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Service Support

Service and repair of

this product is

supported by

Panasonic's LUCI

interface.

This interface provides a

link between the TV and

a standard PC to allow a

number of diagnostic

and control functions to

be performed.

For more details contact

your local Panasonic

company.

BACK

EXIT

TX-28/25/21MD4 Service Manual

Safety

Specifications

Block Diagrams

Schematic Diagrams

PCB Views

Self Check

Service

Information

Parts List

Service Hints

Disassembly

Location of

Controls

Waveforms

Supplementary Information

Mechanical

View

Adjustments

Summary of Contents for TX-28MD4

Page 1: ...number of diagnostic and control functions to be performed For more details contact your local Panasonic company BACK EXIT TX 28 25 21MD4 Service Manual Safety Specifications Block Diagrams Schematic Diagrams PCB Views Self Check Service Information Parts List Service Hints Disassembly Location of Controls Waveforms Supplementary Information Mechanical View Adjustments ...

Page 2: ...BACK BACK BACK E Schematics H Schematic Y Schematics E PCB Y PCBs Audio Power supply Control Video ...

Page 3: ...eo 21 pin 1V p p 75Ω Audio 21 pin 500mV rms 10kΩ S Video IN Y 1V p p 75Ω 21 pin C 0 3V p p 75Ω AV2 OUT Video 21 pin 1Vp p 75Ω Audio 21 pin 500mV rms 1kΩ Selectable output 21 pin AV3 IN Audio RCAx2 500mV rms 10kΩ Video RCAx1 1V p p 75Ω High Voltage 28 5kV 1kV 28 2kV 1kV 28kV 1kV Picture Tube A66ECF50X41 66cm A59ECF50X41 59cm A51ECQ51X01 51cm Audio Output 2 x 15W Music Power 8Ω Impedance Headphones ...

Page 4: ... part on the receiver such as screw heads aerials connectors control shafts etc When the exposed metallic part has a return path to the chassis the reading should be between 4M ohm and 20M ohm When the exposed metal does not have a return path to the chassis the reading must be infinite LEAKAGE CURRENT HOT CHECK 1 Plug the AC cord directly into the AC outlet Do not use an isolation transformer for...

Page 5: ...SERVICE HINTS How to remove the rear cover 1 Remove the 9 screws as shown in Fig 2 LOCATION OF CONTROLS 3 SCREWS Fig 2 E BOARD Y BOARD FOCUS SCREEN H BOARD Fig 3 ...

Page 6: ...rotate the chassis horizontally through 90 anti clockwise 4 Move the EHT lead around to the left side of the CRT neck 5 Elevate the front of the chassis 6 Clip the chassis frame onto the bead clamper on the degauss coil as shown in Fig 5 7 Locate the base of the chassis frame into the hole marked A shown in Fig 6 8 After servicing replace the bead clamper and ensure all wiring is returned to its o...

Page 7: ...ch the TV on 2 Go into Service Mode as explained above The screen will show 3 Press the BLUE button on the remote control The screen will show 4 Press the STR button on the TV The screen will show 5 All the tuning information stored inside the TV will now be transferred to the Memory Pack This process will take 2 3 minutes to complete and when finished the screen will show Memory Pack to TV proces...

Page 8: ...ls at the front of the set at the same time pressing the STATUS button on the remote control and the screen will show If the CCU ports have been checked and found to be incorrect or not located then will appear in place of O K Service Aids To aid in the service of our current chassis there are a number of Service Aids which have been made available LUCI interface kit Linked Utility Computer Interf...

Page 9: ...275mV 64µS 64µS 3V H Out IC601 Pin 50 Vert Out IC601 Pin 31 20mS 0 7V 13µS 3 7V SCL IC1201 Pin 3 R Out E8 Pin 5 64µS 4 6V HFLB IC601 Pin 13 64µS 6 2V R Out IC601 Pin 37 64µS 275mV G Out IC601 Pin 38 275mV 64µS Vert Drive IC451 Pin 2 20mS 57V HFLB IC701 Pin 8 64µS 1 5V G Out E8 Pin 3 64µS 4 4V SVM Out IC601 Pin 34 88mV 64µS H Out IC701 Pin 5 30mV 64µS ...

Page 10: ...al Linearity V Lin 006 Optimum setting Vertical Symmetry V Sym 002 Optimum setting DVCO DVCO 005 Receive a PAL Colour Bar Pattern For DVCO alignment press Blue button wait until the colours are changing slowly and press STR Cut off DC Cut off 0171 Ug2 Test Ug2 055 O K To adjust Cutoff connect an oscilloscope to the blue cathode adjust cutoff value using the Yellow and Blue buttons until the black ...

Page 11: ...E8 4 3 5 Q353 Q352 Q351 CRT 3 2 1 7 8 9 Y2 4 3 5 IC351 TUNER Q104 5HG OXH UHHQ 9LGHR Q 9 9LGHR 2XW G OUT 38 R OUT 37 G IN 46 R IN 45 Q306 Q304 Q302 Q354 7 7 VM COILS Q905 Q907 Q909 Q908 Q906 SVM OUT 34 Q950 Q951 Q3001 G 38 B 39 Y BOARD E BOARD RGB OUTPUT VIDEO PROCESSOR MICRO PROCESSOR H3 E61 E15 1 6 8 H1 1 6 8 H BOARD TX 28MD4 TX 25MD4 ONLY TX 28MD4 TX 25MD4 ONLY 9 IC3401 Q3402 8 6 3 VIDEO SWITCH...

Page 12: ...R R 7 6 R 1 R OUT 3 L OUT 1 R OUT 3 L OUT 2 R IN 6 L IN 2 R IN 6 L IN 47 ANA_IN1 DACM_L 25 SC3_IN_R 38 SC1_IN_R 42 SC1_IN_L 41 SC2_OUT_R 27 SC2_OUT_L 28 SC2_IN_R 40 SC2_IN_L 39 Q252 Q251 2 L L 11 4 L HEADPHONE 7 R 5 L E6 1 E7 3 Q2304 Q2302 21 DACA_R 22 DACA_L E BOARD AUDIO PROCESSOR AUDIO OUTPUT AUDIO MONITOR OUT Q2303 Q2301 10 ...

Page 13: ...OCAL KEYS SWITCH MATRIX 60 Q854 52 Q853 74 IC1051 Q1052 81 AV2 8 10 AV1 8 10 12 Q856 75 Q851 Q1106 Q1105 Q1107 Q1104 51 72 73 AV LINK SLOW 2 SLOW 1 SCL 1 SDA 1 59 58 Q3006 Q3007 55 VPROT KEYSCAN ON OFF R C L E D PROT 1 SLOW 2 OUT IN SLOW 1 SERVICE SCL SDA H BOARD E BOARD VIDEO SWITCHING AUDIO PROCESSOR MICRO PROCESSOR VIDEO PROCESSOR EAROM REMOTE CONTROL RECEIVER Q1051 D1051 11 Q3401 3 ...

Page 14: ... 4 2 1 3 1 S4 B1 P2 P1 S5 S2 S7 10 9 6 8 5 6 2 6 3 1 6 12V 200V 33V 14V 14V 27V 150V 29V 7V 15V 5V D867 Q852 Q854 Q855 1 D805 R805 R814 IC850 1 2 D862 R854 33V 16 REMOTE CONTROL RECEIVER RESET MICRO PROCESSOR AUDIO PROCESSOR VIDEO PROCESSOR EPROM EAROM RESET REG REG REG IC3401 7 VIDEO SWITCHING EW CORRECTION POWER SUPPLY RGB OUTPUT V OUTPUT AUDIO OUTPUT D801 E BOARD Y BOARD E3 2 Y3 2 E1 4 1 E2 2 1...

Page 15: ...PARTS LOCATION 13 7 18 13 12 10 11 17 16 4 8 3 15 9 14 5 1 6 2 NOTE The numbers on the exploded view below refer to the mechanical section of the Replacement Parts List ...

Page 16: ...V REGULATOR IC853 AN78L08TA LED RECEIVER IC1051 RPM 637CBRL MICRO PROCESSOR IC1101 SDA5450C48 EPROM IC1102 27C2001 F09 DIODE IC1104 MN1381 R TA DIODE IC1105 MN1381 T TA AUDIO PROCESSOR IC2101 MSP3410DPOB4 AV SWITCHING IC3401 TEA2114 FUSES FUSE F802 19181 3 15 FUSE HOLDER F8021 EYF52BC FUSE HOLDER F8022 EYF52BC DIODES DIODE D251 MA2180TP DIODE D253 MA700TA5 DIODE D254 MA700TA5 DIODE D354 1SR124 4AT...

Page 17: ...SISTOR Q855 BC847B TRANSISTOR Q856 BC847B TRANSISTOR Q857 2SA1018QTA TRANSISTOR Q950 BC847B TRANSISTOR Q951 FMY4T148 TRANSISTOR Q1051 BC847B TRANSISTOR Q1052 BC847B TRANSISTOR Q1101 BC847B TRANSISTOR Q1104 BC847B TRANSISTOR Q1105 BC847B TRANSISTOR Q1106 BC847B TRANSISTOR Q1107 BC847B TRANSISTOR Q1108 BC847B TRANSISTOR Q2101 BC857B TRANSISTOR Q2102 BC857B TRANSISTOR Q2103 BC857B TRANSISTOR Q2301 BC...

Page 18: ...ERJ6GEYJ103 0 1W 5 10K S M CARB R103 ERJ6GEYJ222 0 1W 5 2K2 S M CARB R104 ERJ6GEYJ332 0 1W 5 3K3 S M CARB R105 ERJ6GEYJ101 0 1W 5 100 S M CARB R106 ERJ6GEYJ681 0 1W 5 680 S M CARB R107 ERJ6GEYJ102 0 1W 5 1K S M CARB R111 ERJ6GEY0R00 0 1W 5 0 S M CARB R112 ERJ6GEYJ101 0 1W 5 100 S M CARB R113 ERJ6GEYJ223 0 1W 5 22K S M CARB R114 ERJ6GEYJ331 0 1W 5 330 S M CARB R115 ERJ6GEYJ331 0 1W 5 330 S M CARB R...

Page 19: ...01 1W 5 100 S M CARB R712 ERJ6GEYJ102 0 1W 5 1K SOLID R803 ERC12ZGK335D 0 5W 10 3M3 CARBON R805 ERD25TJ473 0 25W 5 47K CARBON R806 ERD25TJ100 0 25W 5 10 CARBON R807 ERD25TJ332 0 25W 5 3K3 CARBON R809 ERD25TJ681 0 25W 5 680 WOUND R810 ERW2PKR33 2W 20 R33 WOUND R811 ERW2PKR33 2W 20 R33 CARBON R812 ERD75TAJ825 0 75W 5 8M2 WOUND R813 ERF7ZK2R7 7W 20 2R7 CARBON R814 ERD25TJ473 0 25W 5 47K CARBON R815 E...

Page 20: ...B R2120 ERJ6GEYJ222 0 1W 5 2K2 S M CARB R2302 ERJ6GEYJ104 0 1W 5 100K S M CARB R2303 ERJ6GEYJ101 0 1W 5 100 S M CARB R2304 ERJ6GEYJ471 0 1W 5 470 S M CARB R2305 ERJ6GEYJ102 0 1W 5 1K S M CARB R2306 ERJ6GEYJ103 0 1W 5 10K S M CARB R2308 ERJ6GEYJ104 0 1W 5 100K S M CARB R2309 ERJ6GEYJ101 0 1W 5 100 S M CARB R2310 ERJ6GEYJ471 0 1W 5 470 S M CARB R2311 ERJ6GEYJ102 0 1W 5 1K S M CARB R2312 ERJ6GEYJ103 ...

Page 21: ...ILM C552 ECWH15H102J 1500V 1nF CERAMIC C557 ECKC2H471J 500V 470pF ELECT C558 ECA1HHG471E 50V 470µF ELECT C560 ECA2GHG2R2B 400V 470µF ELECT C561 ECA1EHG102B 25V 470µF CERAMIC C562 ECKC2H101J 500V 100pF ELECT C563 ECA2EHG220B 250V 20µF ELECT C564 ECEA2AU2R2 100V 20µF FILM C565 ECQP1H273J 100V 20µF CERAMIC C566 ECKC2H471J 500V 470pF ELECT C567 ECA1EHG102B 25V 470pF CERAMIC C568 ECKC2H471J 500V 470pF ...

Page 22: ...15 ECUV1H221JCX 50V 220pF S M CAP C2116 ECUV1H221JCX 50V 220pF S M CAP C2117 ECUV1H221JCX 50V 220pF S M CAP C2118 ECUV1H221JCX 50V 220pF S M CAP C2119 ECUV1H221JCX 50V 220pF S M CAP C2120 ECUV1H221JCX 50V 220pF ELECT C2121 ECA1CM100GB 16V 10µF ELECT C2122 ECJ2VF1H104Z 350V 100nF S M CAP C2123 ECUV1H221JCX 50V 220pF S M CAP C2124 ECUV1H070DTX 50V 70pF S M CAP C2125 ECUV1H470JCX 50V 47pF S M CAP C21...

Page 23: ... C551 ECKC3D561J 2KV 10µF FILM C555 ECWH15H822J 1500V 8 2nF FILM C556 ECQF4123JZH 400V 12nF FILM C559 ECWF2474JBB 500V 470nF ELECT C811 ECOS2GA151CB 400V 150pF DIFFERENCES FOR MODEL TX 25MD4 MECHANICAL PARTS BACK COVER 9 TKU8E00360 C R T 10 A59ECF50X41 CABINET 11 TKY8E180 CRT FIXING SCREW 12 VP17005 32 DEGAUSS COIL 13 TLK8E05138 E P C B 14 TNP8EE009AL MODEL LABEL 15 TQF8E2595 PANASONIC BADGE 16 TB...

Page 24: ...SISTOR Q908 2SA1535ARLB TRANSISTOR Q909 2SC3944ARLB TRANSFORMERS TRANSFORMER T801 ETS39AG1J7AD COILS COIL L552 ELH5L4105 COIL L554 ELC18B102L COIL L901 EXCELSA24T COIL L902 EXCELSA24T RESISTORS S M CARB JA3 ERJ6GEY0R00 0 1W 5 0 S M CARB JA2 ERJ6GEY0R00 0 1W 5 0 S M CARB JA1 ERJ6GEY0R00 0 1W 5 0 CARBON R363 ERD25TJ103 0 25W 5 10K CARBON R364 ERD25TJ103 0 25W 5 10K CARBON R365 ERD25TJ103 0 25W 5 10K...

Page 25: ... printing and are subject to change without notice REMARKS a Do not touch the hot part or the hot and cold parts at the same time as you are liable to a shock hazard b Do not short circuit the hot and cold circuits as electrical components may be damaged c Do not connect an instrument such as an oscilloscope to the hot and cold circuits simultaneously as this may cause fuse failure Connect the ear...

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Page 31: ... Q856 F9 D865 I9 IC1104 C9 Q855 J5 D864 I10 IC1103 F8 Q854 B4 D863 G9 IC1102 D10 Q853 B4 D862 N10 IC1101 D8 Q852 B5 D861 J9 IC1051 A10 Q850 F5 D860 I10 IC852 I10 Q701 J5 D859 H5 IC851 G5 Q552 N3 D858 E5 IC850 H4 Q551 K1 D857 E5 IC801 G2 Q503 I2 D855 F4 IC701 K5 Q451 F8 D854 G4 IC601 L7 Q394 K9 D853 H3 IC451 L5 Q305 K9 D852 I4 IC251 D6 Q303 K9 D851 I4 TP S Q302 J9 D850 H4 TPE14 M5 Q301 K9 D806 G2 T...

Page 32: ...354 A7 Q353 G6 Q352 F6 Q351 F6 DIODES D906 F1 D905 G4 D904 D3 D902 G4 D901 G3 D364 C9 D363 C8 D362 B9 D361 B7 D360 D8 D359 G6 D358 E7 D357 F7 D356 G7 D355 F7 D354 G7 TEST POINTS TPY6 B8 TPY5 D5 TPY4 E5 TPY3 F6 TPY2 E7 TPY1 G6 IC S IC351 E8 H G F E D C B A 1 2 3 4 5 6 7 8 9 ...

Page 33: ...G5 D355 F6 D356 G5 D357 G5 D358 F5 D359 G5 D360 C6 D361 B6 D362 D7 D363 D7 D364 D7 TEST POINTS TPY1 E4 TPY2 F5 TPY3 F4 TPY4 E3 TPY5 D3 TPY6 B6 TRANSISTORS Q351 G4 Q352 F4 Q353 G4 Q354 C7 I C S IC351 E6 1 2 3 4 5 6 7 A C B D E F G H ...

Page 34: ...30 NOTES ...

Page 35: ...there are a number of Service Aids which have been made available LUCI interface kit Linked Utility Computer Interface Part number TZS6EZ002 This contains interface and cables for connecting TV service connector and a PC as well as diagnostic software As new models are introduced upgrade software will become available VICI Visual Interactive Computer Information These C D s contain multimedia docu...

Page 36: ...This datasheet has been downloaded from www DatasheetCatalog com Datasheets for electronic components ...

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