JVC AV 27D502 Diagram

SERVICE MANUAL

COLOR TELEVISION

AV-27D502

BASIC CHASSIS

AC

AV-27D502 AV-27D502

TV

/R

/S

SPECIFICATIONS

Items Contents

Dimensions (W × H × D)

················································································································································································································

Mass

················································································································································································································

TV RF System

················································································································································································································

Color Sound System

················································································································································································································

TV Receiving Channels and Frequency

VL Band

VH Band

UHF Band

················································································································································································································

CATV Receiving Channels and Frequency

Low Band

High Band

Mid Band

Super Band

Hyper Band

Ultra Band

Sub Mid Band

TV/CATV Total Channel

················································································································································································································

Intermediate Frequency

Video IF Carrier

Sound IF Carrier

Color Sub Carrier

················································································································································································································

Power Input

Power Consumption

················································································································································································································

Picture Tube

High Voltage

················································································································································································································

Speaker

Audio Power Output

················································································································································································································

Video / Audio Input (1 / 2 / 3)

29-5/8” × 23-1/4” × 19-1/2” / 75.2cm × 59.1cm × 49.4cm

71.3 Ibs/32.4kg

CCIR(M)

NTSC, BTSC System (Multi Channel Sound)

(02~06) 54MHz~88MHz

~13) 174MHz~216MHz

(07

(14

~69) 470MHz~806MHz

(02~06, A-8) by (02~06&01)

(07~13) by (07~13)

(A~1) by (14~22)

(J~W) by (23~36) (54MHz~804MHz)

(W+1~W+28) by (37~64)

(W+29~W+84) by (65~125)

(A8, A4~A1) by (01, 96~99)

180 Channels

45.75MHz

41.25MHz (4.5MHz)

3.58MHz

120V AC, 60Hz

123W

27” (68cm) Measured Diagonally

29kV±1.3kV (at zero beam current)

2” × 4-3/4” / 5 × 12cm Oval type × 2

5W × 2

Video(1,3) : 1Vp-p, 75Ø (RCA pin jack)

Audio(1,2,3) : 500mVrms ( -4dBs ), High Impedance (RCA pin jack)

S-Video ( Input 1 / 2 Over )

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

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

Component Input ( Input 2 )

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

PB/PR : 0.7Vp-p 75 Ø

—

················································································································································································································

Audio Output

(Variable)

················································································································································································································

AV Compu link EX Input

················································································································································································································

Antenna terminal

················································································································································································································

Remote Control Unit

Variable : More then 0~1550mVrms (+6dBs)

Low impedance (400Hz when modulated 100%)

3.5mm mini jack

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

RM-C301G-2A

(AA/R6/UM-3 battery × 2)

(RCA pin jack)

Design & specifications are subject to change without notice.

2 No. 51797

GOOD EARTH GROUND

0.15 µF AC-TYPE

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

PLACE THIS PROBE ON EACH EXPOSED METAL PART

1500Ø 10W

A V

This mark shows a fast

POWER CORD REPLACEMENT WARNING

Connecting thr white line side of power cord to “WHT” character side.

operating fuse, the letters indicated below show the rating.

PWB

WHT

PW

White line side

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. 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 (NEU-

TRAL) 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 10kØ 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 of overheating should be replaced. Always use the manufacturer's replacement components.

No. 51797 3

AV-27D502

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 1500Ø 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 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.).

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”.

AV-27D502

REPLACEMENT OF CHIP COMPONENT

CAUTIONS

a

1. Avoid heating for more than 3 seconds.

2. Do not rub the electrodes and the resist parts of the pattern.

3. When removing a chip part, melt the solder adequately.

4. Do not reuse a chip part after removing it.

SOLDERING IRON

a

1. Use a high insulation soldering iron with a thin pointed end of it.

2. A 30w soldering iron is recommended for easily removing parts.

REPLACEMENT STEPS

a

1. How to remove Chip parts

Resistors, capacitors, etc.

(1) As shown in the figure, push the part with tweezers and alter-

nately melt the solder at each end.

2. How to install Chip parts

Resistors, capacitors, etc.

(1) Apply solder to the pattern as indicated in the figure.

(2) Shift with tweezers and remove the chip part.

Transistors, diodes, variable resistors, etc.

(1) Apply extra solder to each lead.

SOLDER

(2) As shown in the figure, push the part with tweezers and alter-

nately melt the solder at each lead. Shift and remove the chip part.

SOLDER

(2) Grasp the chip part with tweezers and place it on the solder.

Then heat and melt the solder at both ends of the chip part.

Transistors, diodes, variable resistors, etc. (1) Apply solder to the pattern as indicated in the figure. (2) Grasp the chip part with tweezers and place it on the solder. (3) First solder lead A as indicated in the figure.

A

B

C

(4) Then solder leads B and C.

A

Note : After removing the part, remove remaining solder from the

pattern.

4 No. 51797

B

C

FEATURES

IC702

E2PROM 4k bit

IC701

MAIN MICON

IF2

SCL 1 SDA 1

SCL 0 SDA 0

AFC 2

AFC 1

Remote

control

unit

IC301

PIP

CONTROL

IC001

MTS, TONE

SURROUND CONTROL

TU001

TUNER 1

TU001

TUNER 2

IC101

1 CHIP

CONTROL

IC501

AVSW

CONTROL

Full-square CRT (cathode ray tube) reproduces fine textured pic-

•

ture in every detail. I2C bus control utilizes single chip ICs.

•

Built in Twin Tuner system.

•

Built-in HYPER-SURROUND system.

•

Built-in BBE.

•

Adoption of the Picture-In-Picture (PIP) function.

•

3 LINE DIGITAL COMB FILTER circuit improved picture quality.

•

a SYSTEM BLOCK DIAGRAM

AV-27D502

Component input terminal for talking best advantage of Component

•

Video Signal. Audio Video input terminal. (S-input ×2, V-input ×2)

•

Variable audio output terminal.

•

Closed-caption broadcasts can be viewed.

•

With AV COMPU LINK EX terminal.

•

No. 51797 5

AV-27D502

MAIN DIFFERENCE LIST

!

Part name

MAIN PWB SAC-1507A-M2 SAC-1506A-M2

CRT SOCKET PWB SAC-3507A-M2 SAC-3506A-M2

! PICTURE TUBE A68ADT25X01 A68QDN891X001

Model

AV-27D502/R AV-27D502/S

HOW TO IDENTIFY MODELS

The difference between AV-27D502/R and AV-27D502/S is in the PICTURE TUBE. As the result of the difference in PICTURE TUBE, the MAIN PWB also differ.

!

Part name

! RATING LABEL LC31139-001A-A

------------------------------------------------------------------------------------------------

Model

AV-27D502/R AV-27D502/S

INDICATED AV-27D502

INDICATED “R”

INDICATED “S”

6 No. 51797

FUNCTIONS

a FRONT PANEL

MENU

CHANNEL

OPERATE

VOLUME

POWER

AV-27D502

ON TIMER

MENU

CHANNEL

VOLUME

a FRONT PANEL DOOR OPENED

INPUT3

VIDEO

L/MONO-AUDIO-R

INPUT3 VIDEO/AUDIO TERMINAL

a REAR PANEL

POWER

a REMOTE CONTROL UNIT

(RM-C301G-2A)

CATV

VCR

CHANNEL

FREEZE

BBE

VOL

VCR CHANNEL

PREV NEXT

DVD

POWER

PIP

ON/MOVE

SWAP

INPUT

100+

1

4

7

CH

+

VCR/DVD

POWER

2

5

8

0

VOL

+

3

6

9

RETURN+

LIGHT

V CHIP

EXIT

PIP OFF

TV/VCR

TV

SOURCE

VIDEO STATUS

DISPLAY

SLEEP TIMER

HYPER SURROUND

RM-C301G

MUTING

MENU

PLAY FFREW

REC STOP

OPEN/CLOSE STILL/PAUSE

PAUSE

TV

No. 51797 7

AV-27D502

SPECIFIC SERVICE INSTRUCTIONS

DISASSEMBLY PROCEDURE

REMOVING THE REAR COVER

1. Unplug the power supply cord.

2. Remove the 12 screws marked A as shown in Fig.1.

3. Withdraw the REAR COVER toward you.

[CAUTION]

When reinstalling the rear cover, carefully push it inward after in-

•

serting the MAIN PWB into the rear cover groove.

REMOVING THE CHASSIS

After removing the rear cover.

•

1. Slightly raise the both sides of the chassis by hand and remove the 3 claws marked B under the chassis from the front cabinet as shown in Fig.1.

2. Withdraw the chassis backward along the rail in the arrow direction marked C as shown in Fig.1.

(If necessary, take off the wire clamp, connector’s etc.)

When conducting a check with power supplied, be sure to confirm

*

that the CRT earth wire is connected to the CRT SOCKET PWB and the MAIN PWB.

REMOVING THE TERMINAL BOARD

After removing the rear cover.

•

1. Remove the 4 screws marked D as shown in Fig.1.

2. When you pull out the TERMINAL BOARD in the direction of arrow marked E as shown in Fig.1, it can be removed.

REMOVING THE SPEAKER

After removing the rear cover.

•

1. Remove the 4 screws marked K as shown in Fig.1.

2. Withdraw the speaker backward.

3. Follow the same steps when removing the other hand speaker.

CHECKING THE MAIN PW BOARD

1. To check the back side of the MAIN PW Board.

1) Pull out the chassis. (Refer to REMOVING THE CHASSIS).

2) Erect the chassis vertically so that you can easily check the back side of the MAIN PW Board.

[CAUTION]

When erecting the chassis, be careful so that there will be no con-

•

tacting with other PW Board. Before turning on power, make sure that the CRT earth wire and

•

other connectors are properly connected.

WIRE CLAMPING AND CABLE TYING

1. Be sure 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.

REMOVING THE FRONT CONTROL AND FRONT AV INPUT PW BOARDS

After removing the rear cover and chassis.

•

1. Remove the 3 screws marked F and the 2 screws marked J as shown in Fig.1.

2. Then remove the FRONT CONTROL PWB and FRONT AV INPUT PWB.

(If necessary, take off the wire, connector’s etc.)

REMOVING THE LF PW BOARD

After removing the rear cover and chassis.

•

1. Lift the left side of the LF PWB while pressing the 2 PWB stoppers marked G in the arrow direction marked H as shown in Fig.1.

2. Then remove the LF PWB.

(If necessary, take off the wire, connector’s etc.)

8 No. 51797

FRONT CABINET

PICTURE TUBE

SPEAKER

K

(x4)

CRT SOCKET PWB

FRONT AV INPUT PWB

AV-27D502

SPEAKER

REAR COVER

(x2)

J

CLAW

(x3)

F

CLAW

B

K

(x4)

FRONT CONTROL PWB

PWB STOPPER

G

H

LF PWB

PWB

G

STOPPER

AV SELECTOR PWB

B

C

PIP PWB

CHASSIS BASE

MAIN PWB

E

D

(x4)

A

(x12)

Fig.1

No. 51797 9

AV-27D502

MEMORY IC REPLACEMENT

1. Memory IC

This model use a memory IC. This memory IC stores data for proper operation of the video and deflection circuits. When replacing, be sure to use an IC containing this (initial value) data.

2. Memory IC replacement procedure

Procedure Screen display

(1) Power off

Switch off the power and disconnect the power cord from the outlet.

(2) Replace the memory IC

Initial value must be entered into the new IC.

(3) Power on

Connect the power cord to the outlet and switch on the power.

(4) System constant check and setting

1) Press SLEEP TIMER key and, while the indication of “SLEEP TIMER 0 MIN.” is being displayed, press DISPLAY key and VIDEO STATUS

key on the remote control unit simultaneously.

2) The SERVICE MENU screen of Fig.1 is displayed.

3) While the SERVICE MENU is displayed, again simultaneously press the DISPLAY and VIDEO STATUS keys to display the Fig.2 SYSTEM CONSTANT screen.

4) Refer to the SYSTEM CONSTANT table and check the setting items. Where these differ, select the setting item with the MENU UP/DOWN key and adjust the setting with the MENU LEFT/RIGHT keys. (The letters of the selected item are displayed in yellow.)

5) After adjusting, release the MENU LEFT/RIGHT key to store the setting value.

6) Press the EXIT key twice to return the normal screen.

(5) Receive channel setting

Refer to the OPERATING INSTRUCTIONS(USER'S GUIDE) and set the receive channels (Channels Preset) as described.

(6) User settings

Check the user setting items according to Table 2. Where these do not agree, refer to the OPERATING INSTRUCTIONS (USER'S GUIDE) and set the items as described.

SERVICE MENU

PICTURE SOUND THEATER OTHERS PIP LOW LIGHT HIGH LIGHT RF AFC1 RF AFC2 VCO(CW) I2C BUS CTRL

SELECT BY OPERATE BY

Fig.1

SYSTEM CONSTANT

MODEL :99– PURITY : NO CCD : YES V-CHIP : YES CAN V-CHIP : YES

EXIT BY

99999

999999999 999

SELECT BY OPERATE BY

Fig.2

EXIT BY

EX

IT

EX

IT

(7) SERVICE MENU setting

Verify what to set in the SERVICE MENU, and set whatever is necessary.(Fig.1) Refer to the SERVICE ADJUSTMENT for setting.

10 No. 51797

AV-27D502

TABLE 1 (System Constant setting)

Setting item Setting content Setting value

AV-27F802 AV-32F802 AV-36F802 AV-27F702 AV-32F702

MODEL AV-27D502

AV-36D502 AV-32D502 AV-27D502 AV-36F702

AV-32D302 AV-36D302 AV-32D202 AV-36D202

AV-36230 AV-32230 AV-36260 AV-32260 AV-27260

PURITY

CCD

V-CHIP

CAN V-CHIP

YES NO

TABLE 2 (User setting value)

Setting item Setting value

1. Use remote controller keys

POWER OFF CHANNEL CH-02 VOLUME 5 INPUT TV HYPER SURROUND OFF BBE ON DISPLAY OFF SLEEP TIMER 0 VIDEO STATUS CHOICE PIP SOURCE CH-04 PIP ON (PIP POSITION) LEFT LOWR SIDE

2. Setting of MENU

NO

YES

PICTURE ADJUST

TINT CENTER COLOR CENTER PICTURE CENTER BRIGHT CENTER DETAIL CENTER NOISE MUTING ON SET VIDEO STATUS ALL CENTER

SOUND ADJUST

BASS CENTER TREBLE CENTER BALANCE CENTER MTS STEREO

CLOCK/TIMERS

SET CLOCK Unnecessary to set ON/OFF TIMER NO

INITIAL SETUP

TV SPEAKER ON COMPONENT-IN NO LANGUAGE ENG CLOSED CAPTION OFF AUTO TUNER SETUP TUNER MODE: AIR CHANNEL SUMMARY Unnecessary to set V-CHIP OFF SET LOCK CODE Unnecessary to set

No. 51797 11

AV-27D502

SERVICE ADJUSTMENTS

ADJUSTMENT PREPARATION:

1. You can make the necessary adjustments for this unit with either the remote control unit or with the adjustment equipment and parts

as given below.

2. Adjustment with the remote control unit is made on the basis of the initial setting values, however, the new setting values which set the

screen to its optimum condition may differ from the initial settings.

3. Make sure that AC power is turned on correctly.

4. Turn on the power for the set and test equipment before use, and start the adjustment procedures after waiting at least 30 minutes.

5. Unless otherwise specified, prepare the most suitable reception or input signal for adjustment.

6. Never touch any adjustment parts, which are not specified in the list for this adjustment-variable resistors, transformers, capacitors, etc.

7. Presetting before adjustment. Unless otherwise specified in the adjustment instructions, preset the following functions with the remote control unit.

User mode setting position

•

VIDEO STATUS STANDARD

HYPER SURROUND OFF

BASS, TREBLE, BALANCE CENTER

TINT, COLOR, PICTURE, BRIGHT, DETAIL

CENTER

MEASURING INSTRUMENT

1. DC voltmeter(or digital voltmeter)

2. Oscilloscope

3. Signal generator ( Pattern generator ) [NTSC]

4. Remote control unit

5. TV audio multiplex signal generator

6. Frequency counter

7. Resistor (1MØ)

ADJUSTMENT ITEMS

Check of B1 POWER SUPPLY

•

RF AGC adjustment

•

FOCUS adjustment

•

WHITE BALANCE adjustment

•

WHITE BALANCE (Low Light) adjustment WHITE BALANCE (High Light) adjustment PIP HIGH LIGHT WHITE BALANCE Adjustment

BRIGHT adjustment

•

SUB BRIGHT adjustment

CONTRAST adjustment

•

SUB CONTRAST adjustment

DEFLECTION adjustment

•

V CENTER and TRAPEZIUM adjustment V-SIZE and V-LINEARITY adjustment H POSITION adjustment PIP DISPLAY POSITION adjustment

CHROMA adjustment

•

SUB COLOR adjustment SUB TINT adjustment

MTS circuit adjustment

•

INPUT LEVEL check STEREO VCO adjustment SAP VCO adjustment FILTER check SEPARATION adjustment

12 No. 51797

ADJUSTMENT LOCATIONS

AV-27D502

FRONT CONTROL PWB FRONT AV INPUT PWB

POWER

VOL CH MENU

FRONT FRONT

007

006

LINE FILTER PWB

FRONT FRONT

P

F901 125V 5A

PW

E3

E1

MAIN PWB

CN006

SS

IC701 CPU

CN003

CN007

CN004

IC702

MPX

HV

DEG

Q511 Heatsink

R507

P

AV SELECTOR PWB

J501

J502

CN002 CN001

FRONT

TOP

CN001

CN002

J503

J601

TU001

PIP PWB

TU001

FRONT

TOP

CN003

CN005

S1

UPPER : FOCUS LOWER : SCREEN

TP-B

E2

TOP

CN005

CRT SOCKET PWB

TP-R

TP-G

CN004

TP-E

(SOLDER SIDE)

No. 51797 13

AV-27D502

BASIC OPERATION OF SERVICE MENU

1. TOOL OF SERVICE MENU OPERATION

Operate the SERVICE MENU with the REMOTE CONTROL UNIT.

2. SERVICE MENU ITEMS

In general, basic setting (adjustments) items or verifications are performed in the SERVICE MENU.

PICTURE ............................... This sets the setting values (adjustment values) of the VIDEO/CHROMA and DEFLECTION circuits.

•

SOUND .................................. This sets the setting values (adjustment values) of the AUDIO circuit.

•

THEATER .............................. This is used when the THEATER MODE is adjusted.

•

OTHERS ................................ This is used when the OTHERS MODE is adjustment.

•

PIP ......................................... This sets the setting values (adjustment values) of the PIP circuit.

•

LOW LIGHT ........................... This sets the setting values (adjustment values) of the WHITE BALANCE circuit.

•

HIGH LIGHT .......................... This sets the setting values (adjustment values) of the WHITE BALANCE circuit.

•

RF AFC1 ................................ This is used when the RF AFC1 MODE is verified. [Do not adjust]

•

RF AFC2 ................................ This is used when the RF AFC2 MODE is verified. [Do not adjust]

•

VCO (CW) .............................. This is not used for service.

•

I2C BUS CTRL ...................... This is used when ON/OFF of the I2C BUS CTRL is set. [Fixed ON]

•

3. Basic Operations of the SERVICE MENU

(1) How to enter the SERVICE MENU.

Press SLEEP TIMER key and, while the indication of “SLEEP TIMER 0 MIN.” is being displayed, press DISPLAY key and VIDEO STATUS key on the remote control unit simultaneously to enter the SERVICE MENU screen 1 shown in the next figure page.

(2) SERVICE MENU screen selection

Press the UP / DOWN key of the MENU to select any of the following items. (The letters of the selected items are displayed in yellow.)

PICTURE

•

THEATER

•

PIP

•

LOW LIGHT

•

RF AFC1

•

VCO(CW)

•

(3) Enter the any setting ( adjustment ) mode

PICTURE, SOUND and OTHERS mode

•

1) If select any of PICTURE, SOUND or OTHERS items, and the LEFT / RIGHT key is pressed from SERVICE MENU ( MAIN MENU ), the screen 2 will be displayed as shown in figure page later.

2) Then the UP / DOWN key is pressed, the PICTURE mode screen 3 or the SOUND mode screen 4 or the OTHER mode screen 5 is displayed, and the PICTURE, SOUND or OTHERS setting can be performed.

PIP mode

•

1) If select the PIP item, and the LEFT/RIGHT key is pressed from SERVICE MENU (MAIN MENU), the screen 6 will be displayed as shown in figure page later.

2) Then the UP/DOWN key is pressed, the PIP mode screen 7 is displayed, and the PIP setting can be performed.

THEATER, LOW LIGHT, HIGH LIGHT, RF AFC1, RF AFC2, VCO(CW) and I2C BUS CTRL mode

•

1) If select any of THEATER / LOW LIGHT / HIGH LIGHT / RF AFC1 / RF AFC2 / VCO (CW) / I2C BUS CTRL items, and the LEFT / RIGHT key is pressed from SERVICE MENU ( MAIN MENU ), the screens 8 9 10 11 12 13 14 will be displayed as shown in figure page later.

2) Then the settings or verifications can be performed.

SOUND

•

OTHERS

•

HIGH LIGHT

•

RF AFC2

•

I2C BUS CTRL

•

14 No. 51797

AV-27D502

1

SERVICE MENU (MAIN MENU) SCREEN PICTURE MODE

SERVICE MENU

PICTURE SOUND THEATER OTHERS PIP LOW LIGHT HIGH LIGHT RF AFC1 RF AFC2 VCO(CW) I2C BUS CTRL

SELECT BY OPERATE BY

10

HIGH LIGHT MODE

HIGH LIGHT

999 999

11

RF AFC1 MODE

EXIT BY

EX IT

[DO NOT ADJUST]

TOO HIGH GOOD TOO LOW

RF AFC1 ON FINE

SELECT BY OPERATE BY

EXIT BY

999

EX IT

2

SELECT BY

4

SOUND MODE OTHERS MODE

1. NOISE DET. STATUS

6

SCREEN PIP MODE

SELECT BY

EXIT BY

999

99999999

EXIT BY

EX IT

3

1. BRIGHT STATUS

5

1. OSD POS. 999

1. PIP BR STATUS

7

999

99999999

999

99999999

12

RF AFC2 MODE [DO NOT ADJUST]

TOO HIGH GOOD TOO LOW

RF AFC2 ON FINE

SELECT BY OPERATE BY

13

VCO (CW) MODE

999

EXIT BY

[DO NOT USE]

HIGH LEVEL REFERENCE LEVEL LOW LEVEL

SYNC : YES

14

I2C BUS CTRL MODE [FIXED ON]

I2C BUS ON

SELECT BY OPERATE BY

EXIT BY

EX IT

8

THEATER MODE (1/2) THEATER MODE (2/2)

TINT 999 B CUT. 999 COLOR 999 R DRIVE 999 PICTURE 999 B DRIVE 999 BRIGHT 999 DC REST. 999 DETAIL 999 BLK ST. 999 R CUT. 999 GMM PNT 999 G CUT. 999

SELECT BY OPERATE BY

9

LOW LIGHT MODE

EX IT

BRIGHT

999 999

999

EXIT BY

PAGE 1/2

999

EX IT

CD MAT. 99 CMP CD M 99 RY GAIN 99 CMP RY G 99 GY PHASE 99 CMP GY P 99 CORING 99 CMP COR 99

SELECT BY OPERATE BY

PAGE 2/2

EXIT BY

EX IT

No. 51797 15

AV-27D502

(4) Setting method

1) UP / DOWN key of the MENU Select the SETTING ITEM.

2) LEFT / RIGHT key of the MENU Setting (adjust) the SETTING VALUE of the SETTING ITEM. When the key is released the SETTING VALUE will be stored (memorized).

3) EXIT key Returns to the previous screen.

(5) Releasing SERVICE MENU

1) After returning to the SERVICE MENU upon completion of the setting (adjustment) work, press the EXIT key again.

¤ The settings for LOW LIGHT and HIGH LIGHT are described in the WHITE BAL-

ANCE page of ADJUSTMENT.

1. BRIGHT STATUS

SETTING ITEM

99999999

PICTURE MODE

999

INITIAL SETTING VALUE (Adjust) SETTING VALUE

16 No. 51797

AV-27D502

INITIAL SETTING VALUE OF SERVICE MENU

1. Adjustment of the SERVICE MENU is made on the basis of the initial setting values; however, the new setting values which set the screen in its optimum condition may differ from the initial setting.

2. Do not change the initial setting values of the setting (Adjustment) items not listed in “ADJUSTMENT”.

PICTURE MODE

•

The four setting items in the video mode No.6 EXT BRI., No.7 EXT PIC., No.8 EXT COL. and No.9 EXT TINT are linked to the items in the TV MODE No.1 BRIGHT, No.2 PICTURE, No.3 COLOR and No.4 TINT, respectively. When the setting items in the TV mode are adjusted, the values in the setting items in the video mode are revised automatically to the same values in the TV mode.(The initial setting values given in ( ) are off-set values.) When the four items (No.6, 7, 8 and 9) are adjusted in the video mode, the setting values in each item are revised independently.

No. Setting (Adjustment) item Variable range Initial setting value

1 BRIGHT 000 — 127 063

2 PICTURE 000 — 127 080

3 COLOR 000 — 127 072

4 TINT 000 — 127 065

5 TV DETAIL 000 — 063 045

6 EXT BRIGHT ±025 ±001

7 EXT PICT. ±025 ±002

8 EXT COLOR ±025 ±002

9 EXT TINT ±025 –004

10 EXT DETAIL 000 — 063 045

11 CMP BRIGHT ±025 –003

12 CMP PICT. ±025 +006

13 CMP COLOR 000 — 127 080

14 CMP TINT 000 — 127 068

15 CMP DETAIL 000 — 063 050

16 CMP R CUT ±025 –011

17 CMP G CUT ±025 ±000

18 CMP B CUT ±025 –001

19 CMP R DRV ±025 ±000

20 CMP B DRV ±025 ±000

21 WPL 000 / 001 001

22 B. B. SW 000 / 001 000

23 C TRAP 000 / 001 000

24 CORING 000 / 001 000

25 CMP CORING 000 / 001 001

26 TV SHARPF 000 / 001 001

27 EXT SHARPF 000 / 001 001

28 CMP SHARPF 000 / 001 001

29 RGB CONT 000 — 063 031

30 TV ID SENS 000 / 001 000

31 EXT ID SEN 000 / 001 001

32 F ID 000 / 001 000

33 Y MUTE 000 / 001 000

34 AUDIO ATT 000 — 127 127

35 SUB CONT 000 — 015 008

No. 51797 17

AV-27D502

No. Setting (Adjustment) item Variable range Initial setting value

36 R Y GAIN 000 / 001 001

37 CMP R Y GA 000 / 001 001

38 G Y PHASE 000 / 001 000

39 CMP G Y PH 000 / 001 000

40 CD MATRIX 000 — 003 003

41 CMP CD MAT 000 — 003 002

42 BLACK ST 000 — 003 001

43 DC REST 000 — 003 001

44 COLOR GMM 000 / 001 000

45 UV/CBCR 000 / 001 001

46 AT FLESH 000 / 001 000

47 ABL GAIN 000 — 003 000

48 ABL ST PNT 000 — 003 003

49 RGB ABCL 000 / 001 001

50 TV BPF TOF 000 / 001 000

51 EXT BPF TOF 000 / 001 000

52 GMM PNT 000 — 003 003

53 SVM GAIN 000 — 003 003

54 CMP SVM GA 000 — 003 003

55 SVM PHASE 000 / 001 000

56 AUDIO SW 000 / 001 000

57 BUZZ 000 / 001 000

58 IF FREQ 000 / 001 000

59 RF AGC 000 — 063 045

60 AFT MUTE 000 / 001 000

61 AFT SENS 000 / 001 001

62 R/G DRV SW 000 / 001 001

63 BLK SW 000 / 001 000

64 V S COR 000 — 015 012

65 V LIN 000 — 015 007

66 V SIZE 000 — 127 074

67 V AGC 000 / 001 000

68 V CENTER 000 — 063 053

69 TV AFC 000 — 003 000

70 EXT AFC 000 — 003 002

71 V POSI 000 — 007 000

72 H POSI 000 — 031 016

73 H SIZE 000 — 063 023

74 TV V FREQ 000 — 003 000

75 EXT V FREQ 000 — 003 003

76 SIDE PIN 000 — 063 027

77 STAND BY 000 / 001 000

78 TRAPEZ 000 — 063 035

79 V RAMP REF 000 / 001 001

80 V 48HZ 000 / 001 000

81 V EHT 000 — 007 000

82 TOP PIN 000 — 031 010

18 No. 51797

AV-27D502

No. Setting (Adjustment) item Variable range Initial setting value

83 H EHT 000 — 007 000

84 BTM PIN 000 — 031 012

85 V BLK LOW 000 — 003 000

86 V BLK UP 000 — 003 000

87 CAPTION IN 000 / 001 000

88 H BLK 000 / 001 000

89 SCREEN 000 / 001 000

90 ACB SW 000 / 001 000

91 ACB PULSE 000 — 015 007

92 OVER MODU 000 / 001 001

93 APACON LIM 000 / 001 001

94 TEST 000 — 255 128

95 RF S/N TY 000 — 002 002

96 EXT S/N TY 000 — 002 002

97 RF SN YC E 000 — 255 005

98 RF SN YC F 000 — 255 016

99 RF SN YC G 000 — 063 032

100 RF SN YC H 000 — 255 025

101 EX SN YC E 000 — 255 005

102 EX SN YC F 000 — 255 016

103 EX SN YC G 000 — 063 032

104 EX SN YC H 000 — 255 025

105 RF SN VC 1 000 — 063 000

106 RF SN VC 2 000 — 063 007

107 RF SN VC 3 000 — 063 014

108 RF SN VC 4 000 — 063 021

109 EX SN VC 1 000 — 063 000

110 EX SN VC 2 000 — 063 007

111 EX SN VC 3 000 — 063 014

112 EX SN VC 4 000 — 063 021

113 COR LEVEL 000 — 003 003

114 VNR CHK 000 — 255 003

115 YC SN TIME 000 — 255 005

116 VC SN TIME 000 — 255 005

117 VM DATA A ±127 +008

118 VM DATA B ±127 –004

119 VM DATA C ±127 –016

120 VM DATA D 000 / 001 000

121 VC SN STOP 000 — 255 010

122 CH MUTE 00/001 000

123 VM OFF TY 000/001 000

124 VC VM OFF 000/001 001

125 YC VM OFF 000 — 255 255

126 F LOCK 000 — 002 002

127 VF LOCK EX 000/001 000

128 PURI RGB 000 — 063 031

129 PURI BCK 000/001 000

No. 51797 19

AV-27D502

SOUND MODE

•

No. Setting (Adjustment) item Variable range Initial setting value

1 NOISE DET. 000 / 001 001

2 IN LEVEL 000 — 063 025

3 FH MONITOR 000 / 001 000

4 STEREO VCO 000 — 063 030

5 PILOT CAN. 000 / 001 000

6 FILTER 000 — 063 030

7 LOW SEP. 000 — 063 028

8 HI SEP. 000 — 063 025

9 5FH MON. 000 / 001 000

10 SAP VCO 000 — 063 003

11 IN GAIN 000 / 001 000

12 FIL. OFFSET ±010 ±000

13 BBE BASS ±010 +003

14 BBE TRE ±010 +003

THEATER MODE

•

Setting (Adjustment) item Variable range Initial setting value

TINT ±20 –06

COLOR ±20 –03

PICTURE ±50 –15

BRIGHT ±20 ±00

DETAIL ±20 +03

R CUT. ±20 ±00

G CUT. ±20 ±00

B CUT. ±20 ±00

R DRIVE ±99 +07

B DRIVE ±99 –25

DC REST. 00 — 03 01

BLK ST. 00 — 03 00

GMM PNT 00 — 03 01

CD MATRIX 00 — 03 01

RY GAIN 00 / 01 01

GY PHASE 00 / 01 00

CORING 00 / 01 01

CMP CD M 00 — 03 01

CMP RY G 00 / 01 01

CMP GY P 00 / 01 00

CMP COR 00 / 01 01

20 No. 51797

AV-27D502

OTHERS MODE

•

No. Setting (Adjustment) item Variable range Initial setting value

1 OSD POS. 000 — 007 002

2 CCD POS. 000 — 015 003

3 EOSEL 000 / 001 000

4 MENU COLOR 000 — –030 –010

5 MENU PICT. 000 — –030 –010

6 MENU BRI. 000 — –030 –010

PIP MODE

•

No. Setting (Adjustment) item Variable range Initial setting value

1 PIP BR 000 — 015 005

2 PIP PICT 030 — 045 045

3 PIP TINT 000 — 063 036

4 PIP COL 000 — 015 010

5 P R CUT 000 — 015 003

6 P G CUT 000 — 015 000

7 P B CUT 000 — 015 002

8 P R DR 000 — 255 052

9 P G DR 000 — 255 055

10 P B DR 000 — 255 060

11 LEFT POS. 000 — 255 020

12 RIGHT POS. 000 — 255 017

13 UPPER POS. 000 — 127 012

14 LOWER POS. 000 — 127 011

15 PICT LOCK 000 / 001 001

16 SELDEL 000 — 015 000

17 AGCFIX 000 / 001 001

18 AGCADST 000 / 001 000

19 AGC 000 — 015 007

20 VSPDEL 000 — 031 000

21 VSPISQ 000 / 001 001

22 YCOR 000 / 001 001

23 XFREQF 000 / 001 001

24 WTCHDG 000 / 001 001

25 COLON 000 / 001 000

26 ACQNEW 000 / 001 000

27 DSTDET 000 / 001 001

28 CRIBEOK 000 / 001 000

29 FCBEOK 000 / 001 000

30 NOCRID 000 / 001 000

31 NONSED 000 / 001 000

No. 51797 21

AV-27D502

LOW LIGHT MODE

•

Setting (Adjustment) item Variable range Initial setting value

R CUTOFF 0 — 255 085

G CUTOFF 0 — 255 085

B CUTOFF 0 — 255 085

HIGH LIGHT MODE

•

Setting (Adjustment) item Variable range Initial setting value

R DRIVE 0 — 127 060

B DRIVE 0 — 127 060

RF AFC1 MODE

•

Setting (Adjustment) item Variable range Initial setting value

RF AFC1 ON / OFF ON

FINE -77 — +77 ± × ×

RF AFC2 MODE

•

Setting (Adjustment) item Variable range Initial setting value

RF AFC2 ON / OFF ON

FINE -77 — +77 ± × ×

I2C BUS CTRL MODE

•

Setting (Adjustment) item Variable range Initial setting value

I2C BUS ON/OFF [FIXED ON]

DO NOT ADJUST

22 No. 51797

ADJUSTMENTS

B1 POWER SUPPLY

Item

Measuring

instrument

AV-27D502

Test point Adjustment part Description

Check of B1 POWER SUPPLY

DC Voltmeter R507 C504

ADJUSTMENT OF RF AGC

Item

RF AGC adjustment

Measuring

instrument

1. Receive a black-and-white signal.

side (B1)

Q511 heatsink ( )

Test point Adjustment part Description

No.59 RF AGC

2. Connect the DC Voltmeter to R507 C504 side (B1) and Q511 heatsink ( ).

3. Confirm that the voltage is DC134V .

1. Receive a broadcast.

2. Select the No.59 RF AGC of the PICTURE MODE.

3. Press the MUTE key of the remote control unit and turn off color.

4. With the LEFT key of the remote control unit, get noise in the screen picture. (0 side of setting value)

5. Press the RIGHT key of the remote control unit and stop when noise disappears from the screen.

6. Change to other channels and make sure that there Is no irregularity.

7. Press the MUTE key and get color out.

+2V

-2V

ADJUSTMENT OF FOCUS

Item

FOCUS adjustment

Measuring

instrument

Signal generator

Test point Adjustment part Description

FOCUS VR [In HVT]

H VR [In HVT]

Notes:

• Proceed to the following this adjustment after having completed the

adjustments of B1 POWER SUPPLY, SUB BRIGHT and PICTURE.

• Set VIDEO STATUS to “STANDARD”.

• The final adjustment of convergence must be done after the FOCUS

adjustment. (Convergence is changed by FOCUS adjustment.)

1. Receive a crosshatch signal.

2. While looking at the screen center, adjust the FOCUS VR so that the horizontal lines will be clear and in fine detail.

3. Adjust the H VR so that the vertical lines will be clear and in fine detail.

4. Make sure that the picture is in focus even when the screen gets darkened.

No. 51797 23

AV-27D502

ADJUSTMENT OF WHITE BALANCE

Item

Measuring

instrument

Test point Adjustment part

Description

WHITE BALANCE (Low Light) Adjustment

Signal generator

[LOW LIGHT] MODE

BRIGHT

999

R CUTOFF

REMOTE CONTROL UNIT

H.LINE ON

999 999 999

G CUTOFF

H.LINE OFF EXIT

123

R CUTOFF G CUTOFF B CUTOFF

456

R CUTOFF G CUTOFF B CUTOFF

789

No.1 BRIGHT

R CUTOFF G CUTOFF B CUTOFF

SCREEN VR [In HVT]

BRIGHT B CUTOFF

Note :

Set VIDEO STATUS to “STANDARD”.

1. Receive a black-and-white signal.(Color off)

2. Select the [LOW LIGHT] MODE from the SERVICE MENU.

3. Set the initial setting value of BRIGHT is 063 with the LEFT / RIGHT key of the remote control unit.

4. Set the initial setting value of R CUTOFF, G CUTOFF and B CUTOFF is 085 with the 4 to 9 key of the remote control unit.

5. Display a single horizontal line by pressing the 1 key of the remote control unit.

6. Turn the screen VR all the way to the left.

7. Turn the screen VR gradually to the right from the left until either one of the red, blue or green colors appears faintly.

8. Adjust the two colors which did not appear until the single horizontal line that is displayed becomes white using the 4 to 9 keys of the remote control unit.

9. Turn the screen VR to where the single horizontal line glows faintly.

10.Press the 2 key to return to the regular screen.

9 The 3 EXIT key is the cancel key for the WHITE BALANCE.

WHITE BALANCE (High Light) Adjustment

Signal generator

[HIGH LIGHT] MODE

999

R DRIVE

REMOTE CONTROL UNIT

H.LINE ON

HIGHT LIGHT

H.LINE OFF EXIT

999

123

R DRIVE B DRIVE

456

R DRIVE B DRIVE

789

R DRIVE B DRIVE

B DRIVE

Notes:

• Proceed to the following this adjustment after having completed the adjustment of LOW LIGHT WHITE BALANCE.

• Set VIDEO STATUS to “STANDARD”.

1. Receive a black-and-white signal. (Color off)

2. Select the [HIGH LIGHT] MODE from the SERVICE MENU.

3. Set the initial setting value of R DRIVE and B DRIVE is 060 with the 4 , 6 , 7 and 9 keys of the remote control unit.

4. Adjust the screen until it becomes white using the 4 , 6 , 7 and 9 keys of the remote control unit.

9 The 3 (EXIT) key is the cancel key for the WHITE BALANCE.

24 No. 51797

AV-27D502

Item

PIP HIGH LIGHT WHITE BALANCE

Measuring

instrument

Signal generator

ADJUSTMENT OF BRIGHT

Item

SUB BRIGHT Adjustment

Measuring

instrument

Test point Adjustment part Description

No.8 P R DR No.10 P B DR

PIP screen

Main screen

Test point Adjustment part Description

No.1 BRIGHT Notes:

Notes:

• Proceed to the following this adjustment after having completed the adjustments of LOW LIGHT WHITE BALANCE and HIGH LIGHT WHITE BALANCE for the main picture.

• Set VIDEO STATUS to “STANDARD”.

1. Receive a black-and-white signal. (Color off)

2. Select the PIP MODE from the SERVICE MENU.

3. Then adjust the white color of the PIP screen using the No. 8 P R

DR and the No. 10 P B DR of the PIP MODE so that it is the same brightness as the main screen.

• Proceed to the following this adjustment after having completed the adjustments of LOW LIGHT WHITE BALANCE and HIGH LIGHT WHITE BALANCE.

• Set VIDEO STATUS to “STANDARD”.

ADJUSTMENT OF CONTRAST

Item

SUB CONTRAST Adjustment

Measuring

instrument

Test point Adjustment part Description

No.2 PICTURE

1. Receive a broadcast.

2. Select the No.1 BRIGHT of the PICTURE MODE.

3. Set the initial setting value of the No.1 BRIGHT with the LEFT /

RIGHT key of the remote control unit.

4. If the brightness is not best with the initial setting value, make fine

adjustment of the No.1 BRIGHT until you get the optimum brightness.

Notes:

• Proceed to the following this adjustment after having completed the adjustment of SUB BRIGHT.

• Set VIDEO STATUS to “STANDARD”.

1. Receive a broadcast.

2. Select the No.2 PICTURE of the PICTURE MODE.

3. Set the initial setting value of the No.2 PICTURE with the LEFT /

RIGHT key of the remote control unit.

4. If the contrast is not best with the initial setting value, make fine

adjustment of the No.2 PICTURE until you get the optimum contrast.

No. 51797 25

AV-27D502

ADJUSTMENT OF DEFLECTION

Item

Measuring

instrument

Test point Adjustment part Description

V CENTER and TRAPEZIUM Adjustment

V-SIZE and V-LINEARITY Adjustment

Screen size 90%

Signal generator

Screen size

No.68 V CENTER No.78 TRAPEZ

No.66 V SIZE No.65 V LIN

Picture size 100%

Note:

Proceed to the following this adjustment after having completed the adjustments of SUB BRIGHT and SUB CONTRAST.

1. Receive a crosshatch signal.

2. Adjust the No.68 V CENTER of the PICTURE MODE to be the same between the CRT vertical center and crosshatch vertical center.

3. Adjust the No.78 TRAPEZ of the PICTUER MODE to be the vertical lines straight.

4. Confirm the vertical lines to be straight. If it is not straight, adjust to be straight at the No.78 TRAPEZ.

Note:

Proceed to the following this adjustment after having completed the adjustments of SUB BRIGHT and SUB CONTRAST.

1. Receive a crosshatch signal.

2. Select the No.66 V SIZE of the PICTURE MODE to squeeze the laster.

3. Adjust the No.65 V LIN of the PICTURE MODE to be symmetrical.

4. Adjust the No.66 V SIZE until the vertical screen size is 90%.

H POSITION Adjustment

PIP DISPLAY POSITION Adjustment

UPPER POS.

LOWER POS.

Picture size 100%

Signal generator

LEFT POS. RIGHT POS.

No.72 H POSI

No.11 LEFT POS. No.12 RIGHT POS. No.13 UPPER POS. No.14 LOWER POS.

80% ±2%

Main screen size

Note:

Proceed to the following this adjustment after having completed the adjustments of FOCUS, SUB BRIGHT, SUB CONTRAST, V CENTER, TRAPEZIUM, V-SIZE and V-LINEARITY.

1. Receive a crosshatch signal.

2. Select the No.72 H POSI of the PICTURE MODE.

3. Adjust the No.72 H POSI until the screen will be horizontally centered.

Notes:

• Proceed to the following this adjustment after having completed the adjustments of V CENTER, TRAPEZIUM, V-SIZE, V-LINEARITY and H POSITION for the main picture.

• Set VIDEO STATUS to “STANDARD”.

1. Receive a broadcast.

2. Select the PIP MODE from the SERVICE MENU.

3. Then adjust the PIP screen size so that it occupies 80% ± 2% of the main screen area.

80% ±2%

Main screen size

26 No. 51797

ADJUSTMENT OF CHROMA

Item

Measuring

instrument

AV-27D502

Test point Adjustment part Description

SUB COLOR adjustment

Signal generator Oscilloscope Remote control unit

Y

Cy

W

TP-B TP-E(

No.3 COLOR

)

[CRT SOCKET PWB]

G

R

(A)

(–) 0V

B

Mg

AV-27D502/R +7V AV-27D502/S +4V

(+)

A (Vw-B)

Table 1

Notes:

• Proceed to the following this adjustment after having completed the adjustment of CONTRAST.

• Set VIDEO STATUS to “STANDARD”.

[ Method of adjustment without measuring instrument ]

1. Receive a broadcast.

2. Select the No.3 COLOR of the PICTURE MODE.

3. Set the initial setting value of the No.3 COLOR with the LEFT/RIGHT

key of the remote control unit.

4. If the color is not the best with the Initial setting value, make fine

adjustment of the No.3 COLOR until you get the optimum color.

Notes:

• Proceed to the following this adjustment after having completed the adjustment of CONTRAST.

• Set VIDEO STATUS to “STANDARD”.

[ Method of adjustment using measuring instrument ]

1. Input the full field color bar signal (75% white).

2. Select the No.3 COLOR of the PICTURE MODE.

3. Set the initial setting value of the No.3. COLOR with the LEFT/RIGHT

key of the remote control unit.

4. Connect the oscilloscope between TP-B and TP-E.

5. Adjust COLOR and bring the value of (A) in the illustration to the

voltage shown in the table 1.

SUB TINT adjustment

Signal generator Oscilloscope Remote control unit

Y

Cy

W

TP-B

No.4 TINT

TP-E( ) [CRT SOCKET PWB]

G

R

(–) 0V

Mg

B

(+)

(B)

AV-27D502/R +9V AV-27D502/S +5V

B (Vw-Mg)

Table 2

Notes:

• Proceed to the following this adjustment after having completed the adjustment of CONTRAST.

• Set VIDEO STATUS to “STANDARD”.

[ Method of adjustment without measuring instrument ]

1. Receive a broadcast.

2. Select the No.4 TINT of the PICTURE MODE.

3. Set the initial setting value of the No.4 TINT with the LEFT/RIGHT

key of the remote control unit.

4. If the tint is not the best with the initial setting value, make fine ad-

justment of the No.4 TINT until you get the optimum tint.

Notes:

• Proceed to the following this adjustment after having completed the adjustment of CONTRAST.

• Set VIDEO STATUS to “STANDARD”.

[ Method of adjustment using measuring instrument ]

1. Input the full field color bar signal (75% white).

2. Select the No.4 TINT of the PICTURE MODE.

3. Set the initial setting value of the No.4 TINT with the LEFT/RIGHT

key to the remote control unit.

4. Connect the oscilloscope between TP-B and TP-E.

5. Adjust TINT and bring the value of (B) in the illustration to the volt-

age shown in the table 2.

No. 51797 27

AV-27D502

ADJUSTMENT OF MTS CIRCUIT

Item

Measuring

instrument

Test point Adjustment part Description

MTS INPUT LEVEL check

MTS STEREO VCO adjustment

MTS SAP VCO adjustment

Signal generator

Frequency counter

Signal generator

Frequency counter

[MPX] Connector 2

pin AUDIO R

3 pin GND

[MPX] Connector 4 pin TP_952.5 3 pin GND 2 pin AUDIO_R

No.2 IN LEVEL

No.3 FH MONITOR

No.4 STEREO VCO

No.9 5FH MON.

No.10 SAP VCO

1. Select the No.2 IN LEVEL of the SOUND MODE.

2. Verify that the No.2 IN LEVEL is set at its initial setting value.

Note: Menu “MTS” is set to “STEREO”

1. Receive a RF signal (nonmodulated sound signal) from the antenna terminal.

2. Select the No.3 FH MONITOR of SOUND MODE, and change the setting value from 0 to 1.

3. Connect the Frequency Counter to pin 2 of [MPX] connector and GND (Pin 3 of [MPX] connector).

4. Select the No.4 STEREO VCO.

5. Set the initial setting value of the No.4 STEREO VCO with the LEFT/ RIGHT key of the remote control unit.

6. Adjust the No.4 STEREO VCO so that the frequency counter will display 15.73kHz±0.1kHz.

7. Select the No.3 FH MONITOR of the SOUND MODE, and reset the setting value from 1 to 0.

1. Receive a RF signal (non modulated sound signal) from the antenna terminal.

2. Connect between pin 4 of [MPX] connector and GND (Pin 3 of [MPX] connector) through 1MØ Resistor.

3. Select the No.9 5FH MON. of the SOUND MODE, and reset the setting value from 0 to 1.

4. Connect the Frequency Counter to pin 2 of [MPX] connector and GND (Pin 3 of [MPX] connector) .

5. Select the No.10 SAP VCO.

6. Set the initial setting value of the No.10 SAP VCO with the LEFT/ RIGHT key of the remote control unit.

7. Adjust the No.10 SAP VCO so that the frequency counter will display 78.67kHz±0.5kHz.

8. Select the No.9 5FH MON. of the SOUND MODE, and reset the setting value from 1 to 0.

MTS FILTER check

MTS SEPARATION adjustment

L-Channel signal waveform

1 cycle

TV audio multiplex signal generator

Oscilloscope

[MPX] Connector 1 pin AUDIO_L 2 pin AUDIO_R 3 pin GND

R-Channel crosstalk portion

Minimum

No.6 FILTER

No.7 LOW SEP.

No.8 HI SEP.

1. Select the No.6 FILTER of the SOUND MODE.

2. Verify that the No.6 FILTER is set at its initial setting value.

Note: Menu “MTS” is set to “STEREO”

1. Input a stereo L signal (300Hz) from the TV audio multiplex signal

2. Connect an oscilloscope to pin 1 of [MPX] connector, and display

3. Change the connection of the oscilloscope to pin 2 of [MPX] con-

4. Select the No.7 LOW SEP. of the SOUND MODE.

5. Set the initial setting value of the No.7 LOW SEP. with the LEFT/

6. Adjust the No.7 LOW SEP. so that the 300Hz signal level will be-

7. Change the signal to 3kHz, and connect an oscilloscope to pin 1 of

8. Adjust the No.8 HI SEP. so that the 3kHz signal level will become

28 No. 51797

generator to the antenna terminal.

one cycle portion of the 300Hz signal.

nector, and enlarge the voltage axis.

RIGHT key of the remote control unit.

come minimum.

[MPX] connector.

minimum.

HOW TO CHECK THE HIGH VOLTAGE HOLD DOWN CIRCUIT

1. HIGH VOLTAGE HOLD DOWN CIRCUIT

After repairing the high voltage hold down circuit shown in Fig. 1. This circuit shall be checked to operate correctly.

2. CHECKING OF THE HIGH VOLTAGE HOLD DOWN CIRCUIT

(1) Turn the POWER SW ON.

S1

(2) As shown in Fig. 1, set the resistor (between (3) Make sure that the screen picture disappears. (4) Temporarily unplug the power cord. (5) Remove the resistor (between S1 connector 2 & 3 ). (6) Again plug the power cord, make sure that the normal picture is displayed on the screen.

RY951

connector 2 & 3 ).

RESISTOR

24.5 kΩ ± 122 Ω 1/4 W

AV-27D502

POWER

ON OFF

R952

R532

D535

R951

R533

Q531

Q951

Q532

R534

+

C533

D534

D532 BW

D531

Fig. 1

23

R537 FR525

R535R538

S1 CONNECTOR

+

HEATER

T502

4

D525

C525

No. 51797 29

AV-27D502

SELF CHECK FUNCTIONS

1. Outline

This model has self check functions given below. When a malfunction has been detected, the POWER is turned off and the LED flashes to inform of the failure . The malfunction is detected by the signal input state of the control line connected to the microcomputer.

2. Self check items

Check item Details of detection Method of detection State of malfunction

Over-current protector

3. Self check indicating function

The self-check function begins detection about 5 seconds after power is supplied. In the event a malfunction is detected, the power is cut off immediately. At this time, the ON-TIMER LED flashes to inform of the malfunction.

[ON-TIMER LED indication]

The ON-TIMER LED flashes at 0.5 seconds intervals.

Operation of B1 protector circuit. The microcomputer detects at 1

second intervals. If NG is detected for more than 200 ms, a malfunction is interpreted.

POWER Supplied

After about 5 seconds

Start of detection

When a malfunction has been detected, the POWER is turned off. While the POWER is being turned off , the power key of the remote controller is not operational until the power code is taken out and put in again.

Malfunction is detected

POWER OFF

Flashing ON-TIMER LED

30 No. 51797

JVC AV 27D502 Diagram

Specifications and Main Features

Frequently Asked Questions

User Manual

CONTENTS

SPECIFICATIONS

SAFETY PRECAUTIONS

FEATURES

MAIN DIFFERENCE LIST

HOW TO IDENTIFY MODELS

FUNCTIONS

SPECIFIC SERVICE INSTRUCTIONS

SERVICE ADJUSTMENTS