Sharp VC-90ET Bedienungsanleitung

VC-90ET

SHARP

SERVICE

MANUAL

VIDEO

CASSETTE

RECORDER

move.

VC-90ET

the

interests

user-safety

(Required

safety

regulations

some

countries)

the

set

should

restored

its

original

condition

and

only

parts

identical

those

specified

should

used.

CONTENTS

SPECIFICATIONS.

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seers

DISASSEMBLY

AND

REASSEMBLY...........ccssesscsscsecsscrececeeneesneeseeserseeseserscsvenseeseneeesenenaes

FUNCTION

MAJOR

MECHANICAL

ADJUSTMENT,

REPLACEMENT

AND

ASSEMBLY

MECHANICAL

UNITS

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ses

ADJUSTMENT

ELECTRICAL

CIRCUITRY

........ecsccsscessetscesceseceessessessscsncneseseceeseeeersteesseseeeseseqaaseenecseesscersssenenocecensasenaerees

TROUBLESHOOTING

GUIDE

BLOCK

DIAGRAM

WAVE

FORMS

..........sccsccccecsereesssessesnseceeseeasensssennecenssnscenecesnsceeseosecensosessassesaaraeesssnenereenans

SCHEMATIC

DIAGRAMS

WIRING

SIDE

PWBS

...........ccecccsceressecsssseesscsecssecnsenesenaeseeceanenserssceasnsesersnecausansaaceesseenaee

REPLACEMENT

ELECTRICAL

PARTS

LIST

uu...

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EXPLODED

VIEWS.

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PACKING

THE

SET

PPPPTPSTITITTITirrrrrrrrrrrietee

rier

PPPTITTTISTTITITITTTT

TTT)

SS SS

SHARP

CORPORATION

VC-90ET

Format:

Video

recording

system:

Video

signal:

Recording

playing

time:

Tape

width:

Tape

speed:

Antenna:

Receiving

channel:

converter

output

signal:

Power

requirement:

Power

consumption:

Operating

temperture:

Storage

temperature:

Weight:

Dimensions:

VIDEO

Input:

Output:

AUDIO

Input:

Output:

Accessories

included:

Note:

SPECIFICATIONS

VHS

PAL,

SECAM

MESECAM,

NTSC

standard

Rotary,

slant

azimuth

two

head

helical

scan

system

PAL,

SECAM,

NTSC

colour

monochrome

(CCIR

System

B/G,

D/K,

signal

240

min

max.

with

SHARP

E-240

tape

(PAUMESECAM/SECAM

mode)

hours

max.

with

SHARP

E-240

tape

(PAL/MESECAM/SECAM

mode)

160

min

max.

with

SHARP

T-160

tape

(NTSC

mode)

hours

max.

with

SHARP

T-

160

tape

(NTSC

mode)

12.7mm

23.39

mm/sec.

(PAL

mode)

33.35mm/msec.

(NTSC

mode)

11.7

mm/sec.

(PALin

mode)

16.68mm/msec.

(NTSC

mode)

(PB

only)

11.12

mm/sec.

(NTSC

mode)

ohm

unbalanced

VHF

E2~E

12,

(44.25MHz~295.25MHz)

UHF

E21~E69,

(471.25MHz~885.25MHz)

UHF

Channel

E30~E39

(adjustable).

Preset

Channel

E36

AC110~240V,

AUTO

50/60

Approx.

24W

(at

AC220V

50Hz)

5°C

40°C

20°C

55°C

5.5kg

430

(W)

348

(D)

(H)

0.5~2.0

Vp-p,

ohm

1.0

Vp-p,

ohm

Line:

dB,

than

47k

ohm

(with

4dB/-

8dB

ATT.

)

Line:

dB,

less

than

ohm

Antenna

ohm

coaxial

connector

cable

(plug

provided)

Operation

Manual

SHUTTLE

remote

contro!

Dry

Battery

Cable

part

our

policy

continuous

improvement,

reserve

the

right

alter

design

and

specifications

without

notice.

The

antenna

must

correspond

the

new

standard

DIN

45325

(IEC

169-2)

for

combined

UHF/VHF

antenna

with

ohm

connector.

VC-S0ET

DISASSEMBLY

AND

REASSEMBLY

Remove

the

four

upper

cabinet

fastening

screws

Remove

the

eight

bottom

panel

fastening

screws

Remove

the

one

front

panel

fastening

screw

©.

Release

the

three

clips

and

remove

the

front

panel.

Remove

the

HiFi

PWB

holder

©.

Remove

the

one

SYSCON

SERVO

PWB

Holder

fastening

screw

©.

Remove

the

one

SUB

CHROMA

PWE

Holder

fastening

screw

10.

11.

12.

13.

Remove

the

one

Converter

Holder

fastening

screw

@).

Remove

the

two

antenna

terminal

cover

fastening

screws

Remove

the

two

main

PWB

fastening

screws

Remove

the

two

head

amp

PWB

fastening

screws

(1)

Remove

the

two

power

unit

fastening

screws

(2,

Remove

the

four

mechanism

chassis

fastening

screws

(13).

Release

the

timer

PWB

fastening

clips.

Release

the

operation

PWB

fastening

clips.

Full

erase

head

ass'y

Kis

Supply

pole

base

ass'y(2)

V¥C-90ET

FUNCTION

MAJOR

MECHANICAL

PARTS

(TOP

VIEW)

Take-up

pole

base

ass’y

21)

Drum

ass'y

Tension

arm

assy

(3)

Brake

shifter

(4)

Back

tension

lever

(5)

Supply

reel

disk

(6)

Main

supply

brake

lever

Full

erase

head

ass’y

;

Erase

the

whole

records

the

tape

the

recording

mode.

Tension

arm

ass'y

Detects

the

tension

tape

while

running,

and

brakes

the

supply

reel

disk

via

the

tension

bane.

Brake

shifter

Set

the

position

brake

the

accordance

with

the

modes

such

stop

and

playback.

Back

tension

lever.

Back

tension

lever

Bakes

the

supply

reel

disk

certain

degree

prevent

tape

slackening

during

“loading”

and

“shifting

from

playback

video

rewind”.

Main

supply

brake

Brakes

the

supply

reel

disk

prevent

tape

slackening

when

the

unit

stopped

fast

forward

rewind

mode.

Main

take-up

brake

Brakes

the

take-up

reel

disk

prevent

tape

slackening

when

the

unit

stopped

fast

forward

rewind

mode.

Half-loading

level

Bring

the

tape

contact

with

the

A/C

head,

putting

half-loading

state

the

fast

forward

orrewind

mode.

Video

brake

lever

contact

with

the

take-up

reel disk

normally,

and

brakes

certain

degree.

applies

larger

brake

the

video

rewind

mode.

24)

V.H

Cleaner

arm

ass’y

20)

A/C

head

ass'y

(19)

Cam

switch

(25)

Solenoid

ass’y

(23)

Dew

sensor

fo]

(18)

motor

Nate,

A|_—(16)

Pinch

roller

lever

ass'y

(5)

Relay

shifter

lever

eYay

;

(14)

Capstan

D.D.motor

©)

(13)

Reverse

guide

(12)

Take-up

reel

disk

Sal

(GO)

(11)

Video

brake

lever

(10)

Half-loading

lever

(9)

Main

take-up

brake

lever

(8)

Idler

gear

ass‘y

Reverse

guide

Pulls

out

the

tape

the

video

rewind

mode,

and

controls

the

tape

drive

train

height

with

the

upper

and

lower

guides.

Relay

shifter

lever

Transmits

the

operation

the

master

cam

the

brake

shifter,

and

operates

the

reverse

guide.

Pinch

roller

lever

ass’y

Press-fits

the

tape

the

capstan

during

tape

running.

The

right

protrusion

switches

the

clutch

the

cassette

housing

control

assembly

“

tape

eject”,

and

makes

the

mechanism

eject

the

tape.

Master

cam

Turns

clockwise

during

loading,

and

counterclockwise

during

unloading,

and

moves

the

shifter

the

accordance

with each

mode.

motor

motive

power

which

drives

the

mechanism.

transmits

the

power

the

master

cam

and

cassette

housing

control

assembly

via

the

belt.

Cam

switch

Rotates

synchronously

with

the

master

cam,

and

detects

the

position

each

mode

means

the

internal

switch.

Dew

sensor

Detects

the

generation

dew

the

set.

stops

the

mechanical

action

the

set

when

finding

any

dew

the

set.

VC-SOET

FUNCTION

MAJOR

MECHANICAL

PARTS

(BOTTOM

VIEW)

Relay

gear

drive

lever

Reel

sensor

(9)

Take-up

gear

(10)

Supply

gear

(8)

Auxiliary

fast

forward

brake

lever

Brake

solenoid

(5)

(6)

Reel

pulley

Slow

brake

Gets

contact

with

the

capstan

D.D.

motor

linking

the

master

cam

the

slow

still

mode,

and

brakes

certain

degree.

Capstan

D.D.

motor

motive

power

which

runs

the

tape.

transmits

the

power

via

the

reel

belt.

Reel

belt

Transmits

the

power

run

the

tape

the

reel

Brake

solenoid

Adsorbs

and

holds

the

brake

shifter

the

fast

forward

and

rewind

modes,

and

releases

the

Reel

pulley

Transmits

the

power

the

capstan

D.D.

motor

the

reel

disk

via

the

reel

idler.

Reel

sensor

element

which

sheds

the

light

onto

the

reflection

plate

affixed

the

bottom

side

the

reel

disk,

and

detects

the

rotation

the

reel

disk

through

receiving

the

reflected

light.

Auxiliary

fast

forward

brake

lever

Brakes

the

supply

reel

disk

certain

degree

the

fast

forward

and

rewind

modes.

Take-up

gear

Shifts

the

take-up

pole

base

and

guide

roller

via

the

relay

gear,

and

applies

the

tape

around

the

durm

assembly,

well

transmits

the

power

the

supply

gear.

Supply

gear

Shifts

the

supply

pole

base

and

guide

roller

via

the

take-up

gear,

and

applies

the

tape

around

the

drum

assembly.

Relay

gear

drive

lever

Transmits

the

movement

the

master

cam

the

take-up

gear

via

the

relay

gear.

VC-90ET

ADJUSTMENT,

REPLACEMENT

AND

ASSEMBLY

MECHANICAL

UNITS

Here

will

describe

relatively

simple

service

work

the

field,

not

referring

the

complicated

repairs

which

would

require

the

use

are

sure

that

the

easy-to-handle

tools

listed

below

would

than

handy

for

periodical

maintenance

keep

the

machine

its

original

special

equipment

and

tools

(drum

assembly

working

condition.

replacement,

for

example).

TOOLS

NECESSARY

FOR

ADJUSTING

THE

MECHANICAL

UNITS

The

following

tools

are

required

for

proper

service

and

satisfactory

repair.

Jig

Item

Reel Disk

Height

Adjustment

Jig

JiGRHO002

JiGMP0001

JiGACH-F18

JiGTGOO90

JiGTG1200

JiGTHOO06

JiGVHT-063

JiGSG2000

JiGHWO0009

JiGHWO0015

VROATFPS

Master

Plane

AIC

Head

Tilt

Adjustment

Jig

Torque

Gauge

(90g)

Torque

Gauge

(1.2

kg)

Gauge

Head

Cassette

Torque

Meter

Tension

Gauge

(300g)

Tension

Gauge

(2.0kg)

Hex

Wrench

(0.9mm)

Hex

Wrench

(1.2mm)

Hex

Wrench

(1.5mm)

Alignment

Tape

(NTSC)

Alignment

Tape

(PAL)

Hi-Fi

Alignment

Tape

(PAL)

Alignment

Tape

(SECAM)

HiFi

Alignment

Tape

(NTSC)

Code

Rep

Configuration

These

jigs

are

used

for

checking

and

adjusting

the

reel

disk

height

This

Jig

used

for

setting

the

A/C

head

tilt.

These

jigs

are

used

for

checking

and

adjusting

the

torque

take-up

and

supply

reel

disks.

This

cassette

torque

meter

used

for

checking

and

adjusting

the

torque

take-up

for

measuring

tape

back

tension.

There

are

two

Gauges

used

for

the

tension

measurements,

300

and

2.0

kg.

These

Jigs

are

used

for

loosening

tightening

special

hexagon

type

screws.

These

Tapes

are

especially

used

for

electrical

fine

adjustment.

VC-90ET

Jig

Item

Configuration

JiGDT-0001

Tension

Gauge

Adapter

JiGADP003

Special

Bladed

Screwdriver

jens

Tension

Band

and

Plate

;

Adjustment

Jig

JiGDRiVER-6

This

used

for

replacement

the

Drum

Replacing

Jig

VCR's

upper

drum.

This

Jig

used

with

the

tension

gauge.

Rotary

Transformer

Clearance

Adjusting

Jig.

This

Screwdriver

used

for

adjusting

the

guide

roller

height.

This

Jig

used

for

adjusting

the

tension

band

and

tension

plate.

This

used

screw

down

resin-

made

parts:

the

specified

torque

5kg.

Torque

Driver

(5kq)

JiGTD1200

JiGDRIVER1

10-7

Box

Driver

JiGDRIVER110-4

Retaining

Guide

Height

JiGGH-F18

Adjustment

Jig

jewore

NOTE:

Current

JiGMA0001

contains

Master

Plane

(JiGMP0001)

and

Disk

Height

Adjusting

Jig

(JiGRHO001).

Even

though

new

Disk

Height

Adjusting

Jig

GiGRH0002)

covers

greater

height,

this

new

Jig

(JiGRH0002)

can

used

for

current

JiGRH0001,

but

current

Jig

JiGRH0001)

cannot

used

JiGRH0002.

Master

Plane

(JiGMP0001)

can

used

with

JiGRH0001

and

JiGRH0002

well.

This

Jig

used

for

height

adjustment

the

AVC

head.

This

Jig

used

for

height

adjustment

the

retaining

guide

and

X-position.

This

Jig

used

for

height

adjustment

the

retaining

guide.

This

Jig

used

for

height

Retaining

Guide

Height

adjustment

the

reverse

guide.

Adjustment

Jig

VC-90ET

MECHANICAL

PARTS

REQUIRING

PERIODICAL

INSPECTION

Use

the

following

table

guide

maintain

the

mechanical

parts

good

operating

condition.

Maintained

500

1000

Guide

roller

ass‘y

Abnormal

rotation

significant

vibration

requires

replacement.

Clean

with pure

high

quality

isopropyl

alcohol.

Supply

impedance

roller

ateral

noises

Head

occasionally

blocked

Supply

impedance

roller

(inner)

Supply

impedance

roller

flange

Retaining

guide

Slant

pole

Clean

tape

contact

area

with

the

specified

cleaning

liquid.

Video

head

Poor

color,

beating

Sound

too

small

distorted

tape

running,

uneven

color

tape

running,

tape

slack

tape

running,

tape

slack,

fast

forward/rewind

Full-erase

head

Clean

tape

contact

area

with

the

specified

cleaning

liquid.

A/C

head

Capstan

D.D.

Motor

fem

Poor

S/N

ratio,

eee

Pinch

roller

Clean

rubber

and

rubber

contact

area

with

the

specified

cleaning

liquid.

Reel

belt

Cassette

not

loaded

unloaded

belt/Cassette

belt

Tension

band

ass'y

Cassette

not

loaded

unloaded

motor

Replace

the

roller

the

cleaner

when

wears

down.

Just

change

the

video

head

cleaner

arm

assembly

AHC

(Automatic

Head

Cleaner)

for

new

one.

ial

below

[04

Reel

block*

*See

the

table

below

for

servicing

the

reel

block

parts.

Supply/Take-up

reel

disks

tape

running,

ean

with

pure

hig

;

tape

Sack

auallty

isopt

opyl

Main

supply/take-up

brake

levers

Tape

slack

Video

brake

lever

Idler

gear

ass'y

tape

running

Reel

Pulley

Saas

NOTE:

Partreplacement.

Cleaning

(For

cleaning,

use

lint-free

cloth

dampened

with

pure

isopropyl!

alcohol).

Oilrefilling

(The

indicated

point

should

lubricated

with

high

quality

spindle

oil

every

1000

hrs).

This

model

has

adjusting

parts

for

torques,

tensions,

etc.

the

reading

outside

the

specified

range,

cleanor

replace

the

part.

REMOVAL

AND

REASSEMBLY

CASSETTE

HOUSING

CONTROL

ASSEMBLY

Supply

reel

disk

Removal

Set

the

cassette

ejected

condition

the

cassette

eject

mode.

Unplug

the

recorder

from

the

main

source.

the

procedures

below

the

specified

order.

Remove

the

cassette

belt

©.

Disconnect

the

FFC

(Full

Flat

Cable)

©)

Remove

the

cassette

housing

installation

screws

@).

Slide

and

pull

out

the

cassette

housing

control

assembly

upward

Cassette

housing

installation

screw

(Full

Flat

Cable)

belt

When

the

belt

detached,

tuck

the

figure

that

it is

kept

free

from

grease.

the tab

the

hole.

Cassette

housing

(1)

Cassette

When

reassembling,

insert

VC-SOET

Place

the

unit

the

eject

mode

removal

reassembly

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

mechanism

and

the

cassette

controller

are

accurately

adjusted

after

ejection.)

MECHANICAL

OPERATION

CHECK

WITHOUT

CASSETTE

When

power

on,

the

general

operations

the

mechanism

can

checked

without

cassette.

Note

the

following

points.

Check

video

rewind

and

rewind,

rotating

the

take-up

reel

disk

hand

(in

either

normal

reverse

direction).

not

rotated,

the

reel

sensor

works

shift

the

mechanism

the

eject

mode.

When

the

stop

button

pressed,

the

mechanism

does

not

stop

normal

stop

position.

shifts

the

eject

mode

and

stops.

When

the

stop

button

pressed

the

playback,

video

rewind,

and

video

forward

modes,

the

supply

reel

disk

keeps

rotating

for

several

seconds

for

elimination

tape

slack

the

course

shifting

the

eject

mode.

such

case,

rotate

the

take-up

reel

disk

somewhat

hand,

and

the

supply

reel disk

stops,

which

can

reduce

the

working

time.

REPLACEMENT

WORM

WHEEL

ASSEMBLY

Figure

1-1.

frame

(L)

Reassembly

Before

installation

the

cassette

housing

control

assembly,

place

the

unit

the

stop

mode

with

the

power

on,

then

unplug

the

power

cord.

(The

main

body

placed

the

eject

mode.)

the

procedures

for

removal

the

reverse

order.

Notes:

sure

unplug

the

power

cord

removal

and

reassembly.

Keep

the

cassette

belt

free

from

grease.

case

its

adhesion,

clean

the

belt.

using

magnet

screw

driver,

sure

keep

away

from

the

A/C

head,

(Full

Erase)

head,

the

drum.

removal

and

reassembly,

take

care

not

hit

the

cassette

housing

control

assembly

tools

against

the

guide

pin,

drum,

the

thereabout.

Start

sensor

PWB

Cassette

switch

connector

Worm

bracket

tight

screw

Phase

‘Worm

wheel

ass'y

Cassette

housing

frame

(R)

gear

Figure

1-2.

VC-90ET

Removal

Unsolder

the

cassette

switch

connectors

from

the

start

sensor

PWB.

Start

sensor

PWB

Start

sensor

PWB

fixing

hook

Cassete

switch

Soldering

connector

Figure

1-3.

Lift

the

start

sensor

PWB

pressing

the

two

start

sensor

PWB

fixing

hooks

inward.

—_>

Lift

hanes

sensor

PWB

Start

sensor

PWB

fixing

hook

Figure

1-4.

Unscrew

one

tight

screw

detach

the

worm

bracket.

Note:

The

worm

shaft

bearing

can

easily

come

out

position.

careful

not

lose

it.

Worm

shaft

bearing

Worm

bracket

worm

wheel

assy

Figure

1-5.

Remove

the

worm

shaft

assembly,

pulley,

and

cassette

belt

all

from

the

cassette

housing

frame

(R).

Cassette

belt

Pulley

Cassette

housing

frame

(R)

Phase

gear

Worm

wheel

ass'y

Figure

1-6.

Tally

mark

Place

the

slider

just

above

the

worm

wheel

assembly

(Figure

1-7).

(The

retainer

the

slider

locked

two

positions

hen.

unlock

the

Figure

1-8.)

Pull

out

the

worm

wheel

assembly

toward

you

pressing

the

switch

lever

upward.

(Figure

1-7)

Slider

lever

Worm

wheel

ass‘y

\—Phase

gear

Cut

washer

Figure

1-7.

Retainer

opening

{Also

provided

the

(L)}

side

cassette

housing

frame)

Cassette

housing

frame

{R)

Slider

Retainer

Press.

Cassette

housing

frame

(R)

{L)

side

Figure

1-8.

Reassembly

Turn

the

phase

gear

clockwise

until

the

slider

comes

halt

the

cassette

insertion

direction.

(See

the

Figure

1-9.)

Insert

the

set

worm

wheel

gear

assembly

into

the

cassette

housing

frame

(R),

matching

the

mark

the

phase

gear

with

the

mark

the

worm

wheel

gear.

Detach

the

cut

washer

the

phase

gear

assembly

and

the

phase

gear

for

easier

installation

worm

wheel

assembly.

Note:

Make

sure

that

the

slider

the

groove

the

drive

gear

arm.

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