Panasonic PT-302 Manuel utilisateur

ORDER

NO.

VED86100027C3

ervice

Manual

Colour

Video

Projector

PT-302

chassis

No.

Q5

The

service

technician

is

required

to

read

and

follow

the

‘‘Safety

Precautions’

and

’’Important

Safety

Notice”

in

this

service

manual.

Specifications

Power

Source:

AC

220V

~

240V,

50/60

Hz

4318

mm

(170

inch)

Picture

size:

Power

Consumption:

179W

(average)

5102

mm

(200

7/8

inch)

Projection

T

ube:

7

inches

(179

mm)

specially

developed

5080

mm

(200

inch)

Picture

size:

High-Brightness

liquid

cooled

5963

mm

(234

3/4

inch)

CRTs

(R,

G,

B).

6350

mm

(250

inch)

Picture

size:

Lenses:

Double

Focus,

Three

F

1.0

145

7400

mm

(291

11/32

inch)

Lenses

(HYBRID)

7620

mm

(300

inch)

Picture

size:

Resolution:

Video......

650

TV

Lines

(typical)

8835

mm

(345

27/32

inch)

RGB........

1000

TV

Lines

(typical)

Light

Flux:

500

lumens

(typical)

at

white

peak

Video

Input

Level:

140.3Vp-p

75Q

Operating

Ambient

Line

in/out

Level:

1+0,3Vp-p

75Q

or

high

impedance

Temperature:

32°F

~

104°F

(0°C

~

+40°C)

RGB

Input

Level

R:

0.74+0.3Vp-p

752

Operating

Ambient

G:

0.7+0.3Vp-p

75Q

Humidity:

20%

~

80%

(GSYNC:

140.3Vp-p

75Q)

Supplied

Accessories:

AC

Cord

(3

types)

B:

0.7+0.3Vp-p

75

Mounting

kit

(1

set)

H/HV:

0.3

~

6V,

high

impedance

Dimensions:

Height:

290

mm

(11

13/32

inch)

V:

0.3

~

6V,

high

impedance

Width:

576mm

(22

11/16

inch}

Screen

Size:

3810

~

7620

mm

(150

~

300

inch)

Depth:

606

mm

(23

29/32

inch)

Throw

Distance:

3810

mm

(150

inch)

Picture

size:

Weight:

77

\|bs.

(35

kg)

4528

mm

(178

1/4

inch)

;

Specifications

are

subject

to

change

without

notice.

Weight

and

dimensions

shown

are

approximate.

a

rs Fy

5

Panasonic

Matsushita

Elecite

Weds

Co.

PT-302

CONTENTS

FEATURES

oc.

o's Sys ase

8

ad

Reece

che

erarae

Beddacs

ar

ahaa

Ay.

eee

a

eee

RO

oes

ee

A

2

SAFETY

PRECAUTIONS

225.25

iecce

Sie

5

ata

ela

alee

le

esti

ee

tee

as

Wwe

Gee

a

Ste

9

She

3

LOCATION

OF

CONTROLS,

OPERATIONS

AND

CONNECTION

OPTIONAL

EQUIPMENT...........

0.00

cue

ue

c

ences

4~8

DISASSEMBLY

INSTRUCTIONS

...........

00.

ccc

cere

eee

ne

eres

9,10

MAIN

PARTS

LOCATION

CHART

..........

0...

cc

cece

ee

tee

ere

eens

11

CAUTIONS

FOR

SERVICING

.........

0...

ccc

ee

eee

eens

12,13

FIELD

ADJUSTMENTS.

.....

2...

..

eee

e

ee

eee

ane

14

~20

INSTALLATION/ADJUSTMENT

PROCEDURE

..............0

000

ec

ucuae

21

~

32

LOCATION

OF

TEST

POINT

AND

CONTROLS

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

00

veer

e

eee eee

33

~

35

BLOCK

DIAGRAM).

6.5.4.0

6-06

eee

g

ow

be

Ses

COS

Se

EO

Hews

Gee

Rae

36

~

38

INTERCONNECTION...

0...

cc

cee

eee

ee

eee

ee

eee

39,

40

TERMINAL

GUIDE

OF

IC’S,

TRANSISTOR

AND

DIODES.

..............0

0000

ae

41

CIRCUIT:

BOARD

i

oie:

oa

hia

ish

ae.

hb

Gee

ie

ee

SPR

ew

le

Ge

Oe

bala

wee

42

~

54

SCHEMATIC

DIAGRAM

.........

0.0.

ecw

ee

eee

anaes

55

~

74

F/K/P/Q/V/X-BOARD

Sections.

.........

0.00

cece

eee

ee

eee

ee

ees

57,

58

M-BOARD

Section

.......

0.0...

ce

eee

ewe

eee

ee

eee

eens

59,

60

B/S/LR/LG/LB-BOARD

Sections...

..........

00

cc

eee

uceceucuveees

65

~

68

C/J/TR1/TR2-BOARD

Sections...

2.2...

0.0...

cece

ee

eee

ee

69

~

71

A/G/R/T-BOARD

Sections...

0.0...

0...

cece

ee

et

eee

72

~74

EXPLODED:

VIEWS

en.

5:

ees

cece

ese

el

a

ote

eae

eee.

AS.

rete

bl

ce

75

~

80

TROUBLESHOOTING.

....

0.0...

cece

ccc

eee

te

eee

81,

82

REPLACEMENT

PARTS

LIST...

0...

..

eee

ee

eee

ees

83

~

110

FEATURES

1

Superb

bright

picture:

High

luminance

output:

5

Improved

raster

quality:

500

lumens

(typical)

at

white

peak

High

voltage

regulation

characteristic:

0.3

MQ

2

Superb

resolution:

1000

Lines

(RGB)

(typical)

6

eee

installation

and

front/rear

projection

easily

selectable.

650

Lines

(Video)

(typical)

RGB

character

reproduction:

e

Ceiling

mount/front

projection

e

Ceiling

mount/rear

projection

equivalent

to

2000

characters

e

Floor

placement/front

projection

(80

x

25)

e

Ceiling

mount

rear

projection

with

mirror

3

Compact

size

and

light

weight

(35

kg,

77

Ibs),

for

easy

¢

Floor

placement

rear

projection

with

mirror

7

Wide-range

computer

compatibility

placement/installation.

aor

. : . :

8

Four

broadcast

system

capabilit

4

Compatibility

with

various

signal

input

sources:

sys

Spe

arty

PAL,

SECAM,

NTSC

and

M-NTSC

4.43

VTR/VCR

Video

Disk

Video

Camera

RGB

Computer

TV

Tuner

SAFETY

PRECAUTIONS

GENERAL

GUIDELINES

1.

It

is

advisable

to

use

an

isolation

transformer

in

the

AC

line

supply

before

servicing

this

model.

2.

When

servicing

observe

the

original

lead

dress,

especially

in

the

high

voltage

circuit.

In

case

of

a

short

circuit,

replace

every

part

which

has

overheated.

3.

After

servicing

observe

that

all

protective

devices

such

as

insulation

barriers,

fish

paper,

shields,

isolation

networks

and

fuses

are

properly

installed.

4.

Before

turning

the

receiver

on,

the

resistance

between

the

B+

line

and

chassis

ground

should

be

checked.

Connect

the

©

side

of

an

ohmmeter

to

the

B+

line

and

the

@

side

to

chassis

ground.

Each

line

should

have

more

resistance

than

specified,

as

follows:

B+

(B—)

Line

Minimum

Resistance

206V

10kQ

116V

3kQ.

27V

30022

17V

2002

12V

10022

10V

3Q

*

-17V

150Q

*

—

Side

to

ground

5.

If

the

set

is

not

intended

to

be

used

for

a

long

time,

the

power

cord

should

be

unplugged

from

the

AC

line

outlet.

6.

Potentials,

as

high

as

32.5

kV

are

present

when

this

set

is

in

operation.

Removal

of

the

covers

involves

the

danger

of

a

shock

hazard

from

the

set’s

power

supply.

Servicing

should

not

be

attempted

by

anyone

who

is

not

thoroughly

familiar

with

the

precautions

necessary

when

working

on

high-voltage

equipment.

Always

discharge

the

anode

of

the

projection

tube

to

the

set

chassis

before

handling

the

tube.

7.

After

servicing,

make

the

following

leakage

current

checks

to

prevent

a

shock

hazard.

LEAKAGE

CURRENT

COLD

CHECK

1.

Unplug

the

AC

cord

and

connect

a

jumper

between

the

two

plug

prongs.

2.

Turn

on

the

set.

3.

Measure

the

resistance

value

with

an

ohmmeter

between

the

jumpered

AC

plug

and

each

exposed

metallic

part

such

as

screwheads,

input

terminals,

control

shafts,

etc.

When

the

exposed

metallic

part

has

a

return

path

to

the

chassis,

the

reading

should

be

between

490

k{2

and

9

M&2.

When

the

exposed

metal

does

not

have

a

return

path

to

the

chassis,

the

reading

must

be

infinite.

—_

PT-302

LEAKAGE

CURRENT

HOT

CHECK

(See

Fig.

1)

I

Plug

the

AC

cord

directly

into

the

AC

outlet.

Do

not

use

an

isolation

transformer

for

this

check.

.

Connect

a

2

kQ,

10W

resistor,

in

series

with

an

exposed

metallic

part

on

the

receiver

and

an

earth

such

as

a

water

pipe.

.

Use

an

AC

voltmeter,

with

1000

ohms/volt

or

more

sensitivity,

to

measure

the

potential

across

the

resistor.

.

Check

each

exposed’

metallic

part,

and

measure

the

voltage

at

each

point.

.

Reverse

the

AC

plug

in

the

AC

outlet

and

repeat

each

of

the

above

measurements.

.

The

potential

at

any

point

should

not

exceed

1.4

volts

RMS.

_

In

case

a

measurement

is

outside

of

the

limits

specified,

there

is

a

possibility

of

a

shock

hazard,

and

the

receiver

should

be

repaired

and

rechecked

before

it is

returned

to

the

customer.

HOT-

CHECK

CIRCUIT

AC

VOLTMETER

(High

Impedance)

TO

WATER

PIPE

INSTRUMENT

’S

2kn,

LOW

J

(EARTH)

EXPOSED

METALLIC

PARTS

Fig.

1

X-RADIATION

WARNING:

|

The

potential

source

of

X-Radiation

in

the

color

Projection

System

is

the

High

Voltage

section

and

the

projection

tubes.

NOTE:

it

is

important

to

use

an

accurate,

peliodically,

calibrated

high

voltage

meter.

1.

Turn

the

Brightness

control

fully

counterclockwise.

.

Measure

the

High

Voltage.

The

high

voltage

meter

should

indicate

32

kV

+

0.5

kV.

If

the

upper

meter

indication

is

out

of

tolerance,

immediate

sevice

and

correction

is

required

to

prevent

the

possbility

of

premature

component

failure.

(Refer

to

hich

voltage

adjustment

in

the

manual.)

.

TO

prevent

an

X-Radiation

possibility,

it

ig

esen

tial

to

use

the

specified

projection

tube

only.

.

To

prevent

exposure

to

X-Radiation,

the

groy

ection

tube

shield

must

be

kept

in

place

with

power

ap

lied

to

the

set.

WARNING:

When

using

a

projection

tube

tet

jig

for

service,

ensure

that

jig

is

capable

otha

Nndling

32.5

kV

without

causing

X-Radiati«n.

PT-302

LOCATION

OF

CONTROLS,

OPERATION

AND

CONNECTING

OPTIONAL

EQUIPMENT

LOCATION

OF

CONTROLS

AC

IN

MAIN

POWER

SWITCH

IMPEDANCE

SELECTOR

SWITCH

LINE

IN/OUT

TERMINAL

VIDEO

INPUT

TERMINAL

G/EXT

SYNC

SELECTOR

SWITCH

V

INPUT

TERMINAL

H/HV

INPUT

TERMINAL

B

INPUT

TERMINAL

G/G

SYNC

INPUT

TERMINAL

R

INPUT

TERMINAL

BLUE

SELECTOR

@prower

SWITCH

TV

SYSTEM

SELECTOR

SWITCH

COLO

R

CONTRAST

SHARPNESS

OPERATION

TO

Operate

the

projector

switches

@

and

@

must

be

turned

ON,

and

switch

@

must

be

set

to

the

proper

input

signal

type.

Note:

When

the

separately

supplied

remote

controller

(ET-12R)

is

connected

to

the

video

projector,

switches

@

through

@

and

@

through

@

are

inoperable.

Please

use

the

remote

controiller

for

these

functions.

=

AS

Switch.

PURPOSE

MAIN

POWER

SWITCH

OFF

BL

=

ON

Switches

main

power

supply

ON/OFF.

MAIN

POWER

Power

ON/OFF

switch.

POWER

SWITCH

REMOTE

BH

=

ON

This

switch

is

set

to

the

OFF

position,

when

the

remote

control

is in

use.

RGB

LINE

VIDEO

VIDEO---Push

this

button

to

view

signals

input

via

the

VIDEO

input

terminal.

LINE

---Push

this

button

to

view

signals

input

via

the

LINE

input

terminal.

RGB_---Push

this

button

to

view

signals

input

via

the

RGB

INPUT

SELECTOR

input

terminal.

INPUT

SELECTOR

SWITCHES

This

switch

is

operable

only

when

RGB

signals

are

being

re-

NORMAL

.

a

ceived.

Use

this

switch

when

the

blue

portion

of

the

picture

is

weak.

FINE

BLUE

+

NI)

NORMAL

---Normal

blue.

BLUE

MONO-

FINE

BLUE

-:--A

finer

,

easier-on-the-eye,

blue.

BLUE

MONO:-:--White

picture

on

a

blue

back

ground.

Note:

When

Linear

or

TTL

RGB

signals

are

input

at

inappro-

BLUE

SELECTOR

priate

levels,

the

FINE

BLUE

and

BLUE

MONO

modes

might

not

operate

properly.

BLUE

SELECTOR

SWITCH

SECAM

,

This

switch

is

normally

set

at

AUTO.

PAL.

i

ity

i

TV

SYSTEM

igre:

eiedel

if

the

isk

eae

bad

.

the

use

of

dubbed

SELECTOR

SWITCH

Nee:

pes,

etc.,

reception

may

not

be

satis

ac

ory.

AUTO

*

In

that

case,

set

the

switch

to

the

appropriate

input

signal

using

a

screwdriver.

SYSTEM

The

click-stop

indicates

standard,

brightness.

===

(y

EDO

Adjust

to

the

appropriate

brightness

level

for

current

viewing

-

conditions.

Decrease

Increase

EC

ds

Adjust

to

a

desirable

color

intensity.

Decrease

Increase

E=0

==)

Es.

To

obtain

a

sharper

picture

rotate

the

control

clockwse.

For

a

softer

picture

rotate

the

control

counter-clockwse.

soft

sharp

|

EC

DO0-

Adjust

to

a

comfortable

viewing

level,

a

slightly

less

iniense

Low

High

picture

is

easier

on

the

eyes.

Color

0

eB

Adjust

for

proper

skin

tone.

red

gree

If

the

picture

rolls,

as

shown,

adjust

E)

ED

ttre

contro

uP

or

DOWN

until

it

UP

DOWN

stabilises.

Sh

PT-302

CONNECTING

OPTIONAL

EQUIPMENT

Connect

optional

equipment

(example)

according

to

following

illustration.

CASE

1:

Connection

to

a

video

source

—_—TV

Monitor

Video

Projector

HIZ

M0750

VIDEO

IN

aa

eT

Video

Camera

Hifi

VCR

beveneaienenenene

2

es

|

TV

Tuner

PERSONAL

COMPUTER

RGB

INTERFACE

(optional)

ET-11G/12G

=

—

SELECT

THE

APPROPRIATE

SYNC

TYPE

G.

G/SYNC

CASE

3:

Connection

to

the

remote

controller

ET-12R

(optional)

REMOTE

CONTROLLER

(optional)

hee

ET-12R

ERTAMIPILIER

Presentation

System

This

is

the

most

orthodox

VTR

playback

system.

Various

variations

can

be

de-

veloped

on

this

system

according

to

the

required

applications.

Applications:

®@

Conference

Rooms

®

Classrooms

@

Public

Areas

REMOTE

IN

Note:

The

PT-302

operates

on

positive

or

negative

SYNC.

The

SYNC

inverting

switch

is

factory

preset

to

the

‘““NOR-

MAL”

position

for

negative

SYNC.

For

positive

SYNC

set

the

switch

to

the

“REVERSE”

position.

During

installation

set

the

SYNC

invert

switch

for

the

appropriate

SYNC

polarity.

~#—_

REMOTE

CONTROL

CABLE

(opticonal)

ET-11C15.......

ET-11C30.......

ET-11C50.......

50

feet

(15

m)

100

feet

(30

m)

164

feet

(49.5

m)

GRRE

EE

Entertainment

System

1

This

system

is

ideal

for

use

for

parties,

ceremonies,

etc.

to’

be

held

in

large

places.

Great

effects

are

possible

with

the

powerful

video

images

from

colour

video

projectors,

when

combined

with

video

cameras

and

audio

equipment.

Applications:

@

Banquet

Halls

@

Lounges

Discos

Video

Camera

aaa

1

Remote

Control

_

Monitor

Unit

Effects

AV

Switcher

Controller

Monitor

Microphone

[

¥y

7

---

aa

Es

Controller

Audio

Mixer

Amp

-

Monitor

Pa

i

=

i

Wireless

Microphone

Tuner

Wireless

Amp

ERSTAIMIPILIERS

Business

Application

This

system

is

designed

to

concentrate

on

data

presentations

for

business,

con-

ferences,

showrooms,

etc.

Its

superb

re-

solution

and

capacity

to

match

various

types

of

personal

computers

make

it

ideal

for

upgrading

office-automation

systems

and

diversifled

video/data

services.

Applications:

®

Conference

Rooms

@

Training

Areas

@

Information

Displays

ae

I

en

HO

Video

Projector

-————__——]

7

feos]

[

¥

Special

Video

Camera

_

Monitor

Generator

AV

Switcher

Gal

Sa

—

Pcl

Screen

Hi-Fi

VTR

Monitor

Video

polices

ene

grttctt

His

T

ee

oe

ices

cea

v

ae

Had

Vo

'

t

!

VTR

!

rr

en

i

j

7

Video

Projector

i

I

OM

eR

Hm

Mtn

SHOE

RON

ONG

nl

en

nenpncenteeon

omen

:

RGB

Interface

——

Computer

~T

|

Be

cece

enw

ae

eer

rannsieramanraes

crane

BREE

EE

&

Entertainment

System

2

This

system

is

particularly

suited

to

such

recreational

facilities

as

bars,

restaurant,

dance

clubs,

etc.

A

wide

variety

of

atmos-

pheric

effects

can

be

produced.

When

used

together

with

stereo

sound,

a

re-

laxed

aura

of

“background

video“

and

“mood”

music,

or

dynamic

video

images

with

music

with

a

beat

to

match.

Applications:

@

Lounges

Discos

@

Restaurants

Hi-Fi

VTR

Monitor

Controller

Hi-Fi

VTR

r-

U

!

Monitor

'

Controller

a

eer

1

‘

—[

J

O

Monitor

Microphone

Turntable

a

ERIAIMPPILIERS

Educational

System

Ideal

for

a

wide

range

of

educational

acti-

vities,

particularly

as

an

effective

teaching

aid.

Applications:

@

Classrooms

®

Auditoriums

@

Lecture

Halls

Screen

{

Video

Projector

Ce

|

AV

Switcher

=

reas)

rot

Jt

Audio

Mixer

Amp

PT-302

rv

t

1

-~

eall--!

Microphone

AV

Switcher

aay

[

=

|

Video

shea

ctor

PT-302

DISASSEMBLY

INSTRUCTIONS

5)

“G”-Board

5.

HOW

TO

REMOVE

THE

PROJECTOR

TUBE

1.

HOW

TO

REMOVE

THE

TOP

COVER

4,

HOW

TO

OPEN

THE

PRINTED

CIRCUIT

BOARD

©

Remove

2

screws

@

in

fig.

8.

(WHEN

RED)

1)

Open

the

cover

of

control

panel.

1)

Cand

D,

V-Boards

@

Then

pull

the

G"-Board

toward

the

back

side

of

1)

Remove

the

two

retaining

2

screws

(L)

from

the

tube

2)

Remove

3

screws

()

in

fig.

2.

@

Loosen

2

screws

©)

to

counterclockwise

by

90°

in

the

deck,

and

carefully

lift

it

to

open

the

'G”

Board.

shown

in

fig.

12.

3)

Then

pull

the

Top

Cover

toward

the

back

side

of

the

fig.

5.

2)

Remove

the

lens

grill

shown

in

fig.

3.

(Remove

4

screws

deck

and

carefully

lift

it

for

removal.

@

The

lift

the

rear

of

the

chassis

to

open

the

“C",-

®).

3)

Remove

the

anode

lead

@)

from

the

high

voltage

distributor

shown

in

fig,

13.

4)

Remove

the

LR

printed

circuit

board

(N)

in

fig.

13.

5)

Remove

the

retaining

screw

of

the

neck

shield

©)

and

“D"

V-Board.

D-Board-7”

M-Board

3

screws

2

screws

G-Board

remove

the

neck

shield

©

in

fig.

13.

w

@

(3)

6)

Remove

the

retaining

screw

of

the

deflecting

coil

@

Fig.

8

and

draw

out

the

centering

magnet

®

and

the

diflecting

Cover

of

6)

“K’’-Board

coil

S)

in

fig.

13.

<

control

panel

@

Remove

the

Front

Panel.

7)

Remove

the

grounding

lead

from

the

tube.

@

Then

carefully

pull

and

lift

the

Terminal

Panel

for

8)

Remove

the

4

retaining

screws

@®

from

the

tube

and

removal

in

fig.

9.

draw

it

out

shown

in

fig.

14.

@

Remove

2

screws

(1)

in

fig.

10.

2)

“A’

-

“B"-Boards

@

Then

lift

and

pull

out

the

““K’'-Board.

@

Remove

a

1

screw

©

in

fig.

6,

and

remove

the

P.C-Board

fixing

metal.

Fig.

2

@

Then

carefully

pull

and

lift

the

‘A’

and

B”

Boards

for

removal.

2.

HOW

TO

REMOVE

THE

LENS

GRIL

1)

Remove

4

screws

in

fig.

3.

2)

Remove

the

Lens

Gril.

Terminal

anel

Lens

Gril

pi

P.C

Board

Fixing

Metal

Fig.

6

3)

"F’-Board

@

Remove

a

1

screw

©

in

fig.

7,

then

open

the

F”-

Board.

Fig.

3

3.

HOW

TO

REMOVE

THE

CONVERGENCE

CONTROL

COVER

1)

Open

the

cover

of

control

panel.

7)

“P”

and

‘‘Q’’-Boards

@

Remove

the

Front

Panel!

and

Terminal

Panel.

@

Remove

2

screws

YQ)

in

fig.

10.

@

Remove

4

screws

()

in

fig.

11,

and

lift

the

box

cover.

4

screws

(T)

@

Then

open

the

‘’P”’

and

‘‘0’'-Boards.

ee

2)

Remove

a1

screw

©)

in

fig.

4.

3)

Then

pull

the

Convergence

Control

Cover

toward

the

control

panel

side

for

removal.

Cover

of

Convergence

Box

cover

control

panel

control

cover

1

screw

©

Fig.

7

4)

“M"-Board

@

Remove

3

screws

@)

in

fig.

8.

@

Then

pull

the

‘’M’’-Board

toward

the

back

side

of

the

deck,

and

carefully

lift

it

to

open

the

‘‘M"’-Board.,

Fig.

4

Fig.

14

nl

fe)

:

-

Oo.

e

ANY

;

OLR

AS

LA

AT

ZAR

veLai\d

L

|

;

rave

wt

=

E

ie

VOLO,

<

g

\

G

TN

J

3

Se

|

/

W\-

°

38

eI

|

:

Be

Vek

fs

i

23

:

POW

ei

<

se

f

2

Q

r

;

&

;

d

fs

a

oe

Fig.

15

PT-302

CAUTIONS

FOR

SERVICING

HORIZONTAL

OSC.

DISABLE

CIRCUIT

TEST

REPAIR

PROCEDURES

OF

THE

HORIZONTAL

This

test

must

be

made

as

a

final

check

before

the

set

is

OSCILLATOR

DISABLE

CIRCUIT

returned

to

the

customer.

1.

Connect

a

DC

voltmeter

between

capacitor

C1413

+

1.

With

the

chassis

case

removed,

supply

a

nominal

120V

on

the

D-PCB

and

chassis

ground.

If

approximately

AC

to

the

set,

and

turn

the

set

on..

150V

is

not

present

at

that

point

find

the

cause.

Check

2.

Set

the

customer

controls

to

normal

operating

positions.

R535,

R591,

R1430,

R534,

C1413

and

D1408.

3.

Locate

Q1404

and

short

it’s

collector

to

the

emitter

2.

Connect

a

DC

voltmeter

between

capacitor

C518

+

on

with

a

jumper

wire.

Confirm

that

this

shorts

the

high

the

C-PCB

and

chassis

ground.

C518

+

potential

varies

voltage

and

that

the

raster

disappears.

from

nearly

OV

approx

to

nearly

4V

approx

when

4.

|f

this

does

not

occur,

the

Horizontal

Osc.

Disable

shorting

Q1404

(C-E).

If

this

does

not

occur,

find

the

Circuit

is

not

operating.

Follow

the

Horizontal

Oscil-

cause.

Check

R530,

R531, R537,

R538, R539,

R540,

lator

Disable

Circuit

Repair

Procedures

before

the

set

is

R541,

R542, R543,

R544,

C513,

C518, C519, C520,

returned

to

the

customer.

D507,

0510,

Q511

and

O512.

NOTE:

The

power

on/off

switch

must

be

turned

off

and

3.

Carefully

check

the

above

specified

parts

and

on

to

restore

operation.

circuits

and

parts.

When

the

circuit

is

repaired,

try

the

Horizontal

Oscillator

Disable

Circuit

Test

again.

4.

In

case

that

at least

one

of

R535, R591, R534,

D507,

and

the

FBT

is

replaced

follow

the

Adjustment

Pro-

cedure

for

the

Horizontal

Oscillator

Disable

Circuit

as

follows.

+27V

To

1C401

®

R542

R541

Q511

2SB709A

0.01

D1408

R1430

RvU1

220

R531.

+}

C513.

+]

C518

FBT

PULSE

Q512

2SD601A

QA207M3

—i2-—

Panasonic PT-302 Manuel utilisateur

Manuels Projecteur populaires d'autres marques