JVC AV27230/R - Service Manual Immediate Download

No.51803

Apr. 2001

AV-27230

Apr. 2001

AV-27230/S

AV-27230/R

CONTENTS

! SPECIFICATIONS

! SAFETY PRECAUTIONS

! FEATURES

! MAIN DIFFERENCE LIST

! HOW TO IDENTIFY MODELS

! FUNCTIONS

! SPECIFIC SERVICE INSTRUCTIONS

! SERVICE ADJUSTMENTS

! PARTS LIST

OPERATING INSTRUCTIONS

1-1

STANDARD CIRCUIT DIAGRAM

2-1

SERVICE MANUAL

COLOR TELEVISION

BASIC CHASSIS

No.51803

AV-27230

SPECIFICATIONS

Contents

Items

AV-27230/S

AV-27230/R

Dimensions (W×

×H×

×D)

25-3/4"×23-3/8"×19-1/2" / 654mm×593mm×494mm

Mass

68.5 Ibs / 31.1 kg

Reception Format

NTSC, BTSC System (Multi-Channel Sound)

Reception Range

VHF, UHF

VL Band

VH Band

UHF Band

(0206) 54MHz88MHz

(0713) 174MHz216MHz

(1469) 470MHz806MHz

CATV

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)

181 Channels

Intermediate Frequency

Video IF Carrier

Sound IF Carrier

Color Sub Carrier

45.75MHz

41.25MHz (4.5MHz)

3.58MHz

Power Input

Power Consumption

120V AC, 60Hz

113W

Picture Tube

High Voltage

27" (68cm) Measured Diagonally

29kV±1kV (at zero beam current)

Speaker

Audio Power Output

2"×3-1/2" / 5×9cm Oval type×2

1.2W + 1.2W

Input terminal

Input 1

S-Video

Video(V)

Audio(L, R)

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

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

1Vp-p, 75 (RCA pin jack)

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

Input 2

Component Video

Y, Pb, Pr

1Vp-p 75(positive sync)

Input 3

(Front)

Video(V)

Audio(L, R)

1Vp-p, 75 (RCA pin jack)

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

Output terminal

Variable Audio Output (R/L)

More than 01550mVrms (+6dBs)

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

Antenna terminal

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

Remote Control Unit

RM-C306-1A

(AA/R6/UM-3 battery×2)

Design & specifications are subject to change without notice.

(54MHz804MHz)

No. 51803

AV-27230

SAFETY PRECAUTIONS

1. The design of this product contains special hardware, many

circuits and components specially for safety purposes. For

continued protection, no changes should be made to the

original design unless authorized in writing by the manufacturer.

Replacement parts must be identical to those used in the

original circuits. Service should be performed by qualified

personnel only.

2. Alterations of the design or circuitry of the products should not

be made. Any design alterations or additions will void the

manufacturer's

warranty

and

will

further

relieve

the

manufacturer of responsibility for personal injury or property

damage resulting therefrom.

3. Many electrical and mechanical parts in the products have

special safety-related characteristics. These characteristics are

often not evident from visual inspection nor can the protection

afforded

them

necessarily

obtained

using

replacement components rated for higher voltage, wattage, etc.

Replacement

parts

which

have

these

special

safety

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 replacement which

does not have the same safety characteristics as the

recommended replacement part shown in the parts list of

Service manual may cause shock, fire, or other hazards.

4. Use isolation transformer when hot chassis.

The chassis and any sub-chassis contained in some products

are connected 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. Don't short between the LIVE side ground and ISOLATED

(NEUTRAL) side ground or EARTH side ground when

repairing.

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

difference of the GND is shown by the LIVE : (") side 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 measuring apparatus (oscilloscope etc.)

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

EARTH side GND at the same time.

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

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

that the B1 setting should be checked 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, arcing and possible

component damage, therefore operation under excessive high

voltage conditions should be kept to a minimum, or should be

prevented. If severe arcing occurs, remove the AC power

immediately and determine the cause by visual inspection

(incorrect installation, cracked or melted high voltage harness,

poor soldering, etc.). To 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 check high voltage by drawing an arc. Use a high

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

the picture tube before attempting meter connection, by

connecting 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 dress

in the high voltage circuit area. Where a short circuit has

occurred,

those

components

that

indicate

evidence

overheating

should

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 cabinet (antenna

terminals, video/audio input and output terminals, Control

knobs, metal cabinet, screwheads, earphone jack, control

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

danger of electrical shock.

(1) Dielectric Strength Test

The isolation between the AC primary circuit and all metal parts

exposed to the user, 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 second.

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

rated up to 120V, and 3000V AC (r.m.s.) to an appliance 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 cord directly into the AC outlet (do not use a

line isolation transformer during this check.). Using a "Leakage

Current Tester", measure the leakage current from each

exposed metal part of the cabinet, particularly 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 exceed 0.2mA AC

(r.m.s.).

" Alternate Check Method

Plug the AC line cord 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. Connect a 1500 10W resistor paralleled

by a 0.15F 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 resistor 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, reverse 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 tropical 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

GROUND

PLACE THIS PROBE

ON EACH EXPOSED

METAL PART

AC VOLTMETER

(HAVING 1000/V,

OR MORE SENSITIVITY)

11. High voltage hold down circuit check.

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

shall be checked to operate correctly.

See item "How to check the high voltage hold down

circuit".

This mark shows a fast

operating fuse, the

letters indicated below

show the rating.

No.51803

AV-27230

FEATURES

" New chassis design enables use of a single board with

simplified circuitry.

" Users can make fun to connect the Digital Video Disk player with

the component video signal input terminal.

" Provided with miniature tuner (TV/CATV).

" Multifunctional remote control permits picture adjustment.

" Adoption of the CHANNEL GUARD function prevents the

specific channels from being selected, unless the "ID number" is

key in.

" I2C bus control utilizes single chip ICs.

" Adoption of the VIDEO STATUS function.

" Adoption of the ON/OFF TIMER function.

" Built-in V-CHIP system.

" With 75V/U in common (F-Type) ANT Terminal.

" SLEEP TIMER for setting in real time.

" Closed-caption broadcasts can be viewed.

" Built-in MTS system.

" Built-in HYPER-SURROUND system.

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

" Variable Audio output terminal.

" 2 LINE Digital Comb filter Improved picture quality.

MAIN DIFFERENCE LIST

Model name

Parts Name

AV-27230/S

AV-27230/R

MAIN PWB

SFD-1003A-M2

SFD-1004A-M2

ITC TUBE

A68QDN891X001

A68ADT25X01

HOW TO IDENTIFY MODELS

The difference between AV-27230/S and AV-27230/R is in the PICTURE TUBE.

As the result of the difference in picture tube, the MAIN PWB also differs.

MODEL

Parts name

AV-27230/S

AV-27230/R

RATING LABEL

LC31139-001A-A

Indicated AV-27230

Indicated "S"

Indicated "R"

No.51803

AV-27230

FUNCTIONS

AUDIO OUTPUT TERMINAL

INPUT1 TERMINAL(S, V, L, R)

INPUT2 TERMINAL(V/Y, PR, PB, L, R)

AERIAL SOCKET

REAR TERMINAL

FRONT PANEL CONTROL

VIDEO INPUT TERMINAL

AUDIO L INPUT TERMINAL

AUDIO R INPUT TERMINAL

MENU KEY

CHANNEL -/+ KEY (OPERATE KEY)

VOLUME -/+ KEY

POWER LED

ON TIMER LED

REMOCON WINDOW

TV / CATV

VIDEO STATUS

DISPLAY

SLEEP TIMER

HYPER SURROUND

MUTING

POWER

VCR / DVD

INPUT

CHANNEL KEYS

V-CHIP

EXIT

VCR CONTROL KEYS

REMOTE CONTROL UNIT [RM-C306]