Panasonic TX-29PN1, TX-28PN1 Schematic

ORDER No. PCZ0504048C2

Service Manual

Colour Television

TX-29PN1D, TX-29PN1F,

TX-29PN1P,

TX-28PN1D, TX-28PN1F,

TX-28PN1P,

GP4L Chassis

SPECIFICATIONS

(Information in brackets [ ] refers to models 28”)

Power Source: 220-240V a.c., 50Hz

Power Consumption: 68W [65W]

Stand-by Power Consumption: 1W

Aerial Impedance: 75Ω unbalanced, Coaxial Type

Receiving System: PAL-I, B/G, D/K, PAL-525/60

SECAM B/G, D/K, L/L’ M.NTSC (AV only) NTSC (AV only)

Receiving Channels:

VHF E2-E12 VHF H1-H2 (ITALY) VHF A-H (ITALY) VHF R1-R2 VHF R3-R5 VHF R6-R12 UHF E21-E69 CATV (S01-S05) CATV S1-S10 (M1-M10) CATV S11-S20 (U1-U10) CATV S21-S41 (HYPERBAND)

Intermediate Frequency: Video/Audio

Video 38,9MHz, 33,9MHz Sound 33,4MHz (B/G), 33,16MHz (A2)

33,05MHz (NICAM B/G,D/K,L) 32,4MHz (D/K),32,66MHz (CZ STEREO) 40,4MHz (L’), 39,75MHz (L’NICAM)

Colour 34,47MHz (PAL)

34,5MHz, 34,65MHz (SECAM) 38,3MHz, 38,15MHz (SECAM L’)

AV2 IN Video (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) 1V p-p 75Ω

Audio (21 pin) 500mV rms 1kΩ

AV3 IN Audio (RCAx2) 500mV rms 10kΩ

Video (RCAx1) 1V p-p 75Ω

High Voltage: 31kV ± 1kV

Picture Tube: A68EPD10X30 68cm

[W66MAF185X03 66cm]

Audio Output: 2x5W RMS, 2x10W MPO,

8Ω impedance

Headphones: 8Ω Impedance

Accessories supplied : Remote Control

2 x R6 (UM3) Batteries

Dimensions:

Height: 584mm [528mm] Width: 668mm [698mm] Depth: 500mm [490mm]

Net weight: 40kg [35,5kg]

Terminals:

AV1 IN Video (21 pin) 1V p-p 75Ω

Audio (21 pin) 500mV rms 10kΩ RGB (21 pin) 0,7V p-p 75Ω

AV1 OUT Video (21 pin) 1V p-p 75Ω

Audio (21 pin) 500mV rms 1kΩ

Note: Specifications are subject to change without notice. Weights and dimensions shown are approximate.

CONTENTS

SAFETY PRECAUTIONS ......................................................................................................................................................... 2

SERVICE HINTS ...................................................................................................................................................................... 3

ADJUSTMENT PROCEDURE AND SELF-CHECK.................................................................................................................. 4

WAVEFORM PATTERN TABLE............................................................................................................................................... 5

ALIGNMENT SETTINGS .......................................................................................................................................................... 6

BLOCK DIAGRAMS.................................................................................................................................................................. 7

PARTS LOCATION................................................................................................................................................................. 10

REPLACEMENT PARTS LIST................................................................................................................................................ 11

SCHEMATIC DIAGRAMS....................................................................................................................................................... 19

CONDUCTOR VIEWS ............................................................................................................................................................ 22

SAFETY PRECAUTION

GENERAL GUIDE LINES

1. It is advisable to insert an isolation transformer in the a.c. supply before servicing a hot chassis.

2. When servicing, observe the original lead dress in the high voltage circuits. If a short circuit is found, replace all parts that have been overheated or damaged by the short circuit.

3. After servicing, see that all the protective devices such as insulation barriers, insulation papers, shields and isolation R-C combinations are correctly installed.

4. When the receiver is not being used for a long period of time, unplug the power cord from the a.c. outlet.

5. Potentials as high as 32kV are present when this receiver is in operation. Operation of the receiver without the rear cover involves the danger of a shock hazard from the receiver power supply. Servicing should not be attempted by anyone who is not familiar with the precautions necessary when working on high voltage equipment. Always discharge the anode of the tube.

6. After servicing make the following leakage current checks to prevent the customer from being exposed to shock hazard.

LEAKAGE CURRENT COLD CHECK

1. Unplug the a.c. cord and connect a jumper between the two prongs of the plug.

2. Turn on the receiver’s power switch.

3. Measure the resistance value with an ohmmeter, between the jumpered a.c. plug and each exposed metallic cabinet 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 a.c. cord directly into the a.c. outlet. Do not use an isolation transformer for this check.

2. Connect a 2kΩ 10W resistor in series with an exposed metallic part on the receiver and an earth, such as a water pipe.

3. Use an a.c. voltmeter with high impedance to measure the potential across the resistor.

4. Check each exposed metallic part and check the voltage at each point.

5. Reverse the a.c. plug at the outlet and repeat each of the previous measurements.

6. The potential at any point should not exceed 1,4 Vrms. In case a measurement is outside the limits specified, there is a possibility of a shock hazard, and the receiver should be repaired and rechecked before it is returned to the customer.

HOT CHECK CIRCUIT

a.c. VOLTMETER

2kΩ 10 Watts

TO INSTRUMENT'S EXPOSED METALLIC PARTS

Fig. 1.

X-RADIATION WARNING

1. The potential sources of X-Radiation in TV sets are the high voltage section and the picture tube.

2. When using a picture tube test jig for service, ensure that the jig is capable of handling 32kV without causing X-Radiation.

NOTE: It is important to use an accurate periodically

calibrated high voltage meter.

1. Set the brightness to minimum.

2. Measure the high voltage. The meter should indicate:

31kV ± 1kV. If the meter indication is out of tolerance, immediate service and correction is required to prevent the possibility of premature component failure.

3. To prevent any X-Radiation possibility, it is essential to use the specified tube.

WATER PIPE

(

EARTH)

SERVICE HINTS

How to remove the rear cover

1. Remove the 10 screws as shown in Fig.2.

SCREWS

LOCATION OF CONTROLS

SCREWS

Fig. 2

L-Board

D-Board

Focus

Fig.3

Screen

ADJUSTMENT PROCEDURE

Item / Preparation Adjustments +B SET-UP

1. Receive a Window pattern.

2. Set the controls :

Brightness Minimum

Contrast Minimum

Volume Minimum

Confirm the following voltages:

TPD11 12,3 ± 0,5V TPD21 9,4 ± 0,5V

TPD12 3,3 ± 0,15V TPD23 138 ± 1,5V TPD13 5 ± 0,25V TPD121 205 ± 10V TPD16 8 ± 0,3V TPD122 17,2 ± 1V TPD17 3,3 ± 0,15V TPD123 -11,6 ± 1V TPD20 1,8 ± 0,1V TPD124 13,6 ± 1V

TPL5 6,3 ± 0,3V

Audio 5W

13,5 ± 0,5V 5,7 ± 0,3V

Audio MIN

Normal mode

Standby mode

CUT OFF / Ug2 Test

1. Receive a Window pattern.

3. Set: Colour 50% Brightness 50% Contrast 100%

To adjust Cutoff connect an oscilloscope to the Blue cathode. Adjust the screen VR until the black level is 160V ± 2V.

Black Level

160V ± 2V

GND

SELF CHECK

Self-check is used to automatically check the bus lines and hexadecimal code of the TV set.To enter Self-Check mode, press the STATUS button on the remote control and at the same time press the down (-/v) button on the customer controls at the front the TV set. To exit Self Check, switch off the TV set at the power button.

E2 O.K. TUN O.K. DDP O.K. MSP O.K. VSP O.K. DPL ---

VSW O.K. MAS ---

VCTi F1

TX-29PN1D

OPTION 1 0F OPTION 2 00 OPTION 3 A0 OPTION 4 11 OPTION 5 00 OPTION 6 35 OPTION 7 7F OPTION 8 D4 OPTION 9 00 OPTION 10 00 OPTION 11 11 OPTION 12 00 OPTION 13 88

CHECK E1

TX-29PN1F TX-29PN1P

0F 00

0 11 00 35 7F 54 00 00 11 00 88

TX-28PN1D

0F 00 B0 11 00 35 7F D4 00 00 11 00 88

TX-28PN1F TX-28PN1P

0F 00 B0 11 00 35 7F 54 00 00 11 00 88

If the CCU ports have been checked and found to be incorrect or not located then " - - " will appear in place of "O.K.".

WAVEFORM PATTERN TABLE

CONDITIONS: Contrast: MAX, Brightness: MID, Colour: MID, Sharpness: MID

R,G,B /IC601/: Receive a window pattern.

ALIGNMENT SETTINGS

(The figures below are nominal and used for representative purposes only.)

1. Set the Bass to maximum position, set the Treble to minimum position, set the Volume to minimum then press the down button (-/v) on the customer controls at the front of the TV and at the same time press the INDEX button on the remote control, this will place the TV into the Service Mode 1.

2. Press the RED / GREEN buttons to step up / down through the functions.

3. Press the YELLOW / BLUE buttons to alter the function values.

4. Press the OK button after each adjustment has been made to store the required values.

5. To exit the Service Mode, press the "N" button.

Alignment Function

EAROM copy TV/EXT ---

FLASH program copy EXT -> TV ---

Horizontal Position

Vertical Position

Horizontal Amplitude

Vert. Amplitude

EW-amplitude

Lower Corner

Trapezium-comp

Upper Corner

Note: All setting values are approximate

Setting indication

H-Pos

-4

V-Pos

H-Amp

V-Amp

-15

EW-Amp 1

- 30

Lower Corner

Trapez 1

Upper Corner

Settings / Special features

Optimum setting.

Vertical Linearity

Vertical Symmetry

Angle

Bow

DVCO

Highlight Lowlight

Sub-Brightness

V-Lin

V-Sym

-6

Angle

Bow

DVCO

High 0374 0318 0335 Low 0207 0331 0256

Sub-Brightness

-10

Optimum setting.

Receive a PAL Colour Bar Pattern. For DVCO alignment press "Blue" button, wait until the figure colour is changed from red to black colour.

Optimum setting.

D353

D352

Q354

CRT

R L

Q353

Q352

Q351

R 9

B 7

G 8

IC351

1542 3

L-BOARD

4 R IN

2 L IN

IC2301

LA42072-E

UDIO OUTPUT

R OUT(1) 9

L OUT(1) 11

R OUT(0) 8

L OUT(0) 12

JK3201

2 R IN

6 L IN

1 R OUT

3 L OUT

HEADPH

FRONT AV3 TERMINAL

Q308

Q309

Q304 Q307

Q306

Q305

Q301

Q302

Q303

5 SPEAKR

4 SPEAKL

82 SENSE

71 BOUT

72 GOUT

73 ROUT

VIDEO & STEREO AUDIO & DEFLECTION BLOCK DIAGRAM

TUNER

AV2_IR 4

AV2_I L 11

UDIO SWITCH

IC2401

TC74HC4066AF

10 AV12_IL

AV12_IL 12

1 AV1_IR

2 AV12_IR

AV12_IR 13

16 IF1

17 IF2

XF101

AV2 21 PIN SCART

TC74HC4066AF

15 C_IN

19 VIDEO OUT

20 VIDEO IN

8 AV1_IL

AV2_OR 9

AV3_IR 11

AV3_V 38

AV3_IL 10

IC601

VCT4973FPZF1

MICROPROCESSOR

61 HFLB

60 H-OUT

Q501

85 V+

83 EW

AV2_OL 8

AV2_C 34

84 V-

59 VPROT

Q702

Q606

AV1_OR 7

AV1_OL 6

B_IN 30

AV2_OUT 41

AV2_CVBS 35

G_IN 31

R_IN 32

AV1_OUT 40

AV1_CVBS 33

VFLB

D601

Q701

Q703

T551

Q605

IC451

VERTICAL

6 L IN

2 R IN

1 R OUT

3 L OUT

7 B IN

11 G IN

15 R IN

19 VIDEO OUT

20 VIDEO IN

AV1 21 PIN SCART

13 4

DEFLECTION

T553

D-BOARD

Q551

DIODE

MODULATOR

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