Sharp 14VT10X1 Schematic

SHARP

SERVICE MANUAL

S81G314VT10X1

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

DISASSEMBLY AND REASSEMBLY

FUNCTION OF MAJOR MECHANICAL PARTS

ADJUSTMENT, REPLACEMENTANDASSEMBLY OF MECHANICAL UNITS

ADJUSTMENT OF THE ELECTRICAL CIRCUITRY

TROUBLESHOOTINGGUIDE

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

SIGNAL FLOW SYMBOLS AT A GLANCE

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

OVERALLDIAGRAM

SCHEMATICDIAGRAMS

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

REPLACEMENT ELECTRICAL PARTS LIST

EXPLODEDVIEWS

PACKINGOFTHESET

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70x1

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141

SHARP

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

Remove the three VCR’s power unit fastening

screws @. Remove the six VCR fastening screws 0 and

remove the VCR with the VCR’s operation.

Remove the CRT’s second anode cap @ from

the CRT.

Remove the “L2” lead wire @ from the CRT

socket unit

Remove the

Remove the TV mother unit with the frame

from the front cabinet.

@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

16.

Remove the four CRT fastening screws

DISASSEMBLY AND REASSEMBLY OF THE VCR SECTION

1. Remove the eight VCR holder fastening screws

2. Remove the four upper cabinet fastening screws

3. Remove the seven bottom plate fastening screws

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

Loadi

motor

Full erase head ass’y

Supply pole base

Tension arm ass’

No.

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

Tension arm ass’y

Detects the tension of tape while running, and brakes

the supply reel disk via the tension band.

Brake shifter

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

the modes such as stop and playback.

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”.

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

when the unit is stopped in fast forward or rewind

mode.

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

(14) Caostan

Function

tape.

Relay

shifter lever

D.D.motor

rer

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

@Take-up

loading gear

Supply loading gear

-4

AuxiliaFy

brake lever

fast forward

Brake solenoid 5

powerto

Function

run the tape to the reel pulley.

IlO.

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

A motive power which runs the tape. It transmits the

power via the reel belt.

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.

Reel pulley

Transmits the power of the capstan

reel disk via the reel idler.

degree.

D.D.

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

6 Reel pulley

No.

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

’

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.

Head Tilt Adjusting Jig

Jig Item Configuration

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

of take-up and

A/C

Gauge Head

Cassette Torque Meter

Tension Gauge (3009)

Tens&

Gauge (2.0kg)

Hex Wrench (0.9mm) JiGHW0009 AE

Hex Wrench (1.2mm)

Hex Wrench (1.5mm) JiGHWOO15 AE

Alignment Tape (PAL) VROCPSV CD

Alignment Tape (NTSC) VROATSV CD

Drum Replacing Jig

JiGTH0006

JiGVHT-063 C2

JiGSG0300

JiGSG2000

JiGHWOO12 AE

JiGDT-0001

This cassette torque meter is used

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.

rension Gauge Adapter

jpecial

Jig Item

Bladed Screwdriver

Part No.

JiGADP003

JiGDRiVERH-4

C-:odc

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

9djusting

Torque Driver

Box Driver

Retaining Guide Height

Adjusting Jig

Reverse Guide Height

Adjusting Jig

Jig

JiGDRiVER-

JiGTDl200

JiGDRiVER 10-7

JiGDRiVER 10-4

JiGGH-F18

JiGRVGH-F18

;“.:;

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-

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

Part replacement.

cl:

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

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

1000

hrs).

0 n

0 0

on no on

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.

R,EMOVAL AND REASSEMBLY OF

CASSETTE HOUSING CONTROL ASSEMBLY

Removal

Set the cassette ejected condition in the cassette eject mode.

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

d) Slide and pull out the cassette housing control

assembly

upward @I.

~-I-

/==h

- _Q3

Cassette housing

setscrew

Place the unit in the eject mode in removal or

5. reassembly of the cassette housing control assembly.

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

@ 0

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

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

IVI c IY I

(R)

Figure

u r

l-2.

vv u n WI

VvnrcL

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

Retainer

IL)

side

--Id

Press.

Cassette housing frame

(R) (Ll

side

Figure

1-8.

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

Drive gear arm

Figure

l-9.

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

shaft ass.“-. 1

Cassette loading belt

Clutch

Pullev

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

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

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:

tight

Inset-t 0

before screwing into 8 and

Worm bracket

Cassette housing frame

Figure

(R).

ssette housing frame

Switch lever

l-11.

(R)

(RI

boss

Drive oear

Drive gear arm

Drive spring

oea%

(RI

LDrive

(Drive gear bottom view)

gear arm

Drive gear

spring shaft

(RI

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

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

sensor PWB

Worm bracket

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

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

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

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.

REPLACEMENT OF LOCK RELEASE LEVER

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)

the slider assembly off the grooves of the

cassette housing frames.

Remove the lock release lever

from the slider

holder(R)

Reassembly

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

1-17

and l-18.)

I. _I

(R).

Slide the slider holder

(RI

downward so that the

two catches of the slider holder (R) fit the

opening of the slider.

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.

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

(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

here

Figure

Lock release lever

Lock release lever spring

l-18.

Wetght to prevent i,,

1500 gi

float

Note:

The weight should not be more than 500

Figure l-19.

.,T

. .

Mechanism

chassis

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).

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

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>.

1-20(b)).

enston ever

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

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

Take-up

reel

disk

Take-up reel ratamer

Figure

l-21.

Reassembly (Supply reel disk)

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

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

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

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

Notes

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.

Figure

l-20.

/ 0

L I-

rzl

.-c

Figure

1-22

Supply reel disk

Screw

Supply reel

T’

retamer

S‘;bply d!sk catch

ass’y

reel

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

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

Take care not to damage the video search brake

lever.

Clean the reel disk shaft well.

and apply

011

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

(b)).

Note

Whenever replacing the reel disk, perform the

height checking and adjustment.

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).

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

Slide It right and left.

and check contact the reel disk.

&yg_im’+ ‘> .2

Reel disk

wth

Reel disk

adlustIng 119

height

Mechanism chassis

Figure

(b)

Figure l-26

1-24.

CHECKING AND ADJUSTMENT OF TAKE-UP

TORQUE IN FAST FORWARD MODE

Remove the cassette housing control assembly.

Setting

CHECKING AND ADJUSTMENT

OFTAKE-UP

TORQUE IN REWIND MODE

Remove the cassette housing control assembly.

Setting

Torque gauge

Set the scale to

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

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.

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

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.

Adjustment

Figure

700gfm

The gauge is held its maximum value.

l-30.

or more

at-

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

may not

fly off.

2. When checking the take-up torque, do not keep the reel disk locked for a longer time.

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

Remove the cassette housing control assembly.

Load a cassette torque meter

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.

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.

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.

CHECKING THE FAST FORWARD BACK

CHECKING THE VIDEO SEARCH REWIND

TENSION BACK TENSION

Remove the cassette housing control assembly.

Checking

Remove the cassette housing control assembly.

Checking

‘I I\’

e :h’I

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

Remove the cassette housing control assembly.

Checking

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

Push the video search rewind

video search rewind mode.

Torque gauge

very slowly

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

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.

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

.aoo-

1,200

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.

Check that the reading of the tension gauge is in the range of 1000 to 1200

CHECKING AND ADJUSTMENT OF TENSION POLE POSITION

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.

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.

Center

SUPPlY

Tension band

and plate

sung

Supply impedance roller Tension pole

ensjon arm

utde roller A

Check the

Tenston band

and plate

adjusting 119 settlng

hole

lef-t

echanism chassts

Video

cassette tape

(E-1

80)

Guide roller

Tenston band adjustment bracket

Figure l-38.

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.

Supply Impedance roller

TensIon pole

adI1

(b)

Figure l-37.

Checking

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.

Tenston band adjusrment bracket

/ -

Figure

1-39.

Supply reel

band

CHECKING AND ADJUSTMENT OF RECORD

PLAYBACK BACK TENSION

Remove the cassette housing control assembly.

Open here

Cassette torque meter

Figure 142. Not used.

Push the record button to place the

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.

Adjustment

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

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

tension spring hook plate in the direction of A or

CHECKING THE BRAKE TORQUE

Checking the brake torque at the supply side

Torque

gauge

Tension spring

hook plate

Figure

1-41

Tenston spring

Tension swng

hook plate

Mechanism chassts

,-Supply reel disk

Adjust in

the center

Figure

-5:’

the Idler gear

143.

Supply reel

disk

--/

Remove the cassette housing control assembly.

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.

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.

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

@and

Adjust the Idler gear in the center.

Mechanism

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.

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.

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).

R&fCEMENT

Remove the cassette housing control assembly.

1. Place the unit in the unloading mode, and

unplug

Removal

Loosen the tilt adjusting screw

1. Remove the azimuth adjusting screw

2. Remove the AK head screw

3. Unsolder the A/C head

the power cord.

OF A/C (Audio/Control)

PWB

soldered to the

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.

head

PWB

Pay attention to the azimuth spring.

Figure

14.

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

Tilt adjusting

screw

A/C head height

Replacement

Figure 146.

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

:rew

driver

Figure

1-47.

(b)

Figure l-49.

[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

Figure l-51.

SdJurtlng

Jig

and the lower flange

guide.

(b)

A/C head-,

[Height adjustment of reverse

Reverse guide adjusting jig

height?

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.

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

&-;arher

*Wing

-Spring

@-washer (iron

w Cut

washer

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

Counterclockwise

Hexagon

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.

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)

(+)

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

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.

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.

Push the

envelope waveform from MAX to

(+)

(-)

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

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

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.

srde

gurde

directton

urde

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

that a flat response is obtained on the envelope waveform.

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

same time to the preset mode.

Rotate the X-position adjusting nut with an

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

low side envelope.

Adjust the playback switching point.

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.

chassis

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

Remove the cassette housing control assembly.

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

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

D.D.

motor and check the

movement.

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.

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-

Removal (Follow the order of indicated

numbers.)

Remove the

Remove Ihe reel belt

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

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

Remove the E ring

Rotate the take-up loading gear, take-up

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

Remove the relay gear drive lever

Reassembly

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.

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

Removal

leads

Remove the

3. Unscrew the three screws

4. Pull the loading

cassette loading

block upward.

belt

Figure l-68.

3. Finally connect the leads and apply the cassette loading belt.

Notes:

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

Unsolder here

Label

Loadmg

block

Figure l-69.

Unsolder the leads 0 from the lpading motor.

2. Unlock the

left

and right catches

of the cam

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

Tally marks

,-Loading

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

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

Removal

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

@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

Reassembly

Remove the loading motor, and mount a new

baLk

end of the

motor and

nut the

or the

motor

Figure

l-71.

Loadq heir

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

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.

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

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.

Replacement (Follow the order of the indicated

numbers.)

Unsolder the leads.

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.

Reassembly

Notes :

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

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.

Removal (Reverse the order in reassembly.) Remove the

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

FFC 0.

D.D.

MOTOR

Pull out the

3. Remove the three D. D.

5. Remove the D.D.

Notes

When removing the

stator

assembly, use care not to hit the loading

D.D.

rotor

stator

@,.

stator

setscrews

assembly

D.D.

rotor assembly or

relay gear.

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.

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

Head Model]

Figure l-76.

Set the new drum.

Fasten the upper drum in place with the two

screws.

Solder the leads.

Note: Soldering should be performed quickly

and carefully without touching adjacent

patterns.

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

+ 108 hidden pages

Sharp 14VT10X1 Schematic

Specifications and Main Features

Frequently Asked Questions

User Manual