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AV-27230

SERVICE MANUAL
COLOR TELEVISION

AV-27230/S AV-27230/R

BASIC CHASSIS

FD

CONTENTS
SPECIFICATIONS 2 SAFETY PRECAUTIONS 3 4 FEATURES MAIN DIFFERENCE LIST 4 HOW TO IDENTIFY MODELS 4 5 FUNCTIONS SPECIFIC SERVICE INSTRUCTIONS 6 SERVICE ADJUSTMENTS 10 PARTS LIST 29 OPERATING INSTRUCTIONS 1-1 STANDARD CIRCUIT DIAGRAM 2-1 ! ! ! ! ! ! ! ! !

1

COPYRIGHT © 2001 VICTOR COMPANY OF JAPAN, LTD.

No.51803 Apr. 2001 Apr. 2001

AV-27230

SPECIFICATIONS
Contents Items

AV-27230/S AV-27230/R
25-3/4"×23-3/8"×19-1/2" / 654mm×593mm×494mm 68.5 Ibs / 31.1 kg NTSC, BTSC System (Multi-Channel Sound)

Dimensions (W×H×D) × × Mass Reception Format Reception Range VHF, UHF VL Band VH Band UHF Band CATV 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 Input terminal Input 1

(0206) 54MHz88MHz (0713) 174MHz216MHz (1469) 470MHz806MHz (0206, A-8) by (0206&01) (0713) by (0713) (A1) by (1422) (JW) by (2336) (W+1W+28) by (3764) (W+29W+84) by (65125) (A8, A4A1) by (01, 9699) 181 Channels 45.75MHz 41.25MHz (4.5MHz) 3.58MHz 120V AC, 60Hz 113W 27" (68cm) Measured Diagonally 29kV±1kV (at zero beam current) 2"×3-1/2" / 5×9cm Oval type×2 1.2W + 1.2W

(54MHz804MHz)

S-Video Video(V) Audio(L, R)

Y: 1Vp-p Positive (negative sync provided, when terminated with 75) C: 0.286Vp-p (burst signal, when terminated with 75) 1Vp-p, 75 (RCA pin jack) 500mVrms ( -4dBs ), High Impedance (RCA pin jack)

Input 2

Component Video Y, Pb, Pr

1Vp-p 75(positive sync)

Input 3 (Front)

Video(V) Audio(L, R)

1Vp-p, 75 (RCA pin jack) 500mVrms ( -4dBs ), High Impedance (RCA pin jack)

Output terminal Variable Audio Output (R/L) Antenna terminal Remote Control Unit

More than 01550mVrms (+6dBs) Low impedance (400Hz when modulated 100%) (RCA pin jack) 75(VHF/UHF) Terminal, F-Type Connector RM-C306-1A (AA/R6/UM-3 battery×2)

Design & specifications are subject to change without notice.
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AV-27230

SAFETY PRECAUTIONS
1. The design of this product contains special hardware, many circuits and components specially for safety purposes. For continued protection, no changes should be made to the original design unless authorized in writing by the manufacturer. Replacement parts must be identical to those used in the original circuits. Service should be performed by qualified personnel only. 2. Alterations of the design or circuitry of the products should not be made. Any design alterations or additions will void the manufacturer's warranty and will further relieve the manufacturer of responsibility for personal injury or property damage resulting therefrom. 3. Many electrical and mechanical parts in the products have special safety-related characteristics. These characteristics are often not evident from visual inspection nor can the protection afforded 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 with a measuring apparatus (oscilloscope etc.) the LIVE side GND and ISOLATED(NEUTRAL) side GND or EARTH side GND at the same time. If above note will not be kept, a fuse or any parts will be broken. 6. If any repair has been made to the chassis, it is recommended that the B1 setting should be checked or adjusted (See ADJUSTMENT OF B1 POWER SUPPLY). 7. The high voltage applied to the picture tube must conform with that specified in Service manual. Excessive high voltage can cause an increase in X-Ray emission, arcing and possible component damage, therefore operation under excessive high voltage conditions should be kept to a minimum, or should be prevented. If severe arcing occurs, remove the AC power immediately and determine the cause by visual inspection (incorrect installation, cracked or melted high voltage harness, poor soldering, etc.). To maintain the proper minimum level of soft X-Ray emission, components in the high voltage circuitry including the picture tube must be the exact replacements or alternatives approved by the manufacturer of the complete product. 8. Do not check high voltage by drawing an arc. Use a high voltage meter or a high voltage probe with a VTVM. Discharge the picture tube before attempting meter connection, by connecting a clip lead to the ground frame and connecting the other end of the lead through a 10k 2W resistor to the anode button. 9. When service is required, observe the original lead dress. Extra precaution should be given to assure correct lead dress in the high voltage circuit area. Where a short circuit has occurred, those components that indicate evidence 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 1500 10W resistor paralleled by a 0.15F AC-type capacitor between an exposed metal part and a known good earth ground (water pipe, etc.). Measure the AC voltage across the resistor with the AC voltmeter. Move the resistor connection to each exposed metal part, particularly any exposed metal part having a return path to the chassis, and measure the AC voltage across the resistor. Now, reverse the plug in the AC outlet and repeat each measurement. Any voltage measured must not exceed 0.75V AC (r.m.s.). This corresponds to 0.5mA AC (r.m.s.). However, in tropical area, this must not exceed 0.3V AC (r.m.s.). This corresponds to 0.2mA AC (r.m.s.).
AC VOLTMETER /V, (HAVING 1000 OR MORE SENSITIVITY) 0.15F AC-TYPE PLACE THIS PROBE ON EACH EXPOSED METAL PART

GOOD EARTH GROUND

1500 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.

A

V

No. 51803

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AV-27230

FEATURES
" New
chassis design enables use of a single board with simplified circuitry. the component video signal input terminal.

" Users can make fun to connect the Digital Video Disk player with " Provided with miniature tuner (TV/CATV). " Multifunctional remote control permits picture adjustment. " Adoption of the CHANNEL GUARD function prevents " I2C bus control utilizes single chip ICs. " Adoption of the VIDEO STATUS function. " Adoption of the ON/OFF TIMER function.

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

" Built-in V-CHIP system. " With 75V/U in common (F-Type) ANT Terminal. " SLEEP TIMER for setting in real time. " Closed-caption broadcasts can be viewed. " Built-in MTS system. " Built-in HYPER-SURROUND system. " S-VIDEO input terminal for taking best advantage of Super VHS. " Variable Audio output terminal. " 2 LINE Digital Comb filter Improved picture quality.

MAIN DIFFERENCE LIST
Model name ! Parts Name MAIN PWB ! ITC TUBE SFD-1003A-M2 A68QDN891X001 SFD-1004A-M2 A68ADT25X01

AV-27230/S

AV-27230/R

HOW TO IDENTIFY MODELS
The difference between AV-27230/S and AV-27230/R is in the PICTURE TUBE. As the result of the difference in picture tube, the MAIN PWB also differs.

!
Parts name

MODEL AV-27230/S RATING LABEL LC31139-001A-A Indicated AV-27230 AV-27230/R

!


Indicated AV-27230

Indicated "S"

Indicated "R"

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No.51803

AV-27230

FUNCTIONS
FRONT PANEL CONTROL REAR TERMINAL















VIDEO INPUT TERMINAL AUDIO L INPUT TERMINAL AUDIO R INPUT TERMINAL MENU KEY CHANNEL -/+ KEY (OPERATE KEY) VOLUME -/+ KEY POWER LED ON TIMER LED REMOCON WINDOW







AUDIO OUTPUT TERMINAL INPUT1 TERMINAL(S, V, L, R) INPUT2 TERMINAL(V/Y, PR, PB, L, R) AERIAL SOCKET

REMOTE CONTROL UNIT [RM-C306]









TV / CATV VIDEO STATUS DISPLAY SLEEP TIMER HYPER SURROUND MUTING MENU POWER VCR / DVD INPUT CHANNEL KEYS V-CHIP EXIT VCR CONTROL KEYS



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AV-27230

SPECIFIC SERVICE INSTRUCTIONS
DISASSEMBLY PROCEDURE
REMOVING THE REAR COVER
1. Disconnect the power plug from wall outlet. 2. As shown in the Fig.1, remove the 7 screws marked !. 3. As shown in Fig.1, remove the 4 screws marked ". 4. Then remove the REAR COVER toward you.

CHECKING THE PW BOARD
To check the PW Board from back side. 1. Pull out the chassis (refer to REMOVING THE MAIN PWB). 2. Erect the chassis vertically so that you can easily check the back side of the PW Board.

REMOVING THE MAIN PWB
" After removing the REAR COVER. 1. Slightly raise the both sides of the Main PWB by hand and remove the Main PWB from the front cabinet. 2. Withdraw the chassis backward. (If necessary, remove the wire clamp, connectors etc.)

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 wire connector is properly connected. " When conducting a check with power supplied, be sure to confirm that the CRT EARTH WIRE (BRAIDED ASS' Y) is ' connected to the CRT SOCKET PW board.

REMOVING THE SPEAKER
" After removing the rear cover. 1. As shown in Fig. 1, removing the

2 screws marked #, then

WIRE CLAMPING AND CABLE TYING
1. Be sure to clamp the wire. 2. Never remove the cable tie used for tying the wires together. Should it be inadvertently removed, be sure to tie the wires with a new cable tie.

remove the speaker. 2. Follow the same steps when removing the other hand speaker.

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No.51803

AV-27230

FRONT CABINET

CRT

CRT SOCKET PWB SPEAKER

MAIN PWB

#

HVT

POWER PWB

SPEAKER

#

REAR COVER

" !
POWER CORD

Fig.1 No.51803 7

AV-27230

MEMORY IC REPLACEMENT
1. Memory IC
This model uses 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 UP/DOWN (/) key and adjust the setting with the LEFT/RIGHT ( ) keys. 5) After adjusting, release the LEFT/RIGHT( ) key to store the setting value. 6) Press the EXIT key twice to return the normal screen.

SERVICE MENU PICTURE THEATER LOW LIGHT RF AFC CHK SELECT BY OPERATE BY SOUND HIGH LIGHT EXIT BY EXIT

Fig.1

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

SYSTEM CONSTANT MODEL V-CHIP CAN V-CHIP : : : **-* **- * **** YES YES

******** *** **** *** * ****-**** *

(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

EXIT BY EXIT

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.

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No.51803

AV-27230

TABLE 1 (System Constant setting)
Setting value Setting item Setting content AV-27D302 MODEL AV-27230 V-CHIP YES YES AV-20D202 NO NO YES YES AV-27D202 AV-27230 AV-27230

AV-27230/S

AV-27230/R

CAN V-CHIP

YES

YES

TABLE 2

(User setting value)
Setting item Setting value

1. Use remote controller keys POWER CHANNEL CHANNEL PRESET VOLUME TV/VIDEO(INPUT) DISPLAY SLEEP TIMER VIDEO STATUS HYPER SURROUND 2. Setting of MENU TINT COLOR PICTURE BRIGHT DETAIL NOISE MUTING SET VIDEO STATUS BASS TREBLE BALANCE MTS TV SPEAKER SET CLOCK ON/OFF TIMER LANGUAGE CLOSED CAPTION BACKGROUND V2 COMPONENT IN AUTO TUNER SETUP CHANNEL SUMMARY V-CHIP V-CHIP RATINGS SET LOCK CODE UNRATED CENTER CENTER CENTER CENTER CENTER ON ALL CENTER CENTER CENTER CENTER STEREO ON Unnecessary to set NO ENGLISH OFF BLACK NO TUNER MODE : AIR Unnecessary to set OFF ALL OFF Unnecessary to set VIEW ON CH 02 See OPERATING INSTRUCTIONS. 10 TV OFF OFF STANDARD OFF

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AV-27230

SERVICE ADJUSTMENTS
ADJUSTMENT PREPARATION
1. You can make the necessary adjustments for this unit with either the Remote Control Unit or with the adjustment tools 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 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, condensers, etc. 7. Presetting before adjustment. Unless otherwise specified in the adjustment instructions, preset the following functions with the remote control unit:

VIDEO STATUS BASS, TREBLE, BALANCE HYPER SURROUND TINT, COLOR, PICTURE, BRIGHT, DETAIL

STANDARD CENTER OFF CENTER

ADJUSTMENT EQUIPMENT
1. DC voltmeter (or digital voltmeter) 2. Oscilloscope 3. 4. 5. 6. Signal generator (Pattern generator)NTSC Remote control unit TV audio multiplex signal generator. Frequency counter

ADJUSTMENT ITEMS
Adjustment items B1 POWER SUPPLY RF. AGC FOCUS V. SIZE H. POSITION WHITE BALANCE (Low Light) Adjustment items WHITE BALANCE (High Light) SUB BRIGHT SUB CONTRAST SUB COLOR SUB TINT MTS INPUT LEVEL check Adjustment items MTS STEREO VCO MTS SAP VCO MTS FILTER check MTS SEPARATION

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No.51803

AV-27230

ADJUSTMENT LOCATIONS
TOP FRONT

CRT SOCKET PWB
(Within MAIN PWB ASS'Y)
TP-R

POWER PWB

A

T CRT EARTH (BRAIDED ASS'Y) E1 PW

P

TP-E (SOLDER SIDE) FUSE

FRONT

MAIN PWB
VOL+ VOLCH+ CHMENU POWER POWER

A

IC701

IC702

S

RESISTER
T

FUSE

TP-91 (B1)

IC101
U HV

TP-E ( )

TUNER

HVT

IC921

AV IN / OUT

UPPER : FOCUS LOWER : SCREEN

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AV-27230

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 SOUND THEATER LOW LIGHT HIGH LIGHT RF AFC CHK This sets the setting values (adjustment values) of the VIDEO/CHROMA and DEFLECTION circuits. This sets the setting values (adjustment values) of the AUDIO circuit. This is used when the THEATER MODE is adjusted. This sets the setting values (adjustment values) of the WHITE BALANCE circuit. This sets the setting values (adjustment values) of the WHITE BALANCE circuit. This is used when the IF VCO is adjusted. [Do not adjust]

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 shown in the next figure page. (2) SERVICE MENU screen selection Press the UP / DOWN(/) key to select any of the following items.


PICTURE THEATER LOW LIGHT RF AFC CHK



SOUND HIGH LIGHT



(3) Enter the any setting ( adjustment ) mode " PICTURE and SOUND mode 1) If select any of PICTURE or SOUND items, and the LEFT / RIGHT( screen will be displayed as shown in figure page later.

) key is pressed from SERVICE MENU ( MAIN MENU ), the

2) Then the UP / DOWN(/) key is pressed, the PICTURE mode screen or the SOUND mode screen is displayed, and the PICTURE or SOUND setting can be performed. " THEATER, LOW LIGHT, HIGH LIGHT and RF AFC CHK mode 1) If select any of THEATER / LOW LIGHT / HIGH LIGHT / RF AFC CHK items, and the LEFT / RIGHT( SERVICE MENU ( MAIN MENU ), the screens will be displayed as shown in figure page later. 2) Then the settings or verifications can be performed.

) key is pressed from

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No. 51803

AV-27230

SERVICE
SERVICE MENU PICTURE THEATER LOW LIGHT RF AFC CHK SELECT BY OPERATE BY

MENU (MAIN MENU)

SCREEN

PICTURE MODE

SOUND HIGH LIGHT 1. BRIGHT STATUS SELECT BY EXIT BY
EXITIT EXITIT

*** ***** **** **** EXIT BY
EXITIT

EXIT BY

SELECT BY OPERATE BY



SOUND MODE

1. IN LEVEL STATUS SELECT BY OPERATE BY

*** ***** **** **** EXIT BY
EXITIT

THEATER MODE(1/2)

THEATER MODE(2/2)

TINT COLOR PICTURE BRIGHT DETAIL R CUT G CUT SELECT BY OPERATE BY

*** *** *** *** *** *** ***

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

1/2 EXIT BY
EXITIT

*** *** *** *** *** ***

CD MAT RY GAIN GY PHAS CORING

* * * *

CMP CD CMP RY CMP GY CMP COR

* * * * 2/2

SELECT BY OPERATE BY

EXIT BY
EXITIT

LOW LIGHT MODE

BRIGHT *** BRIGHT

*** *** *** EXIT BY
EXITIT

RF AFC CHK MODE [DO NOT ADJUST]

HIGH LIGHT MODE

TOO HIGH RF AFC FINE STATUS SELECT BY OPERATE BY

GOOD

TOO LOW ON *** ***** **** **** EXIT BY
EXITIT

HIGH LIGHT *** *** EXIT BY
EXITIT

No. 51803

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AV-27230

(4) Setting method 1) UP / DOWN (/)key. Select the SETTING ITEM. 2) LEFT / RIGHT( ) key. Setting (adjust) the SETTING VALUE of the SETTING ITEM. When the key is released the SETTING VALUE will be stored (memorized). 3) EXIT key Return to the previous screen.
SETTING ITEM

1. BRIGHT STATUS SELECT BY OPERATE BY

*** ******** EXIT BY
IT EXIT

PICTURE MODE
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.

1. IN LEVEL STATUS SELECT BY OPERATE BY

*** ******** EXIT BY
IT EXIT

SOUND MODE

The letter of the selected Items are displayed in yellow.

TINT COLOR PICTURE BRIGHT DETAIL R CUT G CUT SELECT BY OPERATE BY

*** ** * *** ** * *** ** * *** ** * *** ** * *** ** * *** ** *

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

*** ** * *** ** * *** ** * *** ** * *** ** * *** ** *

CD MAT RY GAIN GY PHAS CORING 1/2 SELECT BY OPERATE BY

* * * *

CMP CD CMP RY CMP GY CMP COR

* * * * 2/2 EXIT BY
EXITIT

EXIT BY
EXITIT

THEATER MODE(1/2)

THEATER MODE(2/2)

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No. 51803

AV-27230

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 5 setting items in the video mode No.6 EXT BRI, No.7 EXT PICT, No.8 EXT CLR, No.9 EXT TINT and No.10 EXT DTL are linked to the
items in the TV MODE No.1 BRIGHT, No.2 PICTURE, No.3 COLOR, No.4 TINT and No.5 TV DTL 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 parenthesis are offset values.)

" When the 5 items (No.6, 7, 8, 9 and 10) are adjusted in the video mode, the setting values in each item are changed independently.
Initial setting value No. Setting (Adjustment) items Variable range AV-27230/S 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. BRIGHT PICTURE COLOR TINT TV DTL EXT BRI. EXT PICT. EXT CLR EXT TINT EXT DTL CMP BRI CMP PICT CMP CLR CMP TINT CMP DTL CMP R CT CMP G CT CMP B CT CMP R DR CMP B DR WPL C TRAP CORING CMP CORI TV SHAP EXT SHAP CMP SHAP RGB CONT TV ID S EXT ID S 000127 000127 000127 000127 00063 ±025 ±025 ±025 ±025 000063 ±025 ±025 000127 000127 000063 ±025 ±025 ±025 ±025 ±025 000 / 001 000 / 001 000 / 001 000 / 001 000 / 001 000 / 001 000 / 001 000063 000 / 001 000 / 001 064 100 055 087 050 ±000 +002 ±000 -005 050 -001 ±000 072 037 050 +008 ±000 +008 ±000 -002 001 000 001 001 001 001 001 016 000 000 AV-27230/R 064 100 055 087 050 ±000 +002 ±000 -005 050 -001 ±000 072 037 050 +008 ±000 +008 ±000 -002 001 000 001 001 001 001 001 016 000 000

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AV-27230

Initial setting value No. Setting (Adjustment) items Variable range AV-27230/S 31. 32. 33. 34. 35. 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. F ID Y MUTE SUB CONT R Y GAIN CMP R Y G Y PHAS CMP G Y CD MATRI CMP CD M BLK ST DC REST CLR GMM UV / CBCR AT FLESH ABL GAIN ABL ST P RGB ABCL TV B/T EXT B/T GMM PNT BUZZ RF AGC AFT SENS R/G DRV BLK SW V S COR V LIN V SIZE V AGC TV AFC EXT AFC V POSI H POSI TV V FR EXT V FR STND BY V RMP RE V 48HZ V EHT H EHT 000 / 001 000 / 001 000015 000 / 001 000 / 001 000 / 001 000 / 001 000003 000003 000003 000003 000 / 001 000 / 001 000 / 001 000003 000003 000 / 001 000 / 001 000 / 001 000003 000 / 001 000063 000 / 001 000 / 001 000 / 001 000015 000015 000127 000 / 001 000003 000003 000007 000031 000003 000003 000 / 001 000 / 001 000 / 001 000007 000007 000 000 008 001 001 001 001 003 001 001 001 000 000 000 000 003 001 001 000 003 000 045 001 001 000 011 012 037 000 001 002 000 015 000 003 000 001 000 000 000 AV-27230/R 000 000 008 001 001 001 001 003 001 001 001 000 000 000 000 003 001 001 000 003 000 045 001 001 000 011 012 037 000 001 002 000 015 000 003 000 001 000 000 000

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No. 51803

AV-27230

Initial setting value No. Setting (Adjustment) items Variable range AV-27D230/S 71. 72. 73. 74. 75. 76. 77. 78. 79. 80. 81. 82. 83. 84. 85. 86. 87. 88. 89. 90. 91. 92. 93. 94. 95. 96. 97. 98. 99. V BLK L V BLK U CCD IN H BLK OVER MD APACON L RF S/N T EX S/N T R S/N V1 R S/N V2 R S/N V3 R S/N V4 E S/N V1 E S/N V2 E S/N V3 E S/N V4 COR LEV VNR CHK VC SN TM VC SN SP CH MUTE OSD HP OSD VP FM TRAP OSC SEL SD SEL VF LK EX F LOCK AFC HIGH 000003 000003 000 / 001 000 / 001 000 / 001 000 / 001 000 / 001 000 / 001 000063 000063 000063 000063 000063 000063 000063 000063 000003 000255 000255 000255 000 / 001 000031 000031 000 / 001 000 / 001 000 / 001 000 / 001 000002 000064 000 001 000 000 001 001 000 000 000 000 000 000 000 000 000 000 000 000 000 000 000 018 008 000 001 001 000 002 031 AV-27230/R 000 001 000 000 001 001 000 000 000 000 000 000 000 000 000 000 000 000 000 000 000 018 008 000 001 001 000 002 031

SOUND MODE
Initial setting value No. Setting (Adjustment) item Variable range AV-27230/S 024 000 032 000 027 014 021 000 034 -001 -001 AV-27230/R 024 000 032 000 027 014 021 000 034 -001 -001

1. 2. 3. 4. 5. 6. 7. 8. 9. 10. 11.

IN LEVEL FH MON ST VCO PILOT FILTER LOW SEP HI SEP 5FH MON SAP VCO BBE BASS BBE TRE

000063 000 / 001 000063 000 / 001 000063 000063 000063 000 / 001 000063 ±010 ±010

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AV-27230

THEATER MODE
Initial setting value Setting (Adjustment) item Variable range AV-27230/S 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 PHAS CORING CMP CD CMP RY CMP GY CMP COR ±20 ±20 ±50 ±20 ±20 ±20 ±20 ±20 -99+99 -99+99 03 03 03 03 01 01 01 03 01 01 01 -06 -05 -08 ±00 +03 ±00 ±00 ±00 +06 -18 +01 ±00 +01 +01 +01 ±00 +01 +01 +01 ±00 +01 AV-27230/R -06 -05 -08 ±00 +03 ±00 ±00 ±00 +06 -18 +01 ±00 +01 +01 +01 ±00 +01 +01 +01 ±00 +01

LOW LIGHT MODE
Setting (Adjustment) item R CUTOFF G CUTOFF B CUTOFF Variable range 0255 0255 0255 Initial setting value 85 85 85

HIGH LIGHT MODE
Setting (Adjustment) item G DRIVE B DRIVE Variable range 0 255 0 255 Initial setting value 60 60

RF AFC CHECK MODE
Setting (Adjustment) item RF AFC FINE Variable range ON / OFF FIXED Initial setting value ON FIXED DO NOT ADJUST

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AV-27230

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 to TP-91 (B1) and TP-E("). " 3. Confirm that the voltage is DC134V-2.5V .
+2V

DC Voltmeter TP-91 (B1) TP-E(") "

ADJUSTMENT OF VIDEO / CHROMA, DEFLECTION CIRCUIT
Item RF. AGC adjustment Measuring instrument Test point Adjustment part No.52 RF AGC 1. 2. 3. 4. Description Receive a broadcast. Select "No.52 RF AGC" of the PICTURE MODE. Press the MUTING key and turn off the color. With the MENU LEFT key, get noise in the screen picture. (0 side of setting value) 5. Press the MENU RIGHT key and stop when noise disappears from the screen. 6. Change to other channels and make sure that there is no irregularity. 7. Press the MUTING key and get color out.

FOCUS adjustment

Signal generator

FOCUS VR [In HVT]

1. Receive a crosshatch signal. 2. While looking at the screen, adjust FOCUS VR so that the vertical and horizontal lines will be clear and in fine detail. 3. Make sure that the picture is in focus even when the screen gets darkened.

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AV-27230

Item V.SIZE Adjustment

Measuring instruments Signal generator

Test point

Adjustment part No.58 V.SIZE

Description 1. Receive a crosshatch signal. 2. Select No.58 V.SIZE in the PICTURE MODE. 3. Set the initial setting value of No.58 V.SIZE with the LEFT / RIGHT key of the MENU. 4. Adjust No.58 V.SIZE until the vertical screen size becomes the value as shown table below.

Application model
Screen size

Vertical screen size

AV-27230/S

89.0%

Screen size

Picture size 100%

AV-27230/R

92.0%

Picture size

H.POSITION Adjustment

Signal generator

No.63 H.POSI

1. Receive a crosshatch signal. 2. Select the No.63 H.POSI of the PICTURE MODE. 3. Set the initial setting value of the No.63 H.POSI with the LEFT / RIGHT key of the MENU. 4. Adjust the No.63 H.POSI until the screen will be horizontally centered.

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AV-27230

Item WHITE BALANCE (Low Light) Adjustment

Measuring instruments Signal generator

Test point

Adjustment part BRIGHT R. CUTOFF G. CUTOFF B. CUTOFF SCREEN VR [In HVT]

Description 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 with the LEFT / RIGHT key of the remote control unit. 4. Set the initial setting value of R CUTOFF, G CUTOFF and B CUTOFF with the orkey(R), orkey(G), orkey(B) of the remote control unit. 5. Display a single horizontal line by pressing the 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 to keys of the remote control unit. 9. Turn the screen VR to where the single horizontal line glows faintly. 10. Press the key to return to the regular screen. The

[LOW LIGHT] MODE

G CUTOFF BRIGHT B CUTOFF R CUTOFF BRIGHT *** *** *** *** EXIT BY BRIGHT
IT EXIT

EXIT key is the cancel key for the WHITE

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

BALANCE.

1
R CUTOFF

2
G CUTOFF

3
B CUTOFF

4
R CUTOFF

5
G CUTOFF

6
B CUTOFF

7

8

9

WHITE BALANCE (High Light) Adjustment

Signal generator

G. DRIVE B. DRIVE

1. Receive a monoscope pattern signal. 2. Select theHIGH LIGHTMODE in the SERVICE MENU. 3. Set the initial setting value of G DRIVE and B DRIVE with the , and , keys of the remote control unit. 4. Adjust the screen until it becomes white using the , , and keys of the remote control unit. The EXIT key is the cancel key for the WHITE BALANCE mode.

[HIGH LIGHT] MODE

Remote Control Unit Key Operation
G DRIVE B DRIVE

key : H.LINE ON key : H.LINE OFF key : EXIT

HIGH LIGHT ** * ** * EXIT BY
EXITIT

key : G DRIVE key : G DRIVE key : B DRIVE key : B DRIVE

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AV-27230

Item SUB BRIGHT Adjustment

Measuring instruments

Test point

Adjustment part No.1 BRIGHT

Description 1. Receive a broadcast. 2. Select 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 MENU. 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.

SUB CONTRAST Adjustment

No.2 PICTURE

1. Receive a broadcast. 2. Select 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 MENU. 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.

SUB COLOR Signal adjustment generator Oscilloscope Remote control unit

TP-R TP-E(#) # [CRT SOCKET PWB]

No.3 COLOR

[ Method of adjustment without measuring instrument ]

1. Receive a broadcast. 2. Select "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 MENU. 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.

[ Method of adjustment using measuring instrument ]

Cy G B

1. Input the full field color bar signal (75% white). 2. Select "No.3 COLOR" to the PICTURE MODE. 3. Set the initial setting value of the "No.3. COLOR" with the LEFT/RIGHT key of the MENU. 4. Connect the oscilloscope between TP-R and TP-E. 5. Adjust COLOR and bring the value of (A) in the illustration to the voltage +20V (VW-R).

W
Y Mg

(A)

(-) 0V (+)

Application Model AV-27230/S AV-27230/R

COLOUR adjustment voltage +20V +20V

R

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AV-27230

Item SUB TINT adjustment

Measuring instruments Signal generator Oscilloscope Remote control unit

Test point TP-R TP-E(#) # [CRT SOCKET PWB]

Adjustment part No.4 TINT

Description [ Method of adjustment without measuring instrument ]

1. Receive a broadcast. 2. Select "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 MENU. 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.

[ Method of adjustment using measuring instrument ]

1. Input the full field color bar signal (75% white). 2. Select "No.4 TINT" to the PICTURE MODE. 3. Set the initial setting value of the "No.4 TINT" with the LEFT/RIGHT key to the MENU. 4. Connect the oscilloscope between TP-R and TP-E. 5. Adjust TINT and bring the value of (B) in the illustration to the voltage +17V (VW-Y).

Cy G B

(-) W 0V (+) Y (B)

Mg R
Application Model AV-27230/S AV-27230/R COLOUR adjustment voltage +17V +17V

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AV-27230

ADJUSTMENT OF MTS CIRCUIT
Item MTS INPUT LEVEL check Measuring instrument Test point Adjustment part No.1 IN LEVEL Description 1. Select the "No.1 IN LEVEL" of the SOUND MODE. 2. Verify that the "No.1 IN LEVEL" is set at its initial setting value.

MTS STEREO Signal VCO generator adjustment Frequency counter

R OUT [AUDIO OUT]

No.2 FH MON. No.3 ST VCO

1. Receive a RF signal (nonmodulated sound signal) from the antenna terminal. 2. Select the "No.2 FH MON." of SOUND MODE, and change the setting value from 0 to 1. 3. Connect the Frequency Counter to R OUT RCA pin of the AUDIO OUT. 4. Select the "No.3 ST VCO". 5. Set the initial setting value of the "No.3 ST VCO" with the LEFT/RIGHT key of the menu. 6. Adjust the "No.3 ST VCO" so that the Frequency Counter will display 15.73kHz±0.1kHz. 7. Select the "No.2 FH MON." of the SOUND MODE, and reset the setting value from 1 to 0.

MTS SAP VCO adjustment

Signal generator Frequency counter

MPX Connector 4pin SDA 3pin GND R OUT [AUDIO OUT]

No.8 5FH MON. No.9 SAP VCO

1. Receive a RF signal (non modulated sound signal) from the antenna terminal. 2. Connect between pin4ofMPXconnector and GND (Pin 3ofMPXconnector) through 1M Resistor. 3. Select the "No.8 5FH MON." of the SOUND MODE, and reset the setting value from 0 to 1. 4. Connect the Frequency Counter to R OUT RCA pin of the AUDIO OUT. 5. Select the "No.9 SAP VCO". 6. Set the initial setting value of "No.9 SAP VCO" with the LEFT/RIGHT key of the menu. 7. Adjust the "No.9 SAP VCO" so that the Frequency Counter will display 78.67kHz±0.5kHz. 8. Select the "No.8 5FH MON." of the SOUND MODE, and reset the setting value from 1 to 0.

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No. 51803

AV-27230

Item MTS FILTER check

Measuring instrument

Test point

Adjustment part No.5 FILTER

Description 1. Select the "No.5 FILTER" of the SOUND MODE. 2. Verify that the "No.5 FILTER" is set at its initial setting value.

MTS SEPARATION adjustment

TV audio multiplex signal generator Oscilloscope

No.6 LOW SEP. L OUT R OUT [AUDIO OUT] No.7 HI SEP.

L-Channel signal waveform

R-Channel crosstalk portion Minimum

1. Input a stereo L signal (300Hz) from the TV audio multiplex signal generator to the antenna terminal. 2. Connect an oscilloscope to L OUT RCA pin of the AUDIO OUT, and display one cycle portion of the 300Hz signal. 3. Change the connection of the oscilloscope to R OUT RCA pin of the AUDIO OUT, and enlarge the voltage axis. 4. Select the "No.6 LOW SEP." of the SOUND MODE. 5. Set the initial setting value of the "No.6 LOW SEP." with the LEFT/RIGHT key of the menu. 6. Adjust the "No.6 LOW SEP." so that the stroke element of the 300Hz signal will become minimum. 7. Change the signal to 3kHz, and similarly adjust the "No.7 HI SEP.".

1 cycle

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AV-27230

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 switch to on. (2) As shown in Fig. 1, set the resistor between (3) Make sure that the screen picture disappears. (4) Temporarily unplug the power plug. (5) Remove the resistor replaced X connector 1 and 3 . X connector 1 and 3 .

(6) Again plug the power plug, make sure that the normal picture is displayed on the screen.

T921 RESISTOR 18.84k±1%1/4W

Q953 D957 R957 POWER ON OFF Q562 T522 Q561 D563 R564 D562 C562 R563 R562 C561 D561 R561 D565 BW 4 3 2 1 X CONNECTOR HEATER

Fig. 1

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No. 51803

AV-27230

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 CRT NECK protector Also detected if the power supply line output from the HVT (High voltage Transformer) has shorted with the ground. Details of detection When the vertical circuit Scorrection capacitor C427 is shorted, detect the potential drop of the C427, and prevent the burn damage to the CRT NECK. (Grounding of shorting of the power supply output from the HVT to the vertical circuit, and the small signal power supply is also detected.) Method of detection The microcomputer detects at 1 second intervals. If NG is detected for more than 1 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.

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AV-27230

REPLACEMENT OF CHIP COMPONENT
! 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.

! 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.

! 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) Shift with tweezers and remove the chip part.

(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 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

(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.

A B

C

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

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

C

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No. 51803

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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)315-5000 (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

&

4

AV27230S-UCM #4 AV27230R-UCM #4

Printed in Japan VP 0104 DP3051