background image

1

20GT-15

WARNING

The chassis in this receiver is partially hot. Use an isolation transformer between the line cord plug and power
receptacle, when servicing this chassis. To prevent electric shock, do not remove cover. No user –  serviceable
parts inside. Refer servicing to qualified service personnel.

SERVICE MANUAL

COLOUR TELEVISION

S30X520GT-15/

In the interests of user-safety (Required by safety regula-
tions in some countries) the set should be restored to its
original condition and only parts identical to those specified
be used.

MODEL

SERVICE MANUAL

COLOUR TELEVISION

MODEL 20GT-15

20GT-15

SHARP CORPORATION

20GT-15

Chassis No. UA-1

CONTENTS

Page

FEATURES ...................................................................................................................................................... 2

SPECIFICATIONS ........................................................................................................................................... 2

IMPORTANT SERVICE NOTES ...................................................................................................................... 3

ADJUSTMENT PRECAUTION ......................................................................................................................... 3

UA1 HOTEL MODE APPLICATION ................................................................................................................. 4

SERVICE MODE .............................................................................................................................................. 4

TROUBLE SHOOTING TABLE ...................................................................................................................... 18

SOLID STATE DEVICE BASE DIAGRAM ..................................................................................................... 20

CHASSIS LAYOUT ........................................................................................................................................ 21

BLOCK DIAGRAM ......................................................................................................................................... 22

WAVEFORMS ................................................................................................................................................ 25

SCHEMATIC DIAGRAM

DESCRIPTION OF SCHEMATIC DIAGRAM ................................................................................................. 26

INFRARED REMOTE CONTROL UNIT .................................................................................................... 27

TUNER ...................................................................................................................................................... 28

CRT UNIT .................................................................................................................................................. 29

MAIN UNIT ................................................................................................................................................ 30

PRINTED WIRING BOARD ASSEMBLIES .................................................................................................... 32

REPLACEMENT PARTS LIST

ELECTRICAL PARTS ................................................................................................................................ 37

SUPPLIED ACCESSORIES ...................................................................................................................... 41

PACKING PARTS ...................................................................................................................................... 41

CABINET PARTS ...................................................................................................................................... 41

Summary of Contents for 20GT-15

Page 1: ... condition and only parts identical to those specified be used MODEL SERVICE MANUAL COLOUR TELEVISION MODEL 20GT 15 20GT 15 SHARP CORPORATION 20GT 15 Chassis No UA 1 CONTENTS Page FEATURES 2 SPECIFICATIONS 2 IMPORTANT SERVICE NOTES 3 ADJUSTMENT PRECAUTION 3 UA1 HOTEL MODE APPLICATION 4 SERVICE MODE 4 TROUBLE SHOOTING TABLE 18 SOLID STATE DEVICE BASE DIAGRAM 20 CHASSIS LAYOUT 21 BLOCK DIAGRAM 22 WA...

Page 2: ...Receiving System CCIR PAL B G Tuner Ranges VHF Channels E2 48 25 MHz thru E12 224 25 MHz UHF Channels E21 471 25 MHz thru E69 855 25 MHz Dimensions Width 506 0 mm Height 476 0 mm Depth 479 0 mm Weight approx 17 2 kg Cabinet Material All Plastics FEATURES Ë Favourite Channel Ë Full Auto Channel Preset and Auto Channel Skip Ë 100 CH Program Memory Ë CATV Hyper Band Ready Used Frequency Synthesizer T...

Page 3: ...Receiving System CCIR PAL B G Tuner Ranges VHF Channels E2 48 25 MHz thru E12 224 25 MHz UHF Channels E21 471 25 MHz thru E69 855 25 MHz Dimensions Width 506 0 mm Height 476 0 mm Depth 479 0 mm Weight approx 17 2 kg Cabinet Material All Plastics FEATURES Ë Favourite Channel Ë Full Auto Channel Preset and Auto Channel Skip Ë 100 CH Program Memory Ë CATV Hyper Band Ready Used Frequency Synthesizer T...

Page 4: ...hardware is not lodged between the chassis and other metal parts in the receiver 2 Inspect all protective devices such as non metallic control knobs in sulating fishpapers cabinet backs adjustment and compartment cov ers or shields isolation resistor capacity networks mechanical insu lators etc ADJUSTMENT PRECAUTION This model s setting are adjusted in two different ways through the I2C bus contro...

Page 5: ...hardware is not lodged between the chassis and other metal parts in the receiver 2 Inspect all protective devices such as non metallic control knobs in sulating fishpapers cabinet backs adjustment and compartment cov ers or shields isolation resistor capacity networks mechanical insu lators etc ADJUSTMENT PRECAUTION This model s setting are adjusted in two different ways through the I2C bus contro...

Page 6: ...htness sharpness and tint function But after power off it will return to the initial setting You can t use Preset mode Fine tuning Skip mode System selection The others function is allowed to be used FORWARD CH DOWN key REVERSE CH UP key AGC GEOMETRIC MODE WHITE POINT ADJ MODE SUB ADJ MODE AGC GEOMETRIC MODE WHITE POINT ADJ MODE SUB ADJ MODE MISC OPTION MODE Y DELAY ADJ MODE IC OPTION MODE OFFSET ...

Page 7: ...CAL SCAN DISABLE VSD BLACK STRETCH BKS AUTO VOLUME LEVELING AVL FAST FILTER IF PLL FFI ENABLE VERTICAL GUARD EVG EHT TRACKING MODE EHT OVERSCAN SWITCH OFF OSO AUTO COLOUR LIMIT ACL FORCED COLOUR LIMIT FCO A NUMBER OF EXT AV SOURCE AV FM WINDOW SEVECTION FMWS SOUND MUTE BIT 0 SM0 SOUND MUTE BIT 1 SM1 THAI LANGUAGE THA ARABIC LANGUAGE ARA MALAY LANGUAGE MAL CHINESE LANGUAGE CHI FRENCH LANGUAGE FRE R...

Page 8: ... ADJUSTMENT 2 CDL DATA 2 FOR 20 21 ONLY 3 MANUAL CHANGE TO 0 4 MANUAL CHANGE TO 0 5 MANUAL CHANGE TO 0 6 IF 1 AV OUT SET TO 0 IF 2 AV OUT SET 1 7 MANUAL CHANGE TO 1 8 IF BILINGUAL MODEL PLEASE CHANGE TO 1 AFTER SHORT JA 122 JA 124 AND TURN ON THE MAIN POWER SWITCH READ DATA FROM EEPROM ADDRESS 00H 03H AND COMPARE TO THE LIST BELOW IF DIFFERENT INITIALIZE THE EEPROM ADDRESS DATA ADDRESS DATA 00H 55...

Page 9: ...uner antenna RF SWEEP 3 Adjust the sweep generator s to 80dBuV 4 Connect the response lead use LOW IMPEDANCE probe with wave detector see Fig 1 to the tuner s IF output terminal This terminal must have the probe alone connected 5 Set the RF AGC to 0 6 V with no saturation with the waveform 6 Adjust the tuner IF coil to obtain the waveform as shown in Fig 2 Note Be sure to keep the tuner cover in p...

Page 10: ...urity adjustment 1 Receive the Crosshatch Pattern signal 2 Using the remote controller call NORMAL mode Static convergence 1 Turn the 4 pole magnet to a proper opening angle in order to superpose the blue and red colours 2 Turn the 6 pole magnet to a proper opening angle in order to superpose the green colour over the blue and red colours Dynamic convergence 1 Adjust the convergence on the fringes...

Page 11: ...E SERVICE MODE ADJ I2C BUS CONTROL 1 Receive the WHITE Pattern with BURST signal 2 Press R C to set Picture NORMAL condition 3 Connect the DC miliammeter between the TP602 TP 603 4 Check Beam current should be around 1100µA 20 21 14 around 800µA 5 Set it to service mode and adjust the DRI GS DRI BS data to have a colour temperature of 12 300 K Note 6 Receive WHITE pattern WITH BURST signal and set...

Page 12: ...input terminal for each mode FUNCTION OPERATION CHECKING 1 VIDEO AUDIO ADJUSTMENT POINT ADJUSTMENT CONDITION PROCEDURE WAVEFORM OR OTHERS 1 NO CONTRAST Key 1 Receive Monoscope Pattern signal 2 Set P Mode to select CONTRAST 3 Press Volume Up Down key to check whether the CONTRAST effect is OK or not 2 COLOUR Key 1 Receive Color Bar signal 2 Set P Mode to select COLOUR 3 Press Volume Up Down key to ...

Page 13: ...the sound output is working properly or not 11 NOISE MUTE CHECKING 1 Receive PAL COLOUR BAR signal 2 Turn up the volume control to maximum make sure the sound is heard from the speakers Then put the unit in no signal state 3 Check the sound mute is effective 4 Finally turn sound level of CTV to minimum 12 OSD LANGUAGE QUANTITY CHECK Check OSD LANGUAGE quantity and type ...

Page 14: ...ET PAL 0F 08 08 00 0C 0F 0C 0C 0C 0C 0F 0C 0C 0C 08 08 04 04 08 00 3F 00 3F 00 3F 00 3F 00 3F 00 3F 00 3F 00 3F 00 3F 00 3F 00 3F 00 3F 00 3F 00 3F 00 3F 00 3F 00 3F 00 3F 00 3F 00 3F 00 3F 00 3F 00 FF 00 3F 00 3F 00 3F 00 3F 00 3F 00 3F 00 3F 00 0F 00 0F 00 0F 00 0F 00 0F 00 0F 00 0F 00 0F 00 0F 00 0F 00 0F 00 0F 00 0F 00 0F 00 0F 00 0F 00 0F 00 0F 00 0F 55 MICON DEFAULT 00 FF 4F 00 FF 43 00 FF A...

Page 15: ...R PART auto C SYS AFT S SYS TUNING FREQUANCY HIGHER PART TUNING FREQUANCY LOWER PART auto C SYS AFT S SYS TUNING FREQUANCY HIGHER PART TUNING FREQUANCY LOWER PART auto C SYS AFT S SYS TUNING FREQUANCY HIGHER PART TUNING FREQUANCY LOWER PART TUNING FREQUANCY LOWER PART auto C SYS AFT S SYS 00 FF 00 FF 00 00 00 00 00 02 00 00 01 00 01 00 07 00 01 80 00 00 00 00 FF 00 FF 00 FF 00 FF 00 FF 00 FF 00 FF...

Page 16: ... PART auto C SYS AFT S SYS TUNING FREQUANCY HIGHER PART TUNING FREQUANCY LOWER PART auto C SYS AFT S SYS TUNING FREQUANCY HIGHER PART TUNING FREQUANCY LOWER PART auto C SYS AFT S SYS TUNING FREQUANCY HIGHER PART TUNING FREQUANCY LOWER PART TUNING FREQUANCY LOWER PART auto C SYS AFT S SYS POS 29 POS 30 POS 31 POS 32 POS 33 POS 34 POS 35 POS 36 POS 37 TUNING FREQUANCY HIGHER PART TUNING FREQUANCY LO...

Page 17: ... 61 POS 62 POS 63 POS 64 TUNING FREQUANCY HIGHER PART TUNING FREQUANCY LOWER PART TUNING FREQUANCY HIGHER PART TUNING FREQUANCY HIGHER PART TUNING FREQUANCY LOWER PART auto C SYS AFT S SYS auto C SYS AFT S SYS auto C SYS AFT S SYS TUNING FREQUANCY LOWER PART auto C SYS AFT S SYS POS 65 POS 66 POS 67 MICON DEFAULT EEPROM RANGE WRITE CPU CHASSIS CHECK DATA CHECK TYPE CTV FINAL CHECK DATA CHECK TYPE ...

Page 18: ...OWER PART POS 82 POS 83 POS 84 POS 85 POS 86 POS 87 POS 88 POS 89 POS 90 TUNING FREQUANCY HIGHER PART TUNING FREQUANCY LOWER PART TUNING FREQUANCY HIGHER PART TUNING FREQUANCY HIGHER PART 18F TUNING FREQUANCY LOWER PART TUNING FREQUANCY LOWER PART auto C SYS AFT S SYS auto C SYS AFT S SYS auto C SYS AFT S SYS POS 91 POS 92 POS 93 POS 94 MICON DEFAULT EEPROM RANGE WRITE CPU CHASSIS CHECK DATA CHECK...

Page 19: ...U CHASSIS CHECK DATA CHECK TYPE CTV FINAL CHECK DATA CHECK TYPE LAST INITIAL SETTING DATA REMARK D7 D6 D5 D4 D3 DATA D2 D1 D0 SLAVE ADDRESS A0 00 FF A2 100 1FF EEPROM CHECK DATA LIST 6 ISSUED DATE TV MICOM ENGINEERING MANAGER CHIEF ENGINEER ISSUED DATE TV DESIGN ENGINEERING MANAGER CHIEF ENGINEER ISSUED DATE TV PRODUCTION ENGINEERING MANAGER CHIEF ENGINEER MODEL 1E0 1E1 1E2 1E3 1E4 1E5 1E6 1E7 1E8...

Page 20: ...rightness and Sound controls NO YES YES NO No snow noise Does signal appear at pin 40 of IC801 Noise increases but no signal is received Check the tuner supply voltage LB must be approx 5V BT must be approx 32V And CH preset data check Check the tuner AGC at TP201 Does signal appear at pin 38 of IC801 Check IC801 and related circuit Check IC PIF circuit and it s related circuit Check Q205 and Q203...

Page 21: ...ze are abnormal TROUBLE SHOOTING TABLE Continued NO SPECIFIC COLOUR Is some colour produced in B W broadcast reception Is the white balance properly adjusted Re adjust the white balance The picture colour is yellow The picture colour is magenta The picture colour is cyan Check Q871 Q883 and its adjacent circuits Check Q870 Q885 and its adjacent circuits Check Q872 Q887 and its adjacent circuits Ch...

Page 22: ...2SC1815 2SC2482 PST573J DX0386CE BASE COLLECTOR EMITTER BASE COLLECTOR EMITTER B C E KA7808 KA7805 1 2 3 ANODE RED CATHODE COMMON ANODE GREEN 1 2 3 SE115N STRF6654 TDA7056A PX0423CE 2SD2586 1 12 2R BR COLLECTOR COLLECTOR BASE EMITTER 2SC2735 JC COLLECTOR BASE EMITTER BASE EMITTER 1 3 TA48M033 1 3 5 2 4 9 TDA8357 TOP VIEW SIDE VIEW ...

Page 23: ...21 20GT 15 CHASSIS LAYOUT ...

Page 24: ...20GT 15 20GT 15 22 23 BLOCK DIAGRAM MAIN UNIT BLOCK DIAGRAM ...

Page 25: ...20GT 15 24 CRT BLOCK DIAGRAM ...

Page 26: ...25 20GT 15 WAVEFORMS ...

Page 27: ...ONNECTED WITH AC MAINS VOLTAGE WHENSERVICINGTHEAREA CONNECTANISOLATINGTRANS FORMER BETWEEN TV RECEIVER AND AC LINE TO ELIMINATE HAZARD OF ELECTRIC SHOCK NOTES 1 The unit of resistance ohm is omitted K 1000 ohms M Meg ohm 2 All resistors are 1 16 watt unless otherwise noted 3 All capacitors are µF unless otherwise noted P µµF VOLTAGE MEASUREMENT CONDITIONS 1 Voltage in parenthesis measured with no ...

Page 28: ...SCHEMATIC DIAGRAM A B C D E F G H I J 1 2 3 4 5 6 7 8 9 10 Infrared Remote Control Unit NOTE The parts here shown are supplied as an assembly but not independently Notes Unless specified the resistors are 1 10W 5 ...

Page 29: ...4 C208 102B C210 24p 3 R206 33k L206 D202 IT402 L205 R204 22 R203 82 C209 1 5p CH J201 0 J202 0 C312 472B R311 10k C212 0 9p 0 1 C261 102B L207 D203 IT402 R207 33k C211 24p 3 C122 102B C151 102B J301 0 C214 105p D109 IT402 C118 1p CH 0 1p D108 IT407 R144 47k C310 103B J302 0 C301 103B C353 102 R147 100 T301 R306 2k C119 103B D107 HSC277 L114 D301 1SS355 R117 47k R113 10k R120 10 L115 C120 103B C12...

Page 30: ...29 20GT 15 A B C D E F G H I J 1 2 3 4 5 6 7 8 9 10 CRT UNIT ...

Page 31: ...20GT 15 20GT 15 30 31 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 A B C D E F G H I J MAIN UNIT ...

Page 32: ...20GT 15 20GT 15 32 33 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 A B C D E F G H I J PRINTED WIRING BOARD ASSEMBLIES PWB A MAIN UNIT WIRING SIDE ...

Page 33: ...20GT 15 20GT 15 34 35 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 A B C D E F G H I J PWB A MAIN UNIT WIRING SIDE CHIP PARTS ...

Page 34: ...20GT 15 36 A B C D E F G H I J 1 2 3 4 5 6 7 8 9 10 PWB B CRT UNIT ...

Page 35: ... R DX0471CE AE D752 VHD1SS119 1 R 1SS119 AB D753 RH DX0471CEZZ R DX0471CE AE D758 RH DX0461CEZZ R DX0461CE AG D801 VHD1SS119 1 R 1SS119 AB D802 VHD1SS119 1 R 1SS119 AB D803 VHD1SS119 1 R 1SS119 AB D804 VHD1SS119 1 R 1SS119 AB D805 VHD1SS119 1 R 1SS119 AB D806 VHD1SS119 1 R 1SS119 AB D1001 RH PX0423CEZZ R LED AD D1004 VHD1SS119 1 R 1SS119 AB D1007 RH EX0867CEZZ R Zener Diode AC D1008 RH EX0867CEZZ ...

Page 36: ...K R 1000p 50V Ceramic AA C807 VCKYCY1HB102K R 1000p 50V Ceramic AA C808 VCEA0A1CW107M R 100 16V Electrolytic AC C809 VCKYCY1HF223Z R 0 022 50V Ceramic AB C810 VCKYCY1EF104Z R 0 1 25V Ceramic AA C811 VCEA0A1CW107M R 100 16V Electrolytic AC C812 VCFYFA1HA224J R 0 22 50V AB MetalIzed Polypro Film PACKAGED CIRCUIT PR701 RMPTP0001PEZZ R Packaged Circuit AN CRYSTAL X1001 RCRSB0281CEZZ R Crystal CRSB0281...

Page 37: ... VV3DB150J R 15 2W Metal Oxide AA R624 VRD RA2BE101J R 100 1 8W Carbon AB R625 VRS CY1JF184J R 180k 1 16W Metal Oxide AA R626 VRS CY1JF472J R 4 7k 1 16W Metal Oxide AA R628 VRD RM2HD470J R 47 1 2W Carbon AA C813 VCFYFA1HA224J R 0 22 50V AB MetalIzed Polypro Film C814 VCKYCY1HB471K R 470p 50V Ceramic AA C1001 VCEA0A0JW107M R 100 6 3V Electrolytic AB C1003 VCEA0A1CW106M R 10 16V Electrolytic AB C100...

Page 38: ...D150J R 15 1 2W Fuse ReisistorAC R705 VRD RA2BE122J R 1 2k 1 8W Carbon AA R706 VRD RM2HD152J R 1 5k 1 2W Carbon AA R707 VRS KT3LB473J R 47k 3W Metal Oxide AE R708 VRD RM2HD272J R 2 7k 1 2W Carbon AA R709 VRD RA2BE681J R 680 1 8W Carbon AA R710 VRN VV3ABR39J R 0 39 1W Metal Film AA R711 VRN VV3ABR33J R 0 33 1W Metal Film AA å R712 VRG PD2HD150J R 15 1 2W Fuse ReisistorAC R717 VRD RM2HD124J R 120k 1...

Page 39: ...BE102J R 1k 1 8W Carbon AA R894 VRD RA2BE102J R 1k 1 8W Carbon AA R898 VRD RA2BE471J R 470 1 8W Carbon AA R899 VRD RA2BE471J R 470 1 8W Carbon AA MISCELLANEOUS PARTS P851 QPLGN0641CEZZ R Plug 6 Pin AB P882 QPLGN0541CEZZ R Plug 5 Pin AB å SC881 QSOCV0840CEZZ R Socket 11 Pin AK SUPPLIED ACCESORIES ACCESSORIES RRMCG0025KJSA Infrared R C TiNS 0109KJZZ Instruction Book PACKING PARTS NOT REPLACEMENT ITE...

Page 40: ...ochigi 329 2193 Japan COPYRIGHT C 2000 BY SHARP CORPORATION ALL RIGHTS RESERVED No part of this publication may be reproduced stored in a retrieval system or transmitted in any form or by any means electronic mechanical photocopying recording or otherwise without prior written permission of the publisher TQ0856 S Mar 2000 Printed in JAPAN NA NS 20GT 15 ...

Reviews: