS#

WE#

DQM[0:1]

DQ[16:31]

DQM[2:3]

MA11,BA1

SDA

VRST#

ASDAT[0:3]

VSCK

VSDA

ASTB

IC501

MT1379E

DSP/MPEG

+12V

+12VVCC

DV33

IC510

BUFFER IC

74HCT244

VCC

ADIN

SD33

3-78

IC202

LA6560

Motor Driver

DVD: A,B,C,D, RFO

CD: A,B,C,D, E, F,RFO

SP+, SP-

M/D

PICK

UP

X501

IC501

MT1379

DVDPLAYER

COMBO

CHIP

IC201

MT1336E

RF Signal

Processor

FOSO,TRSO,FMSO

DMSO,,TROPEN

FEO,TEO,RFL,RFRP

BDO,CSO,HTRC,V2P8

ADIN

F+, F-, T+, T-

SL+, SL-

LOAD+, LOAD-

27MHz

X-TAL

RFOP,RFON

LD0 1, LDO 2, IOA

MDI 1

ALPC

V20

SDEN, SDATA,

SCLK,PWMOUT2

LIMIT,TRIN,TROUT

TRCLOSE

STBY,V1P4

IC302

GM72V161621

1M x 16bit

SDRAM

IC303

GM72V161621

1M x 16bit

SDRAM

MA[0:10]

DQM0 ,DQM1

WE#,CAS#,RAS#

CS#,BA0,

DCLK

DCKE

DQ[0:15]

DQ[16:31]

MA[0:10]

DQM0 ,DQM1

WE#,CAS#,RAS#

CS#,BA0,

DCLK

DCKE

FLASH

ROM

PRD#, PWR#

PCE#

AD[0:7]

A[0:19]

EEP

ROM

SCL, SDA

RS232C(MTK)

RXD, TXD

2. SERVO Block Diagram

3-79

3. MPEG & MEMORY Block Diagram

IC503

SDRAM

16M

IC505

EEPROM

IIC501 (MPEG + DSP )

MT1379

IC5A1

FLASH MEMORY

(8 M )

IC510

(74HCT244)

Voltage level shift

VIDEO

Interface

AUDIO

Interface

RF IC

Interface

FRONT MICOM

Interface

(FRONT BOARD)

IC502

SDRAM

16M

RFOP,RFON,HTRC,RFRP,RFL

DCLK,WE,CAS,RAS

CS,DCKE,MA[0:10]

DQM0,DQM1

DQ[0:15]

DQM2,DQM3

DQ[16:31]

X501

27MHz

SCL,SDA

Y2(Y),Y3(Color)

Y4(Y),Y5(Cb),Y6(Cr)

ASPECT(16:9)

FEO,CSO,TEO,ADIN,BDO

SDATA,SDEN,SCLK,URST

FMSO,DMSO

V1P4,V2P8

TROPEN,TRSO,FOSO

ACLK,ALRCK,ABCK

MUTE,VSCK,VSDA

ASDTA[0:3]

ASTB,SCL,SDA

ASPDIF

PWR,PCE,PRD

A[0:19]

AD[0:7]

VFD_SCK

VFD_TXD

M_REQ

SCKO,TXDO,M-REQ

URST,S_REQ

VFD_RXD

3-80

4. VIDEO & AUDIO Block Diagram

IC5C1

VIDEO 6dB

Amp

IC401

AUDIO DAC

(2CH)

IC402

(OP Amp)

LPF&Buffer

CVBS

COMPONENT (R.G.B) / (Y.Pb.Pr )

SUPER VIDEO (Y/C)

(R.G.B) / (Y.Pb.Pr )

(Y/C)

DAC RESET

ACLK

SCL

SDA

INTERFACE

MPEG

AUDIO ‘R’

ADATA3

System not working or screen is abnormal

No Power on

No Video signal.

Video signal Y

Video signal Color

Digitron will not display System not working

Program download fail

3-81 3-82

CIRCUIT DIAGRAMS

1. SYSTEM CIRCUIT DIAGRAM

No CD/DVD LD

3-83 3-84

2. RF & DSP SERVO CIRCUIT DIAGRAM

3-85 3-86

3. AUDIO CIRCUIT DIAGRAM

3-87 3-88

4. AV/JACK CIRCUIT DIAGRAM

3-89 3-90

• CIRCUIT VOLTAGE CHART

PIN STOP PLAY STOP PLAY STOP PLAY STOP PLAY STOP PLAY STOP PLAY

1 1.03 2.99 0 0 1.22 1.22 3.27 3.28 0000 2 5.11 5.08 0 0 0 0 1.18 1.26 0 0 2.59 2.55 3 0 0 8.04 8.01 0.96 0.9 1.1 1.52 0000 4 0 0 0.12 0.06 2 2.06 0 0 0 0 2.59 2.56 5 5.11 5.07 0 0.06 0 1.51 0.66 1.07 3.28 3.29 0 0 6 0 1.95 3.64 3.69 1.48 1.47 0.85 1.12 3.28 3.29 3.24 3.23 7 0 0 3.62 3.61 0 1.56 3.27 3.28 0000 8 0 0 3.64 3.53 3.2 1.52 0.51 0.97 3.28 3.29 0.14 0.08

9 5.11 0 3.6 3.76 0.12 0.06 3.06 0 0 0 10 5.11 5.08 3.62 2.43 0.12 0.06 0 0 0 0 11 5.11 5.08 3.63 4.85 3.25 3.25 0.06 0.98 0.15 0.09 12 0 0 3.62 3.72 1.41 1.49 3.18 0.87 0 0 13 5.11 0 3.64 3.57 1.41 1.41 3.27 3.28 0.15 0.08 14 5.11 5.08 8.04 8.01 0 0 2.94 2.56 5.19 5.19 15 2.84 2.81 1.45 1.48 1.42 1.42 0.47 0.42 0.14 0.09 16 1.45 1.43 0.27 1.39 3.3 0 2.93 3.01 5.25 5.24 17 2.08 2.07 0.29 1.32 2.53 2.53 3.21 3.22 0.15 0.08 18 1.37 1.42 1.45 1.43 1.42 2.27 2.87 2.95 5.23 5.23 19 0.69 2.3 1.45 1.43 1.42 1.39 0.15 1.32 0 0 20 2.4 0 1.45 0.82 0 0 0 0.05 5.25 5.25 21 2.35 0 1.45 1.43 2.61 2.58 3.09 1.32 22 5.11 5.08 1.45 1.43 0.75 1.46 3.09 1.32 23 0 0 1.47 1.37 2.83 1 3.09 1.32 24 2.59 3.2 1.45 1.43 1.9 0.89 3.09 1.33 25 0.19 1.88 1.45 1.43 1.72 0.39 3.27 3.29 26 1.58 0 0.95 0.91 0.68 0.31 0 0 27 2.56 3.13 0 0 2.84 3.16 0.15 1.36 28 2 2.01 1.45 1.43 0 0 1.84 2.36 29 2 2.06 5.15 5.11 2.85 0.66 1 2.32 30 2.96 1.52 1.45 1.43 1.83 0.49 0.54 1.75 31 0 0 1.45 1.43 0.91 1.39 0.06 0.06 32 0.06 2.07 1.45 1.43 1.43 1.2 0.05 0.06 33 0.07 2.07 1.46 1.45 1.51 1.57 0 0 34 0 0 5.08 5.06 1.51 1.43 0.73 1.26 35 0 0 5.15 5.11 3.3 3.29 1.48 1.55 36 0 0 0 0 0.81 1.26 2.91 2.53 37 5.13 0 1.45 1.02 0.07 0 38 0 0 1.82 1.6 3.27 3.28 39 0 0 1.2 1.5 1.06 1.05 40 0 0 2 2.06 0.47 0.98 41 0 0 2.17 1.95 0 0 42 5.12 5.09 2.53 2.52 0 0.6 43 5.12 5.09 1.96 1.9 1.12 1.24 44 5.12 5.09 1.79 1.9 3.27 3.28 45 5.12 5.09 0.8 1.72 1.21 0.99 46 5.12 5.09 0.8 1.96 1.31 1.34 47 0 0 0.8 1.84 0 0 48 5.12 5.09 3.3 2.63 1.43 1.44 49 5.12 0 0 0.13 0.88 1.01 50 5.08 5.06 0 0.07 0 0 51 5.09 5.07 0 0 52 5.1 0 0 0 5300 00 54 5.13 0 0 0 55 0.09 0.2 3.25 3.27 56 1.61 0 1.21 1.18 5700 00 58 0 0 3.29 3.29 5900 00 6000 00 61 3.28 0 2.59 2.57 62 0 0 2.58 2.58 6300 00 64 0 0 2.59 2.56 65 0 0 3.29 3.29 66 0.26 0 3.3 3.29 67 5.12 5.08 3.29 3.29 68 0 0 2.57 2.56 69 5.12 0 5.19 5.18 70 3.21 2.03 2.59 2.57 71 3.46 2.2 0.12 0.08 72 2.81 0 2.53 2.52 73 0 0 2.59 2.57 74 0.21 0.09 3.29 3.29 75 0.22 0 2.61 2.61 76 0 0.1 3.27 3.24 77 0.21 0.09 0 0 78 0.23 0.09 0.94 1.04 79 0.21 0.08 0.78 1.06 80 0.23 0.08 0.89 1.15

STOP PLAY STOP PLAY STOP PLAY STOP PLAY

0.08 0.16 3.28 3.29 5.52 5.49 5.09 5.08

1.82 0.45 3.28 3.28 5.52 5.48 2.43 2.42

2.84 0 0 1.65 5.51 5.47 5.09 5.08

2.83 3.12 1.63 1.64 0 0 1.45 0

0.69 0.26 1.64 1.65 5.51 5.48 0 0

1.72 0.25 1.59 1.61 5.51 5.48 1.45 1.69

1.92 0.9 0 0 5.52 5.47 0 0

1.7 1.45 3.28 0 12.03 12.03 2.47 2.46 0 0 3.28 3.29 0 0 0 0 0 0 1.14 1.76

3.27 3.29 5.01 5.01 0 0

3.56 3.55 2.31 2.31 2.42 2.42

3.29 3.29 4.96 0 5.09 5.08 0 0 1.42 2.41 2.43 2.42

0.23 0.06 2.4 2.39 0 0 0 0 0 0 2.49 2.47 0 0 5.11 5.09 0 0 0 0.87 2.41 2.41 2.48 2.47

1.98 2.64 2.43 2.43 0 0

2.28 2.18 0 0 1.18 2.3

2.13 1.96 1.76 2.17

1.67 2.01 0 0

1.99 1.72 1.76 2.24

1.93 2.19 0 0

2.05 1.94 0 0 00 00 0 0 0.06 0.05 0 0 5.09 0

1.49 2.03

0.16 1.07

1.96 1.25

0.16 1.1

0.99 2.2

1.17 1.07

0.79 1.82

0.15 1.07

3.29 3.3

1.93 3.09

0.16 1.07

1.5 2.2

0.16 1.07

1.21 2.64

0.16 1.08

1.64 1.48

2.05 2.06 00 00

0.07 0.13

IC201

(MT1336E)

IC202

(MOTOR)

IC501

(MT1379)

IC502

(SDRAM)

IC505

(EEPROM)

IC510

(BUFFER)

IC5A1

(FLASH)

IC401

(CS4391)

IC402

(AMP)

IC5C1

(MM1623XFBE)

PIN STOP PLAY STOP PLAY STOP PLAY STOP PLAY STOP PLAY STOP PLAY

81 0.22 0 0.99 1.34 82 0 0 2.52 2.52 83 0 0 3.09 1.33 84 0.07 0 0.37 1.16 85 0.07 2.27 3.08 1.1 86 1.97 0 3.07 1.08 87 1.96 1.9 0.59 1.04 88 1.54 1.71 1.57 2.53 89 0.19 2.22 3.2 3.13 90 0.21 0 2.77 2.53 91 0.22 0.06 0.22 1.68 92 0.22 0 0 0 93 0.23 0.06 3.32 1 94 0.23 0.06 0.16 1.58 95 2.28 0 3.31 1.62 96 2.28 2.25 3.3 1.08 97 2.27 1.23 3.3 3.29 98 2.27 2.23 3.32 1.62

99 2.27 2.23 0.16 1.09 100 2.26 2.23 3.32 1.27 101 2.08 2.17 3.3 1.32 102 2.07 2.17 0 0 103 2.07 2.18 1.56 1.55 104 2.08 0 0.94 1.25 105 0.14 0.15 0.41 0 106 0.14 0.16 0.05 0.06 107 0 0 0 0.06 108 1.28 1.28 3.27 3.26 109 5.18 5.05 0 0 110 0.14 0.16 0.19 1.74 111 0.15 0.15 3.3 3.29 112 0.13 0.16 0.18 1.62 113 0.14 0.15 2.98 2.38 114 5.1 5.05 3.02 1.48 115 2.07 2.09 0 0 116 2.06 2.09 2.86 3.01 117 0 0 2.86 2.54 118 0 0 0 0 119 0 0 0 2.5 120 5.1 5.05 2.55 2.51 121 0.13 0.15 3.03 1.4 122 0.14 0.15 3.03 1.4 123 0 0.18 0.22 1.39 124 0 0.18 0.22 0.34 125 5.08 5.03 0 0 126 5.08 3.16 3.31 0.98 127 0.06 2.08 0.26 1.64 128 0 0 3.31 1.53 129 3.3 1.15 130 3.3 3.29 131 3.31 1.49 132 0.16 0.89 133 3.3 0 134 3.3 1.07 135 0 0 136 2.86 2.53 137 2.86 2.53 138 0.07 0.86 139 0.09 0.99 140 0.07 2.51 141 0.07 0.94 142 0.09 1.13 143 0.07 1.19 144 0.09 1.07 145 0.09 0 146 0 1.51 147 0.09 1.25 148 0.07 1.64 149 0.06 0 150 0 1.65 151 0.07 3.29 152 0 1.6 153 0 1.64 154 0 1.44 155 0 0 156 0 0 157 0 1.63 158 0 3.29 159 0 3.27 160 0 1.27

STOP PLAY STOP PLAY STOP PLAY STOP PLAY

IC201

(MT1336E)

IC202

(MOTOR)

IC501

(MT1379)

IC502

(SDRAM)

IC505

(EEPROM)

IC510

(BUFFER)

IC5A1

(FLASH)

IC401

(CS4391)

IC402

(AMP)

IC5C1

(MM1623XFBE)

3-91 3-92

PIN STOP PLAY STOP PLAY STOP PLAY STOP PLAY STOP PLAY STOP PLAY

161 0 1.27 162 0 2.35 163 0 0 164 0 0.73 165 0 3.27 166 0 0.5 167 0 0 168 0 0.53 169 0 3.27 170 0 0.59 171 0 0 172 3.01 0.72 173 0 0.72 174 0 0 175 0 2.73 176 0 3.13 177 0 3.13 178 0 3.25 179 0 0 180 0 0 181 2.04 2.64 182 0 2.52 183 0 0 184 0 0.09 185 0 3.26 186 - 187 0 0.08 188 0 0 189 0 0 190 0 0 191 0.23 0 192 0 3.29 193 0 0 194 0 0 195 0 0 196 0 0 197 0 1.63 198 0 0 199 0 0 200 0 2.15 201 0 1.44 202 0 1.44 203 0 1.43 204 0 1.43 205 0 1.42 206 0 2.1 207 0 2.07 208 0 1.41 209 0 1.52 210 0 1.43

211 0 2.81 212 0 3.28 213 0 0.12 214 0 0.12 215 1.02 1.43 216 0 1.43

STOP PLAY STOP PLAY STOP PLAY STOP PLAY

IC201

(MT1336E)

IC202

(MOTOR)

IC501

(MT1379)

IC502

(SDRAM)

IC505

(EEPROM)

IC510

(BUFFER)

IC5A1

(FLASH)

IC401

(CS4391)

IC402

(AMP)

IC5C1

(MM1623XFBE)

Q201 Q202 Q203 Q204

STOP PLAY STOP PLAY STOP PLAY STOP PLAY

E 0 0 0 0 0 0 5.14 4.34 C 0 5.09 0 0 0 0.19 0 2.42 B 0.68 0 0 5.04 5.04 0 5.08 3.64

Q205 Q501 Q6401

STOP PLAY STOP PLAY STOP PLAY

E 5.14 5.10 0 5.17 0 C 0.5 0 0 0 0 0.13 B 5.08 5.05 0.83 0.83 5.11 0

LOCATION GUIDE

3-93 3-94

PRINTED CIRCUIT DIAGRAMS

1. MTR P.C.BOARD

DECK MECHANISM PARTS LOCATIONS

• Top View . . . . . . . . . . . . . . . . . . . . . . . . .4-1

• Bottom View . . . . . . . . . . . . . . . . . . . . . . .4-1

DECK MECHANISM DISASSEMBLY

1. Drum Assembly . . . . . . . . . . . . . . . . . . .4-2

2. Top Plate Assembly . . . . . . . . . . . . . . . .4-4

3. CST Holder Assembly . . . . . . . . . . . . . .4-4

4. Door Opener . . . . . . . . . . . . . . . . . . . . .4-4

5. L/D Motor Bracket Assembly . . . . . . . . .4-4

6. F/L Gear Rack . . . . . . . . . . . . . . . . . . . .4-4

7. F/L Arm Assembly . . . . . . . . . . . . . . . . .4-4

8. S/W Lever Assembly . . . . . . . . . . . . . . .4-4

9. Cleaner Arm Assembly . . . . . . . . . . . . . .4-5

10. F/E Head . . . . . . . . . . . . . . . . . . . . . . . .4-5

11. A/C Head Base Assembly . . . . . . . . . . .4-5

12. T Brake Assembly . . . . . . . . . . . . . . . . .4-6

13. RS Brake Assembly . . . . . . . . . . . . . . . .4-6

14. Tension Arm Assembly . . . . . . . . . . . . . .4-6

15. S Reel / T Reel . . . . . . . . . . . . . . . . . . .4-6

16. P4 Base Assembly . . . . . . . . . . . . . . . . .4-7

17. Lid Opener . . . . . . . . . . . . . . . . . . . . . . .4-7

18. Pinch Arm Assembly . . . . . . . . . . . . . . .4-7

19. T/up / Arm T/up Lever . . . . . . . . . . . . . .4-7

20. Capstan Belt /Capstan Motor . . . . . . . . .4-8

21. F/R Lever . . . . . . . . . . . . . . . . . . . . . . . .4-8

22. D35 Clutch Assembly . . . . . . . . . . . . . . .4-8

23. Capstan Brake Assembly . . . . . . . . . . . .4-8

24. Drive Gear / Cam Gear . . . . . . . . . . . . .4-9

25. Sector Gear . . . . . . . . . . . . . . . . . . . . . .4-9

26. Slider Plate . . . . . . . . . . . . . . . . . . . . . .4-9

27. Tension Lever . . . . . . . . . . . . . . . . . . . .4-9

28. Spring Lever . . . . . . . . . . . . . . . . . . . . .4-9

29. P2 Gear Assembly/

P3 Gear Assembly . . . . . . . . . . . . . . . .4-10

30. P2 Base Assembly/

P3 Base Assembly . . . . . . . . . . . . . . . .4-10

31. Loading Base . . . . . . . . . . . . . . . . . . . .4-11

32. Tension Base . . . . . . . . . . . . . . . . . . . .4-11

33. Idler Arm Jog Assembly . . . . . . . . . . . .4-11

DECK MECHANISM ADJUSTMENT

• Tools and Fixtures for Service . . . . . . .4-12

1. Mechanism Alignment Position Check .4-13

2. Preparation for Adjustment . . . . . . . . . .4-14

3. Checking Torque . . . . . . . . . . . . . . . . .4-14

4. Guide Roller Height Adjustment . . . . . .4-15

4-1. Preliminary Adjustment . . . . . . . . .4-15

4-2. Precise Adjustment . . . . . . . . . . . .4-15

5. Audio/Control (A/C) Head Adjustment . .4-16

5-1. Preliminary Adjustment . . . . . . . . .4-16

5-2. Confirmation of Tape Path between

Pinch Roller and Take-up Guide . .4-17

5-3. Precise Adjustment

(Azimuth Adjustment) . . . . . . . . . .4-17

6. X-Value Adjustment . . . . . . . . . . . . . . .4-17

7. Adjustment after Replacing Drum Assembly

(Video Heads) . . . . . . . . . . . . . . . . . . .4-18

8. Check the Tape Travel after Reassembling

Deck Mechanism . . . . . . . . . . . . . . . . .4-18

8-1. Check Audio and RF Locking Time

during Playback after CUE or REV

. . . . . . . . . . . . . . . . . . . . . . . . . . .4-18

8-2. Check Tape Curling or Jamming . .4-18

MAINTENANCE/INSPECTION PROCEDURE

1. Check before starting Repairs . . . . . . .4-19

2. Required Maintenance . . . . . . . . . . . . .4-20

3. Scheduled Maintenance . . . . . . . . . . . .4-20

4. Supplies Required for Inspection and

Maintenance . . . . . . . . . . . . . . . . . . . .4-20

5. Maintenance Procedure . . . . . . . . . . . .4-20

5-1. Cleaning . . . . . . . . . . . . . . . . . . . .4-20

5-2. Greasing . . . . . . . . . . . . . . . . . . . .4-21

MECHANISM TROUBLESHOOTING GUIDE

1. Deck Mechanism . . . . . . . . . . . . . . . . .4-23

2. Front Loading Mechanism . . . . . . . . . .4-26

EXPLODED VIEWS

1. Front Loading Mechanism Section . . . .4-28

2. Moving Mechanism Section (1) . . . . . . .4-29

3. Moving Mechanism Section (2) . . . . . . .4-30

CONTENTS

SECTION 4 MECHANISM OF VCR PART

DECK MECHANISM PARTS LOCATIONS

4-1

• Top View

• Bottom View

20

24

23

20

24

22

21

29

30

29

30

25 32 27 26 28

NOTE: When reassembly perform the

procedure in the reverse order.

1 Drum Assembly 3 Screw A-1 T

2 Top Plate Assembly 2 Hook A-2 T

2 3 CST Holder Assembly Chassis Hole A-2 T

2 4 Door Opener Chassis Hole A-2 T

5 L/D Motor Bracket 3 Hook A-2 T

Assembly

2,3,4 6 F/L Gear Rack 1 Hook, Chassis Hole A-2 T

2,3,4,6 7 F/L Arm Assembly Chassis Hole A-2 T

8 S/W Lever Assembly 1 Hook A-2 T

9 Cleaner Arm Assembly Chassis Embossing A-3 T

10 F/E Head Chassis Embossing A-3 T

11 A/C Head Base Assembly 1 Screw A-3 T

2,3 12 T Brake Assembly 1 Hook A-4 T

2,3 13 RS Brake Assembly 1 Hook A-4 T

2,3 14 Tension Arm Assembly 2 Hook A-4 T

2,3,12,13, 15 S Reel / T Reel A-4 T

14

16 P4 Base Assembly Chassis Embossing A-5 T

17 Lid Opener Chassis Embossing A-5 T

17 18 Pinch Arm Assembly Shaft A-5 T

17 19 T/up / Arm T/up Lever 1 Hook A-5 T

17,18 20

Capstan Belt /Capstan Motor

3 Screw A-6 B

21 F/R Lever Locking Tab A-6 B

20, 21 22 D35 Clutch Assembly Washer A-6 B

23 Capstan Brake Assembly Locking Tab A-6 B

24 Drive Gear / Cam Gear Washer/Hook A-7 B

25 Sector Gear 1 Hook A-7 B

20,21,23, 26 Slider Plate Shaft Guide A-7 B

24,25

20,21,23, 27 Tension Lever 1 Hook A-7 B

24,25,26

2,3,14,20, 28 Spring Lever Locking Tab A7 B

21,25,23,

24,26

25 29

P2 Gear Assembly/P3 Gear Assembly

Boss A-8 B

2,3,14,25, 30

P2 Base Assembly/P3 Base Assembly

Chassis Slot A-8 B

29

2,3,14,25, 31 Loading Base 1 Screw A-9 T

29

2,3,14 32 Tension Base Chassis Embossing A-9 B

2,3,20,21, 33 Idler Arm Jog Assembly Locking Tab A-9 T

22

Starting No.

Procedure

Part Fixing Type

Fig-

ure

1) When reassembling, confirm Mechanism and Mode Switch Alignment Position (Refer to Page 4-14)

2) When disassembling, the Parts in the "Starting No." colum should be removed first.

R: Top, B:Bottom

2

7

10

1

31

14

15

8

6

3

4

9

5

11

18

16

17 19 19

12

33

13

15

4-2

DECK MECHANISM DISASSEMBLY

(S3)

(S2)

(S3)

(A)

Stator

Carbon Brush

Drum Motor

Rotor

Drum Sub Assembly

FPC Drum

(S1)

FPC Holder

H1

H2

1. Drum Assembly (Fig. A-1-1)

1) Unplug the FPC Drum Connector.

2) Remove three Screws (S1) on the bottom side and separate the Drum assembly.

3) Unhook (H1), (H2) and separate the FPC Holder and FPC Cap. (See Fig. B-1)

1-1. Drum Motor

1) Remove two Screws (S2) and disassemble the Stator of the Drum Motor.

(2) Remove two Screws (S3) and separate the Rotor of the

Drum Motor from the Drum Sub assembly.

When reassembling, check to ascertain that the Carbon Brush is in position.

Fig. A-1

NOTE

(Fig. B-1)

FPC Holder

FPC Drum

FPC Cap

Figure in the opposite direction

(Fig. A-1-1)

DECK MECHANISM DISASSEMBLY

4-3

(B)

(E)

(C1)

(C)

Top Plate

F/L Arm Assembly

S/W Spring Lever

F/L Gear Rack Assembly

Chassis

Door Opener

L/D Motor Bracket Assembly

CST Holder Assembly

(B')

(C')

(D)

(E')

(H6)

(A)

(B)

S/W Lever Assembly

(H8)

Fig. A-2

(Fig. A-2-1)

(Fig. A-2-2)

(Fig. A-2-6)

(Fig. A-2-7)

(Fig. A-2-5)

(Fig. A-2-3)

(Fig. A-2-4)

4-4

DECK MECHANISM DISASSEMBLY

2. Top Plate Assembly (Fig. A-2-1)

1) Pull the (B) portion of the Top Plate back in direction of arrow and separate the right side of it.

2) Pull the (B’) portion of the Top Plate back in direction of arrow and separate the left side of it. (Tools: (-) Flat type screwdriver or any tool with a sharp or flat point.)

(1) When reassembling, push the Top Plate on after aligning

the two position (C), (C’) as Fig.

3. CST Holder Assembly (Fig.A-2-2)

1) Move the CST Holder Assembly in direction of arrow and separate the left side of it first through the (D) position of the Chassis.

2) Disassemble the right side of the CST Holder Assembly from each guided hole of the Chassis.

When reassembling, insert the (E) part of the CST Holder assembly in the (E’) hole of the Chassis first and assemble the left side of it.

4. Door Opener (Fig.A-2-3)

5. L/D Motor Bracket Assembly (Fig. A-2-4)

1) Unplug the Connector (C1).

2) Unhook three Hooks (H3, H4, H5) on thr bottom side of the Chassis, lift up the L/M Bracket Assembly and disasemble the L/D Motor Bracket Assembly.

6. F/L Gear Rack (Fig. A-2-5)

1) Move the F/L Gear Assembly Rack in the direction of

arrow (A) and unhook the Hook (H6) pulling back in front.

2) Separate the F/L Rear Rack in direction of arrow (B).

When reassembling, align the Gear part of the Gear F/L Assembly Rack with the Drive Gear as below Fig.

7. F/L Arm Assembly (Fig. A-2-6)

1) Move the F/L Arm Assembly in direction of arrow and

separate the left side of it first.

2) Disassemble the F/L Arm Assembly from each guided

Holes in of the Chassis.

8. S/W Lever Assembly (Fig. A-2-7)

1) Hook the S/W Spring Lever on the Hook (H7) first as

shown below.

2) Unhook the Hook (H8) in the left side of the Chassis and

move the S/W Lever Assembly.

(B')

(C')

(C)

(B)

NOTE

(H3)

(H4)

(H5)

Bracket assembly L/M

NOTE

F/L Gear Rack

Holder assembly CST

(D)

Chassis

Drive Gear

Chassis

(H8)

(H7)

S/W Spring Lever

DECK MECHANISM DISASSEMBLY

4-5

9. Cleaner Arm Assembly (Fig. A-3-1)

1) Carefully pry tab "A" (see Fig.A-3-1) to clear the embossed tab on the chassis. Turn the Cleaner Arm Assembly clockwise and lift it from the chassis.

10. F/E Head (Fig. A-3-2)

1) Carefully pry tab "A" (see Fig.A-3-2) to clear the embossed tab on the chassis. Turn the Cleaner Arm Assembly counter-clockwise and lift it from the chassis.

11. A/C Head Base Assembly (Fig. A-3-3)

1) Remove the Screw (S4) and lift the A/C Head Base Assembly up.

(A)

Cleaner

Arm Assembly

A/C Head Base Assembly

(S4)

F/E Head

(A)

Chassis

Fig. A-3

(Fig. A-3-1)

(Fig. A-3-3)

(Fig. A-3-2)

4-6

DECK MECHANISM DISASSEMBLY

T Brake Assembly

TB Spring

(H9)

T Reel

RS Brake Assembly

RS Spring

Tension Arm Assembly

Tension Spring

S Reel

Tension Base

(H11)

(H12)

Chassis

(H10)

Fig. A-4

12. T Brake Assembly (Fig. A-4-1)

1) Unhook the TB Spring from the Hook (H9) of the Chassis.

2) LLift the T Brake Assembly up.

13. RS Brake Assembly (Fig. A-4-2)

1) Unhook the RS Spring from the Hook (H10) of the Chassis.

2) Lift the T Brake Assembly up.

14. Tension Arm Assembly (Fig. A-4-3)

1) Unhook the Tension Spring from the Hook (H11) of the Tension Arm Assembly.

2) Unhook the Hook (H12) of the Tension Base and lift the Tension Arm Assembly up.

Difference for Springs

15. S Reel / T Reel (Fig. A-4-4)

1) Difference for S Reel / T Reel

TB Spring RS Spring Tension Spring

(Difference for Springs)

Color (Black)

S Reel T Reel

NOTE

(Fig. A-4-1)

(Fig. A-4-3)

(Fig. A-4-4)

(Fig. A-4-2)

DECK MECHANISM DISASSEMBLY

4-7

Lid Opener

Pinch Arm

Assembly

P4 Base Assembly

T/up Arm

T/up Lever

(A)

(B)

(C)

(H13)

(B)

(H13)

Chassis

Fig. A-5

16. P4 Base Assembly (Fig. A-5-1)

1) Carefully pry the (A) portion of the P4 Base Assembly from the Embossing of the Chassis.

2) Turn the P4 Base Assembly counterclockwise and lift it up.

17. Lid Opener (Fig. A-5-2)

1) Carefully pry the (B) portion of the Lid Opener from the Embossing of the Chassis.

2) Turn the Lid Opener to clockwise direction and lift it up.

18. Pinch Arm Assembly (Fig. A-5-3)

1) Lift the Pinch Arm Assembly up.

19. T/up (Fig. A-5-4)/ Arm T/up Lever (Fig. A-5-5)

1) Unhook the Hook (H13) of the bottom Chassis and lift the

T/up Lever up.

2) Lift the T/up Arm up.

When reassembling, confirm the (C) portion of the Pinch Arm Assembly is inserted in the Chassis Hole correctly.

Place the Mechanism face down, or up side down.

NOTE

(Fig. A-5-2)

(Fig. A-5-1)

(Fig. A-5-3)

(Fig. A-5-5)

(Fig. A-5-4)

4-8

DECK MECHANISM DISASSEMBLY

Chassis

(S5)

Capstan Belt

Capstan Motor

Washer(W1)

F/R Lever

D35 Clutch Assembly

Capstan Brake Assembly

(L1)

(L2)

(L1)

Fig. A-6

20. Capstan Belt (Fig. A-6-1)/ Capstan Motor (Fig. A-6-2)

1) Remove the Capstan Belt..

2) Remove the three Screws (S5) from the bottom of the

Chassis and lift the Capstan Motor up.

21. F/R Lever (Fig. A-6-3)

1) Unlock the Locking Tab (L1) as Fig. A-6-3 and lift the F/R

Lever up.

22. D35 Clutch assembly (Fig. A-6-4)

1) Remove the Washer (W1) and lift the D35 Clutch Assembly up.

23. Capstan Brake Assembly

(Fig. A-6-5)

1) Pull the Locking Tab (L2) back in the direction of the arrow and lift it up.

(Fig. A-6-1)

(Fig. A-6-2)

(Fig. A-6-3)

(Fig. A-6-5)

(Fig. A-6-4)

DECK MECHANISM DISASSEMBLY

4-9

Drive Gear

Washer (W2)

Cam Gear

Slider Plate

Tension Lever

Spring Lever

Loading Base

Sector Gear

(L3)

(H15)

(H16)

(H14)

(A)

Chassis

Drive Gear Hole(C)

Cam Gear Hole(B)

Drive Gear Hole(A)

Fig. A-7

24. Drive Gear (Fig. A-7-1)/ Cam Gear (Fig. A-7-2)

1) Remove the Washer (W2) and lift the Drive Gear up.

2) Unhook the Hook (H14) of the Cam Gear and lift the Cam

Gear up.

When reassembling, align the Drive Gear Hole (A) and the Cam Gear Hole (B) in a straight line after the Drive Gear Hole (C) is aligned with the Chassis Hole.

25. Sector Gear (Fig. A-7-3)

1) Unhook the Hook (H15) of the Loading Base on bottom

Chassis and lift the Sector Gear up.

26. Slider Plate (Fig. A-7-4)

1) Lift the Slider Plate up.

27. Tension Lever (Fig. A-7-5)

1) Unhook the (A) portion of the Tension Lever from the Hook (H16) of the Chassis.

2) Turn the Tension Lever counterclockwise and lift it up.

28. Spring Lever (Fig. A-7-6)

1) Unlock the Locking Tab (L3) from the bottom of the Chassis and lift the Spring Lever up.

(Fig. A-7-4)

(Fig. A-7-5)

(Fig. A-7-6)

(Fig. A-7-1)

(Fig. A-7-2)

(Fig. A-7-3)

NOTE

4-10

DECK MECHANISM DISASSEMBLY

P3 Gear Assembly

P2 Gear Assembly

P2 Base Assembly

P3 Base Assembly

(A)

(B)

Chassis

P2 Gear Assembly Hole

Sector Gear Hole(A)

Slider Plate Hole(B)

Spring Lever Boss

P3 Gear Assembly Hole

Fig. A-8

29. P2 Gear Assembly (Fig. A-8-1)/ P3 Gear Assembly (Fig. A-8-2)/

1) Lift the P2 Gear Assembly up.

2) Lift the P3 Gear Assembly up.

When reassembling, align the two Holes of the P2 and P3 Gear Assembly in a straight line after confirming the Sector Gear Hole (A) and the Slider Plate Hole (B) are aligned as in the above Fig.

30. P2 Base Assembly (Fig. A-8-3)/ P3 Base Assembly (Fig. A-8-4)

1) Move the P2 Base Assembly in the direction of the arrow

(A) along the slot of the Chassis and disassemble it from the bottom side.

2) Move the P3 Base Assembly in the direction of the arrow

(B) along the slot of the Chassis and disassemble it from the bottom side.

Place the Mechanism face up, or return to it's original position.

NOTE

(Fig. A-8-1)

(Fig. A-8-2)

(Fig. A-8-3)

(Fig. A-8-4)

DECK MECHANISM DISASSEMBLY

4-11

(A)

(B) (C)

(S7)

Idler Arm Jog Assembly

Loading Base

Tension Base

Chassis

(D)

Fig. A-9

31. Loading Base (Fig. A-9-1)

1) Remove the Screw (S7).

2) Lift the Loading Base up.

32. Tension Base (Fig. A-9-2)

1) Remove the (A) portion of the Tension Base from the Embossing of the Chassis.

2) Turn the Tension Base counterclockwise and lift it up.

33. Idler Arm Jog Assembly (Fig. A-9-3)

1) Pinch (B) and (C), as shown in Fig. A-9-3.

2) Lift the Idler Arm Assembly up.

When disassembling, be careful not to catxh part (D) on the Chassis (see inset).

NOTE

(Fig. A-9-1)

(Fig. A-9-2)

(Fig. A-9-3)

DECK MECHANISM DISASSEMBLY

4-12

• Tools and Fixfures for Service

1. Cassette Torque meter SRK-VHT-303 (Not SVC part) Part No: D00-D006

4. Torque gauge adaptor Part No:D09-R001

5. Post height adjusting driver Part No:DTL-0005

6. + Type driver (ø 5)

2. Alignment tape Part No NTSC: DTN-001 PAL:DTN-0002

3. Torque gauge

3. 600g.Cm ATG

3. Part No:D00-D002

SRK

V

ID

E

O

C

A

S

E

T

E

T

O

R

Q

U

E

M

E

T

E

R

V

H

T-30

3

S

R

K

-

V

H

T

-

S

R

K

-

V

H

T

300

250

200 1

50

5

0

300

250

2

00

15

0

50

0

1

00

DECK MECHANISM ADJUSTMENT

4-13

Purpose:To determine if the Mechanism is in the correct position, when a Tape is ejected.

1. Mechanism Alignment position Check

1) Turn the Power S/W on and eject the Cassette by pressing the Eject Button.

2) Remove the Top Cover and Top Plate Assembly, visually check if the Cam Gear Hole is aligned with the Chassis Hole as below Fig. C-2.

3) If not, rotate the Shaft of the Loading Motor Clockwise or Counterclockwise until the Alignment is as shown below in Fig. C-2.

4) Remove the Screw which attaches the Deck Mechanism and Main Frame, confirm the Cam Gear is aligned with the Drive Gear as shown below in Fig. C-1 (A).

5) Confirm if the Mode S/W on the Main P.C. Board is aligned as shown below in Fig. C-1 (B).

6) Remount the Deck Mechanism on the Main P.C. Board and check each operation.

Cam Gear

Drive Gear

(C)

Mode S/W

(B)

Test Equipment/ Fixture

• Blank tape

Test Conditions (Mechanism

Condition)

• Eject Mode (with Cassette ejected)

Check Point

• Mechanism and Mode Switch Position

Fig. C-1

Fig. C-2

CHECK DIAGRAM

BOTTOM VIEW

TOP VIEW

Gear Cam (o) and Gear Drive (o) groove alignment

L/D Motor Assembly

(A')

(B')

Cam Gear

Chassis Hole

(B)

(A)

Cam Gear Hole Cam Gear Hole

4-14

DECK MECHANISM ADJUSTMENT

Purpose: To insure smooth Transport of the Tape during each Mode of Operation.

If the Tape Transport is abnormal, then check the Torque as indicated by the chart below.

2. Preparation for Adjustment (To set the Deck Mechanism to the Loading state without inserting a Cassette Tape).

1) Unplug the Power Cord from the AC Outlet.

2) Disassemble the Top Cover and Top Plate Assembly.

3) Plug the Power Cord into the AC Outlet.

4) Turn the Power S/W. Push the Stop Lever of the CST Holder Assembly to the back for Loading without the

Tape. Cover the Holes of the End Sensors at the both sides of the (L) Side Bracket and Door Bracket Assembly to prevent sensing light. Then The Deck Mechanism drives to the Stop Mode. In this case, The Deck Mechanism can accept inputs of each mode, however the Rewind and Review Operation can not be performed for more than a few seconds because the Take-up Reel Table is in the Stop Mode and can not detect the Reel Pulses.

3. Checking Torque

The Values are measured by using a Torque Gauge and Torque Gauge Adaptor with the Torque Gauge affixed.

The Torque reading to measure occurs when the Tape abruptly changes direction from Fast Forward of Rewind Mode, when quick bracking is applied to both Reels.

SRK

VIDEO

CASSETTE

TORQUE

METER

VHT-303

S

R

K

-

V

H

T

-

S

R

K

-

V

H

T

300

250

200

150

50

0

300

250

200

150

50

0

100

Test Equipment/ Fixture

• Torque Gauge (600g/cm ATG)

• Torque Gauge Adaptor

• Cassette Torque Meter

SRK-VHT-303

Checking Method

• Perform each Deck Mechanism Mode without inserting a Cassette Tape (Refer to above No.2 Preparation for Adjustment).

• Read the Measurement of the Take-up or Supply Reels on the Cassette Torque Meter (Fig. C-3-2).

• Attach the Torque Gauge Adaptor to the Torque Gauge and then read the Value of it (Fig. C-3-1).

NOTE:

Fig. C-3-2 Fig. C-3-1

Torque Gauge

Torque Gauge Adaptor

Reel Table

Item

Fast Forward Torque

Rewind Torque

Play Take-Up Torque

Review Torque

Mode

Fast Forward

Rewind

Play

Review

Test Equipment

Cassette Torque Gauge

Cassette Torque Meter

Measurement Reel

Take-Up Reel

Supply Reel

Take-Up Reel

Supply Reel

Measurement Values

More than 400g/cm

40~100g/cm

120~210g/cm

Test Conditions

(Mechanism Condition)

• Play (FF) or Review (REW) Mode

NOTE:

• Cassette Torque Meter (SRK-VHT-303)

• Torque Gauge (600g.cm ATG)

DECK MECHANISM ADJUSTMENT

4-15

4.Guide Roller Height Adjustment

Adjustment Procedure

1) Confirm that the Tape runs along the Tape Guide Line of the Lower Drum.

2) If the Tape runs at the Bottom of the Guide Line, turn the Guide Roller Height Adjustment Screw Clockwise.

3) If it runs at the Top, turn Counterclockwise.

4) Adjust the Height of the Guide Roller to be guided to the Guide Line of the Lower Drum from the Starting and Ending Point of the Drum.

Purpose: To regulate the Height of the Tape so that the Bottom of the Tape runs along the

Tape Guide Line on the Lower Drum.

Test Equipment/ Fixture

• Post Height Adjusting Driver

Test Conditions (Mechanism Condition)

• Play or Review Mode

Adjustment Point

• Guide Roller Height Adjustment screws on the Supply and Take-Up Guide Rollers.

Fig. C-4-1

Upper Flange

Guide Roller Retaining Screw

Guide Roller Height Adjustment screw

ADJUSTMENT DIAGRAM

Test Equipment/Fixture

• Oscilloscope

• Alignment Tape

• Post Height Adjusting

Driver

Test Equipment Connection Points

• CH-1:PB RF Envelope

• CH-2:NTSC: SW 30Hz

PAL: SW 25Hz

• Head Switching Output Point

• RF Envelope Output Point

Test Conditions VCR (VCP) State

• Play an Alignment Tape

Adjustment Point

• Guide Roller Height Adjustment Screws

Fig. C-4-2

Fig. C-4-3

P3 POST ADJUSTMENT

P2 POST ADJUSTMENT

Turn the Roller Guide Height Adjustment Screw slightly to flatten the waveform.

Tracking control at center

RF ENVELOPE OUTPUT TEST POINT

OSCILLOSCOPE

HEAD SWITCHING OUTPUT TEST POINT

Turn (Move) the tracking control to both directions

4-1. Preliminary Adjustment

4-2. Precise Adjustment

Adjustment Procedure

1) Play an Alignment Tape after connecting the Probe of the Oscilloscope to the RF Envelope Output Test Point and Head Switching Output Test Point.

2) Tracking Control (in PB Mode): Center Position (When this Adjustment is performed after the Drum Assembly has been replaced, set the Tracking Control so that the RF Output is Maximum).

3) Height Adjustment Screw: Flatten the RF Waveform. (Fig. C-4-2)

4) Turn (Move) the Tracking Control (in PB Mode) Clockwise and Counterclockwise. (Fig. C-4-3)

5) Check that any Drop of RF Output is uniform at the Start and End of the Waveform.

If the adjustment is excessive or insufficient the tape will jam or fold.

NOTE

Waveform Diagrams

Connection Diagram

4-16

DECK MECHANISM ADJUSTMENT

5. Audio/Control (A/C) Head Adjustment

10.9

Purpose: To insure that the Tape's Audio and Control Tracks pass accurately over the

head in exact alignment in both the Record and Playback Modes.

Test Equipment/ Fixture

• Blank Tape

• Screw Driver (+) Type 5mm

• Play the blank tape

Test Conditions (Mechanism Condition)

Adjustment Point

• Tilt Adjustment Screw (C)

• Height Adjustment Screw (B)

• Azimuth Adjustment Screw (A)

Fig. C-5-1

A/C Head Base

Fig. C-5-2

Height Adjustment

Screw (B)

Tilt Adjustment

Screw (C)

Azimuth Adjustment Screw (A)

X-Value Adjustment Hole

Fixed Screw

Fig. C-5-3

A/C Head

Tap e

Tape

0.2~0.25mm

P4

5-1. Preliminary Adjustment (Height and Tilt Adjustment)

Perform the Preliminary Adjustment, when there is no Audio Output Signal with the Alignment Tape.

1) Adjust the A/C Head Base Assembly as shown Fig. C-51 by using the Height Adjustment Screw (B).

2) Play a Blank Tape and observe if the Tape passes accurately over the A/C Head without the Tape Curling or Folding.

3) If Folding or Curling occurs adjust the Tilt Adjustment Screw (C) while the Tape is running to resemble Fig. C5-3.

4) Reconfirm the Tape Path after playback of approximately 4~5 seconds.

Ideal A/C head height occurs when the tape runs between

0.2~0.25mm above the bottom edge of the A/C head core.

NOTE

Adjustment Procedure/Diagrams

A/C Head Assembly

DECK MECHANISM ADJUSTMENT

4-17

Purpose: To obtain compatibility with other VCR (VCP) Models.

5-2. Confirm that the Tape passes smoothly

between the Take-up Guide and Pinch Roller (using a Mirror or the naked eye).

1) After completing Step 5-1. (Preliminary Adjustment), check that the Tape passes around the Take-up Guide and Pinch Roller without Folding or Curling at the Top or Bottom. (1) If Folding or Curling is observed at the Bottom of

the Take-up Guide then slowly turn the Tilt Adjustment Screw (C) in the Clockwise direction.

(2) If Folding or Curling is observed at the Top of it then slowly turn the Tilt Adjustment Screw (C) in the Counterclockwise direction.

Check the RF Envelope after adjusting the A/C Head, if the RF Waveform differs from Fig. C-5-4, performs Precise Adjustment to flat the RF Waveform.

Test Equipment/ Fixture

• Oscilloscope

• Alignment Tape (SP)

• Screw Driver (+) Type 5mm

Connection Point

• Audio output jack

Test Conditions

(Mechanism Condition)

• Play an Alignment Tape 1KHz, 7KHz Sections

Adjustment Point

• Azimuth Adjustment Screw (A)

• Height Adjustment Screw (B)

1) Connect the Probe of the Oscilloscope to the Audio Output Jack.

2) Alternately adjust the Azimuth Adjustment Screw (A) and the Tilt Adjustment Screw (C) for Maximum Output of the 1Khz and 7Khz segments, while maintaining the flattest Envelope differential between the two Frequencies.

Adjustment Procedure

5-3. Precise Adjustment (Azimuth adjustment)

6. X-Value Adjustment

Fig. C-5-4

1KHZ

• Oscilloscope

• Alignment tape (SP only)

• Screw Driver (+) Type 5mm

• CH-1: PB RF Envelope

• CH-2: NTSC: SW 30Hz

PAL: SW 25Hz

• Head Switching Output Test Point

• RF Envelope Output Test Point

Test Conditions

(Mechanism Condition)

• Play an Alignment Tape

Adjustment PointConnection PointTest Equipment/ Fixture

Adjustment Procedure

1) Release the Automatic Tracking to run long enough for Tracking to complete it’s Cycle.

2) Loosen the Fixed Mounting Screw and move the A/C Head Base Assembly in the direction as shown in the Diagram to find the center of the peak that allows for the maximum Waveform Envelope. This method should allow the 31um Head to be centrally located over the 58um Tape Track.

3) Tighten the A/C Head Base Assembly mounting Screw.

7KHZ

A:Maximum

B:Maximum

Left

Right

Groove at the Base A/C

Height Adjustment Screw (B)

Tilt Adjustment Screw (C)

Azimuth Adjustment Screw (A)

X-Value Adjustment Hole

Fixed Screw

RF ENVELOPE OUTPUT TEST POINT

OSCILLOSCOPE

HEAD SWITCHING OUTPUT TEST POINT

Connection Diagram

Adjustment Diagram

NOTE:

CH-1

CH-2

4-18

DECK MECHANISM ADJUSTMENT

Purpose: To correct for shift in the Roller Guide and X value after replacing the Drum.

8-2. Check for tape curling or jamming

Test Equipment/ Fixture

• T-160 Tape

• T-120 Tape

Specification

• Be sure there is no tape jamming or curling at the begining, middle or end of the tape.

VCR(VCP) State

•

Run the CUE, REV play mode at the beginning and the end of the tape.

Test Conditions (Mechanism Condition)

1) Confirm that the tape runs smoothly around the roller guides, drum and A/C head assemblies while abruptly changing operating modes from Play to CUE or REV. This is to be checked at the begining, middle and end sections of the cassette.

2) Confirm that the tape passes over the A/C head assembly as indicated by proper audio reproduction and proper tape counter performance.

Checking Procedure

7. Adjustment after Replacing Drum Assembly (Video Heads)

Test Equipment/ Fixture

• Oscilloscope

• Alignment tapes

• Blank Tape

• Post Height Adjusting Driver

• Screw Driver (+) Type 5mm

Connection Point

• CH-1: PB RF Envelope

• CH-2: NTSC: SW 30Hz

PAL: SW 25Hz

• Head Switching Output Test Point

• RF Envelope Output Test Point

Test Conditions

(Mechanism Condition)

• Play the blank tape

• Play an alignment tape

Adjustment Points

• Guide Roller Precise Adjustment

• Switching Point

• Tracking Preset

• X-Value

Checking/Adjustment Procedure

Play a blank tape and check for tape curling or creasing around the roller guide. If there is a problem, follow the procedure 4. "Guide Roller Height" and 5. "Audio Control (A/C) Head Adjustment".

RF ENVELOPE OUTPUT TEST POINT

OSCILLOSCOPE

HEAD SWITCHING OUTPUT TEST POINT

Connection Diagram

Waveform

V1/V MAX EE0.7

V2/V MAX EE0.8 RF ENVELOPE OUTPUT

Fig. C-7

8. Check the Tape Travel after Reassembling Deck Assembly.

8-1. Check Audio and RF Locking Time during playback and after CUE or REV (FF/REW)

Test Equipment/ Fixture

• Oscilloscope

• Alignment tapes (with 6H

3kHz Color Bar Signal)

• Stop Watch

Specification

• RF Locking Time: Less than 5 sec.

• Audio Locking Time:Less than 10sec

Test Equipment

Connection Points

• CH-1: PB RF Envelope

• CH-2: Audio Output

• RF Envelope Output Point

• Audio Output Jack

Test Conditions

(Mechanism Condition)

• Play an alignment tape (with 6H 3kHz Color Bar Signal)

Checking Procedure

Play an alignment tape then change the operating mode to CUE or REV and confirm if the unit meets the above listed specifications.

1) CUE is fast forward mode (FF)

2) REV is the rewind mode (REW)

3) Referenced to the Play mode

NOTES:

V1

V

V2

CH1 CH2

Connection Points

MAINTENANCE/INSPECTION PROCEDURE

4-19

(3) F/E Head

(5) Drum Assembly

(Video Head)

(4) P2 Base

Assembly

(2) Tension Post

(1) Supply Reel

(6) P3 Base Assembly

The following faults can be remedied by cleaning and oiling. Check the needed lubrication and the conditions of cleanliness in the unit. Check with the customer to find out how often the unit is used, and then determine that the unit is ready for inspection and maintenance. Check the following parts.

1 Check before starting repairs

Phenomenon Inspection

Replace-

ment

Color beats Dirt on full-erase head

o

Poor S/N, no color

Dirt on video head

Vertical or Horizontal jitter

Dirt on Audio/control head

Dirt on pinch roller

If locations marked with o do not operate normally after cleaning, check for wear and replace. See the EXPLODED VIEWS at the end of this manual as well as the above illustrations See the Greasing (Page 4-22) for the sections to be lubricated and greased.

NOTE

o

Dirt on video head

Dirt on tape transport system

Low volume,

Sound distorted

Tape does not run.

Tape is slack

o

In Review and Unloading (off mode), the Tape is rolled up loosely.

Clutch Assembly D33K Torque reduced

Cleaning Drum and transport system

Fig. C-9-3

(7) A/C Head

(8) P4 Post

(10) Pinch Roller

(11) Take-up Guide Post

(9) Capstan Shaft

(12) Take-up Reel

* No. (1) ~ (13) Indicates the Tape Path to be traveled from Supply Reel to Take-up Reel.

Fig. C-9-1 Top View

Fig. C-9-2 Bottom View

F/E Head

Video Head

A/C Head

Pinch Roller

Belt Capston

Clutch

Assembly D33K

Fig. C-9-3 Tape Transport System

Zenith XBV323 Schematic

Specifications and Main Features

Frequently Asked Questions

User Manual