Sharp 14VT10X1 Schematic

SHARP

SERVICE MANUAL

S81G314VT10X1

m

VIDEO TV

MODEL ‘I

In the interests of user-safety (Required by safety regulations in some countries) the set should be restored to its original con-

dition and only parts identical to those specified should be used.

CONTENTS

.

SPECIFICATIONS

.

IMPORTANT SERVICE NOTES

i

.

DISASSEMBLY AND REASSEMBLY

.

FUNCTION OF MAJOR MECHANICAL PARTS

.

ADJUSTMENT, REPLACEMENTANDASSEMBLY OF MECHANICAL UNITS

.

ADJUSTMENT OF THE ELECTRICAL CIRCUITRY

l

TROUBLESHOOTINGGUIDE

. BLOCKDIAGRAM ..........................................................

l

SIGNAL FLOW SYMBOLS AT A GLANCE

. WAVEFORMS .............................................................

l

OVERALLDIAGRAM

.

SCHEMATICDIAGRAMS

. WlRlNGSlDEPWBs .........................................................

l

REPLACEMENT ELECTRICAL PARTS LIST

.

EXPLODEDVIEWS

.

PACKINGOFTHESET

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4v

70x1

\

2

3

4 6

.........

B

34

49 69

go 91 95 97

115 121

137

141

SHARP

1

CORPORATION

DISASSEMBLY AND REASSEMBLY

Remove the seven back cabinet fastening

1. screws Remove the one wire fastening screw

2. Remove the one wire fastening screw

3.

4.

Remove the three VCR’s power unit fastening

screws @. Remove the six VCR fastening screws 0 and

5.

remove the VCR with the VCR’s operation.

6.

Remove the CRT’s second anode cap @ from

the CRT.

7.

Remove the “L2” lead wire @ from the CRT

socket unit

8.

Remove the

9.

Remove the TV mother unit with the frame

from the front cabinet.

0.

@I.

CRTsocket

unit

8. @.

@I.

10.

Remove the five TV mother unit fastening screws 0 from the frame.

11.

Remove the two speaker holder fastening screws 0 and remove the holder.

12.

Remove the speaker

13.

Remove the control unit fastening screw and remove the control unit from the front cabinet.

14.

Remove the two control unit fastening screws @ .

15.

Removethe one control unit fastening screw

0.

16.

Remove the four CRT fastening screws

0.

@

DISASSEMBLY AND REASSEMBLY OF THE VCR SECTION

1. Remove the eight VCR holder fastening screws

a.

2. Remove the four upper cabinet fastening screws

8.

3. Remove the seven bottom plate fastening screws

Q.

4. Remove the four cassette housing fastening screws

@.

5. Remove the five main PWB fastening screws

6. Remove the two head amp fastening screws

@. @.

7. Remove the four mechanism chassis fastening screws

@.

8. Release the seven operation panel fastening clips @ and remove the operation upper panel.

9. Remove the six operation holder fastening screws

@.

The VCR power unit removal is described in the

FUNCTION OF MAJOR MECHANICAL PARTS (TOP VIEW)

pole base ass’y

AHC

(fwtomatic

\

@A/C

head cleaner)

head ass’y

($) Cam stitch

23 Dew sensor

x)

Loadi

ng

motor

Full erase head ass’y

Supply pole base

Tension arm ass’

No.

1.

Full erase head ass’y Erase the whole records on the tape in the recording mode.

3.

Tension arm ass’y

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

Bakes 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.

9.

Main take-up brake lever Brakes the take-up reel disk to prevent tape slackening

when the unit is stopped in fast forward or rewind

mode.

10.

Half-loading lever Bring the tape in contact with the A/C head, putting it in half-loading state in the fast forward or rewind mode.

11.

Video search brake lever

It is in contact with the take-up reel disk normally, and brakes

itto

the videosearch rewind mode.

ass’y

Function

a certain degree. It applies larger brake in

au-

\ \

@Half-loading lever

No.

13.

Reverse guide Pulls out the tape in the video search rewind mode, and controls the tape drive train height with the upper

and

lower guides.

15.

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

16.

Pinch roller lever ass’y 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

17.

Master cam 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.

19.

Cam switch Rotates synchronously with the master cam, and detects the position of each mode by means of the

internal switch

23. Dew sensor

An element which detects condensation inside the

unit. This element is activated, when it senses

condensation, to interrupt the mechanism.

-/I

ejectthe

I

(14) Caostan

Function

tape.

Relay

shifter lever

D.D.motor

rer

6

FUNCTION OF MAJOR MECHANICAL PARTS (BOmOM VIEW)

Slow brake lever

Loading relay gear 2

Capstan D.D.motor 3

Reel belt

@-

Relay gear drive lever

o-

0

@

@Take-up

loading gear

IO

Supply loading gear

D

8

-4

AuxiliaFy

brake lever

fast forward

Brake solenoid 5

powerto

Function

run the tape to the reel pulley.

IlO.

1.

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

certain

Capstan D.D. motor

3.

A motive power which runs the tape. It transmits the

power via the reel belt.

4.

Reel belt Transmits the

Brake solenoid

5. Adsorbs and holds the brake shifter in the fast forward Shifts the supply pole base and guide roller via the and rewind modes, and releases it in the stop mode.

6.

Reel pulley

Transmits the power of the capstan

reel disk via the reel idler.

degree.

0

D.D.

motor to the Transmits the movement of the master cam to the

6 Reel pulley

d

No.

7.

8.

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.

Auxiliary fast forward brake lever Brakes the supply reel disk to a certain degree in the fast forward and rewind modes.

Take-up loading gear Shifts the take-up pole base and guide roller via the loading relay gear, and applies the tape around the drum assembly, as well as transmits the power to the supply loading gear.

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

drum assembly.

Relay gear

take-up loading gear via the loading relay gear.

drove

lever

’

7

ADJUSTMENT, REPLACEMENT AND 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 keen the machine in its oriainal

working condition.

replacement, for example).

TOOLS NECESSARY FOR ADJUSTING THE MECHANICAL UNITS

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

0.

AK

Head Tilt Adjusting Jig

Jig Item Configuration

I

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

This Jig is used for setting the

These Jigs are used for checking and adjusting the torque

Remarks

c

of take-up and

A/C

Gauge Head

5

Cassette Torque Meter

6

Tension Gauge (3009)

7

Tens&

Gauge (2.0kg)

Hex Wrench (0.9mm) JiGHW0009 AE

8

Hex Wrench (1.2mm)

Hex Wrench (1.5mm) JiGHWOO15 AE

Alignment Tape (PAL) VROCPSV CD

9

Alignment Tape (NTSC) VROATSV CD

0

Drum Replacing Jig

JiGTH0006

JiGVHT-063 C2

JiGSG0300

JiGSG2000

JiGHWOO12 AE

JiGDT-0001

AW

BF

BS

BG

This cassette torque meter is used

%

Q

6

for checking and adjusting the torque of take-up for measuring tape back tension.

There are two Gauges used for the

tensron measurements, 300 g and

*.okg.

These Jigs are used for loosening or

tightening special hexagon type

screws.

These tapes are especially used for

electrical fine adjustment.

This is used for replacement of the

VCR’s upper drum.

8

-

0.

1

rension Gauge Adapter

-

jpecial

2

Jig Item

Bladed Screwdriver

Part No.

JiGADP003

JiGDRiVERH-4

C-:odc

-

BK

-

AP

-

Configuration

Remarks

rhis Jig is used with the tension gauge. Rotary Transformer Clearance Adjusting Jig.

This Screwdriver is used for adjusting the guide roller height.

Tension Band and Plate

3

9djusting

Torque Driver

14

Box Driver

15

Retaining Guide Height

16

Adjusting Jig

Reverse Guide Height

17

Adjusting Jig

Jig

JiGDRiVER-

JiGTDl200

JiGDRiVER 10-7

JiGDRiVER 10-4

JiGGH-F18

JiGRVGH-F18

-

BM

-

CB

AS

AV

BU

-

c

;“.:;

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

position.

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

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

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

PJC

head and X-

9

MECHANICAL PARTS REQUIRING PERIODICAL INSPECTION

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

inner hole and shaft)

Possible symptom encountered

-atera

noises

-lead occasionally blocked

Door

S/N ratio, no

Door colour,

Sound toosmall

No tape running, uneven No tape running, tape slack

colour

beating

or distorted

colour

Remarks

Abnormal rotation or

significant vibration

requires replacement

Clean with pure high quality isopropyl alcohol.

Clean tape contact part with the specified cleaning

liauid.

Clean tape

with liquid.

Clean rubber and rubber contact area with the specified cleaning liquid.

contact &ea

the specified cleaning

Loadfng Motor

Automatic Head Cleaner

Reel block*

*See

Supply/take-up

Vtdeo search brake lever

Idler gear

Reel Pulley

Maln

NOTE:

-4

the table below for servicing the reel block parts.

reel disks

ass’y

supply/take-up

brake levers

0:

Part replacement.

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).

no

on

0 n

0 0

on no on

0

Lateral image swing

Cassette not loaded or unloaded

See the chart below

No tape running, tape slack

Notape running

Tape slack

Replace the roller of the cleaner when it wears down. Just change the video head cleaner arm assembly for new one.

Clean

with

quality Isopropyl alcohol.

pure htgh

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

10

R,EMOVAL AND REASSEMBLY OF

CASSETTE HOUSING CONTROL ASSEMBLY

0

Removal

1.

Set the cassette ejected condition in the cassette eject mode.

2.

Unplug the recorder from the main source. Follow the procedures below in the specified

3. order. a) Remove the cassette loading belt b) Disconnect the FFC (full Flat Cable) c) Remove the cassette housing installation

screws

0.

d) Slide and pull out the cassette housing control

assembly

upward @I.

~-I-

/==h

- _Q3

Cassette housing

setscrew

0.

8.

Place the unit in the eject mode in removal or

5. 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 ejection.)

MECHANICAL OPERATION CHECK

WITHOUT

When power is on, the general operations of the

mechanism can be checked without a cassette. Note the following points.

1. Check video search rewind and rewind, rotating the take-up reel disk @ by hand (in either

C1I.c G,\-LC ,,,““d.

2. When the stop button is pressed, the mechanism

does

to the eject mode and stops.

3. When the stop button is pressed in the playback, video search rewind, and video search forward modes, the supply reel disk 0 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

!rse

direction). If it is not rotated,

*

works to shift

not

stop at a normal stop position. It shifts

the’Lmechanism

to

@ 0

Insert the tab of the cassette hosing control assembly to the mechanism chassis.

-.

0

Reassembly

Figure 1-l.

1. 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.)

2. Follow the procedures for removal in the reverse order.

Notes:

1. Be sure to unplug the power cord in removal and reassembly.

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.

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.

REpLAC~liACil’ fiC \Il,h”l” \“,,,rrl

ASSEMB

Cassette housing

Cassette housing frame

, E

LY

IVI c IY I

(R)

Figure

u r

l-2.

vv u n WI

VvnrcL

11

0

Removal

1. Unsolder the cassette switch connectors (No. 16,

17) from the stat-t sensor PWB.

/Start

sensor

PWB

r/7

Start sensor fixing hook

Cassete

switch

connector

Figurer

l-3.

2. Lift the start sensor PWB pressing the two start sensor PWB fixing hooks inward.

PWB

5. Place the slider pin just above the worm wheel (Figure l-7). (The retainer of the slider is locked at two positions hen. So unlock it as in the Figure

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

l-8.)

Cut washer

l-7)

-s

witc:h lever

-Qqd

Start

sensor PWB fixing hook

Figure

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

Figure

4. Remove the worm shaft assembly, pulley, and cassette loading belt all from the cassette housing frame (R).

Worm shaft

ass’y

l-4.

wheel

l-5.

Start sensor PWB

bracket

ass’y

-Cassette frame

hosing

(R)

Figure l-7.

_

Slider

Retainer opening

rSlider

(Also provided on the of cassette housing frame)

Cassette housing

i,

Retainer

IL)

side

--Id

t

@

Press.

Cassette housing frame

i

(R) (Ll

side

59

Figure

1-8.

l

Reassembly

1. Turn the phase gear clockwise until the slider comes to a halt in the cassette insertion direction. (See the Figure l-9.)

2. Insert the set up worm wheel gear assembly into the cassette housing frame 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.

(R),

matching the

Worm wheel

Figure

l-6.

ass’y

12

\

Drive gear arm

(4

Figure

l-9.

b)

3. install the pulley and the cassette loading belt on 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.

The mechanism might malfunction if the

lever is slightly out of position. (See page

14.)

Cassette housing frame Ft)

.

worm

c

.,

shaft ass.“-. 1

Cassette loading belt

\

Clutch

\

7

Pullev

7

5. Tighten one B tight screw. Note: Do not over-tighten the

B

tight screw (no more than 5.0 t 0.5 kg.cm), because the lower threads of the screw hole at the resin-made boss can be broken.

6. Place the start sensor PWB on the cassette housing frame (R). Note: Check that the switch connectors (No. 16,

17) are in the cassette switch mounting hole.

7. Finally resolder the cassette switch connector to the start sensor PWB.

REASSEMBLY OF DRIVE GEAR

Worm wheel

Drive gear spring lR)

Reciprocating spring

(4

Drive gear arm

Cassette

‘housing

frame

(R)

shaft bearing

Figure

l-10.

4. Attach the worm bracket to the worm shaft assembly. Place them onto the boss on the cassette housing frame Note:

B

tight

Inset-t 0

before screwing into 8 and

Worm bracket

Cassette housing frame

Figure

(R).

ssette housing frame

Switch lever

l-11.

(R)

0.

(RI

boss

Drive oear

L

Drive gear arm

Drive spring

F

w

oea%

(RI

LDrive

#-

(Drive gear bottom view)

gear arm

Drive gear

spring shaft

(RI

b)

Figure

1-12.

Pass the tip of the drive gear spring

through the square hole of the drive gear (R) to

hook the spring in position. Hook one end 0 of the reciprocating spring to the catch of the drive gear(R).

Hook the other end Q of the reciprocating

spring to the catch of the worm wheel.

insert the pillar @ of the drive gear square hole of the worm wheel. Turn the worm wheel somewhat counterclockwise for insertion

of the worm wheel to the drive gear

(R),

the reciprocating spring is at work.

(R)

into the

because

(R) 0

13

REPLACEMENT OF CASSETTE LOADING BELT

Figure

1-13.

1. Remove the start sensor PWB 0 and worm

’

bracket Q from the cassette housing frame(R).

2. Remove the worm shaft assembly

3. Replace the cassette loading belt @ with a new one.

Notes:

Do not the worm bracket in position. The specified torque is 5.0 + 0.5 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.

overtighten

the B tight screw which holds

kg.cm.

-

Worm shaft ass’y

t

sensor PWB

Worm bracket

8.

1. First make sure that the tip of the switch lever is held at the rib of the drive gear (R).

2. Check that the rib of the cassette housing frame

(R)

and the concavity of the clutch lock lever are

engaged.

3. Finally be sure that the relationship between the clutch lever and the clutch, as well as between the clutch and the pulley, are correct as in the

Figure l-l 5.

Pulley

Check that the clutch is engaged

wtth

0

Resetting

the pulley through the

Figure

1-15.

coupling.

Take the following steps to reset the clutch if it is

unlocked or if the switch lever and the clutch lock lever are unlocked.

lever

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 housing such as the clutch switch lever is in position Note Figure cassette eject mode.

sureenough

that each part in the cassette

If not, it causes malfunction.

:

1-14

shows the position of each part in the

Swtch

level

Rib 2’

Drove

f=Ilb

of cassktre

‘i

gear houslng frame

Figure l-14

‘- Clutch lock lever

(RI

Clutch release

se lever

.~

Figure

Clutch lock lever

l-16.

Rib

of cassette housmg frame

iK1

Shift the slider by turning the coupling in the 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 equipped with a

lock mechanism. Unlock the locks on cassette dousing frame

(L)

and

(R)

side

before shifting the slider.

When the position is set as shown in the Figure

l-

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.

14

REPLACEMENT OF LOCK RELEASE LEVER

0

Removal Place the slider in the cassette down position.

1. (Turn the coupling on the worm shaft clockwise

until the slider is in the cassette down position.) Note: Before shifting, unlock the slider.

Slightly widen the cassette housing frames

2. and

(L)

to unhook the slider holders

(R)

and

(L)

(R)

of

the slider assembly off the grooves of the

cassette housing frames.

(4

4.

Remove the lock release lever

from the slider

holder(R)

l

Reassembly

1.

Follow the steps for removal In tne reverse order. (See Figures Attach the lock release lever to the slider holder

2.

1-17

and l-18.)

I. _I

(R).

Slide the slider holder

3.

(RI

downward so that the

two catches of the slider holder (R) fit the

opening of the slider.

4.

Slightly widen the cassette housing frames, and

set the pins of slider holders

(R)

and

(L)

into the grooves of the cassette housing frames. Note: Check if the pins of the slider holders (R)

and

(L)

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.

Cassette housing frame (RI

Slider holder

(RI

(b)

Figure 1-17.

3. Lift the slider holder the slider by pressing two catches with a thin tip

screw driver. Take care not to damage the catches.

Slider holder

V?

(R)

upward about 2mm off

/Slide

Cassette houslng

Slider holder (Li

lock catch

Slide it upward

about 2 mm.

TO RUN A TAPE WITHOUT THE

CASSETTE

HOUSING CONTROLASSEMBLY

1. Plug in the power cord.

2. Turn on the power switch.

3. Open the lid 0 of a cassette tape by hand.

4. Hold the lid with a pair of vinyl tapes

5. Set the cassette tape in the mechanism chassis.

6. Weight the cassette tape with a weight @ to prevent float.

7. Perform running test.

Cassette tape

8.

here

Figure

Lock release lever

Lock release lever spring

l-18.

15

Wetght to prevent i,,

1500 gi

float

Note:

The weight should not be more than 500

)J

Figure l-19.

.,T

,

. .

.y

.1

>

Mechanism

chassis

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.

0

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 2 1.)

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

(6>.

0.

1-20(b)).

enston ever

l

Removal (Take-up reel disk)

1. Unscrew the screw

cc/

and remove the take-up

reel retainer.

2. Release the take-up reel disk catch

0.

3. Pull the take-up reel disk Q upward.

-

Take-up

reel

disk

Take-up reel ratamer

Figure

l-21.

0

Reassembly (Supply reel disk)

1.

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

2.

Release the supply reel disk catch 8 and back

tension lever

Install a new supply reel disk @ onto the shaft.

3. Replace the tension band @ around the supply

4.

0.

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

(4.

band during installation of the supply reel disk.

2. Be careful not to damage the supply reel disk

aear,

back tension lever, catch, or the like with

Fool;.

ension band

Note

When the tension band is pressed in the

:

direction of the arrow for removal, the catch is hard to be deformed.

t

v

b)

Figure

l-20.

16

/ 0

Q

L I-

rzl

&m

.-c

4

Figure

1-22

Supply reel disk

0

Screw

w

Supply reel

T’

retamer

S‘;bply d!sk catch

ass’y

reel

l

Reassembly (Take-up reel disk)

1. Clean the reel disk shaft @ and apply oil to it.

2. Release the take-up reel catch 8 and video search brake lever

a.

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

4. Replace the take-up reel retainer @ in position

and tighten up the screw

Note

:

0.

Take care not to damage the video search brake

lever.

Clean the reel disk shaft well.

and apply

PJ

011

to

It.

Video search

brake lever

Set the master plane releasmg the reverse guide by a fmger.

Figure l-25.

2. Check that the reel disk is lower than part A but higher than part B. If the height is not correct,

adjust the height adjusting screw (see Figure

26

(b)).

Note

:

Whenever replacing the reel disk, perform the

height checking and adjustment.

l-

Apply a thin ttp drwer to the arrow

releasing for easier

setting

of the take-up reel dtsk

Figure l-23.

posItton In

* After reassembly, check the video search rewind

back tension (see page

20),

and check the brake

torque (see page 22).

l

Height checking and adjustment Note: Place the master plane onto the mechanism unit,

taking care not to hit the drum (see Figure l-24)

1. For height adjustment, press the reel disk with a finger, and turn. it right and left with a

screwdriver

(see Figure l-26 (a)).

Setting

Master plane

/-

lO%O.Zmm

(4

Slide It right and left.

and check contact the reel disk.

r

_

I

&yg_im’+ ‘> .2

Reel disk

I

1

wth

Reel disk

adlustIng 119

height

Mechanism chassis

Figure

(b)

Figure l-26

1-24.

17

CHECKING AND ADJUSTMENT OF TAKE-UP

TORQUE IN FAST FORWARD MODE

l

Remove the cassette housing control assembly.

0

Setting

CHECKING AND ADJUSTMENT

OFTAKE-UP

TORQUE IN REWIND MODE

Remove the cassette housing control assembly.

l

Setting

Torque gauge

Set the scale to

l

Checking

Turn the torque gauge slowly

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

“0”

Figure l-27.

Torque gauge

Set the scale to

Setting

+

ke-up reel disk

l

Checking

Turn

the torque gauge slowly (one rotation every 2 to 3 seconds) by band in the

take-up direction

“0”

Setting

+

Supply reel disk

Figure l-29.

l

Adjustment

700g.cm

The gauge is held a its maximum value.

(Red

Take-up

Figure l-28.

or more

mark)

dIrection

1. If the take-up torque is outside the range, clean the capstan D.D. motor pulley, reel belt and reel

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.

0

Adjustment

Figure

700gfm

The gauge is held its maximum value.

l-30.

or more

at-

w

1. If the take-up torque is outside the range, clean the capstan D.D. motor pulley, reel belt and reel 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.

18

CHECKING AND ADJUSTMENT OF TAKE-UP TORQUE IN PLAYBACK MODE

Remove the cassette housing control assembly.

1. Open the lid of the cassette torque meter, and

2. hold it with a pair of vinyl tapes.

CHECKING AND ADJUSTMENT OF TAKE-UP

TORQUE IN VIDEO SEARCH REWIND MODE

l

Remove the cassette housing control assembly.

Load a cassette torque meter

9

Set value SP 95 ?

30g.cm

Into

the unit

Push the play button to place Push the video the

unit I” the

Place the torque gauge on the supply reel disk, and turn it

lone

rotation

that the torque IS

170+40 g’cm.

playback mode. button to place the unit in the

counterclockwlse

every 2 to 3 seconds) and check

wlthln

the set value

video search rewind mode.

Torque gauge

very slowly

Supply reel disk

Figure l-32.

search rewmd

x;;>

CzY

Note: Set the torque gauge securely on the supply reel disk. If it is not secure, the measurement will be

incorrect.

l

Adjustment

Figure

1-31.

Checking

Check that the torque is in the range of 95 f 30

g-cm.

~.

&.

The toraue 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 SP record mode, and check that the take-up torque is within the range.

l

Adjustment

If the take-up torque in the playback mode is

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

Note: Weight the cassette torque meter to

prevent float.

If the take-up torque in video search rewind mode

is outside the range, replace the supply reel disk.

Note

:

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

19

CHECKING THE FAST FORWARD BACK

CHECKING THE VIDEO SEARCH REWIND

TENSION BACK TENSION

l

Remove the cassette housing control assembly.

l

Checking

@

Remove the cassette housing control assembly.

l

Checking

‘I I\’

e :h’I

4

9

Note

*Torque gaug

‘I I\’

Place the unit in the

fast forward mode.

Place the torque gauge on the supply reek disk, and turn it clockwise very

slowly (one

and check that the torque is within

152

rotation every 2 to 3 seconds)

5 g.cm

Figure l-33.

:

Supply reel disk

Set the torque gauge securely on the supply reel disk. If the torque gauge is not securely set on the reel disk, measurement

will‘be

incorrect.

CHECKING THE REWIND BACK TENSION

l

Remove the cassette housing control assembly.

l

Checking

3

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 (one rotation every 2 to 3 seconds) and check that the torque is within the set value

455 20

g.cm.

Note

couterclockwise

Take-up reel disk

Figure

:

4

Push the video search rewind

video search rewind mode.

Torque gauge

very slowly

u

kzh

l-35.

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

l

Remove the cassette housing control assembly.

Note

Place the

/

rewind mode.

:

unit

In the

Place the torque gauge on the take-up reel counterclockwise very slowly

(one

seconds)

torque is

disk.

and turn It

rotation

every 2 to 3

and check that the

wlthin 152

Figure l-34.

5

g’cm.

Take-up reel disk

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

incorrect.

Capstan shaft

Push the play button to place the

unit In the playback mode.

Tension gauge

1

.aoo-

1,200

g

soon

gauge adapter

Figure l-36.

Detach the pinch roller from the capstan shaft.

1. Set the tension gauge by hooking the tension

2. gauge adapter onto the pinch roller shaft. Gradually release the pressure to allow the pinch

3. 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.

Vinyl tapes

* :&

Place the unit the record mode.

*

I”

2. At the beginning of the tape (E-180), check that the tension pole’s left side is aligned with the supply impedance roller’s left side 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 (left side). Then secure it with the tightening screw.

I

Center

SUPPlY

Tension band

and plate

sung

Supply impedance roller Tension pole

I

ensjon arm

utde roller A

G

Check the

Tenston band

and plate

adjusting 119 settlng

hole

lef-t

echanism chassts

(4

Video

cassette tape

(E-1

80)

Guide roller

B

Tenston band adjustment bracket

Figure l-38.

l

Position adjustment (record mode) 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 (left side). Then secure it with the tightening screw.

I

Supply Impedance roller

TensIon pole

adI1

3e

(b)

Figure l-37.

l

Checking

1.

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.

21

Tenston band adjusrment bracket

/ -

Figure

1-39.

Supply reel

band

CHECKING AND ADJUSTMENT OF RECORD

I

PLAYBACK BACK TENSION

l

Remove the cassette housing control assembly.

Open here

Cassette torque meter

Figure 142. Not used.

/

Push the record button to place the

m

the record mode

unit

Figure

l-40.

chassis

1. Put a cassette torque meter into the unit.

2. Push the record button to place the unit in the record mode.

3. Check that the back tension indicated by the gauge is within the set range 31 to 36

Notes

:

g.cm.

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.

l

Adjustment

1.

If the reading of the cassette torque meter is less

than specified, move the tip of the tension spring hook

pIaYe

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

*

Put a thin screw driver (-) in the shaft hole, lean

6.

it toward you, and turn it for easer shift of the

tension spring hook plate in the direction of A or

B.

CHECKING THE BRAKE TORQUE

l

Checking the brake torque at the supply side

Torque

gauge

/

LA

Tension spring

hook plate

Figure

1-41

Tenston spring

Tension swng

hook plate

Mechanism chassts

22

,-Supply reel disk

Adjust in

the center

Figure

ti

-5:’

the Idler gear

143.

Supply reel

disk

--/

1.

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. Slowly rotate the torque gauge in the clockwise

3. (CW) direction and counterclockwise (CCW) 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 = 280 to 720

CCW direction

=

90 to 230

g-cm,

and that the brake torque in the CW direction is at least twice as high as that in the CCW direction.

0

Checking the brake torque at the take-up side

g-cm,

REPLACEMENT OF MAIN BRAKE

1. Remove the reel belt and the reel block FFC.

2. Remove the cut washer 0 off the brake shifter.

3. Unscrew the four screws C3 and then the

take-

up reel retainer.

4. Remove the reel block assembly @ downward.

5.

Remove the cut washer 0

firstand

then the reel

pulley.

6. Unscrew the two screws @ and detach the idler assembly.

7. Unhook the back tension lever spring

($9

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

8. Open the shifter latch 63 and remove the brake shifter assembly

9. Release the reel disk catches

ED.

Oand

then remove

the left and right reel disk assemblies GD and

10. Finally remove the main brake levers main brake spring

0.

@and

h

0.

Adjust the Idler gear in the center.

Mechanism

1.

2.

chass

Figure l-44.

Remove the cassette housing control assembly. Slowly rotate the torque gauge in the clockwise (CW) direction and counterclockwise (CCW) 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 CCW direction = 280 to 720

gem,

CW direction

=

90 to 230

g-m,

and that the brake torque in the CCW direction is at least twice as high as that in the CW direction.

l

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.

Take-up

reel

retainer

Note

yqg wash/e;-

Figure

145.

:

3

Reel block ass’y

When the main brake is replaced, perform the

height checking and adjustment (see page

l7),

and the brake torque checking (see page 22).

23

R&fCEMENT

Remove the cassette housing control assembly.

1. Place the unit in the unloading mode, and

2.

unplug

0

Removal

Loosen the tilt adjusting screw

1. Remove the azimuth adjusting screw

2. Remove the AK head screw

3. Unsolder the A/C head

4.

the power cord.

OF A/C (Audio/Control)

0.

8.

a.

PWB

soldered to the

AK

head assembly.

Note

:

1. After replacement, be sure to perform the adjustment of the tape drive train (see page 26).

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 NC head screw.

AK

head

PWB

Pay attention to the azimuth spring.

Figure

14.

0

Adjustment

[A/C head tilt angle]

1. Set the mechanism to the loading mode.

2. Place the AK head tilt adjusting jig.

3. Slowly turn the tilt adjusting screw with a screw driver

until

there is no gap between the jig and

the AJC head.

h -A

piecd of white paper

F.

Tilt adjusting

screw

A/C head height

0

Replacement

Figure 146.

AK

head arm

1. Solder the removed A/C head PWB onto a new A/C head assembly.

2. The A/C head assembly is attached so that the A/C head arm and AK head plate are roughly

parallel to each other.

New

A/C head

Never touch the

‘AK

head plate

A/C head tilt

A/C

tiea

I

(4

:rew

driver

Figure

1-47.

(b)

Figure l-49.

24

[AK

head height rough

1 k

adjustment)

80x driver

Roughly

adjust the height of the AK head by turning the AK head adjusting

hexagon nut with the

specialized box driver until

the tape is in the position shown below.

[Height adjustment of retaining

AdJust adjustment

Retaining

&de

adjusting Jg

height

(JiGGIl -

Fl8)

of the retainlnp

guide1

Hdght

the gap d zero between the

jig

(4

Figure l-51.

SdJurtlng

Jig

and the lower flange

guide.

(b)

A/C head-,

[Height adjustment of reverse

Reverse guide adjusting jig

height?

(4

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

spring,

guide and

lift the reverse

sdd

a washer.

-Revewe

guide

guide;

Reverse guide height adjusting jig

Go-end is 13.52 mm.

Not go-end is 13.38

(b)

Adjust the nut visually so that the control head IS

to 0.5 mm below the bottom

of the tape.

Figure

visible

l-50.

J

0.3

HEIGHT ADJUSTMENT OF RETAINING

GUIDE AND 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.

1-51

by using the special

25

&-;arher

*Wing

-Spring

B

@-washer (iron

w Cut

washer

!d

Figure l-52.

0.25and0.13.

flat)

2.1-54.5

ADJUSTMENT OF TAPE DRIVE TRAIN

1. Remove the cassette housing control assembly.

2. Check and adjust the position of the tension pole. (See page 2 1.)

3. Check and adjust the video search rewind back tension. (See page 20.)

4. Set the tilt angle of the A/C head. (See page 24.)

5. Rough adjustment of tape drive train. a) Connect the oscilloscope to the test point for

PB CHROMA envelope output (TP501). Set the synchronism of the oscilloscope to EXT. The PB CHROMA signal is to be triggered by the head switching pulse

b) Loosen the setscrew at the lower part of the

guide roller, and adjust it with an adjusting screw driver (JIGDRIVERH-4) so that the guide

roller turns smoothly. (Do not overloosen the

setscrew, which causes insecurity of the guide

roller.) (See Figure l-53.)

c).Set the alignment tape (See the Notes below)

on the reel disk, and place the unit in the playback mode. (Place a 500 g. weight on the cassette tape to prevent floating of the cassette tape.)

Notes

:

1 Alignment tape.

2 Head

Type-

(TP502).

VROCPSV (PAL) VROATSV (NTSC)

Wrinkles at upper flange

Wrinklesat

lower flange

Clockwise

(4

Counterclockwise

b)

Hexagon

d)

wr

Figure l-53.

Chang:

Figure l-54.

the envelope waveform from MAX to MIN, and MIN to MAX by pushing the

(-) tracking button, and check a flat response

is obtained on the waveform.

e) If a flat response cannot be obtained, roughly

adjust the guide rollers on the supply side and

take-up side using an adjusting screw driver

until a flat response can be obtained.

f)

Turn the A / C head tilt adjusting screw with a

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 Fig. 1 - 55 (a)

2) Wrinkles at the lower flange : Turn the above adjusting screw counterclockwise, as shown in Fig. 1 - 55 (b)

(+)

or

Figure l-55.

Notes:

1. Place the tracking control in the center position, and adjust the X-position adjusting nut so that the PB CHROMA envelop becomes maximum for easier rough adjustment of the tape drive train.

2. In the rough adjustment, pay particular attention to the outlet side.

Loosen theulsetscrew

Figure l-56.

Figure

1-57.

x-position adjusting

nur

26

PB CHROMA l

nvel~f~

(TP501)

mad wnching pulse CTP502)

Figure l-58.

6. Adjustment of A/C head height and azimuth a) Connect an oscilloscope to the audio output

terminal.

b) Use the alignment tape and play back its

audio 6

kHz

signal (monoscope pattern for video signal). Adjust the azimuth adjusting screw to obtain the maximum audio output on an oscilloscope. (See Figure l-59.)

c) Use the alignment tape and play back its

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.

i%

Box driver

Azimuth adjusting screw

Figure l-59.

Figure

l-60.

7. Adjustment of tape drive train and X-Position. a) Connect the oscilloscope to the test points

(TP501) 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

(TP502).

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 CHROMA waveform will take the shape shown in Figure

1-61.

e) Adjust for maximum flatness of the envelope

as the step 5, e) in page 26.

and

4

kz/

Adjustment

When the tape is above the helical lead.

Supply side

Supply

stde

roller rotated in roller rotated in

clockwrse direction

(lowers gurde roller) to flatten envelope

guide

Take-up side

it----y+

Take-upsrde gutde

clockwise dIrectron (lowers guide roller) to flatten envelope.

Figure

i-61.

When the tape is below the helical lead.

Supply side

%=&

Supply roller rotated in

counterclockwtse

direction

roller) to make the

tape float above the

helical lead. The

srde

guide roller

then rotated in the

clockwrse

flatten the envelope.

side guide

(rarses

drrection to

gurde

supply

IS

Take-up side

it-y&j

Take-up side gurde roller rotated

counterclockwlse

direction (raises roller) to make tape float above the helical lead. The take-up

roller is then rotated the clockwise to flatten the envelope.

In

If

e

t

srde

gurde

directton

urde

rn

27

f) Push the ( +) or (-) tracking button to check

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. Push the ( +) and (-) tracking buttons at the

a)

same time to the preset mode.

Rotate the X-position adjusting nut with an

b)

adjusting box driver, and adjust the A/C head position for maximum head switching pulse

low side envelope.

Adjust the playback switching point.

d

d) Check the flatness of the envelope waveform

and sound by playing back a recorded tape.

X-posmon adlustfng nut

l-2mm

2!ilktk

Maw

Figure l-62.

II

chassis

REPLACEMENT OF THE CAPSTAN D.D. (DIRECT DRIVE) MOTOR

0

Remove the cassette housing control assembly.

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 FFC into the capstan D.D. motor control PWB.

3. Attach the reel belt. Notes

:

1.

After installing the capstan D.D. motor, be sure to rotate the capstan

D.D.

motor and check the

movement.

2.

Check and adjust the servo

ciruit.

REMOVAL AND REASSEMBLY OF THE LOADING GEAR BLOCK

Notes : The following explanation is based on

head models. (The slow brake spring and slow brake lever are not provide&on head models.)

1. Remove the cassette housing control assembly.

2. Remove the reel belt.

3. Remove the reel block.

0

Removal

Notes

:

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 l-64.

42-

l

Removal (Follow the order of indicated

numbers.)

Remove the

2

Remove Ihe reel belt

0

Figure

Three

screws

Capsran D.D motor

l-63

L. In

roller with a rubber band or the like beforehand for easier reassembly.

Remove the relay

gear drive lever

Unhook the

slow

brakesorinp 6

28

Figure l-64.

removing the loading gear, secure the guide

.Loadlng relay

Loading relay gear

Capstan D D motor

Remove the slow brake spring Remove the slow brake shaft cap

::

Remove the slow brake lever

3.

Remove the E ring

4.

Rotate the take-up loading gear, take-up

5.

@.

0.

8.

a.

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

a.

Reverse the procedure. Be sure to match the

tally marks on the gears.

Figure 1-66.

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 the 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 shaft cap and supply/take-up

loading gears more than required.

Note

,&

:

Leads

Figure l-67.

Master

Can)

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.

l

Reassembly

1. Turn the master cam all the way counterclockwise.

2. Match the tally mark on the cam switch with the mating mark. Fit the loading block and the master cam

three screws.

with

each other. Tighten up the

Cam

swnch

REMOVAL AND REASSEMBLY OF LOADING BLOCK

0

Removal

leads

1.

Remove the

2.

Remove the

3. Unscrew the three screws

4. Pull the loading

0.

cassette loading

a.

block upward.

belt

8

29

Figure l-68.

3. 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.

Solder

I

o-

Unsolder here

Label

Loadmg

block

Figure l-69.

1.

Unsolder the leads 0 from the lpading motor.

2. Unlock the

left

and right catches

8

of the cam

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

Tally marks

,-Loading

2

8

Catches of cam

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 out the motor.

swttch

Figure

PWB (See Figure

block

PWB

Pull up the cam

the

catches Remove the cam SWliCh

together

with

the

switch pressmg

loading

l-70).

block

l-70.

C9.

1-71

and take

PWB

Note:

Figure l-72.

When press-fitting

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

Figure l-73.

3.020.1

the loading

mm.

3. Set the loading block PWB and the cam switch in position.

4. Resolder the leads to the loading motor.

5. Finally place the loading block (See page

29).

6. Attach the loading belt.

REPLACEMENT OF MASTER CAM

0

Removal

1.

Remove the E ring

2. Remove the half-loading drive lever

3. Remove the E ring

4. Remove the pinch roller lever

5. Pull out the master cam upward

0.

@.

8.

@I.

6).

Pinch roller lever

Pinch

cam follower

roler

level

Motor label

Pa.,1 the :tp oi d

screwdrwcr ilhe here Pry up

the

loadlny

take

0

Reassembly

1.

Remove the loading motor, and mount a new

baLk

end of the

motor and

nut the

or the

motor

Figure

l-71.

3

0

Loadq heir

I

loading motor as in Figure l-72.

2. Place the loading motor so that its label is visible as shown in Figure l-72. Make sure that the screw hole at the motor shaft, protuberance on the loading block, and the motor’s back end marked with the arrow are mated with each other.

Enters the outermost cam groove

30

lever to the

poslllon.~

Slow brake lever cam follower

Figure

l-74

Bottom side of

master

cam follower

unloading

cam-.

Reassembly Place the relay gear drive lever in the unloading state.

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.

a,

Place the half- loading recipro lever’s cam

follower so that it fits in the master cam’s

circumferential cam groove (marked with

arrow), attach the E ring, then mount the half-

loading recipro lever.

4. Turn the master cam somewhat clockwise until 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.

5. Rotate the master cam by hand to make sure all

~-

the four levers (relay gear drive lever,

half-

loading recipro lever, pinch roller lever, and relay shifter lever) are in the cam grooves in place.

6. Mount the loading block.

Notes

:

(See

page 29.)

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.

3. Apply specified grease to the master cam’s grooves and teeth.

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.)

Unsolder the leads.

[2

Head Model1

*

Remove the upper drum by pulling it with the upper drum replacing jig.

Turn and tighten the screws equally.

Figure l-75.

Notes

:

1. Avoid touching the drum surface with bare 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.

31

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. When assembling these parts, do not allow dust

4.

or dirt come between the disk and the upper drum.

Do not use excessive force when driving in the

5. screws.

REPLACEMENT OF

Put the unit in the cassette eject position.

1. Unplug the power cord.

2.

0

Removal (Reverse the order in reassembly.) Remove the

1. Remove the two D.D. rotor assembly setscrews

2.

FFC 0.

D.D.

MOTOR

8.

Pull out the

3. Remove the three D. D.

4.

5. Remove the D.D.

Notes

:

When removing the

1.

stator

assembly, use care not to hit the loading

D.D.

rotor

stator

@,.

stator

setscrews

assembly

D.D.

Q.

rotor assembly or

@.

relay gear.

2.

Secure the D.D. rotor assembly so that the installation positioning holes in the D.D. rotor assembly and lower drum assembly match. Be careful not to damage the upper drum or the

3. video head.

4.

Be sure that the hall device and the D.D. assembly are not damaged by the D.D. rotor assembly or other parts.

After installation, adjust the playback switching

5. point.

D.D.

stator

I2

Head Model]

Figure l-76.

1.

Set the new drum.

2.

Fasten the upper drum in place with the two

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 26.) and the

following electric adjustments. Adjustment of the playback switching point. Checking and adjustment of the X-position

D.D.

stator

setscrew

Figure 1-77.

D.D. rotor

ass’y

32

REPLACING THE AHC

CLEANER)

(AUTOMATIC HEAD

Figure

l-78.

0

Removal

1. Unhook part 0 with a finger in the direction of arrow.

Holir the rib (marked with an arrow) of the AHC

ass’y 8 with electrician’s pliers or the like, and

pull the ass’y upward in the direction of arrow

0.

Note: To pull out the AHC ass’y, hold the AHC lever down.

l

Reassembly

1. Push down the AHC ass’y in the direction of arrow @. Make sure that the ass’y is secured in po-

sition by the hook of part

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 ass’y free of grease or contaminants.

33

ADJUSTMENT OF THE VCR ELECTRICAL CIRCUITRY

Prior to the adjustment:

In most cases, necessity for electrical circuits will

arise from replacement of mechanical parts

including the video head. adjustment of electrical circuits, check that mechanical operation of the equipment is complete (the mechanism are adjusted completely).

0

Instruments

l

VTVM

l

DC regulated power supply

ADJUSTMENT OF POWER CIRCUIT

l

Test points layout

Before starting

l

Oscilloscope

l

Audio generator

If the equipment fails electrically, locate a defect or

defects first of all using instruments. Then repair or

replace parts and make adjustment by the procedures described below.

When required instruments are not available, do

not move controls indiscriminately.

l

Colour bar generator l Frequency counter

l

Alignment tape

0

Blank video tape (VHS)

n

ADJUSTMENT OF POWER CIRCUIT

Adjustment of power circuit

(AT6.5V)

1

Measuring instrument

Mode Test point Control Specification

(1) Connect a voltmeter to

connector PA) and ground.

(2) Adjust

R917

DC voltmeter

E-E C921 $ LEAD R917

8.W +

0.2

C921$

so that the voltmeter reads

(pin 4 of

8.5V.

Figure 2-O.

Adjustment of power circuit

Measuring instrument

Mode

I

Test point

I

Control

I

Specification

(1) Connect a voltmeter to C919@ (pin 1 of (2) Adjust R921 so that the voltmeter reads

(9V)

DC voltmeter

I

1

E-E

C919@

R921

9.4V 2

LEAD

0.1

I

connector PA) and ground.

I

9.4V.

34

ADJUSTMENT OF SYSTEM CONTROUSERVO CIRCUIT

l

Test points layout

Figure

2-1.

SYSTEM CONTROUSERVO

-.W

ADJUSTMENT OF SERVO CIRCUIT

Adjustment of PAL System playback switching

point

Measuring instrument

Mode

Oscilloscope

Playback

(tracking at center) Tape used Test point

Alignment

tape(VROCPSV)

CH-1; TP502

CH-2; Pin 8 of

IC201

(video output). (CH-1 trigger slope switch at ( + ), internal trigger at

CH-1 side)

PWB

Adjustment of NTSC System

point

Measuring instrument

Mode

Oscilloscope

Playback

(tracking at center) Tape used Test point

Alignment

CH-1 ; TP502

CH-2; Pin 8 of

output). (CH-1 trigger slope

switch at (+ ), Internal trigger at

CH-1 side) Control

R753

(60Hz

playbaik

switching

tape(VROATSV)

lC201

(video

SW. P. ADJ.)

Control Specification

R751

6.5 2

(50Hz

SW. P. ADJ.)

0.5H

7.

1. Insert the PAL system alignment tape (VROCPSV) and put the unit in the playback mode.

2. Press both tracking control button at the same time to set the tracking in center.

3. Adjust

R751

(50Hz SW. P. ADJ.) so that the waveform on the oscilloscope screen be as shown in Figure 2-2.

w-2

(Video output)

CH-1

ediv

CH-2;

lV/div

50

pseddiv

Figure 2-2.

Specification

6.5 2

0.5H

1. Insert the NTSC system alignment tape (VROATSV) and put the unit in the playback mode.

2. Press both tracking control button at the same time to set the tracking in center.

3. Adjust R753 (60Hz SW. P. ADJ.) so that the waveform on the oscilloscope screen be as shown in Figure 2-3.

CH-2

(Video output)

CH-1

ediv

CH-2; lV/div

Figure 2-3.

50

pseddiv

35

Adjustment of PAL System slow tracking

Adjustment of PAL System still picture vertical sync

Measuring instrument

Mode

Input signal

Test point Adjusting point Specification

1.

Play back the self-recorded tape in the PAL

System slow mode.

2. Make the resistor R1058 and R1060 circuited with diode in the timer PWB. (Cathode of the diode is in R1060 side)

3. Be sure that the PB mode display

on-the screen.

4. Remove the short-circuit.

5. Adjust the tracking control using the TRACKING button on the main unit or the remote controller

so that there is no noise on the screen.

Adjustment of NTSC System slow tracking

Measuring

instrument Mode

I

Monitor TV Recording and playback on

recording tape. Commercial broadcast or video

signal. Monitor screen Tracking control button No noise bar on the monitor TV

screen.

(b)

Monitor TV

I

1

Recording and playback on

1

recording tape.

Commercial broadcast or video

self-

(+),( -)

short-

disappears

self-

Measuring

instrument

Mode

Input signal Test point Adjusting point Tracking control button Specification No noise jitter

1. Play back the self-recorded tape in the PAL System still mode.

2. Using the TRACKING button on the main unit or the remode controller, make adjustment so that jitter becomes minimum.

3. Now press the STOP button to stop the tape.

Adjustment of NTSC System still picture

sync

Measuring

instrument

Mode

I

Input signal

Test point

Adjusting point Tracking control button ( + ),( -

I

Specification No noise jitter

1. Play back the self-recorded tape in the NTSC System still mode.

2. Using the TRACKING button on the main unit or the remode controller, make adjustment so that jitter becomes minimum.

3. Now press the STOP button to stop the tape.

Monitor TV Still

oicture

1

Self-recording tape

onitor

IM

Monitor TV Still picture playback

I

Self-recording tape

Monitor screen

plavback

screen,

I

(+),( -)

vet&al

I

)

I

Specification

1. Play back the self-recorded tape in the NTSC System slow mode.

2. Make the resistor R1058 and R1060 circuited with diode in the timer PWB. (Cathode of the diode is in R1060 side)

3. Be sure that the PB mode display on the screen.

4. Remove the short-circuit.

5. Adjust the tracking control using the TRACKING

button on the main unit or the remote controller

so that there is no noise on the screen.

No noise bar on the monitor TV

screen.

short-

(b)

disappears

36

ADJUSTMENT OF Y/C CIRCUIT

l

Test point layout

Figure 2-4.

n

ADJUSTMENT OF Y/C CIRCUIT

Adjustment of EE level

f

Measuring instrument

Mode Input signal

I

Oscilloscope

I

Recording

Standard colour bar

(stair-case waveform) Test point Adjusting point

Specification

Pin 8 of

IC201

(video output)

R202 (EE level control)

2.0 + O.lVp-p (not terminated)

1. Set the unit in record mode.

2. Feed the colour bar signal to the video input terminal. Observe the voltage of pin 8 of ~201

on the oscilloscope screen, adjust R202 (EE level

control) to obtain the value indicated in Figure 2-

5.

Y/C

PWB

Adjustment of white clip

Measuring instrument

Mode Input signal

Oscilloscope

I

Recording

Standard colour bar

(stair-case waveform)

1

Test point

Adjusting point Specification

1.

Place the unit to the record mode.

2.

Feed the colour bar signal to the video input

1

TP201

R232 (white clip control)

80+4%

terminal

3.

Turn R227 clockwise to maximum position.

4.

Observing the output at

TP201,

adjust R232 (white clip control) so that the white peak overshoot be 80 + 4%.

5.

Make sure that the dark peak overshoot is 50

10%.

.

2

Figure 2-5.

37

DARK CLIP 50%

z-l

2Opseddiv

Figure 2-6.

Adiustment of FM 3.8 MHz and 4.8

M

HZ

Measuring instrument

Mode

Frequency

counter

Recording

Osci I

loscope

Self-recording/

plavback

I I

1

Adjusting

point

R227 (FM

carrier control) control)

Specification 3.8 2.0 +

Note

MHz +

:

50kHz

Carry out this adjustment only when

beenreplaced

or when the carrier setting (3.8 MHz)

.

R228 (Deviation

O.O8Vp-p

IC201

has

or the deviation (4.8 MHz) is found apparently out of specification.

Make this adjustment after the EE level has been

completely adjusted.

1. First make sure that the EE video signal level is at the specified level.

2. Place the unit in the record mode and get it ready for external input. Note

:

Do not connect anything to the external input

terminal.

3. Hook up the frequency counter to TP205 and

TP202. Adjust R227 (FM carrier control) so that the counter reading be 3.8 MHz.

Note

:

Make sure the white clip control is not now

applied to the waveform.

4. Feed the

colour

bar signal and make

self-

recording and playback.

5. Observe the voltage of pin @ of

IC201

(video output) on the oscilloscope screen. If the playback video signal level is above 2.0 Vp-p,

turn R228 (deviation control) clockwise.

If below 2.0 Vp-p, turn the control counter-

clockwise. Now make self-recording and

playback again.

6. Repeat the above step 5 to finally get the playback video signal level at 2.0 2 0.08 Vp-p, as

shown in Figure 2-7.

t

z.ovp-p

--

1

Figure 2-7.

Adjustment of recording current

Measuring instrument

Mode

Input signal

Osci I

loscope

I

Recording Standard colour bar

h

(stair-case waveform)

Test point

TP301

(GND at TP302) External trigger (video output terminal)

Adjusting

point

Specifica-

tion

R255 (recording FM control)

Sync tip level:

R518

(recording

chroma control)

Red level:

140 + IOmVp-p 24 + ZmVp-p

Note:

TP301

and TP302 are located on the head amp

PWB.

1.

Place the unit to the record mode.

2. Feed the colour bar signal to the video input terminal.

3. Observing the waveform on the oscilloscope

screen (external trigger at pin 8 of

IC201

(video- output)), take the following steps. a) Connect the oscilloscope’s ground and signal

leads to TP302 and

b)Turn

R255 (recording FM control) to min-

TP301,

respectively.

imum.

c) Adjust

R518

(recording chroma control) so

that the red level be 24 + ZmVp-p as shown in

Figure 2-9.

4. Adjust R255 (recording FM control) so that the sync tip be

140 t

IOmVp-p as shown in Figure

2-10.

38

Adiustment of delav level

Figure 2-9.

5OmVIdiv

I Opseci’div

Figure

2-10.

H

ADJUSTMENT OF Y/C PLAYBACK

CIRCUIT

Measuring instrument

Adj usti ng point R240 (delay level control)

Specification

1. Insert the alignment tape and play it.

2. Adjust R240 (delay level control) so that the levels of CH-I and CH-2 are the same as shown in Figure 2-12.

CH-2

Dual-beam oscilloscope

CH-2 level = CH-I level

I

10 pseddiv

Adjustment of playback video signal level

,

Measuring instrument

Mode

Tape used

r

Test point Adjusting point

Specification

1. Insert the alignment tape and place the unit to the playback mode.

2. Hook up the oscilloscope to pin 8 of (video output) . control) so that the on-screen waveform be

2.0 + 0.

IVp-p

Oscilloscope

I

1

Plavback

Alignment tape (VROCPSV) (stair-case waveform)

I .

Pin 8 of

R209 (playback level control)

2.0 +- O.lVp-p (not terminated)

Adjust R209 (playback level

as shown in Figure 2-l 1.

IC201

(video output)

z.ovp-p

IC201

1

I

Adjustment of the APC (PAL)

I

Measuring instrument

Mode

Tape used

Test point Adjusting point C514

I Specification

1.

Inset-t

the alignment tape and place the unit to

the playback mode.

2. Connect the frequency counter to TP504. Adjust C514 (APC control) so that the counter reading

be 4.433619MHz +

Figure 2-12.

I

Frequency counter

Playback

Alignment tape (VROCPSV) (stair-case waveform)

TP504

(APC

control)

1

4.433619MHz f

20Hz.

2OHz

.~

I

Figure 2-l

1.

39

djustment of the APC

Measuring instrument

I

Mode

Tape used

Test point Adjusting point Specification

1. Insert the alignment tape and place,the unit to the playback mode.

2. Connect the frequency counter to TP504. Adjust C518

(APC

control) so that the counter reading

be 3.579545MHz +

n

ADJUSTMENT OF AUDIO CIRCUIT

(NT%)

I

Frequency counter

I

Playback

Alignment tape (VROATSV)

(stair-case waveform)

TP504

C5

18

(APC

control)

1

3.579545MHz It

20Hz.

20Hz

Checking of erase voltage and oscillation frequency

I

Measuring

instrument

Mode

Input signal Test point Adjusting point Specification

1. Place the unit to the record mode.

2. Hook up the oscilloscope to both ends of the erase head.

3. Make sure the erase voltage is over 40 Vp-p.

4. Be sure that the oscillation frequency is 70 5 5kHz.

Oscilloscope

Recording

Both ends of the full-erase head

Erase voltage; Over 40 Vp-p Oscillation frequency; 70 fi 5

kHz

full-

‘L

Figure 2-13.

Adjustment<of

Measuring

instrument Mode

Input signal

Test point Adjusting point

Specification

1. Play back the alignment tape signal).

2. Hook up the VTVM to the audio output terminal.

3. Adjust R610 (playback level control) so that the output level be - 9 + 1

playback level

AUDIO

PWB

VTVM

Playback

Alignment tape

(VROATSV) (1

-kHz

level control signal)

Audio output signal

R610 (playback level control)

-9tldBs

(I-kHz

level control

dBs.

5 Useddiv

Figure 2-14.

Adjustment of bias current

Measuring instrument

Mode

Input signal Test point Adjusting point Specification

1. Place the unit to the record mode.

2. Connect the VTVM to TP601 (SIG) and TP602 (GND).

3. Adjust R630 (bias current control) so that the bias current be 260 t 1 OyA (2.6 + 0.1

VTVM

Recording

TP601 (SIG), TP602 (GND)

R630 (bias current control)

260 + 1

OuA

(2.6mV + 0.1

mV).

mV)

40

Checking of recording level

Adjustment of the AFT

Measuring instrument

Mode

Input signal

Test point

VTVM

Self-recording/playback

1

kHz/-8dBs

Audio output terminal Control Specification

1. Feed 1

kHz,

-8 2 3dBs

-8

dBs

signal to the audio input terminal. Make self-recording and playback of the signal.

2. Make sure the output at the audio output terminal is - 8 f 3

3. If out of

~.

bias current.

H

ADJUSTMENT OF THE IF CIRCUIT

spec,

dBs.

readjust the playback level and the

Adjustment of the RF AGC

Measuring instrument

Oscilloscope Signal generator

PIF

Input signal

frequency uniwave

Colour bar signal (70 dBu)

Test point

Pin@of

IF Pack(GND)

Pin @ of IF Pack (Video Output)

Adjusting point

TOO2 (AFT coil)

Specification

1.

Receive the

strength: 70

2.

Using the signal generator, feed the

frequency

colour

dell).

(36.87SMHz)

bar signal (input field

signal (sinewave) to the

tuner IF output terminal.

3.

Set the tuning switch to the VHF or UHF position.

Keep the tuning button

(+)

or ( - ) depressed until the beating on the oscilloscope screen be minimum. .

4.

Set the tuning switch on the normal position.

Adjust TOO2 (AFT coil) so that beating on the

oscilloscope screen be minimum.

PIF

Mode

Input signal

Test point

EE

Colour bar signal

Pin@of

IF Pack(GND)

Pin @ of IF Pack (Video Output)

Adjusting point

1. Receive the

VROOl (AGC

colour

bar signal (input field

control)

strength: 80 dBu).

2. Observe the video output terminal waveform on the oscilloscope. Adjust

VROOI (AGC

control) in

the IF pack until the noise disappears from the

oscilloscope screen and the waveform nearly comes into sync.

Just

before shrtnking

RF AGC

AFT

IF Pack

Figure 2-15.

41

l

Chassis layout

(K

IO041

540 I

& SEkSw

ADJUSTMENT OF THE TV ELECTRICAL CIRCUITRY

I

I!

I

I i-l

DL4OI/ j )

II

(K

IO031

CZI J-y----

-

/

AUDIO IN

ICE0 I

I

.LI

Figure

3-1.

Mother PWB

I

CRT

Q

R-BIAS

G-BIAS

I

B-BIAS

3

Figure 3-2. CRT Socket PWB

42

G-DRIVE

B-DRIVE

VIDEOKHROMA ADJUSTMENT

CRT cut-off and Sub-Brightness adjustment

l

R853: R- bias control

l

R859: G- bias control

l

R865: B- bias control

l

R857: G-drive control

l

R863: B- drive control

Note:

Prior to this adjustment, warm up the unit with the beam current of more than than 30 minutes

Receive “MONOSCOPE PATTERN” signal with

1. pattern generator. Set R857 (G-driver control) at CENTER

2

position Set R863 (B-driver

contol)

position. Set R853 Set

(R-biascontrol)

R859

(G-bias control) at

at MIN

Set R865 (B-bias control) at MIN

Set the control at the “Normal” position that

3. contrast is Max (15x15), colour is center and brightness is center (7/15) using control,

Aand v

Set the screen control at MIN (O/l 0) position.

4. Turn on

5.

line

Connect the oscilloscope to TP852 (Red

6.

keys.

5401

position.

(service switch) at the horizontal

cathode).

7.

Adjust the sub-brightness control (R425) so that the blanking pulse on oscillosope is 10 + 1 Vp-p.

, ,

nFl”p-p

600uA

for more

at CENTER (5/10)

(O/10)

position.

MiN (O/l 0)

(O/IO)

position.

(5110)

(7/l

5)

3.

Set the brightness control at MAX position.

4.

Connect beam ammeter to TP601 and TP602. (Full scale: 3mA)

5. Adjust the sub-contrast control (R436) so that the beam current becomes approx.

0.8mA

(rough adjustment).

6. Adjust the drive-control

(R857,

R863) so that the

colour temperature is at 7500°K. (High beam:

0.8mA)

7. Adjust the contrast control and brightness

control so that the beam current is about

200pA, and check that the colour temperature

is at 7500°K. If the temperature is not at

7500”K,

go back to “CRT cut-off adjustment” and repeat the adjustment.

(X =

0.300,Y 5 0.310)

h

Sub-contrast control: R436

Note:

Prior to this adjustment, warm up the unit

with the beam current of more than

600uA

for more than 30 minutes.

Receive “MONOSCOPE PATTERN” signal with

1. pattern generator. Set the Contrast controls at MAX position.

2. Set the brightness control at MAX

3. Connect beam ammeter to TP601

4. TP602 Adjust R436 so that the beam current becomes

5.

(+).

(Full scale: 3mA)

positin.

(-)

and

0.8mA.

8.

Slowly turn the screen control clockwise and

stop

it where the horizontal raster appears

slightly, in one of the three colours.

9.

Carefully adjust the vias controls of the other two colours until the horizontal raster becomes white.

lO.Turn the screen control counterclockwise until

the horizontal rester disappears, and stop it.

White balance/Back ground

0

R857: G-drive control

0

R863: B-drive control

l

R436: Sub-Contrast control

Note:

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

600).1A

for more than 30 minutes.

1. Receive “MONOSCOPE PATTERN” signal with pattern generator.

2. Set the Contrast control and MAX position.

43

PAL

chroma

adjustment

Note:

Before this adjustment, the

PIF/AFT/AGC

adjustment must have been completed.

l

R806: 1 H-delay amp control

l

T801: 1

H-delay phase control

Receive “PAL COLOUR BAR” signal with colour

1. bar generator.

Connect the following resistance matrix to

2. pins 0 and @ of the connector

(K),

to which

an oscilloscope is connected.

To osci”‘z\t

;::53

(pin @ of

2;!f

Resistance Matrix

K)

3. Set service switch

S401

at the Video Cut position

to cut off the Y signal.

4. Adjust the colour control key so that the output waveform of colour difference signal becomes

1.5 vp-p.

5. Adjust R806 and T801 so that the output waveform shown in Fig. a is corrected to that

shown in Fig. b.

6. Return

5401

to CENTER (normal position).

PAL

Sub-colour

adjustment: R802

1. Receive “PAL COLOUR BAR” signal with colour bar

generator.

2. Set the control at the “Normal” position that contrast is Max. and brightness is center

(15/15),

colour is center (7/15)

(7115)

using control, A

and v keys.

3. Connect oscilloscope to the TP852 (Red cathode).

l

Range:

l

Sweep time:

2OVIdiv

2Opseddiv

4. For PAL colour bar signal reception, adjust R802 so that the white output (75%) and red output will have the same level.

CY

Mg

a

G

Figure

a. Waveform before the adjustment

Figure b. Waveform after the adjustment

Sub tint: R882

1. Feed “NTSC COLOUR BAR” signal to video in jack with colour bar generator at the AV mode.

2.

Connectoscilloscope

3. Set the TINT VR

to TP853 (B-Y).

(R1098)

at the center

(5110)

position.

4. Set service switch

5401

at

the Video Cut position

to cut off the Y signal.

5. Adjust colour control key to obtain the output of about 3 Vp-p.

6. Adjust sub tint control (R882) so that the output waveform is as shown in figure below.

7. Return

5401

to CENTER (normal position).

Y

w

Same level for the

R

whbte

and ted outputs

Same level-,

8-Y

*,-’

‘w Y

I

.

-

cv c

-

I

’

MQR B

1

/

-

,

I

ADJUSTMENT OF

Note:

l

During the adjustment, keep the unit facing the

east.

DEFLEmON

LOOP

Focus adjustment

1. Receive “MONOSCOPE PATTERN” signal.

2. Set Contrast control at NORMAL position.

3. Set Brightness control at NORMAL position.

4. Adjust Focus control to have best focus at the central area of CRT.

Adjust

point

Horizontal

* This adjustment should be performed after the

purity and convergence adjustments.

1. Receive “MONOSCOPE PATTERN” signal.

2. Adjust R602 so that the horizontal center of picture is at the position which gives the relation of A = B shown below.

centering

control: R602

Vertical linearity control: R526

1. Receive “MONOSCOPE PATTERN”

2. Adjust R526 so that the vertical linearity of picture is at best point.

signal.

Vertical size control: R503

1.

Receive “MONOSCOPE PATTERN” signal.

2.

Set the Brightness control and Contrast control

at MAX position.

3.

Adjust R503 so that the vertical size of picture is

at the same size as horizontal size.

0

Vertical size: 9% TYP (Max. 11%)

Vertical centering control:

*

This adjustment should be performed after the

purity and convergence adjustments.

1. Receive “MONOSCOPE PATTERN” signal.

2. Adjust identical to CRT geometrical vertical center.

5501

so that the picture’s vertical center is

5501

45

PURITY ADJUSTMENT

Note:

l

During the adjustment, keep the unit facing the

east.

Purity

adjustment

1.

Prior to the purity adjustment, warm

with beam current of more than

up

the unit

500pA,

for

more than 30 minutes.

2. Receive the green signal alone and adjust the beam current to about 500uA.

3. Fully degauss the CRT with the degaussing coil.

4. Before the purity adjustment, It is needed to

roughly adjust the static convergence.

5. Set the purity magnet

at

the position which gives

zero (0) magnetic field.

Adjustment:

6. Observe the green spots

microscope as shown in Fig. purity magnet so that they are at the specified

landing position.

(“a”

and “b”) with a

3-3.,

and adjust the

The beam landing IS shlhed to right.

Figure 3-5.

The beam landing IS shifted to

kfl

Figure 3-6.

RlQht

Figure 3-3.

7. If the right and left green spots are both deviated outwards from their landing positions as shown in Fig. 3-4 push the deflection yoke forwards until their positions are corrected.

Left

,

# I 1 I

, ,

\

The beam landing is shifted

outwards.

Figure 3-4.

9. Adjust the purity magnet so that the beam landing is correct at either of the centeral part, right and left parts of screen, then check that the green beams at four corners of screen are all correctly positioned.

Finally, check that the beam landing at any pat of screen is satisfactory with the Rank “B” specifications.

10.

If the green beam is positioned to mix with the

other

colour,

pull the deflection yoke

backward.

l

Outside of the specified landing: To front of the deflection yoke

l

Inside of the specified -landing: To back of the

deflection yoke

11.

Receive

“MONOSCOPE PATTERN” signal or

“CROSSHATCH PATTERN” signal.

12. Set the raster rotation at

“0”

position (with the

unit fasing the east.)

13. Tighten the screws of the deflection coil. Tightening torque: 11 kg + 2kg

8. If the beam landing is shifted to right or to left as shown in Figs. 3-5. and

3-6.,

adjust the opening degree of the purity magnet so that the beam landing is correctly positioned.

46

CONVERGENCE ADJUSTMENT

Note:

l

During the adjustment, keep the unit facing the

east.

Convergence adjustment

This adjustment should be performed after the

purity magnet adjustment.

1.2.Receive crosshatch pattern signal with pattern

generator. Set the Brightness control at CENTER position. Set the Contrast control at MAX position.

Wedge

magner

/

CRT neck

J

-

\

I-pole

IIHI

Convergence in Fig. 3-8.:

Insert wedges

(b)

and

(c)

between the deflection yoke and CRT, and tilt the deflection yoke downward until the mis-convergence shown in

Fig. 3-9. is corrected.

RGB

I

Convergence in Fig. Insert wedge

(c)

deeply between the deflection

!

Figure 3-8.

3-9.:

yoke and CRT, and tilt the deflection yoke to right until the mis-convergence shown in Fig.

3-

9. is corrected.

T-l--b

Lacquer

0

Static Convergence

3.

Adjust the opening degree of the 4-pole magnet and rotate the magnet to converge red and blue

lines.

4.

Adjust the opening degree of the 6-pole magnet and rotate the magnet to converge red, blue and green lines.

0

Dynamic convergence

c

2.

Dynamic convergence (convergence of the three

colour

fields) at the edges of CRT screen is

accomplished in the following manner.

l

Convergence in Fig. 3-7.:

Inset-t

wedge (a) between the deflection yoke and CRT, and tilt the deflection yoke upward until the mis-convergence shown in Fig. 3-7. is corrected.

BGR

\I,

Figure 3-9.

Convergence in Fig. 3-l 0:

Insert wedge

(b)

deeply between the deflection yoke and CRT, and tilt the deflection yoke to left until the mis-convergence shown in Fig.

3-10

is

corrected.

I

Figure 3-10.

II ‘1

6. Stick the three wedges onto the CRT, and apply glass tapes thereon.

7. Apply lacquer to the deflection yoke screw,

magnet unit (made of purity, 4-pole and 6-pole magnets) and magnet unit screw.

I

Figure 3-7.

Blue signal and check that there is no mixture with

the other colour signal.

47

After the adjustment, receive either the Red or the

CRT DISPLAY ADJUSTMENT

Note

:

l

During the adjustment, keep the unit facing the

east.

Sign position control:

1. Select channel

RlOOl

“2”.

2. Receive “CROSSHATCH PATTERN” signal.

3. Press the Mode OSD button on the Remote Controller.

4. Adjust shown below.

5. After adjustment, confirm that there is no defect in the on-screen characters with no signal and

AV

*

The error in the settlement of charactor position

must be

RlOOl

to obtain the sign position as

mode.

b>a.

a: the range of the error in the settlement b: range between two crosshatch vertical lines

Ailgn

the right edge of channel number with crosshatch’s vertical line from right.

third

48

TROUBLESHOOTING FLOWCHART

MECHANISM OPERATION FLOWCHART

*

CASSETTE

Cassette

inserting

Half-loadmg

INSERTION *STOP

I

Loading and

master

I

Does cassette control clutch wthin 2.5 I~C. turned

Are start/end ~“sors at before c7wette

Half-loading

tape.

This flowchwtdcwrikr the not

give

For cam switch poritlons. se4 Fig.42

Insert UIIene.

1

Turn

off

cassette switch.

+

motor

staN in normal direction

cam clockwise.

+

after

off?

lever

Is cam switch at FF position?

Loading motorstop~.

tome off

cassette switch has

high level

insertion?

YES

workstodrawout

its

details.

outline

of

the mechmirm’s operation. but

I

Cassette isejected and loading motor rtopr.

I

loading and master cam counterclockwise.

1

(Cassette is judged caught

NO

(Cassette LED or some

judged defective.)

1

does

t

4

Cassette

switch

turns

on.

t

motor turns in reverse dwectlon

t t

halfway

)

other part

is

STOP +

REUPIAY

I

Press REOPLAV key.

I

Loading

motor

Es

turns in normal direction

I

1

I

Tape loadmg

Pole base works

Pinch

I

Is cam switch

I

1

I

Capstan

motor

todraw outtape.

roller

comes

intotontwt.

at PE

positto”?

t VES

t

Loading motor stops.

YES

turns in normal direction.

I

NO

I

Unloading

7

t

I

+

Picture appears

I

I I

PLAY +STILL

PLAY + VSR

VSR + PLAY

Slow

brake

prewng

Press STILL key.

Loading motor turns in normal directtlon

1 and

mestercam

1

Slow brake comes into contact

chx;!se.

with

End

Press REW key.

I

Pmch roller relearmg

Idler

wmging

Loading motor turns in

and master am clockwise.

Is tern switch

Turn capstan motor m reverse dIrectIon

{

1

Turn loading

1

notmsldirection

at PU

posItion?

lNO’

YES

Stop loadmg

motor in

motor

1

I

reverse dvection. 1

I

Loading motor turns in reverse direction and master cam counterclockwise.

Press PLAY key.

4

+

Set

capstan motor to pleybeck

I

speed

+

Pinch roller prerrmg

I

Press pinch roller.

YES

1

PLAY -3

VSF

Set capstan motor to search speed

I

Stop loading

Set cspnan

I

t

motor to

+

i

motor.

search speed.

YES

NO

I

Unloading

1

REC /PLAY + STOP

PressSTOP

I

key.

1

STOP

--B FNREW

1

Is

cam

witch

at FF

I

position7

N

l-4

Tape unloading

Brakelatching (9)

Stop capstan motor in about 5 sec.

f

stop capstan motor.

.

I

Stop loading motor.

Turn capstan motor in reverse direction.

NO

Check 1 : Is

Release brake solenoid and brake reel disk.

Turn loading motor in reversedirectmn.

Release brake taking steps ‘brake

Turn capnan motor in normaldirection.

Check 2 :

t

Stop drum motor.

1

*

YES

1

t

take-up

reel

puke outputted?

t YES

stop capstan motor.

4

t

1

t

latching (‘1)‘.

t

Irtake-up

reel

pulseoutputted

$

YES

stopcapstan motor.

End

,pe

slack

detecting

I

End

l Z:Tape is judged to be

.

I

and EJECT and be accepted. First check take-up see detector functions. The when the output is specified. This is taper

End ‘2

any other key-in than

reel

ifthe tape

tape is

agamst damage.

slack

POWERcannot

pulse

output to

slack

ejected only

as

to

protect

the

Press FF/REW key.

FFIREW

and

mastercam~ounterclockwae.

L

Turn loading motor in normal direction.

YES

End

rake latching

’ I

operation

iid

FF/REW -s

I

Brake function

:

STOP

Stopcapstan motor.

Release brake solenoid and brake reel disk.

T

End

1

+

J

1

STOP + CASSETTE EJECT

Preu

EJECT key.

Half-loading bringing-back

lever

Stop Ioadmg

t

End

I

motor.

Fia.4-1

cam switch pattern

The cam switch has 4-l. The circuit turns on when the signal comes on the shaded zones on pattern system controller in order mechanism modes.

t

olete

Clutch

change

FFREW(STOP)

0

signals

Main brake

the pattern as

are

judged

l

shown in Fig.

the

witch. The six

to bc on or off by

to

detect

ncrgiied

LO PLAY VS.REy

Master

the

360’

cam

Pinch

turning

roller

activated

El

Fia.4-2

The relationship

I*’

Rclrtionrhip

bctwcen the

q

between tam

7

cam witch positions

” [yQLL

fipu

witch positions

Cam

and

rnd the

mechanism movement is

mechanism

switch

pattern

\

Tcrmin*l

movement

No.

*how” in

Fig 4 -2

1. FFIREW

MECHANISM

FAILURE (NO TAPE WINDING)

TROUBLESHOOTlNG

YES

:

2.

1

REVPlAY

Is brake shifter at PLAY position?

FAILURE (MODE RELEASE)

Remove cassette

controller, turn

power on and press PB key.

(REC)

1

YES

NQ

Brake shifter is

deformed. Replace.

Is brake shifter at NO

-

PLAY position? - shifter.

1

YES

Replace relay

’ [yH?h

overloaded due to damage on tape. Damaged tape is

deformed. Replace

Check for broken NO Clean solenoid solenoid lead (turn power off, disconnect FFC and check with tester).broken

YES

I

[ Replacesolenoid.

v

-+

while attracted, or

replace it.

No

lead)

1

Are idler gear and

reel disk PB gear in mesh?

L

NO

H

I

Replace idler assembly.

I

L.

Is take-up reel disk

pulse outputted 1 - turnmg

YES

Check main PWB.

NO

Is capsten

Is 5V applied at reel PWB

1

t

DD

YES

?

I

NO

AreVco

- “cc 5V

1

ReDplace

NO

12Vand NO

applied

2--t

YES

‘I

capstan

Disconnect and

reconnect main

FFC.

3. WINDING FAILURE AT VSR

4. UNUSUAL SOUND IN EACH MODE

I

:

I

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

Go to 2.

Istake-u normal NO

during p

Is

VSR

ayback ? -

P

YES

Press VSR key. (Turn

take-up reel disk by

hand.)

brake shifter at

position

?

1

NO

--j

FAILURE routine.

shifter.

REUPIAY

Replace brake

--T=---1

t

Does idler gear

I

YES

lssuppl

reel disk

rl

torque etween

140 and 200 g-cm?

I-

1

YES

--f

NO

Replace supply reel disk.

Insert cassette and press PLAY and STOP keys repeatedly.

Check for rattling

loading/unloading.

I

Isreeldiskheightas

specified (using jig)

I

,

Is

no unusual sound

heard at FF

‘14’“““‘*”

NO .

1

YES

ower

ON

FF

keY

IN

1

JFe?s

REW key and turn take-

h;q;&;ey.

Replace L block sub

“,~%?l)&!~ing

Re;ii;.st

t-l

I I

Turn take-up reel disk

slowly with finger.

NO

Are take-up reel

stopper and

rubbino

_I

block)

reel

drsk

‘ear

PB

5,

each ot er

?

1

I

h

1

NO

Replace take-up reel stopper.

H

-1-,-

Is no unusual sound heard at REW?

YES

r

F

t

I

/ $s$,%$$s%

R Replacecapstan

DD.

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

in

Unplug

the

AC

Replug it a

Is the

fuse resistor R904

Are the ATl2V normal

Is the

Are the AT5V

properly connected

Is the PC

Is the PC 9V

at

power

few

minutes

and

?

AT 5V line normal

and GND lines

JVFC

5V line normal

+YES

line normal

JYES

@of IC701

cord.

later.

t

lVEC

AT6.5V lines 1

YES

LVFC

with IC801 7

iYES

lVEC

(lX0972GE)

I

alright ?

?

VCR

POWER TROUBLESHOOTING

The

VCR is

dead.

I

NO

____L

ND

NO

Check

the

NO

I

NO

*

+

*

Replace

the

fuse

resistor.

Check short I”

)

servo

transistor etc.

AT 5V line and IC805

~

(AN78N05).

I

Check

(TA8757AN)

adjacent

I

the

PWB,

Check poor soldering.

Replace

Check

main

fuse resistor and

trouble in the

ICBOl

and/or

4706

and Q9901.

9902

and lC902 (M5237L).

pin@, @of ICSOI

and X501,

parts.

(fsc

circuit)

PWB

Dower unit.

X502

FLOW CHART NO. l-1

and

FL801.

I

and

I

i

Is the

key switch in good contact

JYES

Is there

short-circuit in

input?

Are pulses

=I--]

Check iC801, IClOOl and signal line

recewed at pin

JYES

the

key

@of

t

Does

the infrared remote

function ?

remote

control

I

Is

“L” pulse given

the receiverwhen the infrared

remote

control is

I

away from the

Is there input of lC801

set

no

short-ciicuit in the

IClOOl (IX060BGE) or

(IX0806GE) ?

{YES

receiver ?

JYES

out

of pin

activated ?

YES

?

control

KEY-IN TROUBLESHOOTING

Key-in input is not received.

I

NO

?

(NO

INFRARED

No

infrared remote

@of

key

R/C

operation is

ND

I

NO

TROUBLESHOOTING

possible

control.

I

1

.

Check the switch contact.

Check

IC801

w

(IX0608GE) and switches for poor soldering

I

from the

Replace control as required.

Check

I

Check pin is

okay, replace

Reposition exposed to strong light.

(IX0806GE), IClOOl

ChecklCB01,lC1001.

I

the infrared remote

the

AT 5V and GND

@of

IClOOl.

the

receiver.

the

set not to be

Check all

the

terminals.

FLOW CHART NO. l-2

I

1

FLOW CHART NO.

lines.

I

Ifthe

1-3

Check

IClOOl,

IC801 and signal line

Are

.

I

the

cam switch and cassette

slider properly positioned

)VES

Does

@of IC801

change

from

the

Does to tape is

I

Does pin@of level

inserted

Is the loading cassette

I

Does IC801

to

“L”

is

loaded?

1.5V to OV level

cassette

tape is

YES

pin@

of IC803

“Ii”

level

when the

inserted

?

LVES

IC803 go to

when the

cassette

?

IYES

correct

voltage at the

terminal

when

tape is

inserted

JYES

Replace the loading motor.

J.

start

sensor

when

pulse at

the cassette

(IX0806GE) change from “H”

level

(IX0806GE)

inserted

(8A6209)

cassette

tape is

the

?

A

cassette

pin@

CASSETTE

A cassette

?

when

?

go

“II’

of

tape

CONTROL TROLlELESHOOTlNG

tape is

not

taken

in.

NO

I

NO

I

NO

tape is taken

NO

in, but ejected at once,

I

Check thewayuptopina of

Check pin@of

Check loading motor.

Check way up

I

i’

Check

the

cassette housing.

Reposition

the

cassette switch and all

IC801

and all

IC803.

Check IC803.

between

IC803 and

the

start sensor and all

to IC801.

FLOW CHART NO.

cam switch.

IC801.

theway

the

up

the

1-l

when the

EJECT button

Does

the take-up

when the

capstan

running

Is

reel pluse at pin

when the take-up turning

7

to

Is

pulse at pin

(IXOB06GE) disk is

Is ‘H’ (BA6209) when reel inputted 1

Is “H’

Is the

loading

Replace etc.

when the take-up

turning ?

level at pin

level at

correct

motor terminal ?

Does

the loading motor

the

cassette cam, gear,

LOADING MOTOR

)YES

reel disk

motor is

?

)YES

@of AM

reel disk

@of ICBOl

fYES

@of

IC803

pulse

)YES

pin@of ICE03 ?

YES

voltage at the

+YES

)YES

is pressed

turn

socket

is

reel

has

been

run

AND

EJECTTROUBLESHOOTlNG

A cassette tape fails to eject.

?

FNO

NO

vNo

NO

?

I

See FLOW CHART NO.

Check the

reel

Check

i

~

*

between socket and all and

4804.

Check IC801.

Check IC803.

Check between ICE03 way up to

Replace

disk and reel drive

the

reel

sensor.

pin @I of

the way

up to ICBOl,

and

the

loading

the

loading

FLOW CHART WO.

l-7.

AM

all the

motor.

,-a

-

Does

cassette switch

of

IC801

2.5V level

rb*/

change

when the

pulse at

from

1.5V to OV to

cassette

tape is

@

Check the cassette switch and all thewayuptolC801.

1

SYSTEM CONTROLTROUBLESHOOTING

Are

serial clock pulse and

data

pulse applied to

@I of IC801 (IX0806GE)

IClOOl (IX0608GE)

pins @and

from

?

timer

YES

Are

system control

system control ready pulse applied NO to

pins @and @of

data

pulse and

ICI001

from

IC801 ?

IYES

Does

power

control

(L) @of IC801 “H” level

change

?

pulse at pin

from

“L’ to

+VES

from

“L”

to

“H’

?

I

change

from

“H’

to

YES

“L”

?

YES

No

power.

FLOW CHART NO.

1-6

CAPSTAN

I

MOTOR

TROUBLESHOOTING

The capstan motor fails to

run.

FLOW CHART NO.

1.,

I

NO

(IX0972GE) ?

Check IC701.

YES

Is PC

SV at pin

@of

41

Check IClOOl and IC801.

MC socket

7

Check

the PC

5V line.

I

+YES

Check R713

up to

1

Check

w

IC701, and and lC801.

Check

NO

*

Check way up to IC801.

Check IC801.

49909

properly and all

the

Is 2.5V at

I

socket

7

Is the voltage at socket

about 2.W 7

@of

+YES

YES

+YES

MC socket

@of

MC

?

Itid

I

IsAT lZVatpin@of MCsocket?

NO

I

Checkthepin@of

I

Check

49902.

IClOOl.

1

Replace

the

YES

capstan

motor.

R714and

line.

MC socket and

all

the 2.5V

between the

pins@, @ and@ of

Checkthe AT

12V line.

the way

MC socket

IC801.

1

I

DRUM

MOTOR TROUBLESHOOTING

The drum

motor

fails to run.

d

FLOW cn*Kr NO. 1-a

fIX0972GE)

I

socket

IC701

I

Is PG MM

Is H. SW.

I

?

(IX0972GE)

signal at

pulse at

Replace IC701.

AYES

YES

$-YES

?

+YES

pin@

iYES

pin@

#YES

The drum

of IC7017

of

IC701 !NO-

I

motor

I

NO

runs

only for

a

*

I

Check

*

IC701, and

and

Y

I

few

seconds.

Check all (IX0972GE).

L

Check

MM

It801

Check

the way up

control).

Check IC701.

between the

Check the AT 12V line.

between the

IC701

between the

(IX0806GE).

the

drum motor.

to

pin@of iC701

Readjust

Check IC701.

MC socket and

MC socket

ME socket and

R751 (PG

I

1

CAPSTAN SERVO

*

Capstan servo does not function.

TROUBLESHOOTlNG

FLOW CHART NO.

I-10

Only P8 mode inoperative.

mode inooerative

Check the pins 0, and adjacent circuits (X501, X502, etc.) at Y/C NO

PWB, and check the line between Y/C PWB PAL

and pin@ of

lC701.

@of KS01

(TA8757AN)

Check the capstan signal line between the harness AM-MC and

Q709.

H

FG

Is there the clock input atPir

IC701 ? 4.1

in NTSC mode; level about O.Mp-p).

Does there appear

t

biir-

i%$zin

mc

de. 3.58MHz

I

*YES

?

l

I

Does there appear

CTL

signal at pin

of

E

-

IC701 (IX0972GE) ?

*NO

Does CTL

amplifier circuit of to @) operate

normally

I

Adjust the height of the AK head.

I

1~701

?

Do pms@to @of IC701

operate normally

Does the A/C head operate normally

NO

the circuits around

JVES

YES

(pins@ YES

YES

@

I

Check

-+

?

the line

between pins

pin@of IC701.

Replace A/C head.

@and

Is there capstan APC

Check the capstan

&,

I

Check

YES

“a’.

t

I I

t

Check

I

‘@‘.

I

Only REC mode inoperative.

I

G

I

Does there appear the composite sync. at pin

+I

1

t

1

@at RI701 ?

+YES

I

N

t

I

TAKE-UP

REEL PULSE

Insert put the unit in FF REW

GENERATOR TROUBLESHOOTlNG

the

cassette, and

or

mode.

FLOW CHART NO.

l-11

HEAD SWITCHING

PULSE

TROUBLESHOOTING

FLOW CHART NO.

See FLOW CHART NO.

Replace

IC701.

l-12

l-8. 1

Is there the pulse at pin 0 of connector

reel sensor

the

MF

?

IN0

Replace

the (located in the sensor PWE. F2977GE).

reel sensor

reel

Check MF.

the

harness

AM-

about

0.45 Vp-P

about 25m Vp-p

Are the drum PG drum FG outputted to

@ of the

Check the harness AG-ME and

then replace the

signals

pins

plug AG.

and

@and

1

Check

5

drum FG signal lines

between the IQOZ?

the drum PC

plug AG and

and

VCR RECORDING

MODE (LUMINANCE) TR~UBLESHO~IING

FLOW CHART NO.

l-13

VCR RECORDING

MODE (CHROMA)

TROUBLESHOOTING

FLOW

CHART NO. 1-14

t

Does a normal appear in E-E mode ?

Is there a

of

IC201 ? (TP201)

Is there a of

IC301 (BA7252S or

XRA7252) 7

Are pins@and @Of IC301 at OV level and level

I I

picture ND

YES

I

*

signal at pin @

signal at pin @NO

YES

v

?

YES

9V

ND

IC201

of

IC201

Is there a

of

lC201

I

No record.

(AN3248NK) ?

+YES

?

YES

signal at pin @ND

?

t-l

I I

Check IC203 (AN78NOS) and

the

PC9V line.

Check R202

ADJ.).

Change

Check R232 (W. clip ADJ.).

Check R255

t

ADJ.)

Check

Check BIAS 9V

(E-E

level

FL201 (LPF).

(REC

YES

Q213andQ214.

the

AL PB 5V and

lines.

FM

LEV

Record is in black

Is there

a signal at pin

of

RI501

(TA8757AN) 1

(Video

signal)

1

of IC501

7

IYES

0

and white

Check

the

Colour B

& W

PB mode -.--- 4.6V

heck

a of ICSOl?

b

Colour -.

B&W. . . . . . . .ov

(

I

DC

level at

mode-

mode - DCOV

$-YES

the

DC level at pin

2.4V

E-E

>

colour

mode

).

Check IC203 and

the

PC9V lines.

Check

the E

(0505).

Check

Q503 emitter

- frequency4.433619 MHzPAL,

3579545

Check

the

IC501 and

(AN78N05)

5V line

MHz-NTSC.

ABNORMAL

pins 0, @

adjacent

of

Is there

a signal at pin

of

IC301

@A72525 or XRA7252), when (REC

FM ADJ.)

minimum.

to

R255

6-j

NO

t

pals at

Ir-2rll

IYES

VCR PLAYBACK

I

NO

MODE (LUMINANCE)

No

Playback. ,,

Is there

5V at pin

lC301

?

Is there H. of ICI301 ?

Check of 4301

SW.

Pat

YES

Replace IC301.

peripheral circuit

and

4302.

A

TROUBLESHOOTING

@of

pin @

N0

t-l

,

i

I

Check line.

I

Check (AN78N05)

FLOW CHART NO.

the H.

SW. pulse

Q201,

IC203

and PC9V lines.

(-15

vcR

PLAYBACK MODE (CHROMA)

Playback is

i

Is there a

signal at pin

of

IC301 CBA72525

XRA7252) ?

+YES

(TAB757AN) ?

of

I

IC501

I

I I

?

of

lC501

NO

@

or

Check

* is

the

5V (AL PB 5V line) and

adjacent

Check

the

[XAJ torCE 1

I

.

Replace IC501.

I

Is there

a signal at pin

of

DL501 or

ntoumsHoonr4G

in black

and white.

I

pin 0 of IC301

circuit of IC301.

harness

from

JYES

aof

DL502.

FLOW CHART NO. l-16

J

I

N0

@

Check

4513

and D505.

I

of

lC201

Check from

I

4401

ECJ to

?

YES

and harness

l

VCJ

Replace IC201.

I

Replace IC201.

I

1

Check

9401

from r ECJ to 1 VCJ

and harness

Replace lC501.

Replace IC201.

1

r7yz-j

VCR

E-E MODE

Check

TROUBLESHOOTING

the

harness

from r

VC 1 to r

FLOW CHART NO.

ECI

and signal line.

l-17

) Is there SV at

lC201

?’

Is there

a signal at pin

of

lC201

?

@of

NO Check

NO

@

4203 (AN7BN05)

and

the

PC9V line.

Check R202

Check

the

@ of

lC201 DC

(E-E

level

DC level at pin

“L’

level.

VCR SOUND TROUBLESHOOTING

FLOW

CHART MO. I-111

EE

0

Check the

‘L’

IC601

level at pin

in

the=

EUREC

@

of

Check

5V line.

I

Is there Bias Oscillator

signal

of T601 (Bias Oscillator)

Check the between and Audio Head.

at

pinoof IC601 7

NO SOUND

REC

9

at pin

RECSignal

pin@of KS01

@and

1

YES

<

EE sound is heard

But Audio REC is not possible

NO

YES

line

Check the Bias CTL 9V line,

@

-

about 7V at

and Bias Oscillator

?

Check the

pineof

Check the signal at pin

parts.

>

pin@of lC601

(4602).

‘L’

level at

IC601.

IYES

t

at pin

Checkthe Audio Mute

line.

@of IC601

and adjacent

@of

YES

IC6011

YES

pin@of lC601.

~~~~~~h~MainPWB.

1

Check the

IC351

(IX0241CE) and

Check the Audio mute circuit; Q6601 and 46602 on

IC352

(TDA7233) on

,

,”

TV

.

II

TROUBLE SHOOTING TABLE

F701

Check

+

Normal

FLOW CHART NO.

Blown

+

Replace

the Fuse

out

2-l

Circuit to be

l.TUNER

2.

PIF

3.Automatic gain control

4.9V

BVideoswitch

Check adjacent

+ B2

ICBOl

power

and

parts.

checked:

source

NO

PICTURE, NO

I

Does

the

noise level increase at max. Contrast,

Brightness,

and

Sound Control?

SOUND

1

FLOW CHART NO. 2-2

m

r-------

I 1 f

I L------------------J

--v --_----

CB54,

CB55

Check

c

the Tuner BL, Bn, Bu + B2 biases. +

82 must be

8~ must be band switch at VL position. BH

must be

band switch at Vu position. Bu

--~

I I

must

band switch at Vu position.

approx. 9V.

approx. 9V with the

the approx. 9V with the

Normal

i-i

i

Check

the

I

circuit.

L----------------l

Tuner

i 1 CheckthelFpack. i t 1

and

L-------------..-A

r

(

-------:

Check the speaker, lC352 and JllOl

(Phone)

Circuits to be checked:

l

IC801

and

l

itsAdjacent

R.G.B.

Output Circuit

:------------------’

I :-x80_‘_[%&:_4_3..Hl)_l

1

IC801 (IX0969CENl)

Circuit

!

NO SPECIFIC

Is there a signal at pin ICE01 (IX0969CENl) and at pin @ connector VC?

No 15 some coiour

produced in BMI

broadcast reception?

COLOUR (PAL)

chroma

Specific colours are not produced colour broadcast reception.

I

Yes

Check TROUBLE “RECORD IS IN

AND

WHITE

mode)

1

@of

of

Yes

r------------------~

f

Readjust

I

balance.

L------------------d

the

VCR:

SHOOTING

1

t

the white

(EE

in

BLACK

colour

FLOW CHART NO. Z-3

4

1 I ,

Circuits to be checked:

l

ICE01

and

Circuit

l

R.G.B.

;--------------------. f

I0301

j 4807 ; X802 (NTSC358M) j

its Adjacent I

Output Circurt

-.

(IX0969CENl)

NO SPECIFIC

I

NO /;;;;r;;;;aytduced

j

i

COLOUR

Is there a chroma

at

pin @ of IC801

(IX0969CENl) a of

connector

+YES

reception?

(NT-SC)

Specific NTSC 3.58

signal

and at pin

VC?

I I

1

coloun are not

reception

I

NO

-

YES

Is the white

I

YES

FLOW CHART NO.

produced in colour

from Video In Jack.

Check

the VCR TROUBLE

SHOOTING “RECORD

IN BLACKAND WHITE

(EE

colour mode)

balance properly adjusted?

r---________________-----~

i Readjustthe white :------------------------:

IS

1

NO

+

balance

24

I

f

i”,qi r------------------~

!

Check

Q8Sl

and

circuits.

its

! adjacent L------------------A

pijzffy

1I Check ! i adjacent

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

4852

circuits.

and

F!

I

Check Q851 and

1

adjacent

its

i

I

Check

4853

! adjacent

circuits.

L------------------d

and

its

! I I

L-------_______-_----~

circuits.

its

I I I I

L_--__-_____________-~

Check adjacent

Q852

circuits.

and

its

I I I I

._______-_--_________:

Check adjacent

4853

circuits.

and its:,

I

NO VERTICAL SCAN

.

II

I

Normal

Q

IC801 (IX0969CENl) Pins @ and @

t

biascheck

FLOW

C”A.RT

NO.

FLOW CHART NO. Z-5

I

NO

Does

waveform appear

atpin@ofIFpack?

I.

1

I

f

Abnormal

r----------‘-----------

A-1

26

-

1

Normal

:--------------------------, I

I I L__________-_-------_______1

C512

:--------------------------,

I

: - - - - - - - - _ _ _

,-------------------------,

, I I L-~~~~~~~~~~~~~~~~~~~~~~~~~

I # 8 I

lC801

_

T------

t

Abnormal

I

R625, D605 C622, C503

------1

i

:

Check

D713,

I

and R720

:____________________:

L705,

W52

i

;

7 r--------------------~

i

Check lC352 and

! adjacent L-----~-~~~~~~~~~_~~~~

I

Check IC801 and adjacent “NO

1

parts.

NO

PLAYBACK PlCllJRE

parts as same

PICTURE’.

NO PLAYBACK SOUND

I I I I

FLOW CHART NO. 2-7

I

as

FLOW CHART NO.

24

OVERALL BLOCK DIAGRAM

69

I

7

I

a

I

9

I

70

10

I

11

I

12

1

SERVO PROCESS BLOCK DIAGRAM

A

0

‘------------------------------?

“-REF.

1

SERIAL

,CBOl 43PIN

AH

C

I

DECODER

-IF-

PB ON

G

H

1

2

I

3

I

4

I

5

I

6

i

--------------------------------------------------------~

1

r--‘---‘----“-----------------------------------

T

I

i L-------------------~-~----~ I---,,-,---

I

------------------------------------------------,

---------1

:

‘<

I

7

I

a

I

9

I

72

10

I

11

I

12

1

I I I I I / I

I_--------J

1---------y

u

RECORDING CHROMA BLOCK DIAGRAM

A

B

C

E

F

ED

5

VIDEO INPUT

10 5

BVFFER REC/PE SW 0509

q

I

l----l

I

CARR. B.P.F.

NTSC

4.2 I

MHz

I 1

i--------____---__-______

L-----AL

I

COUNT DOWN

EF

9

CHROMA

ROTATION 9

G

H

1 I

2

I

3

I

4

I

CB

5

I

6

I

3 Pin IS

used 05 selector

ierrmnal on

--------------,

EE(RECVPB

FROM

/

BURST

30OmVp-p

R518

LUMINANCE BLOCK

REC FM

CE

I REC SIGNAL

TO HE0.D *UP

BLOCK

xn

I

-L p.

“dD”J. CHRoMA

I

/

COUNT DOWN

-+!+qTt

I

fSC

^...

TO BASE OF

0221

,

/ ,50,ihI

h

CB

7

COMPOSITE

SYNC

EF

IN 7

c513

TP504

CA

4 SERVO 60

1%

ED

4

RECORDING LUMINANCE BLOCK DIAGRAM

5v

R202 EE

LEVEL

AILl.

cp

r-

4------------------

2

c20 I

171,

______~

yr

I

SERVO BLOCK

FROM MAIN BLOCK

EG

h

1.8

H.SW.P.

FROM MAIN BLOCK

EH

26 VIDEO ,NP”T W

/ 1 “p-p)

>20 I

r-----7

+&+a

jH.P.FHLIN

EE

(H)

FROb

EG

SK57

20

BLOC

CD 2

FROM

CD

24

L LEVEL LO-, “,

u LEVEL 12-3”) GRAY H

LEVEL N-5”) :BLACK

.THROUGH

F” PVLSE

EH

24

SYSTEM CTL BLOCK

1

I

2

I

3

I

4

I

5

I

6

I

/

z--yJ-&-

ICE0 I AN3248NK “DE0 SIGNAL PROCESSOR

I

FROM CHROMA BLOCK ,EM,TTER OF 0504,

I

7

I

8

I

9

I

78

10

I

11

I

12

1

PLAYBACK

CHROMINANCE

BLOCK DIAGRAM

BURST I SDmVp-p

TO PIN12 OF ICZOI

PB CHROMA

BURST

300mVp-p

EF

FF CB

15 / MESECAM

IH)

BURST ZOOmVp-p

r____~_-----------,

I

t

/j-

CB

18

r/

) KILLER

I I I

I , I I I / L--------------------~~~~,

“J”L

INV.

Y

n7

H

jE

PB AMP.

I

I-------,

I

------

’ E F./SW 1&14/512

SIGNAL

T

I

AMP.

’

Q510-I

I I 1 I I / , I I L~~~~~~~~~~----------------------------~------

T

i

T

c505 I

IC50 I VHITA8757N/- I CHROMA

I / I I

/ /

’

L MESECAM

$

/ I

DL50 I NTSC AMP. COMB FILTER

DL502 PAL

COMB

FILTER

PROCESSOR

ACK

B-ID

llFT

*i ( ‘i

J

I

0513 E.F.

\

ID LOGIC

TOBASEOF0211~ 21s ICCD CLOCK)

ED

SERVO 60

4

1

I

. __ _.-

CA

4

2

I

3

79

I

.-_

i

T

4

I

5

I

._

6

I

.--

50mvp-p

H

NTSC

ACC DET

-FL

4.43

0508

EIURST I

OOmVp-p

FROM HEAD AMP. BLOCK

PB CHROMA

COMPOSITE

XA

5

EF

SYNC. 7

I?502

‘4-J &03 c50’I

5

TP504

Fj+>

I

7

vco

--------------------------------~

R50 I

-&o,

‘:

I

T0

SERVO BLOCK

I

qk

I I I

a

I

9

0505 INV.

I

10

I

11

I

12

I

80

PLAYBACK LUMINANCE BLOCK DIAGRAM

R240 DELAY LEVEL AOJ.

47

L.P.F

L207”v208 C234 -237

L LEVEL IO-I”, THROUGH

M

LEVEL 12-3”) GRAY

H

LEVEL 14-5”) SYNC

Ey$IJ

BLOCK

rTYP.z.oVP-P)

-----------

T pc5”

RZIZ

R21 I

h

lir I

____

----------------Q$-------------

MUTE

1 i

S”B

CLAMP

I

C-MIX

I

PB

I I

---- -- -----------;

APT CTL

NC MIX

1

I

SUB-

TRUCTER

t

I

1

I

2

I

3

I

4

I

5

I

6

I

81

. . .

___ _

% CCD Charge Cowled Devce

F---Y

:C251

71

h

,260mVp-p)

L---___-____-----__-____________________-------------------------

ICE0 I

-

IOC

n TP203

AN3246NK VIDEO SIGNAL PROCESSOR

DOC

EN” DET

It

c227

PB FM

IJJOmVp-p)

‘7

R209

PB LEVEL ADJ.

EE

IL)

INV. 0202

FROM SYSTEM CTL BLOCK

EG

2

*I

cc.

I

7

I

a

I

9

I

10

I

11

FROM SYSTEM CTL BLOCK

I

EG

2

12

I

82

.-

___.--..

N

“’ “’ 1 , ~FC ,

w

P

m

.,.“,,.

..-,-

z I

- ?3?’ I

i

---------I

i

r-----i

)%nna AMP.,

0)

u

C306 ~304

K=+-

A C304

T

lC30 I VIHBA72525/- I OR

HEAD

AM’

VHIXRA7252/-

x

4 AL PB 5”

I

xn

5 PEI CHROMA

CE

4

CE

3

CE

5

x*

7 PB FM

CE

7

CE

2

TIMER BLOCK DIAGRAM

ici WI I~C1XoexGEZI TlVER CONTROL

r-------------------------

2

r

----me-.

E

ii

I/

I

&-i---Ii

1

I

2

I

3

85

I

4

I

L-----------------------

5

I

_

6

. I _ ^.-.-

I

-----

8

N.C

I

-

t

m m

11

I

88

10

I

7

I

8

I

9

I

12

1

l^_.-..

J

BLOCK DIAGRAM

8

__--_------

{ a@ @I

@l(vA)

I ’

::

e

a

B h

1

C

I(

VIDEO/Cl

D

E

F

G

H

1

I

2

I

3.

87

I

4

I

5

I

6

I

IC35

I

AUDIO

ATT

5 7 3

I

Jl 1 I

KS0 I

VIDEO/CHROMA/JUNGLE

K

IO041

I

I I /

TMR

/

3

9

IC45 I VIDEO SWITCH

B

3

111

8

VW0

IN

I

OUT

I

7

AL010

I

&%’

SELECTOR 4 2

6

9

I

s

‘E-

PCS”

”

5--

BL

*E-

BH

“clBu

I

10

I

11

I

12

I

88

SCHEMATIC DIAGRAM

SAFETY NOTES:

1. DlSCONNECT THE OUTLET BEFORE REPLAClNG PARTS.

2. SEMICONDUCTOR REGARDED AS POTENTIAL SHOCK HAZARDS WHEN THE CASSIS IS OPERATING.

AC

PLUG FROM THE

HEAT

SINKS SHOULD BE

AC

NOTES:

7. The unit of

1000

2. All

resistors are

no ted.

3. The unit of P

=J.w?.

4. The values in

PB mode; the values without parentheses

the

VOLTAGE MEASUREMENTCONDITIONS:

7. DC voltages indicated and chassis ground

AC230/240V,

controls unless

2.

Voltages are measured

or co/our

WAVEFORM MEASUREMENTCONDITIONS:

1OOOOjfV

signal is

resistance

ohm, M = 7 Meg ohm).

l/8 watt, unless otherwise

capacitance

parentheses

ones

in the

are set to

otherwise

87.5

fed into

REC

mode.

are measured

5OHz supplied to unit and all

normal viewing picture

no ted.

signal.

percent modulated co/our bar

tuner.

“ohm” is omitted (k=

“F” is omitted (p

are

the

ones in the

between points

by

VTVM, with

with IOOOOpV B &

=pF,

are

W

CAUTION:

This circuit diagram is original one.

there

may be a slight difference

a9

from

Therefore

yours.

MAIN CIRCUIT

m

Playback Chrominance Signal

m

Playback Luminance Signal

0

E-E Signal

0

Audio Playback Signal

Y/C CIRCUIT

m

Playback Chrominance Signal

m

Playback Luminance Signal

m

E-E Signal (Video)

SYSTEM CONTROL, SERVO CIRCUIT

m

Drum Error Voltage

@

Drum Frequency Comparison Signal

m

a

m

@

a

Recording Chrominance Signal

Recording Luminance Signal

Audio Recording Signal

Recording Chrominance Signal

Recording Luminance Signal

Capstan Error Voltage

Capstan Frequency Comparison Signal

w

Drum Phase Comparison Signal

HEAD AMP CIRCUIT

m

Playback Chrominance Signal

(ps.y

Playback Luminance Signal

AUDIO CIRCUIT

0

Audio Playback Signal

m

Audio Recording Signal

m

Playback Control Comparison Signal

@

Recording Chrominance Signal

e

Recording Luminance Signal

0

E-E Signal (Audio)

J: 1

C201

.ovp-p

PIN5

REVEE

Y/C

-u”

v:z.ovp-p IC201

PIN9

VCR WAVEFORMS

J:O.EiVp-p

REUPB

C501

PIN 17

REUEE

v: 1

.ovp-p

lC201

PIN21 PB

V:700mVp-p

TP201

YIC

I,

V:350mVp-p IC20 1

PIN28

REUEE

lV&

PB

Y/C

k---H -

V:240mVp-p 4504

EMITTER

PAL

Y/C

I

H:3.579545MHz H:4.433619MHz

v:

l.zIVp-p

TP504 fsc

REVEE

(NTSC)

(PAL)

f/C

i/:

220mVp-p

2504 EMITTER REC’EE NTSC

Y/C

V:4.8Vp-p IC201 PIN1

COMPOSITE SYNC.

Y/C

LfH

V:800mVp-p

BURST

IC501 PIN12

Y/C

400mVp-p

PB

‘L

V:ZOOmVp-p TPSOI PB

CHROMA

----+I

lV>

I

Y/C

l-14

d:440mVp-p ZE

CONNECTOR

REC SIGNAL

PIN1

REC

HIA

I,

V:

14OmVp-p

TP301 REC

HIA

l--r

2v -

V:4.8Vp-p

HEAD SWITCHING PULSE

XA CONNECTOR PIN3

REUPB

91

iERV0

SERVO

-

1:3.58MHz (NTSC)

-I:4.43MHz J:O.3Vp-p

C701 PIN42 REUPB

SERVO

I: 1080Hz

-i:757Hz (PAL SP) 4:

1.7vp-p

4M

CONNECTORPIN

CAPSTAN

WDIO

(PAL)

(NTSC

FG

fsc

SP)

L---J --+I

v:o.ltvp-p

AG CONNECTOR PIN6 PB DRUM PG

SERVO

V:3.2Vp-p

IC701

PIN36 PB CTL

AUDIO

l-2, -4

v:z.ovp-p

IC701

PIN7

REUPB

DRUM PG

SERVO

v:s.ovp-p

IC801

PIN4 EE (REC)

V-SYNC.

AUDIO

w

H:720Hz H : 600Hz

v:

IC701

DRUM FG

AUDIO

H:70 + 5kHz V:

TP60 I( + ),

REC

(NTSC)

(PAL)

1.9vp-p PIN9 PB

7.35mVp-p TP602( - )

H:lkHz V:160mV K602

PIN8

REUEE

w

H:lkHz

V:

160mV

K602

PIN1

REUEEIPB

1

w

H:70 t 5kHz v:7ovp-p

BA CONNECTOR PIN4-5

REC

92

TV WAVEFORMS

AOTHER

j) Z.OVp-p (H)

/lOTHER

MOTHER

@

8.8Vp-p (H)

MOTHER

m

MOTHER

@ z.ovp-p (V)

MOTHER

J7.h

MOTHER

@ 2.2vp-p (V)

MOTHER

il

‘:

3 55VP-P

dOTHER

3

13Vp-p

dOTHER

(V)

0-0

@

1 .ZVp-p (H)

MOTHER

@ 1 OVP-P

MOTHER

(H)

@ 165Vp-p (H)

MOTHER

(i?J

0.47Vp-p

(H)

MOTHER

@ 95OVp-p

MOTHER

@

0.56Vp-p

MOTHER

(H)

@

2.6Vp-p

(H)

@

0.42Vp-p (H)

@

93

0.92Vp-p

(H)

@

0.67Vp-p (H)

-1

.

_-l”_-l” ._--_ _-

CRT CRT CRT

TTin

0 78Vp-P 0-O

@

78Vp-p (HI

J? Ll-T

@ 78Vp-P U-0

:

OVERALL DIAGRAM

HEAD AMP PWB-J

AUDIO UNIT

SERVOSYSCON PM-K cunx3(LBoT~

VCR. MAIN

Y/C

UNIT

PWR-c oum(l*Z~TusO

VCR POWER PWB-P RDENCWBDGELZ

CRT PWB PWB-H

-

SYSTEM CONTROL, SERVO CIRCUIT

D

A

UDIO/CONTROL

IF

G

I

PWB

.OAO,NG MOTOR PWB

L

0

‘yo901,

1

l

VOLTAGE MEASUREMENT MODE

PB

.......

REC

Parentheses (

......

Without Parentheses

I

1

2

I

3

I

4

I

5

I

6

I

97

MAIN CIRCUIT

(DUNTK:

1

VOLTAGE MEASUREMENT MODE

PB

.......

REC

Parentheses (

Wihout

......

I

)

Parentheses

I

2

I

3

I

99

4

I

5

I

6

I

AUDIO MODULE

I

WJNTK0677GEZZ)

(F3626GE)

+

OPERATION

DUNTK3627HE50

(F3627GE)

I

.-

H

I

^^._

-..

-

HEAD AMPLIFIER CIRCUIT

A

0

C

D

E

ROTARY TRANS

F

L E-A

G

VIDEO HEAD

RHEDVOO

R 1-A

I7GEZZ

H

1

*

VOLTAGE MEASUREMENT MODE

PB

. _ . . . .

REC . . . . . .

Parentheses (

W&hoi& Parentheses

I

1

2

I

3

I

4

I

5

I

6

I

103

Sharp 14VT10X1 Schematic

Specifications and Main Features

Frequently Asked Questions

User Manual