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AV-27D502

SERVICE MANUAL
COLOR TELEVISION
BASIC CHASSIS

AV-27D502 /AR AV-27D502 /AS

GC

TV

CONTENTS
a SPECIFICATIONS ....................................................................................................................................2 a SAFETY PRECAUTIONS ........................................................................................................................3 a FEATURES ..............................................................................................................................................4 a MAIN DIFFERENCE LIST ........................................................................................................................5 a HOW TO IDENTIFY MODELS ..................................................................................................................5 a FUNCTIONS .............................................................................................................................................6 a SPECIFIC SERVICE INSTRUCTIONS ....................................................................................................7 a SERVICE ADJUSTMENTS ....................................................................................................................12 ¤ STANDARD CIRCUIT DIAGRAM (APPENDIX) .................................................................................. 2-1 a PARTS LIST ...........................................................................................................................................31
No. 51797C Dec. 2001

COPYRIGHT © 2001 VICTOR COMPANY OF JAPAN, LTD.

AV-27D502

SPECIFICATIONS
Items
Dimensions (W × H × D) Mass

Contents
29-5/8" × 23-1/4" × 19-1/2" / 75.2cm × 59.1cm × 49.4cm 71.3 Ibs/32.4kg CCIR(M)

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TV RF System

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Color Sound System NTSC, BTSC System (Multi Channel Sound)

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TV Receiving Channels and Frequency VL Band VH Band UHF Band Low Band High Band Mid Band Super Band Hyper Band Ultra Band Sub Mid Band TV/CATV Total Channel Video IF Carrier Sound IF Carrier Color Sub Carrier Power Input Intermediate Frequency CATV Receiving Channels and Frequency (02~06) 54MHz~88MHz (07~13) 174MHz~216MHz (14~69) 470MHz~806MHz

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(02~06, A-8) by (02~06&01) (07~13) by (07~13) (A~1) by (14~22) (J~W) by (23~36) (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 123W 120V AC, 60Hz -- (54MHz~804MHz) --

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Picture Tube Speaker 27" (68cm) Measured Diagonally Power Consumption High Voltage

················································································································································································································
2" × 4-3/4" / 5 × 12cm Oval type × 2 5W × 2 Video(1,3)

29kV±1.3kV (at zero beam current)

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Video / Audio Input (1 / 2 / 3) : 1Vp-p, 75Ø (RCA pin jack) Audio(1,2,3) : 500mVrms ( -4dBs ), High Impedance (RCA pin jack)

Audio Power Output

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

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Audio Output (Variable) Variable : More then 0~1550mVrms (+6dBs) Low impedance (400Hz when modulated 100%) (RCA pin jack)

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Antenna terminal 75Ø(VHF/UHF) Terminal, F-Type Connector RM-C301G-2A

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Remote Control Unit (AA/R6/UM-3 battery × 2)

Design & specifications are subject to change without notice.

2

No. 51797C

AV-27D502

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 (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. 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. 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.).

·

GOOD EARTH GROUND

AC VOLTMETER (HAVING 1000Ø/V, OR MORE SENSITIVITY) 0.15 µF AC-TYPE PLACE THIS PROBE ON EACH EXPOSED METAL PART

1500Ø 10W

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. POWER CORD REPLACEMENT WARNING Connecting the white line side of power cord to "WHT" character side.
PWB
White line side

A

V
WHT

PW

No. 51797C

3

AV-27D502

FEATURES
· Full-square CRT (cathode ray tube) reproduces fine textured picture in every detail. C control utilizes single · IBuiltbus Twin Tuner system. chip ICs. in · 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. ·
2

· Component input terminal for taking best advantage of Component Video Signal. · Audio Video input terminal. (S-input ×2, V-input ×2) · Variable audio output terminal. be viewed. can · Closed-caption broadcaststerminal. · With AV COMPU LINK EX

a SYSTEM BLOCK DIAGRAM
IC702 EEPROM 4k bit IF2 Remote control unit

SCL 1

SDA 1 AFT2

IC701 MAIN MICON

AFT1

SCL 0

SDA 0

IC301 PIP CONTROL

IC101 1 CHIP CONTROL

TU001 TUNER 1 IC001 MTS, TONE SURROUND CONTROL

TU001 TUNER 2

4

No. 51797C

AV-27D502

MAIN DIFFERENCE LIST
! Model Part name MAIN PWB CRT SOCKET PWB ! PICTURE TUBE AV-27D502/AR SGC-1002A-M2 SGC-3002A-M2 A68ADT25X01 AV-27D502/AS SGC-1001A-M2 SGC-3001A-M2 A68QDN891X001

HOW TO IDENTIFY MODELS
The difference between AV-27D502/AR and AV-27D502/AS is in the PICTURE TUBE. As the result of the difference in PICTURE TUBE, the MAIN PWB also differ. ! Model Part name AV-27D502/AR AV-27D502/AS ! RATING LABEL LC31139-001A-A GQ30032-001A-A -----------------------------------------------------------------------------------------------INDICATED AV-27D502 INDICATED AV-27D502
GQ30032-001A-A

INDICATED "AS"

INDICATED "AR"

No. 51797C

5

AV-27D502

FUNCTIONS
a FRONT PANEL
MENU CHANNEL OPERATE VOLUME POWER ON TIMER

MENU CHANNEL POWER VOLUME

a FRONT PANEL DOOR OPENED

a REMOTE CONTROL UNIT
(RM-C301G-2A)

INPUT3

TV CATV VCR DVD

POWER

VIDEO

L/MONO-AUDIO-R

PIP CHANNEL

ON/MOVE

INPUT3 VIDEO/AUDIO TERMINAL
SOURCE FREEZE SWAP INPUT VIDEO STATUS

1 4 7
100+

2 5 8 0

3 6 9
RETURN+

a REAR PANEL

BBE

DISPLAY

SLEEP TIMER

HYPER SURROUND
RM-C301G

LIGHT

MUTING

V CHIP

+ CH VOL HC
MENU
VCR CHANNEL PREV NEXT

VOL +
EXIT PIP OFF VCR/DVD POWER

TV/VCR

REW

PLAY

FF

REC
OPEN/CLOSE

STOP PAUSE
STILL/PAUSE

TV

6

No. 51797C

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 inserting the MAIN PWB into the rear cover groove.

REMOVING THE SPEAKER
After removing the rear cover. 1. Remove the 4 screws marked H 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 REMOVING THE CHASSIS
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 contacting with other PW Board. Before turning on power, make sure that the CRT earth wire and other connectors are properly connected.

· After removing the rear cover. the chassis by hand and remove the 1. Slightly raise the both sides of
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.

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 TERMINAL BOARD
the rear cover. · After removingscrews marked D as shown in Fig.1. 1. Remove the 4 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 FRONT CONTROL AND FRONT AV INPUT PW BOARDS
the rear cover chassis. · After removingscrews markedand and the 2 screws marked G as 1. Remove the 3 F 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.)

No. 51797C

7

AV-27D502

PICTURE TUBE FRONT CABINET SPEAKER H (x4)

CRT SOCKET PWB FRONT AV INPUT PWB G (x2) CLAW B F (x3) CHASSIS BASE CLAW B H (x4) SPEAKER C REAR COVER E FRONT CONTROL PWB AV SELECTOR PWB PIP PWB MAIN PWB

D (x4) A (x9)

A (x3) Fig.1

8

No. 51797C

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 (1) Power off Switch off the power and disconnect the power cord from the outlet. Screen display

(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.

SERVICE MENU PICTURE THEATER PIP LOW LIGHT RF AFC1 TU2 VCO SELECT BY OPERATE BY SOUND OTHERS HIGH LIGHT RF AFC2 I2C BUS CTRL EXIT BY
EX IT

Fig.1

SYSTEM CONSTANT

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

MODEL CCD V-CHIP CAN V-CHIP

: : : :

99­99999
YES YES YES

999999999 999
(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.
SELECT BY OPERATE BY
EX IT

EXIT BY

Fig.2

(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.

No. 51797C

9

AV-27D502

TABLE 1 (System Constant setting)
Setting item
AV-36230A AV-36D302A

Setting content
AV-27D502A AV-32D302A AV-36D202A AV-36260A AV-32D502A AV-36D502A AV-27260A AV-32260A

Setting value

MODEL

AV-32D202A AV-32230A

AV-27D502A

CCD V-CHIP

YES YES

NO NO

YES YES

CAN V-CHIP

YES

NO

YES

TABLE 2 (User setting value)
Setting item 1. Use remote controller keys POWER CHANNEL VOLUME INPUT HYPER SURROUND BBE DISPLAY SLEEP TIMER VIDEO STATUS PIP SOURCE PIP ON (PIP POSITION) 2. Setting of MENU PICTURE ADJUST TINT COLOR PICTURE BRIGHT DETAIL NOISE MUTING SET VIDEO STATUS SOUND ADJUST BASS TREBLE BALANCE MTS CLOCK/TIMERS SET CLOCK ON/OFF TIMER INITIAL SETUP TV SPEAKER COMPONENT-IN LANGUAGE CLOSED CAPTION AUTO TUNER SETUP CHANNEL SUMMARY V-CHIP SET LOCK CODE OFF CH-02 5 TV OFF ON OFF 0 CHOICE CH-04 LEFT LOWER SIDE Setting value

CENTER CENTER CENTER CENTER CENTER ON ALL CENTER

CENTER CENTER CENTER STEREO

Unnecessary to set NO

ON NO ENG OFF TUNER MODE: AIR Unnecessary to set OFF Unnecessary to set

10

No. 51797C

AV-27D502

REPLACEMENT OF CHIP COMPONENT
a CAUTIONS
1. 2. 3. 4. Avoid heating for more than 3 seconds. Do not rub the electrodes and the resist parts of the pattern. When removing a chip part, melt the solder adequately. Do not reuse a chip part after removing it.

a SOLDERING IRON
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.

a REPLACEMENT STEPS
1. How to remove Chip parts
Resistors, capacitors, etc. (1) As shown in the figure, push the part with tweezers and alternately 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) 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. (2) Shift with tweezers and remove the chip part.

Transistors, diodes, variable resistors, etc. (1) Apply extra solder to each lead.

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.

SOLDER

SOLDER

A B
(2) As shown in the figure, push the part with tweezers and alternately melt the solder at each lead. Shift and remove the chip part.

C
(4) Then solder leads B and C.
A B C

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

No. 51797C

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 HYPER SURROUND BASS, TREBLE, BALANCE TINT, COLOR, PICTURE, BRIGHT, DETAIL STANDARD OFF CENTER CENTER

MEASURING INSTRUMENT
1. 2. 3. 4. 5. 6. 7. DC voltmeter(or digital voltmeter) Oscilloscope Signal generator ( Pattern generator ) [NTSC] Remote control unit TV audio multiplex signal generator Frequency counter Resistor (1MØ)

ADJUSTMENT ITEMS

· Check of B1 POWER SUPPLY · RF AGC adjustment · TU2 VCO adjustment · FOCUS adjustment · WHITE BALANCE adjustment · · · ·

· MTS circuit 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 POSITION and V SIZE adjustment H POSITION adjustment PIP DISPLAY POSITION adjustment CHROMA adjustment SUB COLOR adjustment SUB TINT adjustment

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

12

No. 51797C

AV-27D502

ADJUSTMENT LOCATIONS
FRONT CONTROL PWB
POWER VOL CH MENU

FRONT AV INPUT PWB

FRONT
006 007

FRONT

MAIN PWB
CN007 IC702 SS IC701 CPU DEG

FRONT

PW

F901 125V 5A

CN004

CN001

Q511 Heatsink

CN002

B1 HV S421

J601 S1 CN005 E1

TU001

TU001

AV SELECTOR PWB
FRONT TOP

UPPER : FOCUS LOWER : SCREEN

CN006

CRT SOCKET PWB PIP PWB
FRONT TOP
TP-R TP-B TP-G

TOP

MPX

CN001 T111

CN002

CN004 TP-E E2 CN005

TU001 J501 J502 J503

(SOLDER SIDE)

No. 51797C

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 adjusted. 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] TU2 VCO ................................ This is used when the TU2 VCO MODE is adjusted. 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 TU2 VCO

· · · · ·

SOUND OTHERS HIGH LIGHT RF AFC2 I2C BUS CTRL

(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, TU2 VCO and I2C BUS CTRL mode 1) If select any of THEATER / LOW LIGHT / HIGH LIGHT / RF AFC1 / RF AFC2 / TU2 VCO / 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.

14

No. 51797C

AV-27D502

1 SERVICE MENU (MAIN MENU)
SERVICE MENU PICTURE THEATER PIP LOW LIGHT RF AFC1 TU2 VCO SELECT BY OPERATE BY SOUND OTHERS HIGH LIGHT RF AFC2 I2C BUS CTRL EXIT BY
EX IT

2 SCREEN

3 PICTURE MODE

SELECT

BY EXIT BY

EX IT

1. BRIGHT STATUS

999 99999999

10 HIGH LIGHT MODE

4 SOUND MODE

5 OTHERS MODE

HIGH LIGHT

999

999

1. NOISE DET. STATUS

999 99999999

1. OSD POS.

999

11 RF AFC1 MODE

[DO NOT ADJUST]

6 SCREEN

7 PIP MODE

TOO HIGH RF AFC1 FINE SELECT BY OPERATE BY

GOOD

TOO LOW

999
EXIT BY
EX IT

ON

SELECT

BY EXIT BY

EX IT

1. PIP BR STATUS

999 99999999

12 RF AFC2 MODE

[DO NOT ADJUST]

TOO HIGH RF AFC2 FINE SELECT BY OPERATE BY

GOOD

TOO LOW

999
EXIT BY
EX IT

ON

13 TU2 VCO MODE
TU2 VCO

8 THEATER MODE (1/2)
TINT COLOR PICTURE BRIGHT DETAIL R CUT. G CUT.

THEATER MODE (2/2)
CD MAT. RY GAIN GY PHASE CORING

HIGH LEVEL REFERENCE LEVEL LOW LEVEL SYNC : YES

999 999 999 999 999 999 999

B CUT. R DRIVE B DRIVE DC REST. BLK ST. GMM PNT

999 999 999 999 999 999

99 99 99 99

CMP CD M CMP RY G CMP GY P CMP COR

99 99 99 99

PAGE 1/2 SELECT BY OPERATE BY EXIT BY
EX IT

PAGE 2/2 SELECT BY OPERATE BY EXIT BY
EX IT

14 I2C BUS CTRL MODE

[FIXED ON]

9 LOW LIGHT MODE

I2C BUS SELECT BY OPERATE BY

ON
EX IT

BRIGHT

EXIT BY

999

999 999

999

No. 51797C

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.

SETTING ITEM

1. BRIGHT STATUS

999 99999999
PICTURE MODE

INITIAL SETTING VALUE (Adjust) SETTING VALUE

(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 BALANCE page of ADJUSTMENT.

16

No. 51797C

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. Initial setting value AV-27D502/AR 063 080 072 065 055 ±000 ±006 ­006 ±000 050 ±000 +006 086 064 050 ­011 ±000 ­001 ±000 ±000 001 000 000 000 001 001 001 001 031 000 001 000 000 127 008 074 AV-27D502/AS

No. 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 BRIGHT PICTURE COLOR TINT TV DETAIL EXT BRIGHT EXT PICT. EXT COLOR EXT TINT EXT DETAIL CMP BRIGHT CMP PICT. CMP COLOR CMP TINT CMP DETAIL CMP R CUT CMP G CUT CMP B CUT CMP R DRV CMP B DRV WPL B. B. SW C TRAP CORING CMP CORING TV SHARPF EXT SHARPF CMP SHARPF RGB CONT TV ID SENS EXT ID SEN F ID Y MUTE AUDIO ATT SUB CONT

Setting (Adjustment) item

Variable range 000 -- 127 000 -- 127 000 -- 127 000 -- 127 000 -- 063 ±025 ±025 ±025 ±025 000 -- 063 ±025 ±025 000 -- 127 000 -- 127 000 -- 063 ±025 ±025 ±025 ±025 ±025 000 / 001 000 / 001 000 / 001 000 / 001 000 / 001 000 / 001 000 / 001 000 / 001 000 -- 063 000 / 001 000 / 001 000 / 001 000 / 001 000 -- 127 000 -- 015

No. 51797C

17

AV-27D502

No. 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65 66 67 68 69 70 71 72 73 74 75 76 77 78 79 80 81 82 R Y GAIN CMP R Y GA G Y PHASE CMP G Y PH CD MATRIX CMP CD MAT BLACK ST DC REST COLOR GMM UV/CBCR AT FLESH ABL GAIN ABL ST PNT RGB ABCL TV BPF TOF EXT BPF TOF GMM PNT SVM GAIN CMP SVM GA SVM PHASE AUDIO SW BUZZ IF FREQ RF AGC AFT MUTE AFT SENS R/G DRV SW BLK SW V S COR V LIN V SIZE V AGC V CENTER TV AFC EXT AFC V POSI H POSI H SIZE TV V FREQ EXT V FREQ SIDE PIN STAND BY TRAPEZ V RAMP REF V 48HZ V EHT TOP PIN

Setting (Adjustment) item

Variable range 000 / 001 000 / 001 000 / 001 000 / 001 000 -- 003 000 -- 003 000 -- 003 000 -- 003 000 / 001 000 / 001 000 / 001 000 -- 003 000 -- 003 000 / 001 000 / 001 000 / 001 000 -- 003 000 -- 003 000 -- 003 000 / 001 000 / 001 000 / 001 000 / 001 000 -- 063 000 / 001 000 / 001 000 / 001 000 / 001 000 -- 015 000 -- 015 000 -- 127 000 / 001 000 -- 063 000 -- 003 000 -- 003 000 -- 007 000 -- 031 000 -- 063 000 -- 003 000 -- 003 000 -- 063 000 / 001 000 -- 063 000 / 001 000 / 001 000 -- 007 000 -- 031

Initial setting value AV-27D502/AR 001 001 000 000 003 002 001 001 000 001 000 000 003 001 001 000 003 003 003 000 000 000 000 045 000 001 001 000 011 010 056 000 000 000 002 000 021 000 000 003 000 000 000 001 000 000 010 022 065 AV-27D502/AS

18

No. 51797C

AV-27D502

No. 83 84 85 86 87 88 89 90 91 92 93 94 95 96 97 98 99 100 101 102 103 104 105 106 107 108 109 110 111 112 113 114 115 116 117 118 119 120 121 122 123 124 125 126 127 128 129 H EHT BTM PIN V BLK LOW V BLK UP CAPTION IN H BLK SCREEN ACB SW ACB PULSE OVER MODU APACON LIM TEST RF S/N TY EXT S/N TY RF SN YC E RF SN YC F RF SN YC G RF SN YC H EX SN YC E EX SN YC F EX SN YC G EX SN YC H RF SN VC 1 RF SN VC 2 RF SN VC 3 RF SN VC 4 EX SN VC 1 EX SN VC 2 EX SN VC 3 EX SN VC 4 COR LEVEL VNR CHK YC SN TIME VC SN TIME VM DATA A VM DATA B VM DATA C VM DATA D VC SN STOP CH MUTE VM OFF TY VC VM OFF YC VM OFF F LOCK VF LOCK EX PURI RGB PURI W BCK

Setting (Adjustment) item

Variable range 000 -- 007 000 -- 031 000 -- 003 000 -- 003 000 / 001 000 / 001 000 / 001 000 / 001 000 -- 015 000 / 001 000 / 001 000 -- 255 000 -- 002 000 -- 002 000 -- 255 000 -- 255 000 -- 063 000 -- 255 000 -- 255 000 -- 255 000 -- 063 000 -- 255 000 -- 063 000 -- 063 000 -- 063 000 -- 063 000 -- 063 000 -- 063 000 -- 063 000 -- 063 000 -- 003 000 -- 255 000 -- 255 000 -- 255 ±127 ±127 ±127 000 / 001 000 -- 255 000/001 000/001 000/001 000 -- 255 000 -- 002 000/001 000 -- 063 000/001

Initial setting value AV-27D502/AR 000 000 000 000 000 000 000 000 007 001 001 128 002 002 005 016 032 025 005 016 032 025 000 007 014 021 000 007 014 021 003 003 005 005 +008 ­004 ­016 000 002 000 000 001 255 002 000 031 000 AV-27D502/AS

No. 51797C

19

AV-27D502

· SOUND MODE
No. 1 2 3 4 5 6 7 8 9 10 11 12 13 14 NOISE DET. IN LEVEL FH MONITOR STEREO VCO PILOT CAN. FILTER LOW SEP. HI SEP. 5FH MON. SAP VCO IN GAIN FIL. OFFSET BBE BASS BBE TRE Setting (Adjustment) item Variable range 000 / 001 000 -- 063 000 / 001 000 -- 063 000 / 001 000 -- 063 000 -- 063 000 -- 063 000 / 001 000 -- 063 000 / 001 ±010 ±010 ±010 Initial setting value AV-27D502/AR 001 025 000 030 000 030 028 025 000 003 000 ±000 +003 +003 AV-27D502/AS

· THEATER MODE
Setting (Adjustment) item TINT COLOR PICTURE BRIGHT DETAIL R CUT. G CUT. B CUT. R DRIVE B DRIVE DC REST. BLK ST. GMM PNT CD MAT. RY GAIN GY PHASE CORING CMP CD M CMP RY G CMP GY P CMP COR Variable range ±20 ±20 ±50 ±20 ±20 ±20 ±20 ±20 ±99 ±99 00 -- 03 00 -- 03 00 -- 03 00 -- 03 00 / 01 00 / 01 00 / 01 00 -- 03 00 / 01 00 / 01 00 / 01 Initial setting value AV-27D502/AR ­06 ­03 ­15 ±00 +03 ±00 ±00 ±00 +07 ­25 01 00 01 01 01 00 01 01 01 00 01 AV-27D502/AS

20

No. 51797C

AV-27D502

· OTHERS MODE
No. 1 2 3 4 5 6 OSD POS. CCD POS. EOSEL MENU COLOR MENU PICT. MENU BRI. Setting (Adjustment) item Variable range 000 -- 007 000 -- 015 000 / 001 000 -- ­030 000 -- ­030 000 -- ­030 Initial setting value AV-27D502/AR 002 003 000 ­010 ­010 ­010 AV-27D502/AS

· PIP MODE
No. 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 PIP BR PIP PICT PIP TINT PIP COL P R CUT P G CUT P B CUT P R DR P G DR P B DR LEFT POS. RIGHT POS. UPPER POS. LOWER POS. PICT LOCK SELDEL AGCFIX AGCADST AGC VSPDEL VSPISQ YCOR XFREQF WTCHDG COLON ACQNEW DSTDET CRIBEOK FCBEOK NOCRID NONSED Setting (Adjustment) item Variable range 000 -- 015 030 -- 045 000 -- 063 000 -- 015 000 -- 015 000 -- 015 000 -- 015 000 -- 255 000 -- 255 000 -- 255 000 -- 255 000 -- 255 000 -- 127 000 -- 127 000 / 001 000 -- 015 000 / 001 000 / 001 000 -- 015 000 -- 031 000 / 001 000 / 001 000 / 001 000 / 001 000 / 001 000 / 001 000 / 001 000 / 001 000 / 001 000 / 001 000 / 001 Initial setting value AV-27D502/AR 004 045 036 010 003 000 002 052 055 060 020 017 012 011 001 000 001 000 007 000 001 001 001 001 000 000 001 000 000 000 000 042 AV-27D502/AS

No. 51797C

21

AV-27D502

· LOW LIGHT MODE
Setting (Adjustment) item R CUTOFF G CUTOFF B CUTOFF Variable range 0 -- 255 0 -- 255 0 -- 255 Initial setting value 085 085 085

· HIGH LIGHT MODE
Setting (Adjustment) item R DRIVE B DRIVE Variable range 0 -- 127 0 -- 127 Initial setting value 060 060

· RF AFC1 MODE
Setting (Adjustment) item RF AFC1 FINE Variable range ON / OFF -77 -- +77 Initial setting value ON ±×× DO NOT ADJUST

· RF AFC2 MODE
Setting (Adjustment) item RF AFC2 FINE Variable range ON / OFF -77 -- +77 Initial setting value ON ±×× DO NOT ADJUST

· I2C BUS CTRL MODE
Setting (Adjustment) item I2C BUS Variable range ON/OFF Initial setting value [FIXED ON] DO NOT ADJUST

22

No. 51797C

AV-27D502

ADJUSTMENTS
B1 POWER SUPPLY
Item Check of B1 POWER SUPPLY Measuring instrument Test point Adjustment part Description 1. Receive a black-and-white signal. 2. Connect the DC Voltmeter between B1 and GND (between pin 1 and 3 of the B1 connector). 3. Confirm that the voltage is DC134V +2V . -2V

DC Voltmeter B1 (pin 1) GND (pin 3) [B1 connector in MAIN PWB]

ADJUSTMENT OF RF AGC
Item RF AGC adjustment Measuring instrument Remote control unit Test point Adjustment part 1. 2. 3. 4. Description Receive a broadcast. Select the No.59 RF AGC of the PICTURE MODE. Press the MUTE key of the remote control unit to turn off color. 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.

ADJUSTMENT OF TU2 VCO
Item TU2 VCO adjustment Measuring instrument Remote control unit
TU2 VCO

Test point

Adjustment part T111 (CW TRANSF) [PIP PWB] 1. 2. 3. 4.

Description Receive a broadcast. Select the TU2 VCO MODE from the SERVICE MENU. Confirm "SYNC" is "YES". Turn the T111 (CW TRANSF) until "REFERENCE LEVEL" characters become yellow. 5. Confirm "SYNC" is "YES" again.

HIGH LEVEL REFERENCE LEVEL LOW LEVEL SYNC : YES

YELLOW

ADJUSTMENT OF FOCUS
Item FOCUS adjustment Measuring instrument Signal generator Test point Adjustment part FOCUS VR [In HVT] H VR [In HVT] Description 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. 51797C

23

AV-27D502

ADJUSTMENT OF WHITE BALANCE
Item WHITE BALANCE (Low Light) adjustment Measuring instrument Signal generator Remote control unit Test point Adjustment part No.1 BRIGHT R CUTOFF G CUTOFF B CUTOFF SCREEN VR [In HVT] Description 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.

[LOW LIGHT] MODE

BRIGHT

999
R CUTOFF

999 999
G CUTOFF

999

BRIGHT B CUTOFF

REMOTE CONTROL UNIT
H.LINE ON H.LINE OFF EXIT

1
R CUTOFF

2
G CUTOFF

3
B CUTOFF

9

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

4
R CUTOFF

5
G CUTOFF

6
B CUTOFF

7

8

9

WHITE BALANCE (High Light) adjustment

Signal generator Remote control unit
[HIGH LIGHT] MODE

R 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
HIGHT LIGHT

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

999
R DRIVE

999

B DRIVE

REMOTE CONTROL UNIT
H.LINE ON H.LINE OFF EXIT

1
R DRIVE

2 5 8

3
B DRIVE

4
R DRIVE

6
B DRIVE

7

9

24

No. 51797C

AV-27D502

Item PIP HIGH LIGHT WHITE BALANCE adjustment

Measuring instrument Signal generator Remote control unit

Test point

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

Description 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.

PIP screen

Main screen

ADJUSTMENT OF BRIGHT
Item SUB BRIGHT adjustment Measuring instrument Remote control unit Test point Adjustment part No.1 BRIGHT Description Notes: · 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". 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.

ADJUSTMENT OF CONTRAST
Item SUB CONTRAST adjustment Measuring instrument Remote control unit Test point Adjustment part No.2 PICTURE Description 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. 51797C

25

AV-27D502

ADJUSTMENT OF DEFLECTION
Item V POSITION and V SIZE adjustment Measuring instrument Signal generator Remote control unit Test point Adjustment part No.71 V POSI No.66 V SIZE Description Note: Proceed to the following this adjustment after having completed the adjustments of SUB BRIGHT and SUB CONTRAST.

S1421(V CENTER SW) [MAIN PWB] 1. Receive a crosshatch signal with circle pattern. 2. Select the No.71 V POSI of the PICTURE MODE.

Screen size

3. Confirm the value of No.71 V POSI is "0". 4. Switch the S1421 (V CENTER SW) so that a crosshatch signal become to the center of CRT. 5. Select the No.66 V SIZE of the PICTURE MODE to squeeze the raster.

Screen size 90%

Picture size 100%

6. Adjust the No.66 V SIZE untill the vertical screen size is 90%.

Picture size 100%

H POSITION adjustment

Signal generator Remote control unit

No.72 H POSI

Note: Proceed to the following this adjustment after having completed the adjustments of FOCUS, SUB BRIGHT, SUB CONTRAST, V POSITION and V SIZE. 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.

PIP DISPLAY POSITION adjustment

Remote control unit

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

Notes: · Proceed to the following this adjustment after having completed the adjustments of V POSITION, V SIZE 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.

LEFT POS. UPPER POS.

RIGHT POS.

80% ±2%

Main screen size

LOWER POS. 80% ±2% Main screen size

26

No. 51797C

AV-27D502

ADJUSTMENT OF CHROMA
Item SUB COLOR adjustment Measuring instrument Signal generator Test point Adjustment part Description 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.
R

No.3 COLOR TP-B TP-E( ) [CRT SOCKET Oscilloscope PWB] Remote control unit

Y

G

(A) W
Cy Mg

B

(­) 0V (+)

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.

Model AV-27D502/AR AV-27D502/AS

A (Vw-B) +7V +6V

Table 1

SUB TINT adjustment

No.4 TINT TP-B ) TP-E( [CRT SOCKET Oscilloscope PWB] Signal generator Remote control unit

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 adjustment 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 voltage shown in the table 2.

Y

G

R

W

Cy

(­) 0V (+)

Mg

B

(B)

Model AV-27D502/AR AV-27D502/AS

B (Vw-Mg) +13V +9V

Table 2

No. 51797C

27

AV-27D502

ADJUSTMENT OF MTS CIRCUIT
Item MTS INPUT LEVEL check MTS STEREO VCO adjustment Measuring instrument Remote control unit Test point Adjustment part No.2 IN LEVEL Description 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.

Signal generator Frequency counter Remote control unit

2 pin AUDIO R No.3 FH MONITOR No.4 STEREO VCO 3 pin GND [MPX Connector in AV SELECTOR PWB]

Note: Menu "MTS" is set to "STEREO" 1. Receive a RF signal (non modulated 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. 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 generator to the antenna terminal. 2. Connect an oscilloscope to pin 1 of [MPX] connector, and display one cycle portion of the 300Hz signal. 3. Change the connection of the oscilloscope to pin 2 of [MPX] connector, and enlarge the voltage axis. 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/ RIGHT key of the remote control unit. 6. Adjust the No.7 LOW SEP. so that the 300Hz signal level will become minimum. 7. Change the signal to 3kHz, and connect an oscilloscope to pin 1 of [MPX] connector. 8. Adjust the No.8 HI SEP. so that the 3kHz signal level will become minimum.

MTS SAP VCO adjustment

Signal generator Frequency counter Remote control unit

4 pin TP_952.5 No.9 5FH MON. No.10 SAP VCO 3 pin GND 2 pin AUDIO_R [MPX Connector in AV SELECTOR PWB]

MTS FILTER check MTS SEPARATION adjustment

Remote control unit TV audio multiplex signal generator Remote control unit Oscilloscope

No.6 FILTER

1 pin AUDIO_L No.7 LOW SEP. 2 pin AUDIO_R No.8 HI SEP. 3 pin GND [MPX Connector in AV SELECTOR PWB]

L-Channel signal waveform

R-Channel crosstalk portion Minimum

1 cycle

28

No. 51797C

AV-27D502

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

RY951 RESISTOR 24.7 k ± 123.5

R952 R951 POWER ON OFF R532 R533 D535 Q531

Q951

HEATER

3 1
Q532

S1

CONNECTOR

T502 R534 + R538 C533 R535 BW D534 D531

R537 +

FR525 4 D525 C525

Fig. 1

No. 51797C

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 Over-current protector Details of detection Operation of B1 protector circuit. Method of detection The microcomputer detects at 1 second intervals. If NG is detected for more than 200 ms, a malfunction is interpreted. State of malfunction 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.

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.
POWER Supplied After about 5 seconds Malfunction is detected

Start of detection

POWER OFF Flashing ON-TIMER LED

[ON-TIMER LED indication] The ON-TIMER LED flashes at 0.5 seconds intervals.

30

No. 51797C

JVC SERVICE & ENGINEERING COMPANY OF AMERICA DIVISION OF JVC AMERICAS CORP.
Head office : East Coast : Midwest : West Coast : Southwest : Hawaii : Southeast :
1700 Valley Road, Wayne, New Jersey 07470 10 New Maple Avenue, Pine Brook, New Jersey 07058 705 Enterprise St. Aurora, Illinois 60504 5665 Corporate Avenue, Cypress, California 90630 10700 Hammerly, Suite 105, Houston, Texas 77043 2969 Mapunapuna Place, Honolulu, Hawaii 96819 1500 Lakes Parkway, Lawrenceville, Georgia 30243 (973)317-5000 (973)396-1000 (630)851-7855 (714)229-8011 (713)935-9331 (808)833-5828 (770)339-2582

JVC CANADA INC.
Head office : Vancouver : 21 Finchdene Square Scarborough, Ontario M1X 1A7 13040 Worster Court Richmond B.C. V6V 2B3 (416)293-1311 (604)270-1311

®

AV27D502AR-UCM #4 AV27D502AS-UCM #4

Printed in Japan VP0112 SW