SHARP VT-3418X, VT-5118X Service Manual

SHARP CORPORATION

N.S.W. SEWVIGE

1

HUNTINGWOOD DE;/.

BLACKTOVVEil

N.S.W.

DEPT.

2148

W-341 8X VT-5118X

SERVICE MANUAL

S94D8VT3418Xi

TV/VCR COMBINATION

i==T=D

TELEVIDEO

Chassis No. VP-

7

VT-341 8X

In the interests of user-safety (Required by safety regulations in some countries ) the set should be restored to its original condition and only parts identical to those specified should be used.

FEATURE

n Full Auto Search Tuning System n

On Screen Digital Channel/Sound Level/ Tuning Display, Control (Contrast, Brightness, Tint, P-Tone) Symbol and Level

H

Blue Back Off Timer

n

40 Key, Wireless Remote Control Unit

n Channel Skip

H

Dew Warning Indicator

W DPSS

(Digital Program Search System)

VT-51

18X

Colour,

MODELS

H

High Speed Video Search System

l

PAUSECAM: 7 times

l

NTSC:

w

Quick Start Playback with Full Loading System

n

Still/Slow Function with Noiseless Frame Still

n

Digital Automatic Tracking Control

n

Automatic Playback Function

n

AHC

(Automatic Head Cleaning System)

VT-51

5

times(SP),

15 times

18X

(EP)

I

.

SPECIFICATIONS

l

IMPORTANT SERVICE NOTES

l

LOCATION OF USER’S CONTROL

.

DISASSEMBLY AND REASSEMBLY

. ADJUSTMENT OF THE

TV ELECTRICAL CIRCUITRY

.

FUNCTION OF MAJOR MECHANICAL PARTS

. ADJUSTMENT, REPLACEMENTAND

ASSEMBLY OF MECHANICAL UNITS

. ADJUSTMENT OF THE

VCR ELECTRICAL CIRCUITRY

. TROUBLESHOOTING

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

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

.........

........

...........

.........

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

CONTENTS

Page Page

l

2 3

4 7

8

14

..

16

41 47

OVERALL SCHEMATIC DIAGRAM

l

CHASSIS LAYOUT OF TV SECTION

l

BLOCK DIAGRAM OF TV SECTION

.

DESCRIPTION OF TV SECTION

SCHEMATIC DIAGRAM

.

CHASSIS LAYOUT OF VCR SECTION

.

BLOCK DIAGRAM OF VCR SECTION

. DESCRIPTION OF VCR SECTION

SCHEMATIC DIAGRAM . PRINTED WIRING BOARD ASSEMBLIES . . .

REPLACEMENT PARTS LIST

.

PACKING OFTHESET

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

........

.......

........:.....

......

.....

*

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

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

65 69 73

82 99

101

111 119 129 167

WARNING

The chassis in this receiver is partially hot. Use an isolation transformer between the line cord plug and power receptacle, when servicing this chassis. To prevent electric shock, do not remove cover. No user qualified service personnel.

-

serviceable parts inside. Refer servicing to

SHARP CORPORATION

n

OUTLINE OF THE PRODUCT

Power Source:

Power Consumption:

Receiving Broadcast Standard:

Receiving Channel:

Receiving System:

Antenna Input Impedance:

Video Signal:

Audio Signal:

Temperature:

Di

mentions

n

TV SECTION

n

VCR SECTION

Weight (Approx.):

Cabinet Material:

(Approx.):

Accessories:

Viewing Area:

Picture Power:

Speaker Output:

Picture Tube:

SPECIFICATIONS

11 O-240 VT-3418X: 77 i/T-5118X: 98 W

PAL System B/G, I, D/K, M VHF;

UHF;

Sound;

Colour;

VHF/UHF;

Input;

output;

Input;

output;

Operation;

Strege;

VT-3418X: 392

VT-5118X: 523mm(W)x488mm (H)x483

VT-3418X: 14.2

VT-5118X: 26.1

Plastic

0

Operation Manual

Cl

Infrared Remote Control Unit

0

Dry Batteries, Type AA (x 2

0

Guarantee Card

VT-3418X: 33.54 VT-51 18X: 50.8 VT-3418X: 22.0 kV VT-5118X: 25.0 kV VT-3418X: 1.5 VT-51 18X: 1.5

Type;

Heater;

Focus;

V AC,

VT-3418X: 6.3 V, 300

50/60

Hz

w

lA-S20 E21-US83

5.5/6.0/6.5/4.5

PAL /

SECAM / NTSC

75

ohm Unbalanced (DIN)

O-5-2.0

1 .O

-

-8db/lkohm(RCA)

VT-3418X: VT-5118X: VB51JFCGlX/E2

VT-5118X: 6.3 V, 680

High

Vp-p / 75 ohm (RCA)

Vp-p /

8 d b /

47k

5”Cto40”C

- 20°C

to

mm

(W)

kg kg

cm Diagonal Measurement

at

W at Max. (8 cm Round Dynamic x 2

Bi-Potential Electrolstatic

MHz

75 ohm (RCA)

ohm (RCA)

60°C

x

371

mm

PCS)

800 ,&

1100 fi

VB370BVBKl

Beam Current

mA

(H)

x

395

U-S (Tint Tube)

(TintTube)

mm

(D) (D)

PCS) PCS)

Outline:

Format:

Video Recording System :

Luminance: FM Recording

Chrominance: Low Frequency Converted Direct Recording

Video Signal System: PAUSECAM/NTSC 3.58

Cassette Tape:

Tape Width:

Tape Speed:

Recording/Playback Time:

Note: The antenna must correspond to the new standard DIN 45325

antenna with 75 ohm connector.

VHS

Video System

VHS PAUNTSC

Rotary Slant Azimuth 2-Head Helical Scan System

VHS

Type Video Cassette Tape

12.7

mm PAL;

NTSC;

SP; LP; EP;

23.39

mm/s

33.35 mm/s

Max.

240 min

Max.

480 min

Max.

480 min

Colour

Standard

MHz

(SP), 11.70

(SP),

(with

Video Cassette Recorder

Colour

mm/s

11.68 mm/s

E-240)

E-240,

T-160, NTSC

(LP)

(LP*PB

PAL only)

only)

only), 11

(IEC 169-2)

-12

mm/s

(EP)

for combined UHF

IMPORTANT SERVICE NOTES

Maintenance and repair of this receiver should be done by qualified service personnel only.

SERVICING OF HIGH VOLTAGE SYSTEM AND

PICTURE TUBE

When servicing the high voltage system,

remove static charge from it by

connecting a 10 k ohm Resistor in series with an insulated wire (such as a test probe) between picture tube

dag

and

2nd

anode lead. (AC line cord should

be disconnected from AC outlet.)

1.

Picture tube in this receiver employs integral implosion protection.

2.

Replace with tube of the same type number for continued safety.

3.

Do not lift picture tube by the neck.

4.

Handle the picture tube only when wearing shatterproof goggles and after discharging

the high voltage completely.

X-RAY

This receiver is designed so that any X-Ray radiation is kept to an absolute

minimum. Since certain malfunctions or servicing may produce potentially hazardous radiation with prolonged exposure at close range, the following precautions should be observed:

1. VT-3418X:

VT-5118X:

2. VT-3418X:

VT-5118X:

-‘.

If there is a possibility that the high voltage fluctuates as a result of the repairs, never

forget to check for such high voltage after the work.

3.

DO not substitute a picture tube with unauthorized types and/or brands excess X-ray radiation.

When repairing the circuit, be sure not toincrease the high voltage to more than

25.3 kV,

When repairing the circuit, be sure not to increase the high voltage to more than

29.3 kV,

To keep the set in a normal operation, be sure to make it function on

22.0 kV

been factory

To keep the set in a normal operation,

25.0 kV + 1.5 kV

factory -Adjusted to the above-mentioned high voltage.

(at beam 0 +) for the set.

+

1.5 kV - 2.0 kV

-Adjusted to the above-mentioned high voltage.

(at beam

1100 ,uA)

800 ,&)

in the case of the set. The set has been

in the case of the set. The set has

be sure to make it function on

which may cause

BEFORE RETURNING THE RECEIVER

Before returning the receiver to the user, perform the following safety checks.

1.

Inspect all lead dress to make certain that leads are not pinched or that hardware is not

lodged between the chassis and other metal parts in the receiver.

2.

Inspect all protective devices such as non-metallic control knobs, insulating fishpapers,

cabinet backs, adjustment and compartment covers or shields, isolation resistorcapacity networks, mechanical insulators etc.

LOCATION OF USER’S CONTROL

CONTROL PANEL

INSIDE THE COVER

POWER BUTTON

\

VlDEO INPUT JACK

AUDIO INPUT JACK

I

VIDEO AUDIO

STOP/EJECT BUlTON

PLAY BlJlTON

FF

(Forward video search)

BUTTON

mh

I

;;;rF$verse

VOLUME UP/DOWN CHANNEL UP/DOWN

r

video search)

BlJlTONS

BUlTONS

I

SENSOR AREA FOR REMOTE CONTROL

VT-341 8X

o I

I

p

MAIN POWER SWITCH (0 I)

q

POWER CORD

ANTENNA IN TERMINAL AUDIO OUT TERMINAL

VIDE;

OUT TERMINAL

I

o

. . .

v

JL

_1

-

VT-51

18X

MAIN POWER SWITCH (0

ANTENNA IN TERMINAL AUDIO OUT TERMINAL

VIDEO OUT TERMINAL

4

.

P;;WER

I)

CORD

I

-

Remote Control Battery Installation

The remote control lets you operate this product at a distance. Just aim the front of the remote control at the photoreceptor window situated on the front panel and press the appropriate buttons.

Inserting the Batteries

The remote control operates on two R6 (UM/SUM-3, AA)

1.5

volt batteries (included). If the remote control does not operate or fails to function normally due to weak batteries, new batteries can be purchased at

electronics or camera stores.

Open the battery cover. (Remove any old bat-

Battery

cover

0

teries that may be in the remote control.)

Insert new batteries and match their polarities

@

( + and -) with the markings inside the compartment.

@

Replace the cover.

Location

POWER ON/OFF button (0 EJECT/LOAD button

CHANNEL SELECT

buttons

DISPLAY button

DPSS(O, @)I

SLOW@, 0) buttons

SP/LP*EP

REC

button

REW/Reverse -

Video Search button

TIMER ON/OFF button CONFIRMING TIMER

PROGRAMME button

of Controls

I)

button

-

666

--686

SHARP

VIDEO

-TV

C-COCK

r

I

/--

MUTE button

CHILD-LOCK button

r

1 r r

-

CHANNEL UP/DOWN&&tons

(TRACKING buttons)

VOLUME ADJUSTMENT

buttons SLOW PLAYBACK button COUNTER RESET button

STOP button

F*ADV

button

-

PAUSE/STILL button

FF/Forward

Video Search button

PLAY button

-,

+ buttons PROGRAMME button

MENU button

SET button

5

c

VT-341

8X

VT-5118X

n

TV SECTION

DISASSEMBLY AND REASSEMBLY

I. VT-3418X:

VT-51

18X: Remove the nine screws off the rear cover.

Disconnect the F and G connectors from the main

2.

3.

Remove the screws off the video unit and take out the unit.

4.

Remove the two screws from the main

VT-341

Remove the eight screws off the rear cover.

PWB.

PWB

and separate the

8X

rr

PWB

from the video unit

VT-51 18X

6

n

CONNECTIONS FOR SERVICING

Use the following extension cables in servicing the VCR unit taken out of the set.

Extension cables:

l

Connecting the extension cables

(1)

Between AB (TV unit) and JA Connect the cable

(2)

Between AL (TV unit) and LA (LED unit):

Connect the cable

Part codes

QCNW-3778CEZZ

QCNW-3780CEZZ

QCNW-3778CEZZ, QCNW-3780CEZZ

(AV

jack):

between the AB plug and the AB socket.

between the AL plug and the AL socket.

Extension cable: QCNW-3780CEZZ

Extension

5.

6.

cable: QCNW-3778CEZZ

Remove the CRT

the main

PWB

PWB, degaussing

upright.

Reconnect the CRT

PWB.

power switch remote control

*

VT-51 18X

Only for

~oUnd0

coil connector G, and front power switch remote control

Put the main

PWB,

speakers and

PWB.

PWB

and the VCR unit together as shown below. Keep the front

degaussing

coil connector G off position.

Place

(Only for VT-341 8X)

Power

SW+I/C

/

PWB

DA

\

‘LINE FILTER PWB

,

VT-341

8X

VT-5118X

I I

ADJUSTMENT

TV ELECTRICAL CIRCUITRY

VIDEOKHROMA

I

1.

CRT Cut-off Adjustment

Adjusting Point Cl

R853:

Cl

R859: Cl R865: El T602: Screen control (a pat-t of T602) Cl R857: !Il

R863:

Note: Prior to this adjustment, warm up the unit with the beam current of more than

7004 (VT-51 18X)

1.

Receive “MONOSCOPE PATTERN” signal with

pattern generator.

2.

Set Red bias control at

Set Green bias control at Set Blue bias control at Set Green drive control at CENTER Set Blue drive control at CENTER

3.

Set the control at the “NORMAL” position that

Contrast is MAX Brightness is CENTER

“v”

keys.

4.

Set the Screen control at

5.

Turn on

line position.

6.

Connect the oscilloscope to

Adjusting Conditions

Red Bias control

Green Bias control

Blue Bias control

Green Drive control Blue Drive control

for more than 30 minutes.

MIN

(O/l 0) position.

MIN

(O/l 0) position.

(60), Colour

(0)

using control, “A” and

MIN

51401

(Service switch) at the horizontal

6OOfl (VT-3418X)

(O/l 0) position.

(5/l 0)

position.

(5/l 0)

position.

is CENTER

(O/l 0) position.

TP852

(Red Cathode).

(0)

OFTHE

ADJUSTMENT

1.

Adjust the Sub-Brightness control

the blanking pulse on oscilloscope is 10 +

2.

Slowly turn the Screen control clockwise and stop

I

an

it where the horizontal raster appears slightly, in one of the three

3.

Carefully adjust the Bias controls of the other two

colours

4.

Turn the Screen control counterclockwise until

the horizontal raster disappears, and stop it.

untii the horizontal raster becomes white.

Adjusting Procedures

colours.

(R425)

so that

lVp-p.

2.

Sub-Contrast Adjustment

Adjusting Point

I

0 R421:

Sub-Contrast control

I

Note: Prior to this adjustment, warm up the unit with the beam current of more than

7004 (W-51 18X)

1.

Receive “MONOSCOPE PATTERN” signal with

pattern generator.

2.

Set the Contrast and Brightness controls at MAX

position.

3.

Connect DC

TP602@.

(Full scale: 3

for more than 30 minutes.

milliammeter

mA)

600@ (VT-3418X)

to

TP6019

and

1.

Adjust Sub-Contrast control so that the beam

current becomes

5118X).

I

0.8

mA

(VT-3418X) /

8

1 .l mA

(VT-

VT-341

8X

W-5118X

VIDEOICHROMA

3.

White Balance and Back Ground Adjustment

Adjusting Point

El R857:

Cl

Cl R421:

Vote:

srior 5eam 7004 (VT-51 18X)

I. Receive “MONOSCOPE PATTERN” signal with

pattern generator.

!.

Set the Contrast and Brightness controls at MAX

position.

5.

Connect beam ammeter to

(Full scale: 3 mA)

Green Drive control

R863:

to this adjustment, warm up the unit with the

current of more than

Blue Drive control

Sub-Contrast control

6004

for more than 30 minutes.

TP601

(VT-3418X) I

and

TP602.

ADJUSTMENT (Continued)

1.

Adjust the Sub-Contrast control so that the beam

current becomes

5118X) (rough adjustment).

2.

Adjust the Green Drive control and Blue Drive

control so that the colour temperature is at

10900K.

l

High beam:

0.8

mA

1.1

mA(VT-5118X)

3.

Adjust the Contrast control and Brightness

control so that the beam current is

200,&,

at

9300°K.

go back to “CRT CUT-OFF ADJUSTMENT” and repeat the adjustment.

(X = 0.285,

0.8

mA

(VT-3418X) /

(VT-341 8X)

and check that the

If the temperature is not at

Y = 0.292)

colour

1 .l mA

temperature is

(VT-

approx.

9300”K,

4.

Sub-Tint Adjustment

Adjusting Point

0 R1882:

1.

Feed

with

2.

Connect oscilloscope to

3.

Set the Tint control at the CENTER

4.

Set Service switch

to cut off the Y-signal.

1

j.

Bell Filter Adjustment

Adjusting Point

0 T1802:

1.

Receive

bar generator.

2.

Connect oscilloscope to TP1801 with the

following settings.

l

Range:

l

Sweep Time:

l

Probe:

Sub-Tint control

“NTSC

COLOUR BAR” signal to video in jack

colour

bar generator at the AV mode.

TP853 (B - Y).

51401

at the Video Cut position

Bell Filter

“SECAM

COLOUR BAR” signal with colour

0.05V / 20psec /

l/l 0

div. AC

div.

(3OpF,

1

OMQ

(0)

position.

or more)

1.

Adjust

approx. 3Vp-p.

2.

Adjust Sub-Tint control

waveform is as shown in figure below.

3.

Return

1.

Adjust the Bell Filter

output and blue amplitude.

Colour

51401

Same

B-Y

CY G Mg

control key to obtain the output of

(R1882)

to CENTER (normal position).

level

y

/’

/-

.)

.

W Y Cy

-

(B)

R

B

‘c_

/@(

-

GMg

(T1802)

output will have the same

Same amplitude

so that the output

_.z_‘-

-

R B

so that the red

//-

(R)

r-

9

VIDEOICHROMA

ADJUSTMENT (Continued)

Adjusting Conditions

6.

PAL

Adjusting Point

Cl

0 T1801:

Note: Before this adjustment, the

1.

Receive “PAL COLOUR BAR” signal with pattern

generator.

2.

Connect the following resistance matrix to pins 3

and 4 of the connector oscilloscope is connected.

TP853 (K)+

3.

Set the Service switch

position to cut off the Y-signal.

Chroma

R1806:

adjustment must have been completed.

Adjustment

1 H Delay Amp. control 1 H Delay Phase control

(K),

to which an

22 kSZ

To oscilloscope

Resistance Matrix

51401

at the Video Cut

PIFIAFTIAGC

I

1.

Adjust the

waveform of

1.5

vp-p.

2.

Adjust

waveform shown in Fig. a is corrected to that shown in Fig.

3.

Return

Adjusting Procedures

Colour

control key so that the output

colour

difference signal becomes

R1806

and

T1801

so that the output

6.

51401

to CENTER (normal position).

W Y Cy G Mg R B

--#--.

-

u

--*m---w

.-

---m-

r

-

mm --m-w

1

Figure a. Waveform before the adjustment

1

1.5 vp-p

I

7. SECAM

r

Adjusting Point

0 11803:

1. Receive”SECAM

bar generator.

2.

Connect oscilloscope to

following settings.

l

Renge:

l

Sweep Time:

Killer Adjustment

SECAM Killer

COLOUR BAR” signal with

lV/div.

(Adjust vertical position proper

20psec /

DC

div.

control

TP1802

colour

with the

,lY.)

IO

Figure 6. Waveform after the adjustment

1.

Adjust

TPl802

T1803

to obtain maximum DC voltage at

(approx. 9.5V).

VIDEOKHROMA

Adjusting Conditions Adjusting Procedures

8.

R -Y/B -Y Discriminator Adjustment

Adjusting Point

0 T1804:

0 T1805:

1.

Receive “SECAM COLOUR BAR” signal with colour

bar generator.

2.

Connect the oscilloscope (with two

TP851 (R - Y)

on the CRT Socket Unit of the set.

l

Renge:

l

Sweep Time:

3.

Set service switch

’

to cut-off the Y-signal.

4.

Set both the Contrast and Brightness controls to

their maximum postions.

R - Y Discriminator B - Y Discriminator

and the

TP853 (B - Y),

lV/div.

20psec /

51401

DC

div.

at the Video Cut position

channecls)

both located

ADJUSTMENT (Continued)

to

1.

Adjust

output level with will be the same as that with

100%

* Connect capacitor (0.001

2.

Set service switch

T1804 (R - Y)

of saturation. (A =

TP853,

thus to prevent noise interference.

and

colour

51401

TP851

T1805 (B - Y)

control set at minimum

colour

B)

,xF)

to the canter position.

so that DC

control set at

to

TP851

and

TP853

*

Same

B

DC

DC output level

OV

11

VT-341 8X VT-5118X

DEFLECTION LOOP ADJUSTMENT

Adjusting Conditions

1.

Focus Adjustment

Adjusting Point

0 T602: Focuscontrol (a part of

1.

Receive “MONOSCOPE PATTERN” signal.

2 Set the Brightness and Contrast controls at

NORMAL position.

2.

Horizontal Center Adjustment

Adjusting Point

Cl

RI

602: Horizontal Center control

Note: This adjustment should be performed after

the purity and convergence adjustments.

1.

Receive “MONOSCOPE PATTERN” signal.

T602)

Adjusting Procedures

l

During the adjustment, keep the unit facing the east.

1.

Adjust Focus control (a part of

focus at the central area of CRT.

l

During the adjustment, keep the unit facing the east.

1.

Adjust

picture is at the position which gives the relation

ofA=B.

R1602

so that the horizontal center of

+

I

A-

l

T602)

Adjust point

-)B

to have best

4

3.

Vertical Linearity Adjustment

Adjusting Point

Cl R526:

1.

Receive “MONOSCOPE PATTERN” signal.

4.

Vertical Size Adjustment

Adjusting Point

Cl R503:

1.

Receive “MONOSCOPE PATTERN” signal.

2.

Set the Brightness and Contrast controls at MAX

position.

Vertical Linearity control

Vertical Size control

(+=

I

l

During the adjustment, keep the unit facing the east.

1.

Adjust

picture is at best point.

l

During the adjustment, keep the unit facing the east.

1.

Adjust

the same size as horizontal size. . V-SIZE

R526

so that the vertical linearity of

R503

so that the vertical size of picture is at

8%

TYP

12% MAX

12

DEFLECTION LOOP ADJUSTMENT (Continued)

VT-341 8X VT-5118X

Adjusting Conditions

5.

Vertical Centering Adjustment

Vertical Center Adjust switch

This adjustment should be performed after

the purity and convergence adjustments.

“MONOSCOPE PATTERN” signal.

ADJUSTMENT OF THE IF CIRCUIT

Adjustment of the RF

Test point

Adjusting point

TP201 @I (GND) TP201 0

VROOl (AGC

I

AGC

(Video Output)

control)

Adjusting Procedures

l

During

the’adjustment,

1.

Adjust

idential to CRT geometrical vertical center.

5501

so that the picture’s vertical center is

keep the unit facing the east.

Adjustment of the AFT

Measuring instrument Signal generator

Mode

Input signal

Test point

I

Adjusting point

Oscilloscope

EE

I

PIF

frequency

Colour bar signal TP201 @ (GND)

TP201 @

I

TOO2

I

(Video Output)

(AFT coil)

uniwave

(70

dBp)

1.

Receive the

strength: 80

2.

Observe the video output terminal waveform

on the oscilloscope. Adjust

in the IF pack until the noise disappears from

the oscilloscope screen and the waveform

nearly comes into sync.

Just before shrinking

colour

dBp).

bar signal (input field

Figure

VROOl (AGC

1.

control)

Specification

1.

Receive the colour bar signal (input field

strength: 70

2.

Using the signal generator, feed the

frequency tuner IF output terminal.

3.

Set the tuning switch to the VHF or UHF

position. Keep the tuning button depressed until the beating on the oscilloscope screen be minimum.

4.

Set the tuning switch on the normal position.

Adjust oscilloscope screen be minimum.

TOO2

-

I

dBp).

(38.9

MHz) signal (sinewave) to the

(+)

or

(AFT coil) so that beating on the

PIF

(-)

13

I

Figure 2. IF Pack

FUNCTION OF MAJOR

Take-up pole

Drum

Full erase head

Supply pole base

Tension arm

MECHANICAL PARTS

base

ass’y 2

ass’y

I

ass’y ass’y

Brake shifter w

I

Q,

\

24 AHC(Automatic

0

@/Cheadass’y

/

Head Cleaner)

(TOPVIEW)

@Camztch

h

Ass’y

23

Dew sensor

AJ

Loading motor Master cam

Pinch roller lever Relay shifter lever

Capstan D. D. motor

Reverse guide

Take-up reel disk

Video lever

ass’y

search brake

Back tension lever

Main supply brake

No.

Full erase head

1.

Erase the whole records on the tape in the recording mode.

3.

Tension arm

Detects the tension of tape while running, and brakes

the supply reel disk via the tension band.

4.

Brake shifter

,Set the position of brake or the like in accordance with

the modes such as stop and playback.

5.

Back tension lever Brakes the supply reel disk to a certain degree to .

’

prevent tape slackening during “half-loading”,

“loading” and “shifting from playback to video search rewind”.

7.

Main supply brake lever Brakes the supply reel disk to prevent tape slackening

when the unit is stopped in fast forward or rewind

mode.

ass’y

Function

ass’y

No.

Reverse guide

13.

Pulls out the tape in the video search rewind mode,

and controls the tape drive train height with the upper

and lower guides. Relay shifter lever

T5.

Transmits the operation of the master cam to the brake shifter, and operates the reverse guide.

Pinch roller lever

16.

Press-fits the tape to the capstan during tape running. The right protrusion switches the clutch of the cassette housing control assembly in “tape eject”, and makes the mechanism eject the tape.

Master cam

17.

Turns clockwise during loading, and counterclockwise during unloading, and moves the shifter or the like in accordance with each mode.

Loading motor

18.

A motive power which drives the mechanism. It transmits the power to the master cam and cassette housing control assembly via the belt.

Function

ass’y

9.

Main take-up brake lever Brakes the take-up reel disk to prevent tape slackening Rotates synchronously with the master cam, and

when the unit is stopped in fast forward or rewind detects the position of each mode by means of the

mode.

11.

Video search brake lever

It is in contact with the take-up reel disk normally, and brakes it to a certain degree. It applies larger brake in unit. This element is activated, when it senses

the video search rewind mode.

Cam switch

19.

internal switch. Dew sensor

23.

An element which detects condensation inside the

condensation, to interrupt the mechanism.

14

FUNCTION OF MAJOR

MECHANICAL PARTS

Slow brake lever

Loading relay gear

Capstan D. D. motor

Reel belt

Relay gear drive lever

I

x

3

o=

@-

(BOmOM

VIEW)

IO

Supply loading gear

/o

Reel sensor

No.

Slow brake lever Gets in contact with the capstan the master cam in the slow still mode, and brakes it to a certain degree.

Capstan

A motive power which runs the tape. It transmits the

power via the reel belt.

Reel belt

Transmits the power to run the tape to the reel pulley.

Brake solenoid

5.

Adsorbs and holds the brake shifter in the fast forward and rewind modes, and releases it in the stop mode.

Reel pulley

6.

Transmits the power of the capstan reel disk via the reel idler.

D-D.

7

d

motor

Brake

Function

solenoide

D.D.

motor linking to

D.D.

5

()

motor to the

d

Reel pulley

No.

7.

9.

10.

.

11.

Function

Reel sensor

An element which sheds the light onto the reflection

plate affixed to the bottom side of the reel disk, and detects the rotation of the reel disk through receiving the reflected light.

Take-up loading gear Shifts the take-up pole base and guide roller via the loading relay gear, and applies the tape around the

durm

assembly, as well as transmits the power to the

supply loading gear.

Supply loading gear Shifts the supply pole base and guide roller via the

take-up loading gear, and applies the tape around the

drum assembly.

Relay gear drive lever Transmits the movement of the master cam to the take-up loading gear via the loading relay gear.

15

ADJUSTMENT, REPLACEMENTAND

ASSEMBLY OF MECHANICAL UNITS

Here we will describe a relatively simple service

work in the field, not referring to the more

complicated repairs which would require the use of

special equipment and tools (drum assembly

We are sure that the easy-to-handle tools listed below would be more than handy for periodical maintenance to keep the machine in its original working condition.

replacement, for example).

TOOLS NECESSARY FOR ADJUSTING THE MECHANICAL UNITS

The following tools are required for proper service and satisfactory repair.

These Jigs are used for checking and adjusting the reel disk height

A/C Head Tilt Adjusting Jig

6

Cassette Torque Meter

Tension Gauge (3009) .

7

Tension Gauge

Hex Wrench (0.9mm)’

Hex Wrench (1.2mm)

8

Hex Wrench (1.5mm)

Alignment Tape (PAL)

9

Alignment Tape

JiGVHT-063

JiGSG0300

(2.Okg) JiGSG2000

JiGHW0009 AE

JiGHW0012

JiGHW0015

VROCPSV

(NTSC)

VROATSV

VRONBZGS

CZ

BF

BS.

AE

11

w

<

f4sz$zg

These Jigs are used for checking and

for checking and adjusting the torque of take-up for measuring

There are two gauges used for the

tension measurements, 300 g and

2.0

kg.

These Jigs are used for loosening or tightening special hexagon type screws.

This tape is especially used for

electrical fine adjustment.

10

Drum Replacing Jig

JiGDT-0001

BG

This is used for replacement of the VCR’s upper drum.

16

No.

11

Tension Gauge Adapter

Jig Item

Part No.

JiGADP003

Code

BK

Configuration

ecih

Remarks

This Jig is used with the tension gauge. Rotary transformer clearance adjusting jig.

Special Bladed Screwdriver

12

Tension Band and Plate

13

Adjusting Jig

14

Torque Driver JiGTDl200

Box Driver

15

Reverse Guide Height Adjusting

16

Jig

JiGDRiVERH-4 AP

JiGDRiVER-

JiGDRiVER

JIGRVGH-F18 BU

1

10-7

O-4

BM

CB

AS

AV

This screwdriver is used for adjusting the guide roller height.

This Jig is used for adjusting the tension band and tension plate.

This is used to screw down resin-

made parts: the specified torque is 5 kg-

This Jig is used for height adjustment of the A/C head and X-

position.

0

&@

This Jig is used for height adjustment of the retaining guide.

This Jig is used for height adjustment of the reverse guide.

17

MECHANICAL PARTS REQUIRING PERIODICAL INSPECTION

Use

the

following

table as a guide to maintain the mechanical parts in good operating condition.

;uide

roller

ass’y

;upply

impedance roller

;upply

impedance roller

)nner

hole and shaft)

;upply

impedance roller flange

Retaining guide

slant

pole

Video head (upper drum

Full-erase head

AIC

head

Lower drum

Capstan

Pinch roller

D.D.

ass’y

Motor

ass’y)

1000 1500 2000

Cl

q 0 0

0

0 q 0

q

q q q q

q 0 q q

q q q 0

q

00

q

0 Cl

q 0 q

cl

q q

cl cl q 0

q cl q 0

q Cl q 0

Possible symptom encountered Remarks

Abnormal rotation or significant vibration requires replacement.

q

Lateral noises

. Head occasionally blocked

Poor S/N ratio, no color

0

Poor colour, beating

0

Sound too small or distorted

Poor flatness of the envelope with alignment tape

No tape running, uneven color

No tape running, tape slack

Clean with pure high quality isopropyl alcohol.

Clean tape contact part

with the specified cleaning

liquid.

Clean tape contact area with the specified cleaning liquid.

Reel belt

Loading belt

Cassette loading belt

Tension band

Loading Motor 0

AHC

(Automatic Head Cleaner)

Reel block*

* See the table below for servicing the reel block parts.

SupplyTTake-up reel disks

Video search brake lever

Idler gear

Reel Pulley

ass’y

cl

q

cl 0

0 0

IJA

CIA

A 0 No tape running, tape slack

No tape running, tape slack, no

0

fast forward/rewind motion

0

Cassette not loaded or unloaded

Lateral image swing

0

Cassette not loaded or unloaded

See the chart below.

0

No tape running

0

00

Clean rubber and rubber

contact area with the

specified cleaning liquid.

Replace the roller of the cleaner when it wears down. Just change the

AHC

roller assembly for

new one.

Clean with pure high quality isopropyl alcohol.

Main

supplyfiake-up

NOTE:

brake levers

0:

Part replacement.

0 Tape slack

Cl :Cleaning (For cleaning, use a lint-free cloth dampened with pure isopropyl alcohol).

A:

Oil refilling (The indicated point should be lubricated with high quality spindle oil every

1000 hrs).

If the reading is out of the specified value, clean or replace the

18

par-t.

REMOVAL AND REASSEMBLY OF CASSETTE HOUSING CONTROL ASSEMBLY

l

Removal

1.

Set the cassette ejected condition in the cassette

eject mode.

2.

Unplug the recorder from the main source.

3.

Follow the procedures below in the specified

order.

a) Remove the cassette loading belt

b)

Disconnect the

c)

Remove the cassette housing installation

screws

d)

Slide and pull out the cassette housing control

assembly @ upward.

0.

FFC

(Full Flat Cable)

w

49

4

n

0. a.

When the detached, tuck it as in the figure so that it is kept free from grease.

ble)

loading Note the

belt is

4.

In removal and reassembly, take care not to hit

the cassette housing control assembly or tools against the guide pin, drum, or the like thereabout.

5.

Place the unit in the eject mode in removal or

reassembly of the cassette housing control assembly.

6.

Load the cassette once onto the cassette housing

control assembly after reassembly. (If the cassette housing control assembly normally operates after this, the phases of mechanism and

the cassette controller are accurately adjusted

after ej

ecti

on.)

MECHANICAL OPERATION CHECK WITHOUT

When power is on, the general operations of the mechanism can be checked without a cassette.

Check video search rewind and rewind, rotating

the take-up reel disk @ by hand (in either

normal or reverse direction). If it is not rotated, the reel sensor works to shift the mechanism to the eject mode. When the stop button is pressed, the mechanism

does not stop at a normal stop position. It shifts to the eject mode and stops.

When the stop button is pressed in the playback,

video search rewind, and video search forward

modes, the supply reel disk 8 keeps on rotating

for several seconds for elimination of tape slack

in the course of shifting to the eject mode. In such a case, rotate the take-up reel disk somewhat by hand, and the supply reel disk stops, which can reduce the working time.

CASSElTE

following points.

@

insert the tab of

the Cassette housing

Figure1 -1.

Reassembly

.

Before installation of the cassette housing control assembly, place the unit in the stop mode with the power on, then unplug the power cord. (The main body is placed in the eject mode.)

&.

Follow the procedures for removal in the reverse

order.

Notes:

1.

Be sure to unplug the power cord in removal and

reassem blv.

2.

Keep the cassette loading belt free from grease.

In case of its adhesion, clean the belt.

3.

In using a magnet screw driver, be sure to keep it away from the A/C head, FE (Full Erase) head, or the drum.

control assembly to the mechanism chassis.

REPLACEMENT OF WORM WHEEL

ASSEMBLY

Cassette housing frame

FO

/

Figure

Worm wheel

l-2.

Cassette switch

Worm bracket

tight screw

ass’y

19

VT-341 W-51

18X

8X

l

Removal

1.

Unsolder the cassette switch connectors (No.

17)

from the start sensor

Cassette switch

connector

2.

Lift the start sensor

sensor

PWB

fixing hooks inward.

PWB.

Start sensor

Figure

l-3.

PWB

pressing the two start

Start sensor

PWB

16,

5.6Place the slider pin just above the worm wheel

assembly (Figure l-7). (The retainer of the slider is locked at two positions. So unlock it as in the Figure

1-8.)

Pull out the worm wheel assembly toward you pressing the switch lever upward. (Figure

Phase

ge

shaft

Tally mark

‘%ut

washer

Figure

l-7.

l-7)

itch lever

Figure

l-4.

3.

Unscrew one B tight screw to detach the worm bracket. Note:

The worm shaft bearing can easily come-out of

position. So be careful not to lose it.

-Worm bracket

LWorm

4.

Remove the worm shaft assembly, pulley, and

Figure

wheel

l-5.

ass’y

cassette loading belt all from the cassette

housing frame

Worm shaft a

(R).

Cassette housing

frame

(R)

the

(L)side

/-Slider

Cassette housing frame

(R)/(L) side

Figure

l-8.

Reassembly Turn the phase gear clockwise until the slider comes to a halt in the cassette insertion direction. (See the Figure

l-9.)

Insert the set up worm wheel gear assembly into

the cassette housing frame

(R),

matching the

mark on the phase gear with the mark on the

worm wheel gear. Detach the cut washer on the

phase gear assembly and the phase gear for

easier installation of worm wheel assembly.

Note: Make sure that the slider pin is in the groove of

the drive gear arm.

Figure

l-6.

20

Xut

Phase

/

washer

wheel

arm

VT-341 8X VT-5118X

Tighten one B tight screw.

Note: Do not over-tighten the B tight screw (no more

than

5.0 +, 0.5

of the screw hole at the resin-made boss can be broken. Place the start sensor housing frame Note: Check that the switch connectors (No. in the cassette switch mounting hole.

Finally resolder the cassette switch connector to

the start sensor

kg-cm), because the lower threads

PWB

on the cassette

(R).

16, 17)

are

PWB.

(a)

Install the pulley and the cassette loading belt on

3.

Figure

l-9.

b)

the worm shaft assembly. Couple the clutch to the clutch lever. And mount them together in the cassette housing frame

(R).

Note:

Keep in mind that the clutch switching lever

should be in the correct position.

mechanism might malfunction if the lever is

slightly out of position. (See page

Cassette housing frame

Worm wheel

ass’y

(R)

22.)

Cassette loading belt

The

k

-Cassette housing

frame(R)

shaft bear

REASSEMBLY OF DRIVE GEAR

rPillar

Drive gear spring

Drive gear arm

ing

(R

,,

1

Drive gear arm

(4

Drive gear spring

(R)

0

Worm wheel square hole

I

LReciprocating spring

Figure

l-1 0.

4.

Attach the worm bracket to the worm shaft

assembly. Place them onto the boss on the cassette housing frame

Note:

Insert 0 before screwing into Q and

Figure l-l

(R).

1

Cassette housing frame

P

r-3

1.

0.

(R)

21

spring-shaft

gear arm

(Drive gear bottom view)

(W

Figure

l-1 2.

1.

Pass the tip of the drive gear spring

(R) 0

through the square hole of the drive gear

hook the spring in position. Hook one end Q of the reciprocating spring to the catch of the drive gear

(R).

Hook the other end 0 of the reciprocating spring to the catch of the worm wheel. Insert the pillar @ of the drive gear

(R)

into the square hole of the worm wheel. Turn the worm wheel somewhat counterclockwise for insertion of the worm wheel to the drive gear

(R),

because

the reciprocating spring is at work.

(R)

to

VT-341

8X

W-5118X

REPLACEMENT OF CASSETTE LOADING BELT

Cassette

1.

Remove the start sensor

2.

Remove the worm shaft assembly

3.

Replace the cassette loading belt @ with a new

Notes:

1.

2.

3.

housing frame

bracket 0 from the cassette housing frame

(R)

Figure

l-1 3.

PWB @

Worm bracket

and worm

(R).

0.

one.

Do not over-tighten the B tight screw which holds the worm bracket in position. The specified torque is

5.0 2

0.5

kgcm.

Make sure that the cassette loading belt is free from grease.

If stained with grease, clean the belt with the cleaning liquid. Perform checking of the clutch switch lever for proper action.

CHECKING THE CLUTCH SWITCH LEVER

l

Checking

Place the mechanism in the cassette eject mode

when removing and attaching the cassette

housing from and to the mechanism chassis. Make sure enough that each part in the cassette housing such as the clutch switch lever is in position. If not, it causes malfunction. Note: Figure

the cassette eject mode.

l-14

shows the position of each part in

Figure l-l

4.

1.

First make sure that the tip of the switch lever is held at the rib of the drive gear

2.

Check that the rib of the cassette housing frame

(R)

and the concavity of the clutch lock lever are

(R).

engaged.

Finally be sure that the relationship between the

3.

clutch lever and the clutch, as well as between the clutch and the pulley, are correct as in the

Figure l-1

5.

.

Check that the clutch is engaged

with the pulley through the coupling.

0

Resetting

Figure l-l

5.

Take the following steps to reset the clutch if it is unlocked or if the switch lever and the clutch lock lever are unlocked.

LDrive

gear

Shift the slider by turning the coupling in the

1.

(R)

lever

LClutch

l-1

lock lever

6.

Rib of cassette housing frame

Figure

arrow direction (clockwise) until the slider pin is at the bottom of the slider groove as shown in

the Figure l-16. (The loading mode)

Note: Note that the slider is mechanism. housing frames

Unlock the locks on cassette

(L)

equipped’with

and

(R)

a lock

side before shifting the slider. When the position is set as shown in the Figure 4-

16, push the clutch release lever in the direction

of the arrow by hand until the clutch lock lever

becomes tightly locked by the rib of the cassette housing frame

(R).

Then turn the coupling counterclockwise until

the slider reaches the cassette insertion opening

and the reciprocating spring is activated. Note: There is no need to unlock the slider when

shifting the slider to the cassette insertion opening. Just keep shifting the slider.

lever

(R)

22

REPLACEMENT OF LOCK RELEASE LEVER

l

Removal

1.

Place the slider in the cassette down position.

(Turn the coupling on the worm shaft clockwise until the slider is in the cassette down position.) Note: Before shifting, unlock the slider.

2.

Slightly widen the cassette housing frames

and

(L)

to unhook the slider holders

(R)

and

the slider assembly off the grooves of the

cassette housing frames.

Pulley

(L)

(R)

of

VT-341 8X VT-5118X

4.

Remove the lock release lever from the slider

holder(R)

l

Reassembly

1.

Follow the steps for removal in the reverse order.

(See Figures

2.

Attach the lock release lever to the slider holder

00.

3.

Slide the slider holder

two catches of the slider holder

opening of the slider.

4.

Slightly widen the cassette housing frames, and

set the pins of slider holders grooves of the cassette housing frames. Note: Check if the pins of the slider holders fit the grooves of the cassette housing frames, and if the drive gear arm is sufficiently engaged with the slider holders.

5.

Turn the coupling counterclockwise until the

slider is at the cassette insertion opening.

l-17

and

l-18.)

(R)

downward so that the

(R)

and

(L)

(R)

fit the

into the

and

(L)

(4

(b)

3.

Lift the slider holder

Figure l-l

7.

(R)

upward about

2mm

the slider by pressing two catches with a thin tip screw driver. catches.

Take care not to damage the

/-Slide

off

lock catch

TO RUN A TAPE WITHOUT THE CASSETTE HOUSING CONTROL ASSEMBLY

1.

Plug in the power cord.

2.

Turn on the power switch.

3.

Open the lid @ of a cassette tape by hand.

4.

Hold the lid with two pieces of vinyl tape

5

Ined. We

0.) 7-

Set the cassette tape in the mechanism chassis.

6.

Stabilize the cassette tape with a weight @ to prevent floating. Perform running test.

Q.

Figure

l-1 8.

Note: The weight should not be more than

Figure

l-1 9.

23

500 g.

REPLACEMENT AND HEIGHT CHECKING

AND ADJUSTMENT OF REEL DISKS

Remove the cassette housing control assembly.

1.

Set the mechanism in the playback mode with no

2.

cassette tape in place. Unplug the power cord. Set the idler gear in the center (neutral).

3.

a

Removal (Supply reel disk)

Remove the tension band 0. (Take care not to

1.

deform it.)

Unscrew the screw @ and remove the supply reel

2.

retainer assembly

Release the supply reel disk catch @ and back

3.

tension lever

4.

Pull the supply reel disk upward.

Notes:

1.

Take care not to deform the tension band.

2.

Check and adjust the tension pole position. (See

page 30.)

3.

Be careful not to damage the gear and the idler

gear on the supply reel disk.

4.

Press the tension band in the direction of the

arrow for removal (See Figure

8.

0.

1-20(b)).

0

Removal (Take-up reel disk)

1.

Unscrew the screw

@

and remove the take-up

reel retainer.

2.

Release the take-up reel disk catch

3.

Pull the take-up reel disk @ upward.

Take-up reel disk

Figure

l-21.

0.

e-up reel

retainer

Note: When the tension band is pressed in the direction of the arrow for removal, the catch is hard to be deformed.

0

Reassembly (Supply reel disk)

1.

Clean the reel disk shaft 0 and apply oil to it.

2.

Release the supply reel disk catch Q and back

tension lever

3.

Install a new supply reel disk @ onto the shaft.

4.

Replace the tension band

0.

($9

around the supply

reel disk, and insert it to the hole of the tension

arm.

5.

Replace the supply reel retainer assembly @ in place, and tighten up the screw

@.

Notes:

1.

Take enough care not to deform the tension

band during installation of the supply reel disk.

2.

Be careful not to damage the supply reel disk gear, back tension lever, supply reel disk catch, or the Ii ke with tools.

5 Tension band

Q

-.

(b)

Figure

l-20.

24

Figure

l-22.

Supply reel

disk catch

0

Reassembly (Take-up reel disk) Clean the reel disk shaft 0 and apply oil to it.

1.

Release the take-up reel catch @ and video

2.

search brake lever

Install a new take-up reel disk @ onto the shaft.

3.

Replace the take-up reel retainer @ in position

4.

and tighten up the screw

0.

Note: Take care not to damage the video search brake lever.

Take-up

reel disk

Apply a thin tip driver to the arrow position in releasing for easier setting of the take-up reel disk.

Clean the reel disk shaft well, and

aoolv

oil to it.

Set the master plane releasing the reverse guide by a finger.

guide

Master

Figure

l-25.

1.

For height adjustment, press the reel disk with a

finger, and turn it right and left with a screwdriver (see Figure

2.

Check that the reel disk is lower than part A but

1-26

(a)).

higher than part B. If the height is not correct,

adjust the height adjusting screw (see Figure

26 (W.

Note: Whenever replacing the reel disk, perform the height checking and adjustment.

l-

Figure

l-23.

* After reassembly, check the video search rewind

back tension (see page

torque (see page

l

Height checking and adjustment

30).

28),

and check the brake

Note: Place the master plane onto the mechanism unit,

taking care not to hit the drum (see Figure

Setting

l-24).

Master plane

lOfO.Zmm

-

r -

1

Reel disk

I

9

(4

Slide it right and left, and check contact with

”

I f

’ y, ‘,‘, ,

L

c-c=~Z “fc &I-

‘-

]

I

0

Reel disk height

adjusting jig

/Mechanism chassis

Figure

l-24.

25

(b)

Figure

l-26.

VT-341 8X VT-5118X

CHECKING AND ADJUSTMENT OF TAKE-UP

TORQUE IN FAST FORWARD MODE

l

Remove the cassette housing control assembly.

l

Setting

Torque gauge

Set the scale to

“0”

Setting

+

Figure

/

Take-up reel disk

l-27.

CHECKING AND ADJUSTMENT OF TAKE-UP TORQUE IN REWIND MODE

l

Remove the cassette housing control assembly.

l

Setting

Torque gauge

Set the scale to

“0”

Figure

l-29.

l

Checking

Turn the torque gauge slowly (one rotation every 2 to 3 seconds) by hand in the take-up direction

700gcm

The gauge is held at

Id

Figure

l Adjustment

1.

If the take-up torque is outside the range, clean

the capstan

D.D.

motor pulley, reel belt and reel

its maximum value. (Red mark)

Take-up direction

l-28.

or more

pulley with cleaning liquid, then recheck the

torque.

2.

If the take-up torque is still out of range, replace

the reel belt.

Notes:

1.

Hold down the torque gauge so that it may not

fly off.

2.

When checking the take-up torque, do not keep

the reel disk locked for a longer time.

l

Checking

Turn the torque gauge slowly (one rotation every 2 to 3 seconds) by hand in the take-up direction

700gcm

The gauge is held at its maximum value.

Figure

l-30.

l

Adjustment

1.

If the take-up torque is outside the range, clean

the capstan

D.D.

motor pulley, reel belt and reel

or more

pulley with cleaning liquid, then recheck the

torque.

2.

If the take-up torque is still out of range, replace

the reel belt.

Notes :

1.

Hold down the torque gauge so that it may not

fly off.

2.

When checking the take-up torque, do not keep

the reel disk locked for a longer time.

26

CHECKING AND ADJUSTMENT OF TAKE-UP TORQUE IN PLAYBACK MODE

1.

Remove the cassette housing control assembly.

2. Ooen

the lid of the cassette torque meter, and

hold it with two pieces of vinyl tapes.

Open here

Cassette torque meter

Load a cassette torque meter into the unit.

CHECKING AND ADJUSTMENT OF TAKE-UP TORQUE IN VIDEO SEARCH REWIND MODE

l

Remove the cassette housing control assembly.

a

Checking

\‘I//

VSR -

0

‘/ ,,:

/

1

/

?

Push the play button to place

the unit in the playback mode.

Push video search rewind button to place the unit in the video search rewind mode.

Set value

l

Checking

1.

Check that the torque is in the range of 95 2

SP95 + 30gcm

n

Figure

l-31.

g-cm.

2.

The torque fluctuates due to the rotational

deviation of the reel drive unit. Use the center of the fluctuation as the value.

3.

Place the unit in the EP record mode, and check

that the take-up torque is within the range.

Torque gauge

Place the torque gauge on the supply reel disk, and turn it counterclockwise very slowly (one rotation every 2 to 3 seconds) and check

that the torque is within the set value

170 f: 40gcm.

Figure

Note:

Set the torque gauge securely on the supply reel

disk. If it is not secure, the measurement will be incorrect.

l

Adjustment

If the take-up torque in video search rewind mode

is outside the range, replace the supply reel disk.

30

Note: The torque fluctuates due to the rotational deviation of the supply reel disk. Use the center of the fluctuation at the value.

l-32.

v

.N

I7

Supply reel disk

l

Adjustment

If the take-up torque in the playback mode is

outside the range, replace the take-up reel disk.

Note: Stabilize the cassette torque meter to prevent floating.

27

CHECKING THE FAST FORWARD BACK TENSION

l

Remove the cassette housing control assembly.

l

Checking

CHECKING THE VIDEO SEARCH REWIND

BACK TENSION

Remove the cassette

l

Checking

housing control assembly.

\‘I//

fast forward mode.

Place the torque gauge on the supply reel disk, and turn it clockwise very slowly (one rotation every 2 to 3 seconds) and check that the torque is within

15 f 5gcm.

Figure

l-33.

Supply reel disk

Note :

Set the torque gauge securely on the supply reel

If the torque gauge is not securely set on the

disk.

reel disk, measurement will be incorrect.

CHECKING

l

Remo

THE

REWIND BACK TENSION

ve the cassette housing control assembly.

\‘I//

Push the play button to place

the unit in the playback mode. button to place the unit in the

Place the torque gauge on the take-up reel disk, and turn it counterclockwise very (one rotation every 2 to 3 seconds) and check

that the torque is within the set value

45

5 2Ogcm.

Push the video search rewind

videosearch rewind mode.

Torque gauge

s10wly

Figure

l-35.

\\I//

Note :

Set the torque gauge securely on the take-up reel disk. If it is not secure, the measurement will be

incorrect.

Take-up reel disk

Check

:ing

Place the unit in the

rewind mode.

Take-up reel disk

Place the torque gauge on the

take-up reel disk, and turn it

counterclockwise very slowly (one rotation every 2 to 3 seconds) and check that the torque is within 15 t

Figure

l-34.

5gcm.

l

Note: Set the torque gauge securely on the take-up reel

disk. If it is not secure, the measurement will be

incorrect.

CHECKING THE PINCH ROLLER PRESSURE

Remove the cassette housing control assembly.

l

Capstan shaft

rusn the play button to place

unit in the playback mode.

ension gauge adaptor

the

28

Figure

l-36.

I.

Detach the pinch roller from the capstan shaft.

2.

Set the tension gauge by hooking the tension

gauge adapter onto the pinch roller shaft.

3.

Gradually release the pressure to allow the pinch

roller to touch the capstan shaft. When the pinch roller just touches the capstan shaft, read the indication on the gauge.

4.

Check that the reading of the tension gauge is in

the range of

1000

to

1200 g.

CHECKING AND ADJUSTMENT OF TENSION POLE POSITION

l

Remove the cassette housing control assembly.

l

Setting

\‘I//

VT-341

8X

VT-5118X

2.

At the beginning of the tape

the tension pole’s left side is aligned with the supply impedance roller’s center by sight.

3.

Check that the end of the tape is neither curled

against the flange of the supply impedance

roller nor over it.

4.

During the video search rewind mode with no

cassette tape in place, check that the supply reel disk is free from the tension band.

l

Position adjustment (record mode)

When the tension pole is at the right of the supply

impedance roller’s center:

Untighten the tightening screw, and shift the

tension band adjustment bracket in the direction of the arrow using a tension band and plate adjusting Jig until it is in the set value range (center). Then secure it with the tightening screw.

(Center

(E-180),

check that

Guide roller A

F. E.

head

SUPPlY

impedance.

roller

Check the left side position (by sight).

g-&n arm&YkPes

Place the unit in

the record mode.

roller B

.Guide

Center

I

/-SUPPlY

:

impedance roller

Tension pole

‘ension band adjustment bracket

T

l

Position adjustment (record mode)

I)

Tension band

and plate adjusting jig

Figure

l-38.

When the tension pole is at the left of the supply

impedance roller’s center:

Untighten the tightening screw, and shift the

tension band adjustment bracket in the direction of the arrow using a tension band and plate adjusting

Jig until it is in the set value range (center). Then secure it with the tightening screw.

/enter

Tension and plate adjusting jig setting hole

band’m

l

Checking

1

Video Cassette tape (E-l

b)

Figure

l-37.

I. The guide rollers (A, B) operate to bring the tape

outside the cassette tape and simultaneously the tension pole moves to the left, loading the tape.

At that time (loading completed), check the

position of the tension pole.

80)

500

g

<Center

I

Supply impedance

roller

!

Tension

a

pole

lir

Tension band adjustment bracket

I)

Tension band

and plate

adjusting jig

Figure

l-39.

VT-341 8X

VT-5118X

CHECKING AND ADJUSTMENT OF

RECORD / PLAYBACK BACK TENSION

l

Remove the cassette housing control assembly.

l

Checking

Tension spring

cf*

\

Weight a

VI

\\‘I/

_‘

9

I.

Put a cassette torque meter into the unit.

2.

Push the record button to place the unit

record mode.

3.

Check that the back tension indicated by the

gauge is within the set range 31 to 36

Notes:

1.

Make sure that the video cassette tape is over

the retaining guide.

2.

Make sure that the tape is not slack nor

damaged at either end.

/

REC -

/

.

Cl

‘1

I\’

Push the record button to place the unit

in the record mode.

Figure

l-40.

chassis

i-n

g-cm.

\

the

Tension spring hook plate

Figure

/Tension

Tension spring

hook plate

l-41.

spring

CHECKING THE BRAKE TORQUE

l

Checking the brake torque at the supply side

Torque gauge

‘,ysply

reel

l Adjustment

1.

If the reading of the cassette torque meter is less

than specified, move the tip of the tension spring

hook plate toward the hole A.

2.

If the reading of the cassette torque meter is

more than specified, move the tip of the tension spring hook plate toward the hole Note: Put a thin screw driver it toward you, and turn it for easier shift of the

tension spring hook plate in the direction of A or

B.

(-)

in the shaft hole, lean

B.

l-42.

130 g-cm,

CCW

direction.

idler gear

250

to

and that the

djust the

Mechanism chassis

1 I

Remove the cassette housing control assembly.

2.

Place the mechanism in the stop mode by

unplugging the power cord in the fast forward

or rewind mode.

3.

Slowly rotate the torque gauge in the clockwise

(CW)

direction and counterclockwise direction of the supply brake so that the reel disk and the indicator of the torque gauge rotate at an equal rate. Check that the values are within

the range of CW direction =

CCW

direction

brake torque in the CW direction is at least twice

as high as that in the

m

Figure

=90

to

30

(CCW)

750 gem,

j

KZ::

l Checking the brake torque at the take-up side

wchanism

chassis

-upreel

REPLACEMENT OF MAIN BRAKE

1.

Remove the reel belt and the reel block

Flat Cable).

2.

Remove the cut washer @ off the brake shifter.

3.

Unscrew the four screws Q and then the

up reel retainer.

4.

Remove the reel block assembly @ downward.

5.

Remove the cut washer 0 first and then the reel

pulley.

6.

Unscrew the two screws @ and detach the idler

assembly.

7.

Unhook the back tension lever spring @ and

remove the back tension lever Q. (Undo the hook under the reel chassis.)

8.

Open the shifter latch 8 and remove the brake

shifter assembly

9.

Release the reel disk catchesand @ then remove

the left and right reel disk assemblies 8 and

10.

Finally remove the main brake levers

main brake spring @ .

@I.

FFC

0

and the

(Full

take-

0.

Figure

l-43.

1.

Remove the cassette housing control assembly.

2.

Slowly rotate the torque gauge in the clockwise

(CW)

direction and counterclockwise

direction of the take-up brake so that the reel

disk and the indicator of the torque gauge

rotate at an equal rate. Check that the values are within the range of

750 gem, CW

that the brake torque in the

least twice as high as that in the CW direction.

0

Adjustment of the brake torque at the supply

side and the take-up side

1.

If the supply or take-up brake torque is outside

the range, clean the supply or take-up reel disk break lever felt, then recheck the torque.

2.

If the supply or take-up brake torque is still

outside the range, replace the main brake or the main brake spring.

direction = 90 to

CCW

direction =

CCW

130 g-cm,

direction is at

(CCW)

250

to

and

Figure

l-44.

Note:

When the main brake is replaced, perform the

height checking and adjustment (see page

the brake torque checking (see page

30).

31

25),

and

VT-341 8X W-5118X

REPLACEMENT OF A/C (Audio/Control) HEAD

1.

Remove the cassette housing control assembly.

2.

Place the unit in the unloading mode, and

unplug the power cord.

l

Removal

I.

Loosen the tilt adjusting screw

2.

Remove the azimuth adjusting screw

3.

Remove the A/C head screw

4.

Unsolder the A/C head

head assembly.

Notes:

1.

After replacement, be sure to perform the

adjustment of the tape drive train (see page

Under any circumstances, avoid touching the head. Clean the head, if touched with your

finger, with alcohol.

2.

Take care that the azimuth spring does not fly

off when removing the A/C head screw.

4

n

PWB

0. Q.

0.

soldered to the

A/C

33).

Figure

l-47.

l

Adjustment

[A/C head tilt angle]

l_

Set the mechanism to the loading mode.

2.

Place the A/C head tilt adjusting Jig

3 Slowly turn the tilt adjusting screw Q with a

screw driver until there is no gap between the Jig and the A/C head.

0.

Pay attention to

Figure

l-45.

l

Replacement

1.

Solder the removed A/C head

A/C head assembly.

2.

The A/C head assembly is attached so that the

A/C head arm and

parallel to each other.

A/C

head plate are roughly

PWB

onto a new

Solder

/

LR

PWB

h

A piece of white paper

1

usting

Screw driver

New AK head

Never touch the head

ass’y

Fiaure 146.

32

AK

head arm

f

b)

Figure 1-48.

[A/C head height rough adjustment]

AK

head

adjusting

Weight

Roughly adjust the height of the AK head by turning

the AK head adjusting

hexagon nut with the specialized box drive until the tape is in the position shown

below.Weight

Reverse guide

adjusting jig

of 5009

ism

chassis

HEIGHT ADJUSTMENT OF REVERSE GUIDE

Note: Before the rough adjustment of the tape drive

train, check that the retaining guide height is within the value in Figure

Jigs.

height-\

To readjust the height, remove the cut washer from behind, take out the spring, lift the

reverse guide and add a washer.

(a)

.

-Reverse guide Reverse guide

height

l-50

by using the special

7

(b)

Reverse guide

AK

head

Adjust the nut visually so that

.

the control head is visible to

0.5

mm below the bottom

of the tape.

Figure

l-49.

0.3

Adjust the height using

-

Spring

*

.-Spring

El

@Washer

@Cut

bination

O-5,0.4,0.25 and 0.13.

Mechanism chassis

(iron flat)

washer

2.1-5-O-5

of washers

(4

Figure

l-50.

f

33

VT-341

8X

i/T-5118X

ADJUSTMENT OF TAPE DRIVE TRAIN

1.

Remove the cassette housing control assembly.

2.

Check and adjust the position of the tension

pole. (See page

3.

Check and adjust the video search rewind back

tension. (See page 28.)

4.

Set the tilt angle of the A/C head. (See page

5.

Rough adjustment of tape drive train.

Connect the oscilloscope to the test point for

a)

PB CHROMA

the synchronism of the oscilloscope to EXT. The PB the head switching pulse

Loosen the setscrew at the lower part of the

b)

guide roller, and adjust it with an adjusting screw driver

roller turns smoothly. (Do not overloosen the

setscrew, which causes insecurity of the guide

roller.) (See Figure

Set the alignment tape (monoscope pattern)

d

on the reel disk, and place the unit in the playback mode. (Place a prevent floating of the cassette tape.)

29.)

envelope output

CHROMA

500

signal is to be triggered by

(TP2202).

(JIGDRIVERH-4)

1-51.)

g weight on the cassette tape to

(TP2201).

so that the guide

32.)

Set

.;w;;

Wrinkles at upper flange

(a)

Wrinkles at lower flange

Clockwise

Counterclockwise

Guide roller

Hexagon

Figure

l-51.

Change the envelope waveform from MAX to

d)

MIN, and MIN to MAX by pushing the (-) tracking button, and check a flat response

is obtained on the waveform.

If a flat response cannot be obtained, roughly

e)

adjust the guide rollers on the supply side and take-up side using an adjusting screw driver

until a flat response can be obtained. Turn the screwdriver to prevent the tape from wrinkling at the upper and lower flanges of the fixed guide.

1)

Wrinkles at the upper flange : Turn the

above adjusting screw clockwise, as shown

in Figure

2)

Wrinkles at the lower flange : Turn the

above adjusting screw counterclockwise, as shown in Figure

A/C

head tilt adjusting screw with a

l-53

(a).

l-53 (b).

l-52.

(+)

or

b)

Figure

l-53.

Notes:

Place the tracking control in the center position, and adjust the X-position adjusting nut so that

the PB

easier rough adjustment of the tape drive train. In the rough adjustment, pay particular attention to the outlet side.

Loosen the setscrew o

CHROMA

0

w

R#

Figure 1-54.

envelop becomes maximum for

. .

X-position adjusting nut

Figure

l-55.

34

PB CHROMA

envelope

(TP2201)

Azimuth adjusting screw

Head switching pulse

Figure

6.

Adjustment of A/C head height and azimuth

(TP2202)

l-56.

a) Connect an oscilloscope to the audio output.

(Pin

(7)

of EL connector)

b)

Use the alignment tape and play back its

audio 7

kHz

signal (monoscope pattern for

video signal). Adjust the azimuth adjusting

screw to obtain the maximum audio output on an oscilloscope. (See Figure

c)

Use the alignment tape and play back its

l-57.)

audio 1 kHz signal (colour bar for video signal) and slowly rotate the A/C head height adjusting nut with the special box driver to obtain the maximum audio output.

d)

Perform the adjustment in b) again.

e)

After this adjustment, apply glyptal to the

screws and nuts to fix them.

Figure

l-57.

7.

Adjustment of tape drive train and X-Position.

l-58.

a) Connect the oscilloscope to the test points

(TP2201)

for PB CHROMA envelope output. Set the synchronism of the oscilloscope to EXT. The PB

CHROMA

signal is to be triggered by

the head switching pulse (TP2202).

b)

Play back the tape drive train alignment tape.

c)

Push the

envelope waveform from MAX to

(+)

or

(-)

button to change the

MIN, MIN to MAX. Adjust the guide roller’s height

on the supply and take-up sides with an adjusting screw driver, to obtain an envelop waveform that is as flat as possible.

d)

If the tape is above or below the helical lead,

the PB shown in Figure

e)

Adjust for maximum flatness of the envelope

as

CHROMA

waveform will take the shape

l-59.

the step 5, e) in page

34.

and

Adjustment

When the tape is above the helical lead.

Supply side

Take-up side

~~~tyzqyy~t-yyjjq

,pJ

Supply side guide Take-up side guide roller rotated in roller rotated in clockwise direction (lowers guide roller) to flatten envelope. flatten envelope.

yJ

clockwise direction

(lowers guide roller) to

Figure

l-59.

35

When the tape is below the helical lead.

Supply side

E---l

Supply side guide

roller rotated in counterclockwise direction (raises guide

roller) to make the tape float above the

helical lead. The supply side guide roller is then rotated in the clockwise direction to flatten the envelope.

Take-up side

Kr>

Take-up side guide

roller rotated in counterclockwise direction (raises guide roller) to make the tape float above the

helical lead. The take-up side guide

roller is then rotated in the clockwise direction to flatten the envelope.

VT-341

8X

VT-5118X

f)

Push the

that a flat response is obtained on the

envelope waveform.

g)

Secure the guide roller by tightening the

guide roller setscrew in the unloading mode.

h)

Play back the tape drive train alignment tape

to check that the envelope waveform does

not change.

8.

Adjustment of A/C head X-position.

a) Push the ( +) and

same time to the preset mode.

b)

Rotate the X-position adjusting nut with an

adjusting box driver, and adjust the position for maximum head switching pulse low side envelope.

c)

Adjust the playback switching point.

d)

Check the flatness of the envelope waveform

and sound by playing back a recorded tape.

X-position adjusting

(+)

or (-) tracking button to check

(-)

tracking buttons at the

nut

A/C

head

l

Reassembly

1.

Mount the capstan motor on the mechanism

chassis making sure not to allow the capstan shaft to hit the mechanism chassis, and attach it with the three screws.

2.

Insert the

control

3.

Attach the reel belt.

PWB.

FFC

into the capstan

D.D.

motor

Notes:

1.

After installing the capstan

to rotate the capstan

D.D.

motor, be sure

D.D.

motor and check the

movement.

2.

Check and adjust the servo circuit.

REMOVAL AND REASSEMBLY OF THE LOADING GEAR BLOCK

Notes:

1.

Remove the cassette housing control assembly.

2.

Remove the reel belt.

3.

Remove the reel block.

1-2

mm

Main

chassis

Figure

l-60.

REPLACEMENT OF THE CAPSTAN D.D.

(DIRECT DRIVE) MOTOR

l

Remove the cassette housing control assembly.

l Removal (Follow the order of

numbers.)

Remove the three screws.

ingicated

l

Notes:

1.

2.

Remove the washer

Removal

Use care not to deform the parts hooked to the

slow brake shaft cap, take-up loading gear and supply loading gear as shown in Figure

Figure

l-62.

in removing the loading gear, secure the guide

roller with a rubber band or the like beforehand

for easier reassembly.

Remove the E-ring

Loading relay gear

Figure 1-61.

36

Figure

l-63.

VT-341

8X

VT-5118X

Remove the slow brake spring

1.

Remove the washer

2.

Remove the slow brake lever

3.

Remove the E ring

4.

Rotate the take-up loading gear, take-up

5.

@.

0.

loading arm assembly, supply loading gear and supply loading arm assembly slightly in the loading direction, and take them @ all out.

Remove the E ring

6.

Remove the relay gear drive lever

7.

0

Reassembly

8. @.

Reverse the procedure. Be sure to match the tally marks on the gears.

Screws

Figure

l-65.

Note: When using a magnetic screw driver in removal of three screws, do not allow the magnetic driver to

hit the A/C head or drums.

Figure

l-64.

Notes:

1.

When reassembling, apply specified grease to the following points; all the gear teeth, all the

gear shafts and the cam groove of loading relay gear.

2.

Be careful not to deform the supply/take-up

loading arms.

3.

Be careful to keep clean the slow brake lever felt.

4.

Be also careful to keep the outer surface of the capstan

D.D.

motor free from dust and dirt. (If stained, the MR (Magnet Resistor) element might be damaged.)

5.

Take care not to deform the anti-fall hooks of the slow brake lever, slow brake shaft cap and supply/ take-up loading gears more than required.

REMOVAL AND REASSEMBLY OF LOADING BLOCK

l

Removal

1.

Remove the cassette loading belt

2.

Unscrew the three screws

3.

Pull the loading block upward.

Q.

0.

Reassembly Turn the master cam all the way counterclockwise.

Ma_tch

the tally mark on the cam switch with the

matching mark.

Fit the loading block and the

master cam with each other. Tighten up the

three screws.

Tally mark

Cam switch

Figure

l-66.

4.

Finally connect the leads and apply the cassette loading belt.

Notes:

1.

Be careful not to scratch the gear.

2.

Be careful not to stain the belt. If dirty, clean it

up with the specified cleaning liquid.

REPLACEMENT OF LOADING MOTOR

1.

Set the cassette ejected condition by placing the

unit in the cassette eject mode.

2.

Unplug the power cord.

3.

Remove the loading block in accordance with

the statements and drawings above.

37

c

W-341

8X

W-5118X

I

1

0

Removal

Figure

l-67.

1.

Unsolder the leads 0 from the loading motor.

2.

Unlock the left and right catches Q of the cam

switch off the loading block. Take out the cam switch and loading block

,-Tally

marks

oading

PWB

(See Figure

block

PWB

l-68).

Loading mot

3.

4.

5.

6.

3.0fO.l

+

33

=I

IilL

Note:

When press-fitting the loading

motor pulley, keep the pressure less than 5 kg, and the gap between the motor and pulley

Figure

l-70.

Set the loading block

should be

PWB

and the cam switch in

3.0 2 0.1

Figure

l-71.

position. Resolder the leads to the loading motor.

Finally place the loading block (See page

Attach the loading belt.

mm

mm.

37).

Pull up the cam switch pressing the catches. Remove the cam switch

Catches of cam switch

3.

Take out the loading belt

4.

Pry up the back end of the loading motor with a

screw driver or the like as in Figure

together with the loading btock

Figure

l-68.

0.

l-69

and take

out the motor.

3

Motor label

putthetipof

screwdriver or the

like here. Pry UP the back end of the

loading motor and

take out the motor.

l

Reassembly

1.

Remove the loading motor, and mount a new

a

4

0

Figure

loading motor as in Figure

2.

Place the loading motor so that its label is visible

as

shown

in Figure

7

l-69.

l-70.

Make sure that the

Loading belt

Q

screw hole at the motor shaft, protuberance *on

the

bading

block, and the motor’s back end

marked with the arrow are mated with each

other.

PWB.

Reve

REPLACEMENT OF MASTER CAM

l

Removal

1.

Remove the E ring

2.

Remove the pinch roller lever

3.

Pull out the master cam 0 upward.

P

I

\

0. a.

Pinch roller lever

Pinch

I t

0

Master cam

lever cam follower

(Place the relay shifter

lever to the unloading position.)

w

brake lever cam follower

Figure

l-72.

roller lever

Bottom side of master

ay

shifter

cam

fOllOW

ler

38

VT-341 8X W-5118X

0

Reassembly

1.

Place the relay gear drive lever in the unloading

state.

2.

Place the relay shifter so that it is in contact with the reverse guide spring hole in the mechanism chassis. Release the slow brake lever with a finger to bring it away from the capstan (in the direction of arrow). Then place the master cam so that the D cut-off part of the master cam faces the direction of arrow.

Turn the master cam somewhat clockwise until

3.

the pinch roller lever’s cam follower goes into the master cam’s groove (marked with arrow). Mount the pinch roller lever and then attach the E ring.

4.

Rotate the master cam by hand to make sure all the four levers (relay gear drive lever, pinch roller lever and relay shifter lever) are in the cam grooves in place.

5.

Mount the loading block. (See page

37.)

Notes:

1.

Be careful not to scratch the teeth and grooves

of the master cam.

2.

After installation of the master cam, be sure to

rotate the master cam by hand before installing the loading block.

If the levers are in wrong

position, the master cam and the levers may get damaged when the motor stares. Apply specified grease to the master cam’s

3

grooves and teeth.

Unsolder the leads.

and tighten the

Turn

Figure

l-73.

l

Reassembly

Notes:

1.

Before setting the drum, check that there are no scratches or dust on the edge of the surface and circumference of the disk.

2.

Before setting the drum, check that there are no scratches or dust on the internal surface and

edge of the surface of the upper drum.

3.

On assembling these parts, insert the upper drum onto the disk with care, so that the upper drum is not tilted.

4.

When assembling these parts, do not allow dust

or dirt come between the disk and the upper drum.

5.

Do not use excessive force when driving in the screws.

REPLACEMENT OF UPPER DRUM

Note: The gap between the lower drum and the upper drum is very accurate, in the order of microns, and care should be paid to their replacement. Even a slight amount of foreign material will affect the

accuracy of their reassembly.

l Replacement (Follow the order of the indicated

numbers.)

Notes:

1.

Avoid touching the drum surface

hands.

2.

Pull out the upper drum with care so that it may not be tilted, and replace it with the upper drum replacing jig using care not to damage the disk

circumference.

3.

Do not hit the screws when tightening them.

with’bare

Figure

l-74.

1.

Set the new drum.

Fasten the upper drum in place with the two

2.

screws.

3.

Solder the leads. Note: Soldering should be performed quickly and carefully without touching adjacent patterns.

4.

After replacement, be sure to check the tape drive train adjustment (see page 34.) and the following electric adjustments.

l

Adjustment of the playback switching point.

l

Checking and adjustment of the X-position.

l

Adiustment

of SP and

EP

slow

trackina

oreset.

39

VT-341 VT-51

8X

18X

REPLACEMENT OF D.D. MOTOR

l-

Put the unit in the cassette eject position.

2.

Unplug the power cord.

l

Removal (Reverse the order in reassembly.)

1.

Remove the

2.

Remove the two

a.

3.

Pull out the

4.

Remove the three

5.

Remove the

Notes:

1.

When removing the

stator

assembly, use care not to hit the loading

relay gear.

2.

Secure the

installation positioning holes in the assembly and lower drum assembly match.

3.

Be careful not to damage the upper drum or the

video head.

4.

Be sure that the hall device and the

assembly are not damaged by the assembly or other parts.

5.

After installation, adjust the playback switching

point.

FFC 0.

0.0.

rotor assembly setscrews

0.0.

rotor

ass’y 0.

0.0.

stator setscrews

0.0.

stator assembly

0.0.

rotor assembly or

0.0.

rotor assembly so that the

@.

0.0.

rotor

0.0. stator

0.0.

rotor

0.0.

REPLACING THE

CLEANER)

AHC

(AUTOMATIC HEAD

setscrew

Figure

l-75

setscrew

positioning

rotor

ass’y

D. D. stator

FFC

Figure

l-76

l

Removal

1.

Unhook pat-t 0 with a finger in the direction of

,

ass

Y

arrow.

Hold the rib (marked with an arrow) of the

ass’y Q

pull the

with electrician’s pliers or the like, and

ass’y

upward in the direction of arrow

0.

Note:

To pull out the AHC

l

Reassembly

I.

Push down the

arrow @. Make sure that the

position by the hook of part

ass’y,

hold the AHC lever down.

AHC ass’y

in the direction of

ass’y

is secured in

0.

Notes:

1.

Be careful to keep the

AHC ass’y

out of contact

with the drum.

2.

Be careful to keep the cleaner section of the

free of grease of contaminants.

AHC

ass’y

40

ADJUSTMENT OF THE

VCR ELECTRICAL CIRCUITRY

Notes:

Q

Before the adjustment:

Electrical adjustments discussed here are often required after replacement of electronic mechanical parts such as video heads. Check that the mechanism and all electric components are in good working condition prior to the adjustments, otherwise adjustments can not be completed.

l

Instruments required:

@Audio @ @AC @ @ 0 @Colour bar generator

n

signal generator

Dual-trac

milli-voltmeter

Frequency counter Blank video cassette tape Screwdriver for adjustment

e oscilloscope

@DC

@Alignment tape

@

SERVO CIRCUIT ADJUSTMENT

voltmeter

(VROCPSV)

Extension connector

(QCNW-3778CEZZ: AB - AB)

(QCNW-3780CEZZ:

AL - AL)

Adjustment of head switching point

Measuring instrument

Dual-trace oscilloscope

components

and

Mode Cassette Test point

Control

Specification

1.

Play the alignment

2.

Short circuit test points

the A/V Jack housing (See Note below)

3.

Connect a dual trace oscilloscope to the VIDEO

OUT (pin (Trigger the oscilloscope with the head switching pulse on TP2202.)

4.

Adjust

head switching pulse is 6.5H (lines) ahead of the

vertical sync as shown in Figure

ass’y

R7701

Playback

Alignment tape

VIDEO OUT (pin connector) to CH 1

TP2202

(Located on the Y/C

R7701

adjustment control

6.5 2 0.5

PWB

to set the auto tracking to center.

(3)

of EL connector) and TP2202.

so that the leading edge of the

(Trigger) to

head switching point

H (lines)

tape.(VROCPSV.)

TP8201

or remove the cassette

(VROCPSV)

(3)

of EL

CH2

PWB)

and

TP8202

2-1.

on

CH-1: 1

V/div 50pseddiv

CH-2:2V/div

CH-2

HEAD . SWITCHING PULSE

Notes: To make this adjustment, disable the AUTO TRACKING function. The AUTO TRACKING function is disabled in the following cases. (In the playback mode only.)

@When

removed, press both tracking control buttons of the remote control unit at the same time to set the tracking in center.

Q

When test points

jack

i(

-

the cassette housing control

PWB

are short-circuited.

6.5 2 0.5H

Figure

TP8201

(lines)

2-1,

and

-;

TP8202

50peddiv

V-sync.

ass’y

is

on the A/V

41

VT-341

VT-5118X

n

8X

Test points layout of VCR Main Unit.

I

0 El

KS60

I

EA

08603

1

f

I

El3

0

EK

IceaOZ

0

ICfmO?

OEEl6

0

EJ

I

yoQi

:

IC770

I

Adjustment of PAL System tracking Preset

Measuring instrument

Mode

Monitor TV

Recording and playback on recording tape at SP and LP mode.

SP

E’/_

/ LP

U

EH

J. X6BOl

8

lc&so I

\

,,’

I

ok o

Figure 2-2.

~10~

self-

09904

0

J

to

OEEOB

0

08814

0990

09906

o

Adjustment of

tracking Preset

Measuring instrument

Mode

0

09905

ED

fg

EN

I

ii?,,

~p.s50,

05603

0

lAl

NTSC

System SP / EP slow

Monitor TV

Recording and playback on

recording tape at SP and EP mode.

EG

IC660

I

BIASI+

TP6602 BIASI-

RIL 0

BIAS ADJ

0 uoggo’

10660

0

T6601

02301

0

06602

IC990

06607

06606

00

0 II

0660

yy

I

.

0

K7701

EL

I

self-

Input signal

Test point Adjusting point

Specification

1.

Play back the SP self-recorded tape in the PAL

PAL System Commercial broadcastor video signal.

Monitor screen

Tracking control button (+ ), (-

No noise bar on the monitor TV screen.

)

System slow mode.

2.

Make the test points

circuited in the Jack

3.

Be sure that the PB mode display

TP8201

PWB.

and

TP8202 short-

(b)

disappears

on the screen.

4.

Remove the short-circuit.

5.

Adjust the tracking control using the TRACKING

buttons on the remote controller so that there is no noise on the screen.

6.

Play back the LP self-recorded tape in the PAL

System Slow mode.

7.

Make the test points

circuited in the Jack

8.

Be sure that the PB mode display

TP8201

PWB.

and

TP8202 short-

(b)

disappears

on the screen.

9.

Remove the short-circuit.

lO.Adjust the tracking control using the TRACKING

buttons on the remote controller so that there is no noise on the screen.

NTSC

Input signal

Test point

Adjusting point

Specification

1.

Play back the SP self-recorded tape in the

system

Commercial broadcast or video signal.

Monitor screen

Tracking control buttons

No noise bar on the monitor TV screen.

(+), (-)

System slow mode.

2.

Make the test points

circuited in the Jack

3.

Be sure that the PB mode display

TP8201

PWB.

and

TP8202 short-

(b)

disappears

on the screen.

4.

Remove the short-circuit.

5.

Adjust the tracking control using the TRACKING

buttons on the remote controller so that there is

no noise on the screen.

6.

Play back the EP self-recorded tape in the

NTSC

System Slow mode.

7.

Make the test points

circuited in the Jack

8.

Be sure that the PB mode display

TP8201

PWB.

and

TP8202

(b)

short-

disappears

on the screen.

9.

Remove the short-circuit.

lo-Adjust

the tracking control using the TRACKING buttons on the remote controller so that there is no noise on the screen.

NTSC

42

Adjustment of PAL System still

picture

vertical sync

Measuring instrument

Mode

Input signal Test point Adjusting point

Specification

1.

Flay back the self-recorded tape in

System still mode.

2.

Using the TRACKING buttons on the remote

controller, make adjustment so that jitter becomes minimum.

3.

Now press the STOP button to stop the tape.

Adjustment of

Monitor TV Still picture playback

PAL self-recording tape Monitor screen Tracking control buttons ( + ),

t-1

1

No noise jitter

th’e

NTSC

System still picture

vertical sync

PAL

VT-341

I

VT-51

I

4

Y/C CIRCUIT ADJUSTMENT

8X

18X

Adjustment of video E-E level

Osci

Nleasuri ng

instrument Mode

I

1

Input signal

Test point

Control

I

I-

1

Specification

1.

Connect an oscilloscope to the VIDEO OUT

(pin

(3)

of EL connector).

2.

Feed a

and put the unit in AV input mode.

3.

Adjust

2.OVp-p

(See Note below)

colour

R2202

as shown in Figure

I loscope

E-E or Record

I

1

PAL colour bar (1

VIDEO OUT (pin

(3)

of EL connector)

R2202

I

1 2.0 i 0.2 Vp-p

bar signal to the VIDEO IN jack

so that the signal amplitude is

E-E level control

.OVp-p)

2-3.

I

Measuring instrument

Mode

Input signal Test point Adjusting point

Specification

1.

Play back the self-recorded tape in the

System still mode.

2.

Using the TRACKING buttons on the remote

controller, make adjustment so that jitter becomes minimum.

3.

Now press the STOP button to stop the tape.

Monitor TV

I

Still picture playback

I

I NTSC

self-recording tape

Monitor screen

I

Tracking control buttons ( + ),

(-1

1

No noise jitter

NTSC

I

Note:

After this adjustment, check the deviation of FM

luminance signal.

adjustment.)

Adjustment of

Measuring instrument

Mode

I

Input

I

I I

signai

Test point Control Specification

7%

Figure 2-3.

(Frequency and Deviation

VCO

DC Voltmeter

E-E or Record

I

1

PAL colour bar (1 .O Vp-p)

I TPSSOl(Signal), TP5502(GND)

FL5501 VCO

I

2.25 +,

O.lV

I

43

1.

Feed a

and put the unit in AV input mode.

2.

Connect the DC voltmeter to test points

TPSSOl(Sig.)

3.

Adjust

2.25 + O.lV.

colour

bar signal to the VIDEO IN jack

and

TP5502 (GND).

FL5501

so that the DC voltmeter reads

WTest

points

layout of Y/C Unit.

r

0

05512

Adjustment of white clip

Measuring instrument

Mode Input signal

Test point

Control

Specification

Osci

I loscope

E-E or Record PAL colour bar (1

TP2205(Signal), R2203

white clip control

190 +

5% (See note below)

---___-

02223

0

.OVp-p)

TP2206(G

N

D)

PB-Y

R2201

_

LEVEL

IC220 I,^\

Figure

-

.- _-_---

GJ yyPT

TP2205 lP2206 C&D

2-4.

A2203

CLIP

----

R2204

DEVIATION

FL5501

cl

__.-

El

TP2201

PB CHROMA

lP2202

HEAD SWITCHING PULSE

lP2203 GND TP2204

REC SIGNAL

Note:

From sync tip to white peak, the level is The white clip level is (There is no dark clip adjustment.)

.

. .

.

.:.:

$2

90%

above the white level.

I

SYNCTIP

I

l-

100%.

1.

Connect the oscilloscope to test points

TP2205(Sig.)

2.

Feed the

and put the unit in AV input mode.

3.

Adjust

signal is clipped at 190% as shown in Figure

and

TP2206(GND).

colour

bar signal to the VIDEO IN jack

R2203

so that the overshoot of the video

2-5.

I

100% WHITE

-.................................w

WHITE CLIP LEVEL

Figure 2-5.

44

Adjustment of FM carrier frequency and deviation

Measuring

instrument Mode

Input signal

Test point

Control

Specifications

1.

Be sure that R2202 (E-E LEVEL) has been

correctly adjusted.

2.

Connect an oscilloscope to the VIDEO OUT (pin

(3)

of EL connector).

3.

Connect a frequency counter to test points

TP2204.

4.

Put the unit in AV input mode. Do not feed any

signal to the VIDEO IN jack. (Disconnect any cable from video input terminal.)

5.

Under this condition, adjust

frequency counter reads

6.

Feed the PAL standard

VIDEO IN jack and adjust frequency counter reads

7.

Repeat step 5

8.

Under this condition record the

on tape, rewind and playback.

9.

Make sure that the amplitude of the playback

colour

bar signal is

Figure the PLAYBACK LEVEL adjustment.

2-6.

Frequency counter

Oscilloscope Record/Playback PAL colour bar (1

TP2204

VIDEO OUT (pin

(3)

of EL connector)

R2205

FM carrier control

R2204

Deviation control

3.8 ,+ 0.05MHz

2.0 +,

O.lVp-p

3.8MHz.

colour

4.3MHz.

thru

7 a few times.

2.0 kO.1

If it is out of specified value, check

(R2201)

.OVp-p)

R2205

so that the

bar signal to the

R2204

so that the

EIA colour

Vp-p as shown in

and retry this

bar

Adiustment

Measuring instrument

Mode Cassette Test point

Control Specifications

1.

Connect an oscilloscope to the VIDEO OUT (pin

(3) of EL connector).

2.

Play the

tape and adjust

amplitude is

of playback level

Osci

I

loscope

Playback Alignment tape VIDEO OUT

(pin

(3)

of EL connector)

R2201

playback level control

2.0 i 0.2

colour

bar portion of the alignment

Z.OVp-p

vp-p

R2201

as shown in Figure

Figure 2-7.

(VROCPSV)

so that the signal

2-7.

Figure

. . . . . . . . .

t

2.0

vp-p

1

lr

. . . . . .

2-6.

45

VT-341

8X

VT-51 18X

n

AUDIO CIRCUIT

Checking of audio play-back level

Measuring instrument

Mode

I

Input signal

Test point

I

Specification

1.

Playback the Alignment tape.

level adjusting signal)

2.

Connect an AC

OUT (pin

3.

Make sure that the output level is - 9 +

AC milli-voltmeter

Playback

I

Alignment

(1

kHz level adjusting signal.)

AUDIO OUT

(pin

(7)

of EL connector)

1 -

9 +

2dBs (0.6-l .OVp-p)

milli-voltmeter

(7)

of EL connector).

tape.(VROCPSV)

(VROCPSV 1 kHz

to the AUDIO

Checking of audio record level

AC

Measuring instrument

Mode

I

Input signal

I

Test point

milli-voltmeter

Osci

I

loscope

I

Record/Playback

1 kHz, -8dBs (0.87Vp-p)

I

AUDIO OUT (pin

(7)

of EL connector)

or

2dBs.

1.

Connect an AC milli-voltmeter to test points

TP6601(

(Use

2.

Set the unit in recording mode.

3.

Adjust

I

2.6mVrms.

+ ) and

TP6602

R6634

TP6602( -).

for ground lead.)

so that the signal amplitude is

Checking of erase voltage and oscillation

freauencv

I

Control

I

Specification

I

1.

Put the unit in record mode.

2.

Connect an oscilloscope across the full erase

head.

3.

Make sure the erase voltage across the full

I

erase head is frequency is 70 +

T660

1

I

70 f SkHz, 4OVp-p

I

approx. 4OVp-p

5kHz.

or greater

or more and

I

1

Specification1 -8 f

1.

Connect an AC

OUT (pin

2.

Feed the audio signal shown in

AUDIO IN jack.

3.

Make the self-recording and playback of the

signal.

4.

Make sure that the AUDIO OUT level is as

specified. If it is out of specified value, verify

the bias current (ADJUSTMENT OF AUDIO BIAS

CURRENT below).

(7)

of EL connector).

2dBs(0.7-l.lVp-p)

milli-voltmeter

to the AUDIO

tableto

Adjustment of audio bias current

Measuring instrument

I

Mode

I

Input signal Test point Control Specification

AC

milli-voltmeter

Oscilloscope

I

Record

I

Not required

TP660 1 ( + ) - TP6602( - )

R6634

2.6 + 0.1 mVrms (7.6 + 0.3mVp-p)

or

the

.

I

Figure 2-8.

I

1

MECHANISM OPERATION FLOWCHART

l This flowchart describes the outline of the mechanism’s operation, but does not give its details. l Function of cam switch bit reading.

The on/off of cam switch is cam position switch

CASW ULSW CD

‘ON’

Mechanism position SW (1) input

1

Mechanism

1

Mechanism position

Mechanism position SW

Mechanism position SW (1)

h

positionSW(2)

SW(j)

(4)

input

input 1 H 1 L 1 H 1 H 1 L I H I H

input I H I H

T

f 47K + 47K 4 47K $ 47K

L

H H H

(l-4)

input signals in conditions as shown in below.

SW

‘ON’ ‘ON’

H H H H

1 T

PB

SW

FLSW PE

I

L I L I H I

SW RV SW

‘ON’

‘ON‘

L L

T

i)

Mechanism position SW

0

Mechanism position SW (2)

0

Mechanism position SW (3)

Mechanism position SW (4)

‘ON’

ATSV

1

L

H

I

c

ALLSW

‘OFF’

H

(1)

I

input input input Input

CASSETTE INSERTION -+ STOP

I

1

Loading motor starts in normal

Cassette inserting

direction and master cam clockwise.

Does cassette control clutch come off within 2.5 sec. after cassette switch has turned off?

L

Are start/end sensors at low level before cassette insertion?

\

I

1

Insert cassette.

t

Turn off cassette switch.

J

I

t

tYE5

+YES

Drum motor starts.

t

Pinch roller comes into contact.

i

Cam switch is at PB position.

I

I I

1

,

I

ND

(Cassette is judged caught halfway.)

1

NO

(Cassette LED or some judged defective.)

I

1

Cassette is ejected and loading motor stops.

I

Cassette switch turns on.

I

Loading motor turns in reverse direction and master cam counterclockwise.

End

t

part is

n

I

0

I

J

z

1

I

n

1

I

b

1

I

A

Mechrnirm

position

sw(2)

/I

Mechanam

position SW

Mechanism position

CAM SW

!

(3)

i

SW(4) i i

CASW

.

: :

: i

: :

. . . i ,

: : : : : : : ; : : :i

. : : . . : :

. .

UL SW

//

i

; :

-j

. .

: :

:

;

:

. .

: : :

. , : :

:

. Shift zone

: :

:.

CD SW

: . :

i

Pa

: : : :

* i

: : : :

SW

: :

;

: .

: * i

;

i

.

. .

PV

SW

Is drum FG pulse outputted?

IYES

I

End

.I0

Unloading

I

STOP -,

REVPLAY

PLAY + STILL

PLAY + VSR VSR --, PLAY

Press

REW

I

key.

I

Loading motor turns in reverse direction and master

Picture appears.

r

Is take-up reel sensor signal outputted?

Set capstan motor to search speed.

t

PLAY

--, VSF

Press FF key.

t

End

NO

Slow brake pressing

Slow brake comes into

Loading motor stops

Capstan motor stops.

+

End

REVPLAY -+

Press STOP key.

I

Stop capstan motor.

STOP

Pinch roller

releasing

Idler swinging

I

1]Release

1

Camswitchis;tPUposition.

, 11

I

Turn capstan motor in

reverse direction.

I

{

I

1 G$MJchis;,VSR

1

11Stop

19zt;;prtan m;r

1

Is take-up reel sensor signal

outputted?

I

Stop

pych

l;dTg

J

loadi;g

motor.

to search

roller.

1

I

Unloading

I

Press

I

It

I

,

1

Cam switch

Stop loading motor.

I

STOP +

FF/REW

t

iI;:::position. ]

End

FF/REW

key.

STOP *CASSETTE EJECT

1

Cassette control clutch is engaged by pinch roller lever.

I

Tape unloading

Capstan motor turns in reverse direction

1

I

Cam switch is at UL Stop position.

t

1

Cassette ejection

I

t

Cassette is ejected.

CYEJ

switch is on.

Stop loading motor.

Stop capstan motor.

1

I

4

1

J

I

Brake latching

Turn loading motor in normal direction.

I

Stop drum motor.

t

Energize brake solenoid.

3

Cam switch is at BS position.

+

Cam switch is at UC stop position.

1

I

Brake

function

FF/REW +

STOP

r

Press STOP key.

t

Stop capstan motor.

Release brake solenoid and brake reel disk.

.

t

End

Tape slack

detectiog

I

L

Release brake solenoid and brake reel disk.

Loading motor turns in reverse direction and master cam

,counter

/

Is take-up reel pu-Ire outputted?

Stop capstan motor in about 5 sec.

clock wise.

Turn capstan motor in reverse direction.

:

1. FF/REW

I

reel disk FF gear in

Is

motor turning?

FAILURE(N0 TAPE WINDING)

Remove cassette controller, turnI:ower

capsten DD

1

MECHANISM TROUBLESHOOTING

I

ey.

I

YES

I

+

Check for broken solenoid lead (turn power off, disconnect check with tester).

FFC

and

-

while attracted, or

(No

broken lead)

t

k 1

Are

Vcc 5V

Vco 12V

applied ?

and

Replacesolenoid.

]

Disconnect and reconnect

FFC.

2.

REVPLAY FAILURE (MODE RELEASE)

I

Remove cassette

1

T

Is brake shifter at PLAY (MC) position?

YES

I

Is

brake shifter at

NO

-

Replace relay shifter.

I

Is take-up reel disk NO

pulse outputted

7

H

Is

capsten DD

motor turning ?

Are

Vcc 5V

Vco 12V

applied ?

and

NO

H

Disconnect and reconnect main

FFC.

I--

Tape travel is presumably overloaded due to damage on tape. Damaged tape is to be out of use.

Replace capstan

DD

motor.

sensor.

I

1

YES

3.

WINDING FAILURE AT

VSR

4.

UNUSUAL SOUND

IN EACH MODE

Remove cassette controller, turn power on and press PLAY key.

‘I

Is take-up normal

during playback 7

‘T

Press

VSR

take-up reel disk by hand.)

Y

Is brake shifter at

VSR

position

7

YES

1 CheckmainPWR. 1

NO

-E

-

key. (Turn

NO_ Replace brake

shifter.

I

Insert cassette and press play and STOP keys repeatedly.

Y

Is rattling sound heard during loading/ unloading

Is reel disk height as

specified (using jig)

Is unusual sound heard at

FF 7

Is unusual sound heard at

REW

I

?

YES

Turn power off and remove cassette controller.

I

Power ON

FF

key IN

NO Press REW key and turn

take-up reel disk by hand.

IH ‘I

7

NO

YES

I

Replace L block

t

assembly. (L block

=

loading block)

,

Turn take-up reel disk slowly with finger. Are

*

take-up reel stopper and

PB

gear rubbing each

other ?

YES

1

Is unusual sound heard with capstan DD motor running

Undo reel belt, turn take-up disk by hand and press FF key.

1

NO

sub-

NO

’

YES

f$ij+-j

-

J

>Fi

If there is no unusual sound heard again in each mode, go back to the start of routine to recheck.

I

L

and down. Is there

-

NO

Replace supply reel disk.

I

VCR POWER

I

TROUBLESHOOTlNG

The VCR

isdead.

KEY-IN

1

FLOW CHART NO. l-l

I

TROUBLESHOOTlNG

Key-h Input is not received.

I

FLOW CHART NO. 1-2

Unplug the AC power cord. it a few minutes later.

I

IS the fuse

mother

I

Are the

normal in the VCR

Are the

properly connected with

I

Is there oscillation at pins (31) and

(32)

I

F701 alright

PWB?

1

YES

UR12V

and

Is the AT 5V line normal ?

ATSV

and

1

YES

of

ICBBOl fIX2522CE)

1

YES

in the TV

UR7V

PWB?

GND

lines

ICBBOl

?

Replug

t

Does pin from * Ii ” to ” L - level when the AC cord is plugged in or ALL CLEAR button is pressed and released?

P,y; “;‘c (!)

the power button is pressed

(20)

of

IC8801

change

i

YES

1

of

ICB~Ol

to

IS

the PC 9V line normal

IS

the PC 5V line normal ?

than

“Ii

level w

1

YES

-NO

1

YES

1

YES

e

en

R

?

7

Is the key switch in good contact 7

I

NO

?

I

NO

L

NO

~

+

t

.

++I

t

I

t

1

Replace the fuse

Check the AT 5V line,

(NJM2930LOS)

Check poor soldering.

Replace

ICBBOl

Check pin

(PST529DZ).

Check power key input to and serial dataslclocks between

IClOOl

(20)

and

in

(6)

of connector EP an

Check Q9903.

and

and /or

of

ICBBOl.

IC9901

R9903.

ICBBOl

FL880 1.

or

ICBBOZ

IClOOl

IC752

I

/;;?r;

short-circuit in the key

L

I

Are signals received at pin

ICBBOI

and pin

the key is activated

Check

I’ne

of serial

1

:eady(L).

+

YES

(4)

of

1

YES

ICBBOl IClOOl

datas

serial clock and

IClOOl

7

and signal

’1

(71)

I

Does the infrared remote control function ?

Is 5V applied at pin remote control receiver ?

I

away from

Is there short-circuit in the key input or

(IX2522CE)

Check line of serial ready

(L)

f

j

YES

the set

? YES

ICl 00 1

or

IC880 1

?

1

YES

IClOOl ICBBOl

data,.

.

serial clock and

(2)

of the

and signal

No

NO

1

ND

of

when

INFRARED R/C

No operation is possible from the infrared remote control.

lLwl

I

kh,eck,key

TROUBLESHOOTiNG

NO

Check the switch contact.

I

Check

4

I

lines to input

+

I

control as required.

I

F

IC8801 (IXZSZZCE), IClOOl (IX2443CE)

soldering.

Check pin

receiven.

Reposition the set not to be exposed to strong light.

and switches for poor

I

Replace the infrared remote

Check the 5V and

(5)

of

IClOOl

Check key input terminals.

ICBBOl

or

FLOW CHART NO.

GND

lines.

and /or

I

*

1-3

1

/

I

,

Check wire harness to mechanism.

I

CASSETTE CONTROL

A cassette tape is not taken in.

I

r

Is

the cassette housing in shape?

I

Are the cam switch and cassette

slider properly positioned ?

I

[

cassette tape is inserted ?

Does

pin 5)

go to cassette tape is inserted ?

I

Doespin(2)

when the cassette tape is inserted ?

I

t

i

YES

1

of

lC8803 (EA6209)

l-i

level when the

$

YES

of

IC8803

I

YES

go to 1lV

TROUBLESHOOTJNG

I

J

NO

I

No

)

Check the cassette switch and all .

No

J

Check the cassette housing.

I

Reposition the cam switch.

the way up to pin

~

Check

IC8801

to pin

(5)

of

I

Check

FLOW CHART NO.

(70)

of

IC8801.

and all the way up

lC8803.

l-4

Does the capstan motor start

J

I

J

I

when the EJECT button is pressed

Does the take-up reel disk turn

when the capstan motor is

running

?

Is

reel

pluse

socket when theta e-up reel disk is turning ?

Is pulse at pin the take-up reel disk is turning

zh;nH;e$e;,;;Rin&t))eof lC8803 No

inputted

?

LOADING MOTOR AND EJECT

Acassette tape fails to eject.

t

7

YES

------IN0

YES

at pin

13)

of

EA

i

YES

(69)

of

IC8801

when

7

1

YES

NO

ND

TROUBLESHOOTJNG

I I

5

Check the reel disk and reel drive

-[b]

Check between pin

t

socket and all the way up to

IC8801,

Check between pin

b

and all the way up to pin

~ IC8801.

FLOW CHART NO.

See FLOW CHART NO. l-7.

Check the reel sensor.

(13)

of

EA

and

Q8809.

(6)

of

lC8803

(11)

l-5

I

of

I

A cassette tape is taken in, but ejected at once.

f

Do start/end sensors voltage at

Fin (9)

I(8) of

If8801

J-i

. to * L - level

when the cassette tape is loaded ?

Does cassette switch voltage at pin

(70)

of

IC8801 than

to OV to

I

2.5V

cassette tape is loaded

Replace

change from

respectrvely

+YES

e from

leve

9

when the

iYES

I

IC8801.

0.8V

7

Is

llVatpin(lO)

Is the correct voltage at the loading motor terminal ?

.

I

ND

1

I

Check the start / end sensors and

)

Check the cassette switch and all the way up to

IC8801.

Does the loading motor run?

Replace the cassette cam, gear, etc.

of

1

YES

1

YES

lC8803?

NO

_rCheck

F

)-

lC8803

and

‘L’

(5)

of it.

Check between

the way up to the loading motor.

Replace the loading motor.

level of pin

IC8803’and

all

VT-341 8X VT-51

18X

is z

0 Y

Y .c

U

J

T

2 c

4

54

TAKE-UP REEL PULSE GENERATOR TROUBLESHOOTING

No reel sensor pulse appears.

I

FLOW CHART NO.

l-8

DRUM MOTOR TROUBLESHOOTING

The drum motor fails to run.

I

FLOW CHART NO.

l-10

DFG w

D-PG -yr--~“t~~~;p

L

*

NO

t

.

Check

IC7701.

Check between the MC socket and

IC7701

socket and \C880

and between the MC

1.

Check the

UR12V

I

line.

Is there the reel sensor

-

pulse at pin (13) of the connector EA ?

NO

Is there the reel sensor pulse at pin (3) of the connector MF ?

NO

Replace the reel sensor (located in the reel sensor

PWB, F2977GE).

-,YES -i:rzpCh..,l,i.yi;;l[

YES

_

Check the harness

MF.

EA-

Is ” H’ pulseatof

IC7701(8Al5218F) 7

Is - H l voltage at pin socket

7

Is UR12V atpin(3)of MEsocket? No

Replace the drum motor.

pin(l

(6)

of ME

YES

The drum motor runs only for a few seconds.

I

tag

,

HEAD SWITCHING PULSE

No head switching pulse.

I

““’

Is

rotating ?

L

t

Are the drum PG and drum FG signal inputted to pins

IC8801, respectively ?

TROUBLESHOOTlNG

the&-NO

YES

(48)

and

(47)

NO

of

YES

FLOW CHART NO.

I

~

See FLOW CHART NO. l-

,

~

pulse.

l-9

10.

,

Is drum PG signal at pin ME socket 7

Is drum PC signal at pin

IC8801?

IS H.

SW.

pulse at pin

Iceeot?

1

YES

(22)

(1)

(48)

of

NO

Check between the ME socket

NO

b

Check the drum motor.

,

t

and pin

(48)

Check

of

IC8801.

4

DRUM SERVO TROUBLESHOOTING

FLOW CHART NO.

l-11

NO

Check pin (4) of the harness ME and the drum motor.

11Drum servo

In PB mode

““;‘

not function.

3

(32)

of

of ICIi3

IC8801

volta

(6)

oft

1

01

YES

1

durm FG

(47)

?

YES

1

e applied“hNO

e harness

YES

Is there 8MHz oscillation at ins and

Is there the

+

f;ggd,;t

,

Is there the head switching pulse at pin

(22)

Is there the drum control to pin ME?

Check and replace the drum motor.

L

of

(31)

?

NO

.

*

1

NO

1

I

+

_

-

c

Check

X8801, C8832

and

C8833.

See FLOW CHART NO. l-l

Does the drum error

amplifier circuit of

(pins

(11,

(2)

operate normally ?

L

and

NO

(3))

1~7701

in

REC

mode

Is there the reference

YES

signal (V-sync. ) at pin

(64)

of

IC8801

?

NO

2.

Check the composite sync. signal at pin (1) of connector El from Y/C

clrcult.

NO

I

Replace IC880

Check

IC7701.

1.

I

k-

Does PB

t

CTL SIPnal

appear at pin 62) of

ICB801 7

+NO

I’ll

YES

CAPSTAN SERVO TROUBLESHOOTING

Fr

Capstan servo does not function.

I

$

YES

I

OW CHART NO.

l-12

Is the harness EO-MR

+NO

normal ?

m/j\

pzG+Kzj

I t YES

$

YES

NO

-

Replace the harness MR.

EO-

Replace

J

IC8801.

Check the composite sync. slgnal line and pin

(1) of connector El from

Y/C

circuit.

Check

I

“@I’.

I

VCR RECORDING MODE

(LUMlNANCE)TROUBLESHOOTlNG

No record.

FLOW CHART NO.

l-13

VCR RECORDING MODE (CHROMA) TROUBLESHOOTING

Record Is In black and white ( E-E color mode

1.

FLOW CHART NO.

I

l-14

Is there a signal at pin (32)

Is there a signal at pin (2)

of connector CE

I

Is there a signal at pin

(14)

of

Is pin level

1

Check cylinder.

I

(TP2204)?

+

YES

IC3301 (TEA5705)?

(28)

of

IC3301 9V

1

+

YES

1

YES

IYES

,

t

Is there a signal at pin

(53)

of

IC2201?

I

1

YES

NO

*

I L

Are there

YJC

of

IC2201

of

IC2201 ?

(3)

DATA and

respectively?

(25)

+

YES

of connector

clock signals at pins (9) and

(10)

Is there SV at pin

(52)

Check pin CC and signal line.

I

and .

NO

-

No

J

Check data and clock signals from

1

+

Check the PC 5V line.

L

IC8801.

8

+~

Check

42213

Is there a signal at pin

(2)

of connector CE 7

I I

1

YES

t ,

Is there a signal at pin

(25)

and

(27)

of

1

YES

IC3301

(TEA5705) 7

1

No

J

NO

No

I

l

I

Check the BIAS line.

I

CTL 9V

I

No

NO

I

NORMAL

I I

Check the signal at pin

(7)

of

IC2201

(Frequency,

(PAUMESECAM)

Frequency, 3.58 MHz.

’ (NTSC)).

?

4.43 MHZ.

*

peripheral circuit.

)

Check the

Check the CHROMA ROTARY line.

L

ABNORMAL

I-I I

t

Check

X5501,2, QSSOS,

10

and peripheral circuit.

and

CE-XB

harness.

Replace

I

IC2201.

I

Are there ri

(17)

of

I

Is there a

(28)

of

I

lC3381?

1

t

signal

IC220

1

VCR PLAYBACK MODE (LUMINANCE)

Are there clock signals at pins (9) and

(10)

of

I

nats

at pin

NQ

IsthereSVatpin(l6)of

+ IC3301

YES

Check

(PAVf&SECAM), and

I

Check the harness from

iXBJ

NO

I

Is

the pin

‘L”

level ?

YES

1 ?

YES

I

at pin

I I

No Playback.

Y/C

DATA and

IC2201

respectively?

?

1

YES

Head

cleanning.

eripheral

YES

toICEJ.

1

YES

(12)

of

1

YES

TROUBLESHOOTlNG

NO

No

NO

H

circuit of

IC2201

42201

42205~Q2iO7 (NTSC).

I

NO

I

Check data and clock

*

signals from

t

Check the PC 5V line.

GOOD

Replace

Q2202-

42204

I

t

Check FV signal line.

I

FLOW CHART NO. 1-15

IC8801.

IC330 1.

J

VCR PLAYBACK MODE

I

(CHROMA) TROUflLESHOOTlNG

Playback is in black and white.

FLOW CHART NO. 1-16

I

Are there

v/C

of

(51)

toiCE

IC2201

of

DATA and

IC2201

respectively?

1

YES

and

J.

clock signals at pins (9) and

(10)

NO

L

Check all the way up to

*

pin the harness from

[XBJ

L

Check and adjust VCO

* (FLS501).

I

of

I~

IC2201 1

f

I

signal

IC2201 7

YES

at pin

Is there a signal at pin

(51)

I

Is there a

(20)

No

1

I

YES

Is there a

(16)

of

IC2201

signal

?

at pin

NO

Check DL550 1 and Q55

+

(PAL),

DL5502

Q5514 (NTSC).

12

and Q5513,

YES

NO

Is there

chroma

?

(11)

1,

YES

?

,4.43

IC5501.

rotary

of

MHz.

NO

1

-

I

signal at pin

IC2201

Check the signal at pin

(7)

of

IC2201 (Frequent (PA”MESF!CAM,

Replace

’

4

Check the

ROTARY line.

ABNORMAL

X5501,2, QSSOS, 10

peripheral circuit.

1

CHRQMA

and

Is there a chroma signal at pin (5) of CC connector

I

Check Q230 1 and harness from f EL J to

IADJ.

7

1

YES

NO

I

1

Is

t

there a signal at pin

(26)

of

IC2201?

YES

of

,

IC2201

?

1

YES

-

r

Is there a signal at pin

(28)

VCR E - E MODE

NO

J

NO

TROUBLESHOOTiNG

NO E-E signal.

Check the harness from f AD J to f EL J and input signal line.

I

t

Is there 5V at pins

and

(52)

L

of

lC220

&YES

1 ?

(25)

NO

FLOW CHART NO. 1-17

VCR SOUND

I

< EE

Sound is not heard >

I

EE

I

Check the ‘L” level at

pin(ll)oflC6601

in

TROUBLESHOOTTNG

No Sound

< EE

Sound is heard

But audio

.,

Is there Bias Oscillator signal at pin pin Oscillator) ?

Check the line between pin

of

IC6601

Head.

(5)

of

(6)

and

T6601

(Bias

YES

REC

Signal

(3)

and Audio

REC

I

is not

Is there an Audio Signal at pin

IC6601

FLOW CHART NO.

< PB

Sound is not heard

(22)

?

of

l-18

>

NO

clock signals at pins and

(10)

of

IC2201

(

Replace

IC2201 )

(9)

signals from

IC8801.

Replace

IC6601.

)J

-1

IQ6602.

I

Signal at pin

1 f ELJ

connector?

I I

Check the

TV mother

I

IC351 (IX0241CE)

PWB.

Check pin (19) of

IC6601

and peripheral

parts.

I

YES

(7)

YES

I

of

-

Check Q6602,Q6601 and peripheral parts.

L

Check the Audio mute circuit;

and

lC352

(TDA7233) on the

Check the

PB

mode.

I

“H’

46606

level at

I

and Q6607.

TROUBLESHOOTING OF TV SECTION

I--------,

I I I

I I

I I I I I. ___----

1

.I

ii

E

b

z

I

VT-341 8X VT-51 18X

61

Circuit to be checked:

1.

TUNER

2.

PIF

3. Automatic gain

control

4. 9V power source

NO PICTURE, NO SOUND

I

t

Does the noise level increase at max

Contrast, Brightness, and Sound Control ?

FLOW CHART

NO.Z-3

FLOW CHART NO.

NO

I

VERTKAL

SCAN

1

CF1601(503kHz)

l-4

Check the tuner bias.

t

I

Normal

I

I I

1

t

Abnormal

t

Is there a signal at pin (7) of

IC35

1

F:4’

Does the 9V ( + 6) appear at pin (9) of

Is there a signal at

f&E Of

t

Check

lC301

and adjacent parts.

0

I

IC1601 pin

Normal

IC501

(lX0640CE)

check

I

parts.

L--------------------~

(29)

bias check.

I

c

I

bias

r--------------------,

I

L---__---------______J

r--------------------~ I

I

L---------1--------_-~

;

I

IC1801

RSOI,

0501,

c501 c503

I

:

FLOW CHART NO.

I

NO SOUND

I

2-S

Circuits to be checked:

a

IC1801 and its

l

R. G. 8.

AdjacentCircuit

Output Circuit

,

NO SPECIFIC COLOUR (PAL)

Specific colours are not produced in

colour broadcast

I(

1

(20)

.

chroma

of

ICl801

and at pin

Is

there a

at pin

(iX0969CEN 1) (8) of connector Y2 or

pin (3) of AD?

signal

receptron.

Check the VCR: TROUBLE SHOOTING

No

-

‘RECORD IS IN

BLACK (EE colour

I

FLOW CHART NO. 1-8

AND WHITE

mode)

i

Check

j I~--~_~~~___~~_-______I

IC35l,lC352

adjacent parts

and

r----------

!

I

Check speaker.

I I

L~~~~~~~~~~~~~~~~_~~__(

NO PLAYBACK PICTURE

NO PLAYBACK SOUND

i Xl802

(PAL

I I

FLOW CHART NO.

I

FLOW CHART NO. Z-7

2-S

L------------------A

1

Check Q851 and its

i

adjacent circuits.

..---_---__--___-__a

4.43MH;) i

The picture colour is

r-----------------mj

;

! CheckQ852andits !

I

i

adjacent circuits

1

,--------‘--------, I

Readjust the white

1

balance.

..__---_---__--____a

The picture

I

colour

1 I

is

I

Circuits to be checked:

l IC1801 and its Adjacent

Circuit

e R. G. IT.

Output Circuit

NO SPECIFIC COLOUR (SECAM)

J

IS there a chroma signal at pin (20) of IC1801

(IX0969CEN 1)

YES

No

-

and at

FLOW CHART NO. 1-9

Specific colours are not produced in

colour broadcast receptron.

No

YES

Circuits to be checked:

l

ICI801

and its Adjacent Circuit

l

R. G.

8. Output Circuit NO SPECIFIC COLOUR (NTSC)

,

Specific colours are not produced in

colour

Is there a

chroma

of

ICI801

and at pin

signal

at pin

(20) (iX0969CENl) (8) of connector Y2 or BLACK AND WHITE

pin (3) of AD?

Yes

4

NTSC 3.58

No

-

receptron.

*

Check the VCR: TROUBLE SHOOTING

‘RECORD IS IN

(EE colour

I

FLOW CHART NO.

>

mode)

Z-10

When change channel No does colour appear?

YES

1

colour shading.

YES

r-------f

’ IC1801,C1829, ; r I Cl901

l-----

j

----

Check

Q1806

1

,c1801 ;

: ______:

-------,

Norma,

______:

,r

Q1401,Q1803,Q1804,

Check

Line. ( H level at pm (9)

of connector f AG ] in

SECAM Mode.)

Check Pins

SE”M (H)

I I

t

Colour appears but

abnormal colour.

t

I

t

(22). (23), (27)

Abnormal

Signal

When colour control minimum,

colour disappears.

1

No

I

of

ICI801

bias.

I

1

YES

r------------1 I

Re-adjust the

1

white balance. I

L------------J

1

i

No

I

i

,--------l

j ICI801 (iX0969CENl) I ;

X1801 (NTSC

; Q1801-4,6, L__________________4

I

Check

I

adjacent circuits.

L-________-____--_a

Q851

- - - - - - - - -

3.58MHr) ;

1401

and its

_

I

I CheckQ852andits i

I

i

adjacent circuits

I

c_______________--2

r--------1--------,

1

Readjust the white

I

balance.

r - - - - - - - -

I

Check

I

1

adjacent circuits.

I

--------7

Q853

and its

1

I

I I

VT-341 8X VT-5118X

MODEL

FULL ERASE HEAD

L---_---J

VT-3418X

AU010 CONTROL

HEAD

OVERALL SCHEMATIC DIAGRAM

OCNW-0

I60AJZZ

OCNW-0

I45AJZZ

I

OCNW-OIXBAJZZ

1

I

2

I

3

I

4

I

5

I

6

I

-

65

VT-341 8X VT-5118X

PWB-Y

TV MAIN

F83OOPE

PWB-A

OCNW-0

I46AJzi

u

2 3 3 .

5

6 6

I 8

III

OCNW-0147AJZi

OCNW- 8 638PEZZ

I

.I

z 4

5

7

8

7

I

8

I

9

I

10

I

11

I

12

I

66

I

VT-341 8X VT-5118X

MODEL VT-51

FULL ERASE HEAD

18X

OVERALL SCHEMATIC DIAGRAM

OCNW-0

I45AJZZ

OCNW-0

l36AJZZ

M56732L

1

I

2

I

3

I

DRUM MOTOR UN

4

I

5

I

6

67

/

VT-341 8X VT-51 18X

OCNW-0

I46AJZZ

Y

7 z

1

4

5 6 I I

I2

OCNW-0

I47AJZZ

AC=

1

4 5

L T a

-,

XNW-0 I59AJZZ

El4

-1

--2

-3

-4

-5

-6

-7

-8

-9

!iL

XNW-OI49AJzZ

I

7

I

8

I

9

I

10

I

11

I

12

1

68

VT-341 8X

VT-5118X

MODEL

H

G

F

E

R857

[G-DRIVE]

R863

!-zEq

I

VT-3418X

0853

CHASSIS LAYOUT OF TV SECTION

PWB-B

I,

I

01006

cl

III

I

(PWB-B)

r

I

K

H

J

076 I

0762

0

0753

0

075

I

0

1

PW

(PW

01008

O

BB

/

F’

D

C

B

fn

--

01001

0

pETq

(PWB-YE

UNT20

I

l

A

.

69

W-3418X VT-51 18X

PWB-D

AUDIO IN

VIDEO IN

I

B-A ,

0402

cl

Y3

PWB-Y

L

IL-

L

J1401

402

-

AF

r

3

DLl401

Cl

p (Y41 ‘I

:

I

PWB-F

CFl401

T’I 804

DLI80I

AD

I

Y4

l

L5

AE

7

I

8

I

9

I

10

I

11

I

12

1

70

-

MODEL VT-51

H

18X

CHASSIS

PWB-B

LAY0

VT-341 8X

VT-5118X

UT OF TV SECTION

/-

/

G

n

RMC300 I

(AC)

1

(PWB-B)

I

F

E

BB

D

R702

c707

K

I

01008

DA

(PWB-Y)

C

I

B

A

1

R612

I

1

2

I

’ 0602

R526 V-LINI

L60

I

r

ceiTNDTowNI

I

3

I

UP

s50

1

I

[I

0603

I

i

w

5 VA70

I

0202

0

4

I

AU

5

00

/.

IpEET]

I

I (VIDEO)

5 I&%!

I

0

+B 0

0203

6

71

VT-341 8X

VT-51

PWB-D

18X

7

J

VIDEO IN

I I

r-----l

PWB-T

AUDIO IN

[IC3003]

(PWB-T)

PWB-A ‘WB-F) --;

, \

0402

0

Y3

I

I:

AD

DA

.

\

PWB-Y

-

I403

c

00

K

0150

0

1601

0

1

I

a

RI602

j-KEq

Sl40 SERV

0

01802

0

01801

1

01602

CFl601

TP1802

Li

XI

802m

11

Jl4Ol

I

1

i

AF

l-l

3

01451

0

01302

0

DLl401

L-l

01405

u

n

PWB-F

Y4

1

3

l

L5

I

7

AE

I

AG

I

8

I

9

I

10

I

11

I

12

1

72

MODEL

0

Mother Unit

H

G

F

VT-3418X

BLOCK DIAGRAM OF TV SECTION

E

D

,c7cG?

2

C

6

---m----m

I

PHOTO

COWLER

cl

a--

5

.

1

mn,,

ir’

A

1

I

2

I

3

I

4

I

5

I

6

I

73

m-3418X i/T-5118X

VCJ AV

UNIT

7

I

8

I

9

I

10

I

11

I

12

I

74

VT-341 8X VT-5118X

MODEL

17

Mother Unit

VT-51

18X BLOCK DIAGRAM OF TV SECTION

r

t i

=4

I

,-

1

I

2

I

3

I

4

I

5

I

6

75

VT-341

8X

VT-5118X

VCJ AV

UNIT

I

7

I

8

I

9

I

10

I

11

I

12

1

76

VT-341 8X i/T-5118X

MODEL

Cl CRT Socket, Power SW, R/C, Line Filter,

VT-3418X

BLOCK DIAGRAM OF TV SECTION

VCJ,

AN Unit

PWB-F

WB-D

-

2

e-0-e :

-Y

-----

0 PCS”

HER,

1

I

2

I

3

I

4

I

5

----_-.

GNO

i?

,

c

(I

I

6

I

PWB-B

VIDEO / CHROMA / JUNGLE

7

I

8

I

9

I

10

I

11

I

12

I

78

VT-341 8X

I

1

VT-5118X

I

1

MODEL

Cl

CRT Socket, Power SW,

H

G

VT-51 18X

BLOCK DIAGRAM OF TV SECTION

R/C,

Line Filter,

VCJ,

AN Unit

F

E

D

C

PWB-Y

-

L

B

A

-- -z

T

-----

E

RAUP

1

I

2

I

3

I

4

I

5

I

6

79

PWE-8

I 1

VIDEO / CHROMA / JUNGLE

--hr-----

r

I

7

I

8

I

9

I

10

I

11

I

12

I

80

VT-341 8X VT-5118X

MODEL

0

Sound Output Unit

H

G

F

VT-51 18X

BLOCK DIAGRAM OF TV SECTION

E

D

C

B

A

1

I

2

I

3

I

4

I

5

I

6

1

81

VT-341

VT-5118X

8X

DESCRIPTION OF TV SECTION

SCHEMATIC DIAGRAM

SAFEN

I

1.

DISCONNECT THE AC PLUG FROM THE AC OUTLET BEFORE

REPLACE/NC PARTS.

2.

SEMICONDUCTOR HEAT SINKS SHOULD BE REGARDED AS

POTENTIAL SHOCK HAZARDS WHEN THE CHASSIS IS OPERATING.

IMPORTANTSAFEN

BE SURE TO USE GENUINE PARTS FOR SECURING THE SAFETY

AND RELIABILITY OF THE SET.

PARTS MARKED WITH FOR MAINTAINING THE SAFETY OF THE SET. REPLACE THESE PARTS WITH SPECIFIED ONES FOR

MAINTAINING THE SAFETYAND PERFORMANCE OF THE SET.

SERVICE PRECAUTION:

THE AREA ENCLOSED BY THIS LINE( - - - - - DIRECTLY CONNECTED

WHEN SERVICING THE AREA, CONNECT AN ISOLATING TRANSFORMER BETWEEN TV HAZARD OF ELECTRICSHOCK.

CAUTION:

This circuit diagram is original one, therefore there may be a slight difference from yours.

NOTE:

NOTICE:

“‘A” (

WITHACMAINS

RECEIVERAC

)

ARE IMPORTANT

BE SURE TO

-)

VOLTAGE.

LINE TO ELIMINATE

IS

NOTES:

I.

The unit of resistance “ohm ” is omitted.

(K =

7000

2. A//

resistors are

ohms,

M =

IMeg

ohm).

l/8

watt, unless otherwise

no ted.

3.

The unit of capacitance

(p =

,J, P

=

,&I.

4.

The values in parentheses are the ones in the

PB

mode; the values without parentheses are

the ones in the

VOLTAGE MEASUREMENT CONDITIONS:

.l.

DC voltages are measured between points

RECmode.

indicated and chassis ground by

AC 1

IO-24OV, 50/6OHz

“F”

is omitted.

VTVM,

with

supplied to unit and

all

controls are set to normal viewing picture unless

2.

Voltages are measured with

co/our

WAVEFORM MEASUREMENT CONDI-

TIONS:

7OOOO~V,

othefwise

noted.

7OOOO~V

B&W of

signal.

87.5% modulated co/our bar signal

is fed into tuner.

82

WAVEFORMS

VT-341

VT-5118X

8X

MOTHER MOTHER

0

4

2.2

1.5

vp-p

MOTHER

0

9

13

18x

MOTHER

*i-4-

0

3

MOTHER

0

8

,

I

2.0

950

vp-p

Vp-p

(V)

(H)

MOTHER

2.0 Vp-p (H)

0

1

MOTHER

fv

0

6

1.2

Vp-p

(H)

MOTHER MOTHER MOTHER MOTHER

MOTHER

0

MOTHER

ff.-luln-l-L~

0

L

8.8

2

VP-P

8.5 Vp-p (H)

7

165 VP-p

96 VP-p (H)

.

(H)

VT-3418X in-51

m-3418X

VT-51 18x

VP-P (v)

(V)

VP-P

(H)

VT-3418X VT-51 18X

‘.

M

5

55

VP-P

0

MOTHER

0

1010Vp-p

MOTHER

. .

*.

(V)

(H)

0

11

0.47

MOTHER

0

16

0.67

Vp-p

(H)

0

CRT

.O

12

17

0.56

78 VP-p

94 VP-P

Vp-p

(H)

VT-3418X

(kt) VT-5118X

0

13

CRT

0

18

2.6 Vp-p

78

Vp-p

85

Vp-p

(H)

i/~-3418x

VT-51

18X

0

14

CRT

19

0

0.42

78 88

Vp-p

VP-P (H) VD-D fH\

(H)

VT-3418X vr-51 lax

0

15

0.92 Vp-p

(H)

83

VT-341 8X VT-5118X

SOLID STATE DEVICE

-

TOPVIEW

m

SIDE VIEW

TDA7233

6 4

0

a

1

3

FXOO

BASE DIAGRAM

12

1

iX2532CE

32

lL

2SK304CD

B

C E

2SD1555

1

TA7348P

L

BASE

COLLECTOR

EMIlTER

9

321

DTC144ES

iX0640CE

ix0241

iX0257CE

1

2SC1815 2SA1015

CE

L

BASE

L

COLLECTOR

EMITTER

iX0452CE

123

NJM22205

In’

123

2SC3279N PST529D2

I

0

1

STRM6523

1

L

1

EMITTER

2sc2229

I

0

7

iX0249CE

L

BASE

COLLECTOR

.

2sc3399

123

TA78 125 TA7805S

1’

EMITTER

L

BASE

COLLECTOR

PQ30RVll

2SC3620

SElZON

84

VT-341 8X VT-51 18X

r

MODEL

W

Mother Unit

H

G

F

VT-3418X

SCHEMATIC DIAGRAM

E

CCNW--t613PEZZ

”

CRT PYRI 1 - IM” * - Grn

3 -

HITER

4-w

EiE

D

C

0

A

-

1

I

2

I

3

I

4

I

5

I

6

[

85

VT-341 8X VT-5118X

-

7

I

8

I

9

I

10

I

11

I

12

I

86

w-341 8X W-5118X

MOD

n

H

G

F

:L VT-5118X

7er

Mot

Unit-l

SCHEMATIC DIAGRAM

ImE,

IXO249CE

-

E

D

C

B

0753 2XI615(Gl

A

-

1

I

2

I

3

I

4

I

5

I

6

.

87

r

J

I

r

/ I

TUNER

m

w2o1

“‘“’

n 3

30

VT-341 8X VT-5118X

VCJ

AV UNIT

DUNTK830 I

WEV3

I

I I

c

m

I

7

I

8

I

9

I

10

1

11

I

12

I

90

VT-341 8X VT-5118X

MODEL

n

CRT Socket, Power SW, R/C, Line Filter,

DUNTK830

VT-3418X

I WEV I

SCHEMATIC DIAGRAM

VCJ,

1-i

--

AN Unit

DUNTK8373WEV

?

I

1

I

2

I

3

I

4

I

5

I

6

91

/

,

VT-341 8X

VT-51 18X

DUNTK8302WEV 1

DUNTK8303WEV

I

7

I

8

I

9

I

10

I

11

I

12

I

92

VT-341 8X VT-5118X

MODEL

n

CRT Socket, Power SW, R/C, Line Filter,

VT-5118X

DUNTK830

1

I

~;&OlwE”J

OPWBF830lPEZZ

SCHEMATIC DIAGRAM

WEV3

VCJ,

AN Unit

<

e---v----!-l

I’

WI

1om

01302 2SC1815 (G)

I I

’

m

I

i

1

I

2

I

3

I

4

I

5

I

6

r

93

VT-341 8X VT-5118X

DUNTK8302WEV3

DUNTK8303WEV3

7

I

8

I

9

I

10

I

11

I

12

I

94

D

I

W

I

n

I

0

I

m

I

n

I

A

I

pizEizq

QPWBFB407PEZZ

R3006 56 I I /4W)

f

mm

c3004 470 t I6VI

mmll

IX024

m

a003

IO

( I6Vl

ICE

S-ATT

a 9

3.

3. 6

R

3600

2

6

BK

t+

4

+

-llW)

r

m

I

c300 I

IO

---I

I

C3022

5

1 T

C3022

22

(16V)

+

-(16V)

4

1

c303 I 470

JYO

c3029 470 l16V1

,

C3032

.

01 (16Vl (AX)

T

-4,

!

-

C3025

IO

m

R3015

3.9K

C3024 I (J) (ML)

T

R3016

4.7

(DDI

1

SP30 VSPOOBOP-H26A

r

3002

L

044

I

(RI

,a

SP302 vSPOO~OP-H28A

ICE

L_---------------..--

S-VCC

\/T

TO

MAlN(DEl) PWB

GND GND

f&--&&

IZV

TO

s-VOL

MAIN PWB

AF-IN

ml;,

NO74 ICE

w-341 8X VT-5118X

n

Tuner

NOTE: The parts here shown are supplied as an assembly but not independently.

Fi~~~~~~~~~~~~~~~~~~~~~~~~~~

.:+:.:

. . . . . . . . . .

.Y:‘.

~i.........................~.~.~.....~.~.~.~.~.~.~.............~.‘.‘.‘.‘.~.‘..........,..................~.~.

. : : : . . . : : : . . . . . : : : . .

. . : :, i _ :

:‘:..

. : : . :

‘. .>..:.:.:.:.:.:.>:.

:.

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

..~..........................

k-u

AFT

BL p&j

I

BH i:%

OT

l

Infrared Remote Control Unit

NOTE: The parts here shown are supplied as an assembly but not independently.

I

1

I

VTSSSZD

RRMCG1046PESA

1

I

2

I

3

96

I

4

I

5

I

6

I

-~--_--_

_ __.---

D

I

m

I

n

I

t3

I

m

I

n

I

GI

I

1

Memo

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

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

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

. . . . . . . . . ..*...............

. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . ..*.........

.._..................................................................................................................................................

. . . . . . . . . . .

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

. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . ..a.....

..*........................................................*................

. . . . . . . . . .

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

. . . . . . ..*...........................................*

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

..*....................*..............*..............*......................................

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

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

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

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

. . . . . . . . .

..-........................................*..*.........................................*.......................................................................~

. . . .

..*.....................................................*.............................................*..............................*................*...............

. . . . . . . . .

..-......-.........................._............................................................................................................................

..*.................................................................................................................................................

..*...-....-..........................*.....................................................................................

..*...................................................................................

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

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

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

.._.............................................................

. . . . . . . . . . . . . . . . . . . . . ..*......................................

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

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

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

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

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

98

CHASSIS LAYOUT OF VCR SECTION

A/V

JACK

VT-341 8X VT-5118X

TP820

I

S82CE

I

ALL C

El

I

XB

-,-,i”“i

DL550

I

0

05512

PWB-E

0

El

IC560

EA

I

EB

08803

02219

c

I

0

I

Dm

x220

IC8803

IC8802

0

v

02223

0

Y

R2202 EE

LEVEL

I

R220

I

PB-Y LEVEL

Y

IC220 I

TP2;

TP2,

<

CB

r-

I

u

PW?-c

I-

Et

0

07704

I

0

EK

1

I

2

I

3

I

08818

0

4

EM

I

5

I

0

08815

6

99

VT-341

VT-5118X

8X

I

58205 S-VOLI S-VOL A CHV

58204

S8203

58202

CH

,

PWB-J

JB

f==

A

Jcm

Jcd

J

PWB-X

R2203

I

W-CLIP

1 y pp 3

CLIP

R2204

GND

DEVIATION

x550

I

cl

TP5501

TP5502

“Co

GND

s

ciia

-

X5502

I

-.I

J

-I

%%?ER

FL550

l-l

09904

0

PWB-C

~~

&

TP22OI

PB CHROMA

TP2202

HEAD SWITCHING PULSE

0

09905

TP2203 GND

TP2204

REC SIGNAL

R22l2

0

EGK7701

rxj

1

0230

I

0

06607

I

.

I

O0

00

06602

06606

n

cz.

ED

IC660

.

EF

I

EL

II

00800

0

05603

n

v

I

7

I

cl

8

TP660

I BIAS(+)

TP6602 BIAS(-)

Rx4

rl

BIAS

ADJ.

Do

LO660

I

T660

I

F3

09903

IC990

0

I

9

I

100

10

I

11

I

12

1

SHARP VT-3418X, VT-5118X Service Manual

Specifications and Main Features

Frequently Asked Questions

User Manual