Panasonic TC 14A04A, TC 20A04A Diagram

Order DCS - JUN2004 - 003 - MS

Service Manual

GP3 CHASSIS

TC-14A04A TC-20A04A

Color Television

Specifications

TELEVISION

Power source Consumption Antenna input jack Color systems Tuning system Channel capability

Picture tube (Diagonal Visual) Audio output Video input jack Video Outlet Dimension (width, height, depth) Weight

Specifications are subject to change without notice. Weight and dimensions shown are approximate.

TC-14A04A

110/220 V AC, 50/60 Hz automatic switch

51 W

75 ohms - VHF/UHF/CATV

PAL-M/NTSC/PAL-N

F.S.T.

2 to 13 (VHF) 14 to 69 (UHF) 1 to125 (CATV)

Panablack 33 cm

3 W RMS

1 AV (back)

1 (back)

370 x 351 x 366 mm

9,6 kg

TC-20A04A

110/220 V AC, 50/60 Hz automatic switch

61 W

75 ohms - VHF/UHF/CA TV

PAL-M/NTSC/PAL-N

F.S.T.

2 to 13 (VHF) 14 to 69 (UHF) 1 to125 (CATV)

Panablack 48cm

3 W RMS

1AV (back)

1 (back)

502 x 455 x 471 mm

17 kg

Remote Control Transmiter: TNQ2B2902

Power Source 3V (2 AA type batteries) Infrared Length 9500 Å (Angstron) Number of Buttons 29 keys Dimensions (W x H x D) (54 x 27 x 135) mm

Panasonic

Supplied Accessories:

• 1 Remote Control Transmitter

• 1 300Ω/75Ω Balum

• 2 “AA” (or R6) batteries (1.5V; ABNT/IEC)

• 1 Internal antenna (for TC-14A04A only)

TC-14A04A / TC-20A04A

Important Safety Notice

Special components are used in this television set which are important for safety. These parts are identified on the schematic diagram by the symbol . It is essential that these critical parts are replaced with the manufacturers specified replacement parts to prevent X-ray radiation, shock, fire or other hazards. Do not modify the original design without manufacturers permission.



Contents

OPERATING INSTRUCTIONS ................................................................ 4

IC601 - PINOUT ................................................................................... 5

IC VOLTAGE T ABLES .......................................................................... 6

IC601 - BLOCK DIAGRAM ................................................................... 7

GP3 CHASSI FEATURE SUMMAR Y ..................................................... 8

THE DAC CONTROL FUNCTIONS FOR THE GP3 CHASSIS ................... 9

SERVICE MODE:

HOW TO ENTER IN THE SERVICE MODE ................................................. 9

TO EXIT SERVICE MODE AND RETURN TO NORMAL MODE ................... 9

ADJUSTMENTS:

CHK1, CHK2, CHK3 and CHK4 ADJUSTMENTS OPTIONS ............... 9, 10

1- VIF DETECTOR OUTPUT LEVEL CONFIRMATION ......................... 1 1

3- BUZZING CONFIRMATION (AUDIO CIRCUIT) ................................ 1 1

4- ANODE AND HEA TER VOL T AGE CONFIRMA TION ........................ 11

5- P AL COLOR OUTPUT LEVEL ADJUSTMENT ................................ 12

6- NTSC SUB-TINT CALIBRA TION ..................................................... 12

7- PROTECTION CIRCUIT (SHUTDOWN) OPERATION) ...................... 12

8- SUB-BRIGHTNESS AND SUB-CONTRAST CALIBRA TION ............. 13

9- FOCUS CALIBRA TION ................................................................... 13

10- COLOR PURITY ADJUSTMENT ...................................................... 13

11- WHITE QUALITY CALIBRA TION ..................................................... 14

12- CONVERGENCE CALIBRATION ...................................................... 14

14- CRT CUT OFF CALIBRATION ....................................................... 14

15- VERTICAL DEFLECTION CALIBRA TION ........................................ 15

16- WITHE BALANCE CALIBRA TION ................................................... 15

EEPROM MEMORY MAPS ................................................................... 16

SCHEMA TICS DIAGRAMS:

CRT PCB SCHEMA TIC DIAGRAM ........................................................ 18

MAIN PCB SCHEMATIC DIAGRAM ...................................................... 19

MAIN PCB LAYOUT ............................................................................ 20

SIGNAL WA VEFORMS ........................................................................ 21

EXPLODED VIEW ................................................................................. 25

General Guidelines

An Isolation Transformer should always be used during the servicing of a receiver whose chassis is not isolated from the AC power line. Use a transformer of adequate power rating as this protects the technician from accidents resulting in personal injury from electrical shocks. It will also protect the Receiver from being damaged by accidental shorting that may occur during servicing. When servicing, observe the original lead dress, especially in the high voltage circuit. Replace all damaged parts (also parts that show signs of overheating.) Always Replace Protective Devices, such as fishpaper, isolation resistors and capacitors, and shields after servicing the Receiver. Use only manufacturers recommended rating for fuses, circuit breakers, etc. High potentials are present when this Receiver is operating. Operation of the Receiver without the rear cover introduces danger from electrical shock. Servicing should not be performed by anyone who is not thoroughly familiar with the necessary precautions when servicing highvoltage equipment. Extreme care should be practiced when Handling the Picture Tube. Rough handling may cause it to implode due to atmospheric pressure (14.7 lbs per sq. in). Do not sick or scratch the glass or subject it to any undue pressure. When handling, use safety goggles and heavy gloves for protection. Discharge the picture tube by shorting the anode to chassis ground (not to the cabinet or to other mounting hardware). When discharging, connect cold ground (i.e. dag ground lead) to the anode with a well insulated wire or use a grounding probe. Avoid prolonged exposure at close range to unshielded areas of the picture tube to prevent exposure to X-ray radiation. The Test Picture Tube used for servicing the chassis at the bench should incorporate safety glass and magnetic shielding. The safety glass provides shielding for the tube viewing area against X-ray radiation as well as implosion. The magnetic shield limits X-ray radiation around the bell of the picture tube in addition to restricting magnetic effects. When using a picture tube test jig for service, ensure that the jig is capable of handling 31kV without causing X-ray radiation. Before returning a serviced receiver to the owner, the service technician must thoroughly test the unit to ensure that is completely safe to operate. Do not use a line isolation transformer when testing.

PARTS LISTS:

REPLACEMENT MECHANICAL P ARTS LIST ........................................ 26

REPLACEMENT ELECTRICAL PA RTS LIST .......................................... 27

- 2 -



Warning !

It is essential that these critical parts are replaced with the manufacturers specified replacement parts to prevent X-ray radiation, shock, fire or other hazards.

ABOUT LEAD FREE SOLDER (PbF)

This model uses lead free solder (PbF).

CAUTION:

TC-14A04A / TC-20A04A

• Pb free solder has a higher melting point than standard solder; typically the melting point is 50 - 70°F (300 - 400°C) higher. Please use a high temperature soldering iron. In case of the soldering iron with temperature control,please set it to 700 ± 20°F (370 ± 10°C).

• Pb free solder will tend to splash when heated too high (about 1 100°F/ 600°C). When soldering or unsoldering, please completely remove all of the solder on the pins or solder area, and be sure to heat the soldering points with the Pb free solder until it melts enough.

- 3 -

TC-14A04A / TC-20A04A

OPERATING INSTRUCTIONS

Terminal de

audio / video

de alimentación

Salida del cable

CANAL

VOL.

canales

selección

Botones de

secuencial de

() ()$4

Vista posterior de la televisión

PRE. TV/AV

Panasonic

Terminal de

la antena

Vista frontal de la televisión

Ubicación de los Controles (TC-14A04A / TC-20A04A)

Botón

TV/AV

Botón de

PRE AJUSTE

Sensor de

control remoto

Botón de

APAGADO

ENCENDIDO /

Luz indicadora

ACCESO DIRECTO

A LOS CANALES

WAKE-UP

(DESPERTADOR)

R-TUNE

CLOSED CAPTION

R-TUNEWAKE-UPTV/AV

123

456

789

ENCIENDE/APAGA

TIMER

SILENCIO

TV/AV

Ubicación de los Controles

LLAMADA

- 4 -

BOTONES DE

NORMALIZACIÓN

DIRECCIÕN DEL

MENÚ PRINCIPAL

MAIN MENU

PIC MENU

MENÚ DE

IMAGEM

SELECCIÓN

SECUENCIAL DE

CANALES

VOLUMEN

Panasonic

Complete Operating Instructions

TC-14A04A / TC-20A04A

IC601 - PINOUT

Symbol Pin Description

P3.1/ADC1 1 port 3.1 or ADC1 input P3.2/ADC2 2 port 3.2 or ADC2 input P3.3/ADC3 3 port 3.3 or ADC3 input VSSC/P 4 digital ground for m-Controller core and periphery P0.5 5 port 0.5 (8 mA current sinking capability for direct drive of LEDs) P0.6/CVBSTD 6 port 0.6 (8 mA current sinking capability for direct drive of LEDs) or Composite video input. A positive-going

1V (peak-to-peak) input is required VSSA 7 digital ground of TV-processor SECPLL 8 SECAM PLL decoupling VP2 9 2nd supply voltage TV-processor (+8V) DECDIG 10 supply voltage decoupling of digital circuit of TV-processor PH2LF 11 phase-2 filter PH1LF 12 phase-1 filter GND3 13 ground 3 for TV-processor DECBG 14 bandgap decoupling EWD 15 East-West drive output VDRB 16 vertical drive B output VDRA 17 vertical drive A output IFI N1 18 IF input 1 IFI N2 19 IF input 2 IREF 20 reference current input VSC 21 vertical sawtooth capacitor AGCOUT 22 tuner AGC output SIFIN1 23 SIF input 1 SIFIN2 24 SIF input 2 GND2 25 ground 2 for TV processor SNDPLL 26 narrow band PLL filter AVL/REF0/SNDIF (1) 27 Automatic Volume Levelling / subcarrier reference output / sound IF input AUDIO2 28 audio 2 input AUDIO3 29 audio 3 input HOUT 30 horizontal output FBISO 31 flyback input/sandcastle output DECSDEM 32 decoupling sound demodulator QSSO/AMOUT/ 33 QSS intercarrier output / AM output in stereo applications or deemphasis AUDEEM (1) (front-end audio out) / AM output in mono applications EHTO 34 EHT/overvoltage protection input PLLIF 35 IF-PLL loop filter SIFAGC 36 AGC sound IF INTCO 37 intercarrier output (from QSS or vision IF amplifier) IFVO/SVO (1) 38 IF video output / selected CVBS output VP1 39 main supply voltage TV processor CVBS1 40 internal CVBS input GND 41 ground for TV processor CVBS2 42 external CVBS2 input GND 43 ground for TV-processor CVBS3/Y 44 CVBS3/Y input C 45 chroma input WHSTR 46 white stretch capacitor CVBSO 47 CVBS output AUDOUT /AMOUT 48 audio output /AM audio output (volume controlled) SVM 49 scan velocity modulation output INSSW2 50 2nd RGB / YUV insertion input R2/VIN 51 2nd R input / V (R-Y) input / PR input G2/YIN 52 2nd G input / Y input B2/UIN 53 2nd B input / U (B-Y) input / PB input BCLIN 54 beam current limiter input BLKIN 55 black current input / V-guard input RO 56 Red output GO 57 Green output

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TC-14A04A / TC-20A04A

IC601 - PINOUT

Symbol Pin Description

BO 58 Blue output VDDA 59 analog supply of Teletext decoder and digital supply of TV-processor (3.3 V) VP E 60 OTP Programming Voltage VDDC 61 digital supply to core (3.3 V) OSCGND 62 oscillator ground supply XTALIN 63 crystal oscillator input XTALOUT 64 crystal oscillator output RESET 65 reset VDDP 66 digital supply to periphery (+3.3 V) P1.0/INT1 67 port 1.0 or external interrupt 1 input P1.1/T0 68 port 1.1 or Counter/Timer 0 input P1.2/INT0 69 port 1.2 or external interrupt 0 input P1.3/T1 70 port 1.3 or Counter/Timer 1 input P1.6/SCL 71 port 1.6 or I2C-bus clock line P1.7/SDA 72 port 1.7 or I2C-bus data line P2.0/TPWM 73 port 2.0 or Tuning PWM output P2.1/PWM0 74 port 2.1 P2.2/PWM1 75 port 2.2 P2.3/PWM2 76 port 2.3 P2.4/PWM3 77 port 2.4 P2.5/PWM4 78 port 2.5 SYNC_FILTER 79 CVBS (i.e. P0.6/CVBS) Sync filter input: This pin should be connected to VSSA via a 100 nF capacitor. P3.0/ADC0 80 port 3.0 or ADC0 input

IC VOLTAGE TABLES

Pin Voltage

1 3,3 2 21.2mV 32 40 5 2,56 6 97.5mV 70 8 2,3 98 10 5 11 3,3 12 3,9 13 0 14 4 15 11.6mV 16 1,3 17 1,3 18 1,9 19 1,9 20 3,9 21 3,8 22 146.7mV 23 181.3mV 24 181.3mV 25 0 26 1,3 27 2,5 28 3,7 29 3,7 30 0,6 31 0,5 32 2,3 33 2,8 34 1,6 35 1,5 36 198mV 37 0,4 38 2,7 39 8 40 3,6

IC601

Pin Voltage

41 0 42 3,8 43 0 44 3,3 45 0 46 3,6 47 2,9 48 3,5 49 4,4 50 2,5 51 2,7 52 2,7 53 2,7 54 2 55 5,3 56 3 57 3 58 3 59 3,3 60 0 61 3,3 62 28.5mV 63 1,9 64 1,9 65 0 66 3,3 67 105mV 68 4,7 69 5 70 3,2 71 2,3 72 3 73 55.9mV 74 0 75 0 76 3,7 77 0 78 0 79 0 80 0

IC451

Pin Voltage

1 0,3V 2 15,6V 3 -14V 4 -15,6V 5 67mV 6 16,5V 7 0,3V

IC1103

Pin Voltage

1 7,3mV 2 7,3mV 3 7,3mV 4 7,3mV 5 3,8V 6 3,8V 7 0,2V 85V

IC801

Pin Voltage

1 183V 2 3 22,7V 4 22,3V 5 96mV 6 1,5V 7 0,52V

IC1201

Pin Voltage

15V 2 6,4mV 3 1,27V 4 3,3V 5 6,4mV 65V

IC851

Pin Voltage

1 10,5V 2 10,5V 3 6,5V 4 4,3mV 5 6,3V 68V 75V

IC2301

Pin Voltage

1 11,22V 2 0,26V 3 6,6mV 4 0,23V 5 0,2V 6 1,46V 7 6,6mV 8 0,25V 9 50mV

X101

Pin Voltage

1 0,25V 2 0,25V 3 1,9V 4 1,9V

IC802

Pin Voltage

1 141V 2 8,5V 3 -8,7mV

T801

Pin Voltage

(V2) 1 22,5mV (V1) 2 23mV (P2) 5 180V (PT) 7 170V (P1) 8 168V (S6) 11 0,5V (S1) 12 0,2V (S2) 15 0,7V (S3) 17 0,2V

TPA10 142V TPA11 11,2V

Pin Voltage

1 10,4V 25V 3 -3,9mV

All voltage measurements were made in POWER ON mode, with 127V 60Hz power source and Color Bars Video Pattern.

IC880

- 6 -

IC601 - BLOCK DIAGRAM

TC-14A04A / TC-20A04A

+3.3 V

PWMS(4X)

I/O PORTS (4x)

ADC IN (4x)

VST OUT

SDASCL

LED OUT (2x)

VPE

RESET

AUDOUT

AUDIO3

AUDIO2

1/10 PAGE

MEMORY

C-BUS

TRANSCEIVER

VST PWM-DAC

80C51 CPU

ENHANCED

I/O PORTS

DISPLAY

TELETEXT/OSD

TELETEXT

ACQUISITION

CVBS

ROM/RAM

ROGOBO

BL B

COR

SYNC

BLUE STRETCH

CONTR/BRIGHTN

OSD/TEXT INSERT

DELAY LINE

BASE-BAND

BLKIN

BCLIN

CCC

WHITE-P. ADJ.

TINT CONTROL

SATURATION

BLACK STRETCH

RGB/YUV INSERT

WHITE STRETCH

EW GEOMETRY

V-DRIVE +

GEOMETRY

G/Y B/U BL

R/V

(EWD)

EHTO

VMOUT

HOUT V-DRIVE

(AVL)

(SNDIF)

AUDEEM

QSSO/AMOUT

AVL

SOUND PLL

DEEMPHASIS

AUDIO SWITCH

VOLUME CONTROL

AGC

QSS MIXER

QSS SOUND IF

AM DEMODULTOR

SIFIN

LUMA DELAY

REF

VISION IF

PLL DEMOD.

TUNERAGC

PEAKING

VMOUT

AGC/AFC

VIDEO AMP.

VIFIN

- 7 -

PAL/SECAM/NTSC

REF

VIDEO SWITCH

IFVO

TRAP

SOUND

DECODER

VIDEO IDENT.

VIDEO FILTERS

CVBS3/Y

CVBS2

CVBSO

LOOP

H-DRIVE

H-SHIFT

H-OSC. + PLL

H/V SYNC SEP.

+8V

TC-14A04A / TC-20A04A

CHASSIS GP3 FEATURE SUMMARY

MODELS : TC-14A04 e TC-20A04 SYSTEM : 3 systems (P AL-M/P AL-N/NTSC) (P AL-M 50hZ) POWER SOURCE : CA automatic power switching (1 10/220)V, 50/60Hz MEMORY : 125 positions TV TUNING RANGE : 181 channels (TV / CA TV) OSD LANGUAGE : Portuguese, Spanish and English AUDIO SYSTEM : Mono VERTICAL MAGNETIC FIELD : -0.1 ±0.03 COLOR TEMPERATURE : (High Light) x= 0.275±0.01, y=0.284 ±0.01, Y=150 (nit))

(Low Light) x= 0.273±0.01, y=0.283 ±0.01, Y=7.0 (nit)

REFERENCE VOLTAGE

CONTENTS TEST POINT

+B VOLTAGE

Buzzing confirmation

PAL color output

NTSC color output

Anode (EHT) voltage

MODEL

TPA10

TPA8 TPA9

TPA21

A22-3

ou TPA41

TPL2 TPL1 TPL1

CRT ANODE

ADJUSTMENT POINTS

MEMORY DATA

DA TA

VOLTAGE

140 ± 1,5V

8 ±1V 5 ±1V

175 ±1V

0.5 Vp-p

D C C

2.45 ±0.1Vo-p

2.45 ±0.5Vo-p

1.2 ±0.5Vo-p

24.5 +0.7 (Kv)

24.5 -1.5 (kV)

TC-14A04A

TC-20A04A

[A]=C1H , [B]=00H , [C]=00H , [D]=33H , [E]=00H , [F]=20H , [G]=00H , [H]=01H [A]=C1H , [B]=00H , [C]=00H , [D]=33H , [E]=00H , [F]=20H , [G]=00H , [H]=01H

- 8 -

TC-14A04A / TC-20A04A

THE DAC CONTROL FOR GP3 CHASSIS FUNCTIONS AND ADJUSTMENTS

HOW TO ENTER IN THE SERVICE MODE:

1- Set the “OFF TIMER” to 30 minutes. 2- Press simultaneously RECALL key on the remote control and VOL(-) button on the unit.

After a couple of seconds, the expression “CHK” should appear on the right superior side of the screen. (T o change the memory data, press MUTE and VOLUME(_) simultaneously while the OSD is still on CHK1 mode. Key “4” moves forward in the memory , and key “3” moves back in the memory

Note: T o alter from CHK1 mode to CHK2, CHK3 or CHK4 modes, press key “2” to move forward and the key “1” to

move back, as illustrated below.

NORMAL MOD E

Turn off

CHK1

OPTION CODE

SETTING

“2”

“

”

SERVICE MODE

“2”“

CHK2 CHK 3 CHK4

VCJ

ADJUSTMENT

PINCUSHION

ADJUSTMENT

”“

“

TO EXIT SERVICE MODE AND RETURN TO NORMAL MODE:

Press the “NORMAL” key on the remote control unit or turn off the TV.

CHK1 - OPTIONS

On CHK1 mode, it is possible to adjust the options below:

“4”

OPTION1 OPTION1 OPTION2 OPTION2

DIGITO MSB DIGITO LSB DIGITO M SB DIGI TO LSB

OPTION3

DIGITO MSB

OPTION5

DIGITO MSB

OPTION7

DIGITO MSB

ááá

“3”

“4”

OPTION3

DIGITO LSB

“3”

“4”

OPTION5

DIGITO LSB

“3”

“4”

OPTION8

DIGITO LSB

“3”

“4”

“3”

“4”

OPTION4

DIGITO MSB

“3”

“4”

OPTION6

DIGITO MSB

“3”

“4”

OPTION1

DIGITO MSB

“3”

“4”

“3”

“4”

OPTION4

DIGITO LSB

“3”

“4”

OPTION6

DIGITO LSB

“3”

“4”

“3”

“4”

“3”

å ááá

Note:

To select an option, type “4” to move forward and “3” to move back. After having selected the desired option, adjust it by pressing the “VOL(_)” or “VOL(+)” keys. Press “0” to memorize the adjustment.

”

WHITE BALANCE

ADJUSTMENT

”

CHK1 mode adjustments

On CHK1 mode it is possible to adjust the items of the table shown here.

Note:

T o select an item, type “4” to move forward and “3” to move back. After having selected the desired option, adjust it by pressing the “VOL(_)” or “VOL(+)” keys. Press “0” T o memorize the adjustment.

- 9 -

CHK1 mode table

Standard values

TC-14A04A

OPTION1 OPTION2 OPTION3 OPTION4 OPTION5 OPTION6 OPTION7 OPTION8

00 00 00 33 00 20 00 01

TC-20A04A

00 00 00 33 00 20 00 01

TC-14A04A / TC-20A04A

ADJUSTMENTS

CHK2 mode adjustments

On CHK2 mode it is possible to adjust the items of the table shown here.

Note:

CHK3 mode adjustments

On CHK3 mode it is possible to adjust the items of the table shown here.

Note:

CHK4 mode adjustments

On CHK4 mode it is possible to adjust the items of the table shown here.

Note:

CHK2 mode table

RF AGC CONT COL S-COL TINT S-TINT BRT

CHK3 mode table

Standard values

V-SLOPE 60HZ V-SHIFT 60HZ V-AMP 60HZ H-SHIFT 60HZ S-CORR 60HZ

CHK4 mode table

Standard values

R-CUT G-CUT BRT S-BRT CONT S-CONT R-DR G-DR B-DR RGB CON

Standard values

TC-14A04A

100

50 34 50 30 30

TC-14A04A

35 36 44 18 28

TC-14A04A

26 25 50 28

100

21 28 31 33

TC-20A04A

100

50 34 50 30 30

35 36 44 18 28

26 25 50 28

100

21 28 31 33

ADJUSTMENTS

TEST AND MEASUREMENT EQUIPMENTS

T o execute all these electrical adjustments, the following equipment are required:

• Dual-Trace Oscilloscope Voltage Range: 0.001 V to 50 V/Div. Frequency Range: DC to 50 MHz Probes: 10:1, 1:1

• NTSC Video Pattern Generator

• DVM (Digital V olt Meter)

• MTS/SAP Signal Generator

• (TV Multi-Channel Sound Modulator (U.S.A.))

• Plastic Tip Driver and Non-Metal Driver

• Isolation Transformer (V ariable)

• Degaussing Coil

• White Pattern Generator

• Audio Generator

- 10 -

ADJUSTMENTS

ITEM / PREPARATION PROCEDURE

TC-14A04A / TC-20A04A

1- RF AGC ADJUSTMENT

1. Supply a color bar pattern and adjust the RF input signal of 69 dB µV (75Ω opened channel 07 RF freq.: 175.25

MHz).

2. Connect the digital multimeter in TPA15.

2- VIF DETECTOR OUTPUT LEVEL

CONFIRMATION

3- BUZZING CONFIRMATION

(AUDIO CIRCUIT)

1. Connect the oscilloscope with a 7kHz filter between A22-

2 and A22-3 speakers terminals .

2. Adjust the sound to maximum.

3. Adjust AVL: OFF

ADJUSTMENT:

1. Select RF AGC on CHK2 service mode.

2. Adjust "RF AGC" by pressing VOL(+) or (-) until obtaining

2.2±0.1V in TPA15.

3. Increase the input level by +2 dB and confirm that the voltage decreases in TPA15.

CONFIRMATION:

1. Install the chassis in the VIF calibration JIG and tune in a

63 dBU colorbar pattern (75Ω opened).

2. Connect the oscilloscope in TPA31.

3. Confirm that the output video sign is 1.05 ± 0.15 Vp-p in

TPA 31.

CONFIRMATION:

1. Supply a colorbar signal with local frequency adjusted

and the AFC ON (Channel with sound bearer and without modulation).

2. Assure that the width in the buzzing waveform is smaller

than 500 m Vp-p.

4- ANODE AND HEATER VOLTAGE CONFIRMATION

1. Supply a crosshatch signal.

2. Adjust the current beam to zero. (0 beam).

3. Adjust “SCREEN VR” and “CONTRAST” to minimum. Nota:

(When using a high voltage meter resistive type, it is necessary to use an electrostatic meter type to verify the values)

smaller than 500 m Vp-p

CONFIRMATION

1. Connect a voltage meter between TPA10 and ground.

Confirm that the voltage +B is within a range of 140.5V±

1.5V

2. Connect a high frequency voltage meter (VRMS) among

the heater, and confirm that the voltage is as below:

14" SAMSUNG A34KQW42X 6,30 ± 0,25 Vrms 14" PHILIPS A34EAK01X 6,15 ± 0,25 Vrms 20" SAMSUNG A48KRDB89X 6,30 ± 0,25 Vrms 20" PHILIPS A48EAK01X 6,15 ± 0,25 Vrms

3. Connect the high voltage meter in the CRT anode pin,

and confirm that the high voltage is within [A] range.

CRT [A]

14” 25,2 ~ 23,0 20” 27,2 ~ 25,0

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