JVC AV27D503/S - Service Manual Immediate Download

No.51946

May 2002

AV-27D503

CONTENTS

SPECIFICATIONS

! SAFETY PRECAUTIONS

FEATURES

HOW TO IDENTIFY MODELS

! FUNCTIONS

SPECIFIC SERVICE INSTRUCTIONS

! SERVICE ADJUSTMENTS

! PARTS LIST

STANDARD CIRCUIT DIAGRAM

2-1

SERVICE MANUAL

COLOR TELEVISION

BASIC CHASSIS

No.51946

AV-27D503

SPECIFICATIONS

Items

Contents

Dimensions (W×

H×

29-5/8"×23-1/4"×19-1/2"

(752mm×591mm×494mm)

Mass

71.3Ibs (32.4kg)

TV System and Color system

TV RF System

Color System

Sound System

CCIR(M)

NTSC-M

BTSC (Multi Channel Sound)

TV Receiving Channels and Frequency

VL Band

VH Band

UHF Band

(0206) 54MHz88MHz

(0713) 174MHz216MHz

(1469) 470MHz806MHz

CATV Receiving Channels and Frequency

Low Band

High Band

Mid Band

Super Band

Hyper Band

Ultra Band

Sub Mid Band

TV/CATV Total Channel

(0206, A-8) by (0206&01)

(0713) by (0713)

(A1) by (1422)

(JW) by (2336)

(W+1W+28) by (3764)

(W+29W+84) by (65125)

(A8, A4A1) by (01, 9699)

180 Channels

Intermediate Frequency

Video IF Carrier

Sound IF Carrier

45.75 MHz

41.25 MHz (4.5MHz)

Color Sub Carrier

3.58 MHz

Power Input

120V AC, 60Hz

Power Consumption

123W

Picture Tube

27" (68cm) measured diagonally, Full Square

High Voltage

29kV±1.3kV (at zero beam current)

Speaker

2"×4-3/4" (5×12cm) Oval type×2

Audio Power Output

5W+5W

Input terminals

INPUT1

Video

S-Video

Audio (L,R)

INPUT2

Video

Component (Y,Pb,Pr)

Audio (L,R)

INPUT3

Video

(Front)

Audio (L,R)

1Vp-p 75 (RCA pin jack)

Y :1Vp-p positive (negative sync provided, when terminated with 75)

C: 0.286Vp-p (burst s ignal, when terminated with 75)

500mVrms (-4dBs), High Impedance (RCA pin jack)

1Vp-p 75 (RCA pin jack)

Y: 1Vp-p positive (negative sync provided, when terminated with 75)

PB/PR: 0.7Vp-p 75

500mVrms (-4dBs), High Impedance (RCA pin jack)

1Vp-p 75 (RCA pin jack)

500mVrms (-4dBs), High Impedance (RCA pin jack)

Audio Output

500mVrms(-4dBs)

Low Impedance (400Hz when modulated 100%) (RCA pin jack)

AV Compu link EX Input

3.5mm mini jack

Antenna terminal

75 (VHF/UHF) Terminal, F-Type Connector

Remote Control Unit

RM-C251 (AA/R6/UM-3 battery×2)

Design & specifications are subject to change without notice.

(54MHz804MHz)

No. 51946

AV-27D503

SAFETY PRECAUTIONS

1. The design of this product c ontains spec ial hardware, many

circuits and components s pecially for safety purposes. For

continued protection, no changes should be made to the

original des ign unless authorized in writing by the manufacturer.

Replacement parts must be identic al to thos e used in the

original circuits. Servic e should be performed by qualified

pers onnel only.

2. Alterations of the design or circuitry of the products s hould not

be made. Any design alterations or additions will void the

manufacturer's

warranty

and

will

further

relieve

the

manufacturer of respons ibility for pers onal injury or property

damage resulting therefrom.

3. Many electrical and mechanic al parts in the products have

special safety-related c haracteris tics. These charac teristics are

often not evident from visual inspection nor can the protection

afforded by

them necess arily

be obtained by

using

replac ement components rated for higher voltage, wattage, etc.

Replacement parts

whic h have thes e special

s afety

characteristics are identified in the parts list of Service manual.

Electrical components having such features are identified

by shading on the schematics and by (!

) on the parts list

in Service manual. The use of a substitute replac ement which

does not have the same safety characteristics as the

recommended replac ement part shown in the parts list of

Service manual may c aus e shock, fire, or other haz ards.

4. Use isolation transformer when hot chassis.

The chassis and any sub-chassis contained in s ome products

are c onnected to one side of the AC power line. An isolation

transformer of adequate capacity should be inserted between

the product and the AC power supply point while performing

any service on some products when the HOT chassis is

exposed.

5. Do n't short between the LIVE side ground and ISOLATED

(NEUTRAL) side ground or EARTH side ground when

repairing.

Some model's power c ircuit is partly different in the GND. The

differenc e of the GND is shown by the LIVE : (") s ide GND,

the ISOLATED(NEUTRAL) : (#) side GND and EARTH : ($)

side GND. Don't short between the LIVE side GND and

ISOLATED(NEUTRAL) side GND or EARTH side GND and

never measure with a meas uring apparatus (oscilloscope etc.)

the LIVE side GND and ISOLATED(NEUTRAL) side GND or

EARTH side GND at the s ame time.

If above note will not be kept, a fuse or any parts will be brok en.

6. If any repair has been made to the chassis, it is recommended

that the B1 setting should be chec ked or adjusted (See

ADJUSTMENT OF B1 POWER SUPPLY).

7. The high voltage applied to the picture tube must conform with

that specified in Service manual. Excessive high voltage can

cause an increase in X-Ray emission, arc ing and possible

component damage, therefore operation under excess ive high

voltage c onditions should be kept to a minimum, or should be

prevented. If severe arc ing occurs, remove the AC power

immediately and determine the cause by visual inspection

(incorrect installation, crac ked or melted high voltage harness,

poor s oldering, etc.). T o maintain the proper minimum level of

soft X-Ray emission, components in the high voltage circuitry

including the picture tube must be the exact replacements or

alternatives approved by the manufacturer of the complete

product.

8. Do not c hec k high voltage by drawing an arc. Us e a high

voltage meter or a high voltage probe with a VTVM. Discharge

the picture tube before attempting meter connection, by

connec ting a clip lead to the ground frame and connecting the

other end of the lead through a 10k 2W resistor to the anode

button.

9. When service is required, observe the original lead dress.

Extra precaution should be given to assure correct lead dres s

in the high voltage c ircuit area. W here a short circuit has

occurred, those c omponents that indic ate evidence of

overheating

s hould

replaced.

Always

use

the

manufacturer's replacement components.

10. Isolation Check

(Safety for Electrical Shock Hazard)

After re-assembling the product, always perform an isolation

check on the exposed metal parts of the c abinet (antenna

terminals, video/audio input and output terminals, Control

knobs, metal c abinet, screwheads, earphone jac k, c ontrol

shafts, etc.) to be sure the product is safe to operate without

danger of electrical shoc k.

(1) Dielectric Strength Test

The is olation between the AC primary circuit and all metal parts

exposed to the us er, particularly any exposed metal part having

a return path to the chassis should withstand a voltage of

1100V AC (r.m.s.) for a period of one sec ond.

(. . . . Withs tand a voltage of 1100V AC (r.m.s.) to an appliance

rated up to 120V, and 3000V AC (r.m.s.) to an applianc e rated

200V or more, for a period of one second.)

This method of test requires a test equipment not generally

found in the service trade.

(2) Leakage Current Check

Plug the AC line c ord directly into the AC outlet (do not use a

line is olation transformer during this check.). Using a "Leakage

Current Tester", measure the leakage current from each

exposed metal part of the cabinet, partic ularly any exposed

metal part having a return path to the chassis , to a known good

earth ground (water pipe, etc.). Any leakage current must not

exceed 0.5mA AC (r.m.s.).

However, in tropical area, this must not exc eed 0.2mA AC

(r.m.s.).

Alternate Check Method

Plug the AC line c ord directly into the AC outlet (do not use a

line isolation transformer during this check.). Use an AC

voltmeter having 1000 ohms per volt or more sensitivity in the

following manner. Connec t a 1500 10W resistor paralleled

by a 0.15 F AC-type capacitor between an exposed metal

part and a known good earth ground (water pipe, etc.).

Measure the AC voltage across the resistor with the AC

voltmeter. Move the res istor connection to each exposed metal

part, particularly any exposed metal part having a return path to

the chassis , and measure the AC voltage across the resistor.

Now, revers e the plug in the AC outlet and repeat each

measurement. Any voltage measured must not exceed 0.75V

AC (r.m.s.). This corresponds to 0.5mA AC (r.m.s.).

However, in tropic al area, this must not exceed 0.3V AC

(r.m.s.). This corresponds to 0.2mA AC (r.m.s.).

0.15F AC-TYPE

1500 10W

GOOD

EARTH

GR OUND

PLACE THIS PROBE

ON EACH EXPOSED

METAL PART

AC VOLTMETER

(HAVING 1000 /V,

OR MOR E SENSITIVITY)

11. High voltage hold down circuit check.

After repair of the high voltage hold down circuit, this circuit

shall be c hec ked to operate correctly.

See item "Ho w to check the high voltage hold down

circuit".

This mark shows a fast

operating fuse, the

letters indicated below

show the rating.

No. 51946

AV-27D503

FEATURES

" New chassis design enables use of a main board with simplified

circuitry.

" 3 LINE Digital Comb filter Improved pic ture quality.

" Full-square CRT (c athode ray tube) reproduc es fine textured

picture in every detail.

" With AV COMPU LINK EX terminal.

Closed-c aption broadcasts can be viewed.

" With AUDIO / VIDEO INPUT terminal.

S-VIDEO input terminal for taking best advantage of Super VHS.

" Audio output terminal.

" I2C bus control utilizes single chip ICs.

Becaus e built-in the BBE circ uit improved the sound of

conversation.

" DVD dec k output can inputs to c omponent video s ignal input

terminal.

" The hyper-surround system marks a reproduction of the acoustic

effects in a theater with strong appeal.

" Becaus e of built-in 2 tuner & PIP circuit, displays plural programs

on the screen at the same time.

" Built-in V-CHIP,V-CHIP CAN system

HOW TO IDENTIFY MODELS

How to recognize from the appearance of the model concerned is written below. Please distinguish from s everal

contents currently printed on the rating label

MODEL

Parts name

AV-27D503/S

AV-27D503/R

RATING LABEL

GQ30032-001A-A

INDICATED AV-27D503

FUNCTIONS (

)

FRONT PANEL

INPUT3 VIDEO terminal

MENU button

POWER button

INPUT3 AUDIO L terminal

CHANNEL -/+ buttons

MENU OPERATE

buttons

ON TIMER lamp

INPUT3 AUDIO R terminal

VOLUME -/+ buttons

REMOTE CONTROL sens or

INDICATED"

"R"

No. 51946

AV-27D503

FUNCTIONS(

)

REMOTE CONTROL UNIT (RM-C251)

INPUT 1 AUDIO R terminal

INPUT 2 AUDIO L/MONO terminal

COMPONENT Y terminal

INPUT 1 AUDIO L/MONO terminal

INPUT 2 VIDEO terminal

COMPONENT PB terminal

INPUT 1 VIDEO terminal

AUDIO OUT R terminal

COMPONENT PR terminal

INPUT 1 S-VIDEO

AUDIO OUT L terminal

VHF / UHF terminal

INPUT 2 AUDIO R terminal

AV COMPULINK EX terminal

REAR PANEL

POWER key

MENU key

EZ SURF key

PIP keys

INPUT key

CHANNEL keys

DISPLAY key

LIGHT key

SLEEP TIMER key

V-CHIP key

HYPER SUR. key

CH/( / )keys

VIDEO STATUS key

EXIT/PIP OFF key

THEATER PRO key

VCR CONTROL key

BBE key

VCR / DVD switch

MUTING key

TV / CATV switch

VOL/(/) keys

The CH-/+ and VOL-/+ k eys operate CHANNEL and

VOLUME normally.

Thes e keys are also used to navigate MENU system.

NOTE