JVC AV-28R4SK Service Manual Download Page 6

1-6 (No.YA060)

SECTION 2

SPECIFIC SERVICE INSTRUCTIONS

2.1

FEATURES

• New chassis design enable use of an interactive on screen

control.

• The TELETEXT SYSTEM has a built-in FASTEXT (UK

system), TOP (German system) and WST (world standard
system) system.

• Because this TV unit corresponds to multiplex broadcast,

users can enjoy music programs and sporting events with live
realism. In addition, BILINGUAL programs can be heard in
their original language.

• Users can make VCR dubbing of picture and sound by

controlling the AV selector to select an optional source at the
EXT-2 output.

2.2

21-pin Euro connector (SCART) : EXT-1/EXT-2/EXT-3

(P-P= Peak to Peak, B-W= Blanking to white peak)

Pin No. Signal designation

Matching value

EXT-1

EXT-2

EXT-3

1

AUDIO R output

500mV(rms) (Nominal), Low impedance

Used (TV OUT) Used (LINE OUT)

Not used

2

AUDIO R input

500mV(rms) (Nominal), High impedance

Used (R1)

Used (R2)

Used (R3)

3

AUDIO L output

500mV(rms) (Nominal), Low impedance

Used (TV OUT) Used (LINE OUT)

Not used

4

AUDIO GND

Used

Used

Used

5

GND (B)

Used

Used

Used

6

AUDIO L input

500mV(rms) (Nominal), High impedance

Used (L1)

Used (L2)

Used (L3)

7

B input

700mV

(B-W)

, 75

Used

Used

Not used

8

FUNCTION SW

(SLOW SW)

Low : 0V-3V

High : 8V-12V, High impedance

Used

Used

Used

9

GND (G)

Used

Used

Used

10

SCL / T-V LINK

Not used 

Used

(SCL2 / TV-LINK)

Not used

11

G input

700mV

(B-W)

, 75

Used

Used

Not used

12

SDA

Not used 

Used (SDA2)

Not used

13

GND (R)

Used

Used

Used

14

GND (YS)

Used

Not used

Not used

15

R / C input

R : 700mV

(B-W)

, 75

 

C : 300mV

(P-P)

, 75

Used (R)

Used (C2/R)

Used (C3)

16

Ys input (FAST SW) Low : 0V-0.4V, High : 1V-3V, 75

Used

Used

Not used

17

GND (VIDEO output)

Used

Used

Used

18

GND (VIDEO input)

Used

Used

Used

19

VIDEO output

1V

(P-P)

 (Negative sync), 75

Used (TV OUT) Used (LINE OUT)

Not used

20

VIDEO / Y input

1V

(P-P)

 (Negative sync), 75

Used

Used

Used

21

COMMON GND

Used

Used

Used

20

18

16

14

12

10

8

6

4

2

21

19

17

15

13

11

9

7

5

3

1

[Pin assignment]

Summary of Contents for AV-28R4SK

Page 1: ...8T77SK AV 32R4SK AV 32T4SK AV 32T4SP AV 32T4SR AV 32T77SK TABLE OF CONTENTS 1 PRECAUTION 1 4 2 SPECIFIC SERVICE INSTRUCTIONS 1 6 3 DISASSEMBLY 1 9 4 ADJUSTMENT 1 18 5 TROUBLE SHOOTING 1 34 BASIC CHASSIS JW AV 28T77SK AV 32T77SK 1 4 7 2 5 8 0 3 6 9 P AV TV OK MENU P TV F T L AV 28R4SK AV 28T4BK AV 28T4SK AV 28T4SP AV 28T4BR AV 28T4SR AV 32R4SK AV 32T4SK AV 32T4SP AV 32T4SR ...

Page 2: ...sumption 125W Max 115W Avg Standby 2 7W 120W Max 110W Avg Standby 2 7W Picture Tube Visible size 66cm measured diagonally H 58 3cm V 33 0cm High Voltage 31 0kV 1kV 1 5kV at zero beam current Speaker MAIN 6 5cm 13cm oval type 2 CENTER 4cm 16cm oval type 2 SUB WOOFER 13cm round type 1 6 5cm 13cm oval type 2 Audio Power Output MAIN 10W 10W CENTER 10W SUB WOOFER 18W 10W 10W Aerial Input Terminal 75 Ω ...

Page 3: ...put AC 220V AC240V 50Hz Power Consumption 125W Max 115W Avg Standby 2 7W 120W Max 110W Avg Standby 2 7W Picture Tube Visible size 76cm measured diagonally H 67 4cm V 38 4cm High Voltage 31 0kV 1kV 1 5kV at zero beam current Speaker MAIN 6 5cm 13cm oval type 2 CENTER 4cm 16cm oval type 2 SUB WOOFER 13cm round type 1 6 5cm 13cm oval type 2 Audio Power Output MAIN 10W 10W CENTER 10W SUB WOOFER 18W 10...

Page 4: ...eplacements or alternatives approved by the manufacturer of the complete product 7 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 10kΩ 2W resistor to the anode button 8 When service i...

Page 5: ...haracteristics 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 the 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 haza...

Page 6: ...V rms Nominal High impedance Used R1 Used R2 Used R3 3 AUDIO L output 500mV rms Nominal Low impedance Used TV OUT Used LINE OUT Not used 4 AUDIO GND Used Used Used 5 GND B Used Used Used 6 AUDIO L input 500mV rms Nominal High impedance Used L1 Used L2 Used L3 7 B input 700mV B W 75Ω Used Used Not used 8 FUNCTION SW SLOW SW Low 0V 3V High 8V 12V High impedance Used Used Used 9 GND G Used Used Used ...

Page 7: ...d Austria Italy Spain Portugal Sweden Denmark Finland Norway Greece DOLBY SORROUND YES NO SUB WOOFER YES NO POWER PLUG UK type 3pin EU type 2pin S VIDEO INPUT YES NO Item AV 32R4SK AV 32T4SK AV 32T4SR AV 32T77SK AV 32T4SP CABINET TYPE A B A DESTINATION England England Ireland England Germany Belgium France Switzerand Austria Italy Spain Portugal Sweden Denmark Finland Norway Greece DOLBY SORROUND ...

Page 8: ...2 EHT I EHT overvoltage protect 96 V1 8ADC Supply video ADC 33 Ssif RefIn Avl RefOut O L OTHER 97 IntO I REMOCON 34 AudioIn5L I Audio 5 input Left 98 P10 Int1 I AV_LINK IN 35 AudioIn5R I Audio 5 input Right 99 P11 TO O AV_LINK OUT 36 AudOutSL O Audio output Left 100 V1 8C2 digital 1 8V 37 AudOutSR O Audio output Right 101 VssC2 GND 38 DecsDem decoupling sound demod 102 P04 I2SWs I O I2S_WS 39 QssO...

Page 9: ... CHASSIS and release the two claws at the bottom of and both sides of the MAIN CHASSIS 2 Then withdraw the MAIN CHASSIS backward from the front cabinet If necessary detach the wire clamp connectors etc 3 1 6 REMOVING THE MAIN SPEAKER Remove the REAR COVER 1 Remove the 2 screws E and detach the MAIN SPEAKER HOLDER as shown in Fig 5 When removing the screws E of the MAIN SPEAKER HOLDER the lower sid...

Page 10: ...woofer unit is mounted on the TV Always move the TV and woofer unit together when removing the TV from the box or when moving the woofer unit If the TV is tilted during movement the woofer unit may fall Be careful to keep the TV level when moving it Do not grip the woofer unit when moving the TV Do not place objects on the woofer unit duct Fig 4 L M N N L L SP BOX B SP BOX T SPEAKER BASS INT DUCT ...

Page 11: ...T CABINET MAIN SPEAKER SPEAKER CRT SOCKET PWB CENTER SIDE CONTROL PWB POWER DEF PWB AV JACK PWB MAIN PWB DOLBY PWB CLAW CLAW MAIN CHASSIS FRONT CONTOL PWB CONTROL BASE AV TERMINAL BOARD A F SIDE CONTROL JACK ASSY B POWER CORD E G D MAIN SPEAKER HOLDER SUB WOOFER UNIT SUB WOOFER CORD ...

Page 12: ... AV 28T series AV 32T series are slightly different from this figure you can use the exploded view for disassembling other models in same step as AV 32T4SP FRONT CABINET CRT SOCKET PWB AV JACK PWB SIDE CONTROL PWB MAIN PWB B A G E F MAIN SPEAKER MAIN SPEAKER HOLDER SIDE CONTROL JACK ASSEMBLY CLAW CLAW POWER DEF PWB AV TERMINAL BOAD FRONT CONTOL PWB CONTROL BASE ...

Page 13: ...ing steps The CRT change table should preferably be smaller that the CRT surface and its height be about 35cm Fig 7 Fig 8 Fig 9 COATING OF SILICON GREASE FOR ELECTRICAL INSULATION ON THE CRT ANODE CAP SECTION Subsequent to replacement of the CRT and HV transformer or repair of the anode cap etc by dismounting them be sure to coat silicon grease for electrical insulation as shown in Fig 9 Wipe arou...

Page 14: ...OWN key and adjust it with the FUNCTION RIGHT LEFT keys The letter of the selected item is displayed in yellow 5 A setup will become effective if the main power is shut off 5 Receiving channel setting Refer to the OPERATING INSTRUCTIONS and set the receive channels Channels Preset as described 6 User settings Check the user setting items according to the given in page later Where these do not agre...

Page 15: ...ccording to preset CH EXT AUTO 4 3 AUTO ASPECT PANORAMIC Setting item Setting position STEREO I II Stereo sound BASS Centre TREBLE Centre BALANCE Centre HYPER SOUND OFF DOLBY VIRTUAL AV 28T77SK AV 32T77SK OFF TV SPEAKER AV 28R4SK AV 32R4SK ON SUROUND MODE AV 28R4SK AV 32R4SK DOLBY PRO LOGIC II TV SPEAKER L C R LEFT MAX CENTRE MAX RIGHT MAX LS MAX RS MAX WOOFER MAX DISTANCE 0 Setting item Setting p...

Page 16: ...E 1 WDR R 2 WDR G 3 WDR B 2 V C 1 SCREEN 2 CUTOFF R G 3 WDR R G B 4 BRIGHT 5 CONT 6 COLOUR 7 HUE 8 BLACK OFFSET B Y 9 SHARP 10 Y DELAY 11 TINT DVD 12 RGB BLK 6 VPS Do not adjust VPS PDC WSS SN 3 AUDIO Do not adjust 1 DCX0 ADJ 2 ERROR LIMIT 3 A2 ID THR 7 SHIPPING Do not adjust ON OFF 4 DEF 1 V SHIFT 2 V SLOPE 3 V SIZE 4 H CENT 5 H SIZE 6 TRAPEZ 7 EW PIN 8 COR UP 9 COR LOW 10 ANGLE 11 BOW 12 V S CR ...

Page 17: ...the tweezers and remove the chip part Transistors diodes variable resistors etc 1 Apply extra solder to each lead 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 NOTE After removing the part remove remaining solder from the pattern 2 How to install Chip parts Resistors capacitors etc 1 Apply solder to the pattern as i...

Page 18: ...ms of this service adjustment 4 2 PRESET SETTING BEFORE ADJUSTMENT Unless otherwise specified in the adjustment items preset the following functions with the REMOTE CONTROL UNIT 4 3 MEASURING INSTRUMENT AND FIXTURES 1 DC voltmeter or digital voltmeter 2 Oscilloscope 3 Signal generator Pattern generator PAL SECAM NTSC 4 Remote control unit 4 4 ADJUSTMENT ITEMS CHECK ITEM B1 POWERSUPPLY check HIGH V...

Page 19: ...POWER DEF PWB FRONT CONTROL PWB R L HV K B B PW F X W IC941 CN004 CN003 TOP CRT SOCKET PWB TP 47B E1 SOLDER SIDE HVT 1 5 1 B1 2 N C 3 X ray 4 X ray 5 GND AV JACK PWB CN001 TUNER DOLBY PWB AV 28R4SK AV 32R4SK 28 MODEL 32 MODEL CN009 S SW SC IC702 TP 47G TP 47R TP E CN008 MEMORY IC Only AV 28R4SK AV 32R4SK AV 28R4SK AV 32R4SK CN3008 CN3009 SC VM2 FOCUS1 FOCUS2 SCREEN FOCUS1 SCREEN ...

Page 20: ... adjusts the setting values of the VIDEO CHROMA circuit 3 AUDIO This mode adjusts the setting values of the multiplicity SOUND circuit Do not adjust 4 DEF This mode adjusts the setting values of the DEFLECTION circuit for each aspect mode given below 5 VSM PRESET This mode adjusts the initial setting values of COOL NORMAL and WARM VSM Video Status Memory 6 VPS This mode shows the monitor of the VP...

Page 21: ... 1 DCX0 ADJ 2 ERROR LIMIT 3 A2 ID THR AUDIO 3 AUDIO 1 DCX0 ADJ NOT NICAM 1 VCO 1 IF 2 DELAY POINT BRIGHT STD SOFT 5 VSM PRESET VSM PRESET BRIGHT 1 BRIGHT 1 BRIGHT 2 CONT 3 COLOUR 4 SHARP 5 HUE 1 WDR R 2 WDR G 3 WDR B Do not adjust Do not adjust PICTURE MODE COOL NORM WARM COLOR TEMP 1 SCREEN 2 CUTOFF R G 3 WDR R G B 4 BRIGHT 5 CONTRAST 6 COLOUR 7 HUE 12 RGB BLK 8 BLACK OFFSET 9 SHARP 10 Y DELAY 11...

Page 22: ...ED 63 63 0 0 0 0 0 GREEN 63 63 0 0 0 0 0 3 WDR RED 63 63 0 0 0 0 0 GREEN 63 63 0 0 0 0 0 BLUE 63 63 0 0 0 0 0 4 BRIGHT 63 63 0 0 0 0 0 5 CONTRAST 63 63 10 10 10 10 0 6 COLOUR 63 63 0 0 0 0 0 7 HUE 63 63 0 0 8 BLACK OFFSET B Y 0 3 3 Setting item Variable range Setting value PAL SECAM NTSC NTSC4 43 RGB RF VIDEO RF VIDEO RF VIDEO RF VIDEO 9 SHARP 63 63 5 5 5 5 5 5 5 5 5 Setting item Variable range Se...

Page 23: ...9 0 0 0 0 0 0 0 0 0 6 TRAPEZ 32 31 4 0 0 0 2 0 0 0 0 0 0 0 7 EW PIN 32 31 15 0 0 0 0 0 0 0 0 0 0 0 8 COR UP 32 31 0 0 0 0 0 0 0 0 0 0 0 0 9 COR LO 32 31 0 0 0 0 7 0 0 0 0 0 0 0 10 ANGLE 32 31 0 0 0 0 0 0 0 0 0 0 0 0 11 BOW 32 31 0 0 0 0 0 0 0 0 0 0 0 0 12 V S COR 32 31 14 0 10 0 4 0 0 0 0 0 0 0 13 V LIN 32 31 3 0 6 0 8 0 0 0 0 0 0 0 Item Variable range Setting value PICTURE MODE COLOUR TEMP BRIGHT...

Page 24: ...Chassis GND 2 V C 12 RGB BLK 1 Receive the any broadcast 2 Select 2 V C from the SERVICE MENU 3 Select 12 RGB BLK 4 Press the FUNCTION key to find the cut off screen Black screen 5 Connect a HV voltmeter to CRT ANODE and chassis GND A ground side is connected previously 6 Make sure that the voltage is DC 31 0kV 1kV 1 5kV 7 Press the FUNCTION key to return to service menu NOTE When removing a prove...

Page 25: ... A part horizontal line may become uniform at the line centre and its periphery Fig 1 5 Make sure that when the screen is darkened the lines remain in good focus Fig 1 FOCUS 28 MODELS Signal generator FOCUS VR In HVT 1 Receive the cross hatch signal 2 Set the ZOOM mode to FULL 3 While looking at the screen adjust the FOCUS VR to the vertical and horizontal lines will be clear and infine detail 4 M...

Page 26: ...ect 4 DEF from the SERVICE MENU 4 Select 1 V SHIFT 5 Set the initial setting value of 1 V SHIFT 6 Adjust vertical position to make A B 7 Check the adjustment value above in other zoom mode If it is a wrong adjustment re adjust in FULL mode and adjust by 1 V SHIFT 8 Press the MENU key and memorize the set value V SIZE Signal generator Remote control unit 4 DEF 3 V SIZE 1 Receive the cross hatch sig...

Page 27: ... table 7 Make sure that the horizontal screen size of the each ASPECT mode is in the below table 8 Press the MENU key and memorize the set value NOTE 14 9 ZOOM and REGULAR are length of 90 The value in shows NTSC adjustment value SIDE PIN Signal generator Remote control unit 4 DEF 7 EW PIN 1 Receive the cross hatch signal 2 Set the ZOOM mode to FULL 3 Select 4 DEF from the SERVICE MENU 4 Select 7 ...

Page 28: ...itial setting value of 8 COR UP 6 Adjust to bring the straight line at the upper corner 7 Select 9 COR LO 8 Set the initial setting value of 9 COR LO 9 Adjust to bring the straight line at the low corner 10 Press the MENU key and memorize the set value ANGLE Signal generator Remote control unit 4 DEF 10 ANGLE In case where there is a parallelogrammical distortion of images on the screen 1 Receive ...

Page 29: ...rator Remote control unit 4 DEF 12 V S CR 13 V LIN When the vertical linearity has been deteriorated remarkably perform the following steps 1 Receive the cross hatch signal 2 Set the ZOOM mode to FULL 3 Select 4 DEF from the SERVICE MENU 4 Select 13 V LIN 5 Set the initial setting value of 13 V LIN 6 Select 12 V S COR 7 Set the initial setting value of 12 V S COR 8 Adjust 13 V LIN and 12 V S COR s...

Page 30: ... value SUB CONTRAST Remote control unit 2 V C 5 CONT 1 Receive the any broadcast 2 Set the ZOOM mode to FULL 3 Set the PICTURE mode to STD 4 Select 2 V C from the SERVICE MENU 5 Select 5 CONT 6 Set the initial setting value of 5 CONT 7 If the contrast is not the best with the initial setting value make fine adjustment until you get the best contrast 8 Press the MENU key and memorize the set value ...

Page 31: ...ar with 75 white from the EXT terminal 2 Set the initial setting value of NTSC 3 58 COLOUR 3 Adjust NTSC 3 58 COLOUR and bring the value of A in the illustration to the values as shown given billow Voltage difference between white W and blue B 4 Press the MENU key and memorize the setting value NTSC 4 43 COLOUR 1 When NTSC 3 58 COLOUR set NTSC 4 43 COLOUR will automatically set SUB HUE 1 Remote co...

Page 32: ...it TP 47B TP E CRT SOCKET PWB 2 V C 8 BLACK OFFSET 1 Receive the SECAM full field colour bar signal 2 Set the ZOOM mode to FULL 3 Set the PICTURE mode to STD 4 Select 2 V C from the SERVICE MENU 5 Select 8 BLACK OFFSET 6 Set the initial setting value of 8 BLACK OFFSET 7 Connect the oscilloscope between TP 47B and TP E at the CRT SOCKET PWB 8 Press 1 and 2 keys alternately turn the colour on and of...

Page 33: ...MODE to BRIGHT 4 Adjust the FUNCTION UP DOWN and key to bring the set values of 1 BRIGHT to 5 HUE to the values shown in the 5 VSM PRESET 5 Press the MENU key and set the PICTURE MODE to STD 6 Make similar adjustment as in 3 above 7 Press the MENU key and set the PICTURE MODE to SOFT 8 Make similar adjustment as in 3 above 9 Press the MENU key and set the COLOUR TEMP to COOL 10 Adjust the FUNCTION...

Page 34: ...1 34 No YA060 SECTION 5 TROUBLE SHOOTING This service manual does not describe TROUBLE SHOOTING ...

Page 35: ... No YA060 AV MULTIMEDIA COMPANY VIDEO DISPLAY CATEGORY 12 3 chome Moriya cho kanagawa ku Yokohama kanagawa prefecture 221 8528 Japan VICTOR COMPANY OF JAPAN LIMITED WPC Printed in Japan ...

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