JVC AV-21WM11/A Service Manual

SERVICE MANUAL

COLOUR TELEVISION

5218520038

AV-21WM11/A

BASIC CHASSIS

ECO

POWER

SENSOR

SYSTEM

PICTURE MODE

COLOUR

SOUND

TV/VIDEO

OFF

TIMER

CHANNEL

RETURN

0-/

SCAN

DISPLAY

MUTING

CHANNEL

VOLUME

REMOTE CONTROL UNIT RM-C364GY

TABLE OF CONTENTS

1 PRECAUTION. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1-3

2 SPECIFIC SERVICE INSTRUCTIONS. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1-4

3 DISASSEMBLY . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1-6

4 ADJUSTMENT . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1-12

5 TROUBLESHOOTING . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1-28

No.52185

2003/8

SPECIFICATION

Items Contents

Dimensions (W × H × D) 64.9cm × 46.6cm × 47.2cm Mass 24.6kg TV RF System B/G, I, D/K Colour System RF Mode PAL / SECAM

VIDEO Mode PAL / SECAM / NTSC3.58 / NTSC4.43

Receiving Frequency VHF Low 46.25MHz~140.25MHz

VHF High 147.25MHz~423.25MHz UHF 431.25MHz~863.25MHz CATV Mid: X-Z, S1-S10

Super: S11-S20 Hyper: S21-S41

Intermediate Frequency

Colour Sub Carrier Frequency PAL 4.43MHz

Power Input AC110V~AC240V, 50Hz / 60Hz Power Consumption 100W (Max) / 65W(Avg) Picture Tube Visible size: 51cm measured diagonally ( W : 41.6cm × H : 31.5cm) High Voltage 26.5kV±1.5kV (at zero beam current) Speaker 6.5cm × 13cm, Oval type × 2 Audio Power Output 3W (monaural) Aerial Input Terminal 75Ω unbalanced, coaxial Input Terminal Video 1V(p-p), 75Ω, RCA pin jack × 2 (Front / Rear)

Output Terminal Video 1V(p-p), 75Ω, RCA pin jack × 1

Headphone Jack 3.5mm mini jack Remote Control Unit RM-C364GY

VIF 38.0MHz SIF 32.5MHz(5.5MHz)

31.5MHz (6.5MHz)

32.0MHz (6.0MHz)

SECAM 4.40625MHz / 4.25MHz NTSC 3.58MHz / 4.43MHz

Audio 500mV(rms) (-4dBs), High impedance,

RCA pin jack × 2 (Front) / (Rear)

Audio 500mV(rms) (-4dBs), Low impedance, RCA pin jack × 1

(Battery size : AA / R6 / UM-3 × 2)

Design and specifications are subject to change without notice.

1-2 (No.52185)

SECTION 1

PRECAUTION

1.1 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 by them necessarily be obtained by 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) 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 the LIVE side GND and ISOLATED (NEUTRAL) side GND or EARTH side GND at the same time with a measuring apparatus (oscilloscope etc.). If above note will not be kept, a fuse or any parts will be broken.

(5) 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).

(6) The high voltage appli ed to the picture tube must confo rm

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.

(7) Do not check high voltage by d rawing 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 gr ound frame and connecting the other end of the lead through a 10kΩ 2W resistor to the anode button.

(8) When service is required, obse rve 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 of overheating should be replaced. Always use the manufacturer's replacement components.

(9) 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, screw heads, earphone jack, control shafts, etc.) to be sure the product is safe to operate without danger of electrical shock.

a) 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 3000V 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.

b) Leakage Current Chec k

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 1000Ω per volt or more sensitivity in the following manner. Connect a 1500Ω 10W resistor paralleled by a 0.15µF 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 ac ross 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.).

AC VOLTMETER (HAVING 1000 /V, OR MORE SENSITIVITY)

0.15 F AC-TYPE

PLACE THIS PROBE

1500 10W

GOOD EARTH GROUND

ON EACH EXPOSED METAL PART

(No.52185)1-3

SECTION 2

SPECIFIC SERVICE INSTRUCTIONS

2.1 FEATURES

• New chassis design enables use of an interactive on-screen control.

• Wide range voltage (110V~240V) AC power input.

• With AUDIO / VIDEO INPUT & OUTPUT terminal.

• MUTING button can reduce the audio level to zero instantly.

• Functional remote control to operate TV set (for channel select, volume control, power ON/OFF, etc.) from a distance.

C bus control utilizes single chip ICs for IF, V/C, DEF and VSM PRESET.

•I

• Built - in ECO MODE (ECONOMY, ECOLOGY) In accordance with the brightness in a room, the brightness and / of contrast of the picture can be adjusted automatically to make the optimum picture which is easy on the eye.

• Built - in ON TIMER, RETURN + & CHILD LOCK.

2.2 FUNCTIONS

 FRONT PANEL

MENU buttons

MENU button MENU - / + buttons

CHANNEL - / + buttons

VOLUME - / + buttons

ECO sensor

 REAR TERMINAL

AUDIO

VIDEO

CHANNEL

VOLUME

10 9 1 2 3

VIDEO

EXIT

AUDIO

ON TIMER

5 7

4 6

OUT

POWER

REMOTE CONTROL sensor

ON TIMER lamp

POWER lamp

MAIN POWER button

VIDEO / AUDIO terminal

HEADPHONE jack

AERIAL terminal

VIDEO INPUT terminal

AUDIO INPUT terminal

AUDIO OUTPUT terminal

VIDEO OUTPUT terminal

1-4 (No.52185)

 REMOTE CONTROL UNIT

z RM-C364GY

1 2

3 4

5 6

7 8

ECO

SENSOR

COLOUR

TV/VIDEO

OFF

TIMER

CHANNEL

SCAN

DISPLAY

CHANNEL

SYSTEM

SOUND

123

456

789

RETURN+

REMOTE CONTROL UNIT RM-C364GY

POWER

PICTURE

MUTING

VOLUME

MODE

-/--

10 11

14 15

ECO sensor key

SOUND SYSTEM key

2 3

COLOUR SYSTEM key

TV/VIDEO key

OFF TIMER key

CHANNEL SCAN key

RETURN + key

DISPLAY key

CHANNEL - / + keys

POWER key PICTURE MODE key

Number (CH.) keys

12 13

- / - - key

MUTING key MENU keys

MENU / keys MENU - / + keys

VOLUME - / + keys

(No.52185)1-5

SECTION 3

DISASSEMBLY

3.1 DISASSEMBLY PROCEDURE

3.1.1 REMOVING THE REAR COVER

(1) Unplug the power cord. (2) Remove the 9 screws [A] and 1 screw [B]. (3) Withdraw the REAR COVER toward you.

3.1.2 REMOVING THE MAIN PW BOARD

• Remove the REAR COVER. (1) Slightly raise the both side s of the MAIN PW BOARD by

hand and remove the MAIN PW BOARD from the FRONT CABINET.

(2) Withdraw the MAIN PW BOARD backward.

(If necessary, take off the wire clamp, connectors etc.)

3.1.3 REMOVING THE SPEAKER

• Remove the REAR COVER. (1) Remove the 4 screws [C]. (2) Follow the same steps when removing the other hand

SPEAKER.

3.1.4 CHECKING THE MAIN PW BOARD

• To check the back side of the PW BOARD. (1) Pull out the MAIN PW BOARD. (Refer to REMOVING THE

MAIN PW BOARD)

(2) Erect the PW BOARD vertically so that you can easily

check the back side of the PW BOARD.

CAUTION:

• When erecting the PW BOARD, be careful so that there will

be no contacting with other PW BOARD.

• Before turning on power, make sure that the CRT earth wire

and other connector are properly connected.

3.1.5 WIRE CLAMPING AND CABLE TYING

(1) Be sure to clamp the wire. (2) Never remove the cable tie used for tying the wires

together. Should it be inadvertently removed, be sure to tie the wires with a new cable tie.

1-6 (No.52185)

SPEAKER

FRONT CABINET

(4)

SPEAKER

CRT SOCKET PWB

(Within MAIN PWB)

MAIN PWB

(4)

POWER CORD

REAR COVER

(9)

(No.52185)1-7

3.2 MEMORY IC REPLACEMENT

3.2.1 MEMORY IC

This TV use memory IC. In the memory IC, there are memorized data for correctly operating the video and deflection circuits. When replacing the memory IC, be sure to use IC written with the initial values of data.

3.2.2 MEMORY IC REPLACEMENT PROCEDURE

(1) Power off

Switch the power off and disconnect the power plug from the wall outlet.

(2) Replace IC

Be sure to use memory IC written with the initial data values.

(3) Power on

Connect the power plug into the wall outlet and switch the power on.

(4) Check and set SYSTEM CONSTANT SET

SERVICE MENU

1.IF 2.V/C

3.DEF 4.VSM PRESET

5.PRESET

6.SETUP TOUR OFF

1-6 : SELECT DISP : EXIT

************ **.*** *** ** **** ***

Fig.1

• It must not adjust without adjustment signals. a) Press the [DISPLAY] key and the [PICTURE MODE]

key of the REMOTE CONTROL UNIT simultaneously.

SYSTEM CONSTANT- I

b) The SERVICE MENU screen of Fig. 1 will be

displayed.

c) While the SERVICE MENU is displayed, again press

the [DISPLAY] key and [PICTURE MODE] key simultaneously, and the SYSTEM CONSTANT SET screen of Fig. 2 will be displayed.

d) Check the setting values of the SYSTEM

CONSTANT SETTING. If the value is different, select the setting item with the [MENU /] key, and set

SYSTEM CONSTANT SET 1

COLOUR : TRIPLE BILINGUAL : NO TUNER : MU ECO SENSOR LANGUAGE : E/C/M/I

: SELECT

- / + : OPERATE DISP : EXIT

the correct value with the [MENU - / +] key.

e) Press the [DISPLAY] key twice, and return to the

SYSTEM CONSTANT- II

normal screen.

(5) Receive channel of setting

Refer to the OPERATING INSTRUCTIONS and set the receive channels (channels preset) as described.

(6) User Setting

Check the user setting value and if setting value is different, set the correct value.For setting, refer to the OPERATING INSTRUCTIONS.

(7) Setting of SERVICE MENU

Verify the setting items of the SERVICE MENU, and reset where necessary.For setting, refer to the ADJUSTMENT.

SYSTEM CONSTANT SET 2

B/B SOUND : OFF LOCK : 180 COLOUR AUTO QSS ALC : NO TEXT RATE

: SEL - / + : OPE DISP : EXIT

SYSTEM CONSTANT- III

KEY ASSIGNMENT OF REMOTE CONTROL UNIT

: YES

: NO : MINT

: 20

DISPLAY key

- / + key

1-8 (No.52185)

ECO

SENSER

COLOUR

TV/VIDEO

OFF

TIMER

CHANNEL

SCAN

DISPLAY

SYSTEM

CHANNEL

SOUND

123

456

789

RETURN+

VOLUME

POWER

PICTURE

MODE

MUTING

PICTURE MODE key

NUMBERS key

-/--

MENU / key

(RM-C364GY)

SYSTEM CONSTANT SET 3

AMP TUNER : NO VNR TEXT TABLE : CYL VOLUME PWM : POS

: SEL - / + : OPE DISP : EXIT

: YES

Fig.2

3.2.3 SYSTEM CONSTANT SETTING

Setting item Setting contents Setting value

COLOUR BILINGUAL TUNER ECO SENSOR LANGUAGE B/B SOUND LOCK COLOUR AUTO QSS ALC TEXT RATE AMP TUNER VNR TEXT TABLE

MULTI

YES

E/C/M/I

YES 10 20 ~ 230 240 250

YES

MINT

YES

10 20 40 80

YES

ARA

E/C

OFF

MQSS

CYL

PALTRIPLE

TRIPLE

YES

E/C/M/I

OFF

180

MINT

NO YES CYL

VOLUME PWM

POS

NEG

POS

3.2.4 FACTORY SETTING VALUE Setting item Setting value Setting item Setting value

SUB POWER ON CHANNEL PRESET Refer to OPERATING INSTRUCTION CHANNEL POSITION CHANNEL 1 ECO SENSOR OFF VOLUME About 10 VNR OFF TV/VIDEO TV AUTO SHUTOFF OFF COLOUR SYSTEM PAL ON TIMER PR1 0:00 SOUND SYSTEM B / G BLUE BACK OFF OFF TIMER 00 CHILD LOCK OFF PICTURE MODE (VSM) BRIGHT SETUP TOUR ON LANGUAGE ENGLISH

(No.52185)1-9

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