Sharp 28JW-74H Service Manual
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Sharp 28JW-74H Service Manual

Sharp 28JW-74H Service Manual

Pal i system colour television
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8
ELECTRICAL SPECIFICATIONS ................... 3
IMPORTANT SERVICING NOTES ................. 4
CONTROLS & TERMINALS ........................... 5
ADJUSTMENT PROCEDURES ...................... 7
POSTCODE RESET ...................................... 11
LED FLASHING CODES ............................... 12
PRINTED WIRING BOARDS ........................ 13
SHARP CORPORATION
SERVICE MANUAL
PAL I SYSTEM COLOUR TELEVISION
MODEL
In the interests of user safety (required by safety
regulations in some countries) the set should restored
to its original condition and only parts identical to
those specified should be used.
CONTENTS
CHASSIS LAYOUT ......................................... 19
ICs ADDITIONAL INFORMATION .................. 21
SCHEMATIC DIAGRAMS ............................... 36
TROUBLESHOOTING TABLES ..................... 49
PARTS LISTING ............................................. 52
SOURCE OF DOCUMENTATION .................. 60
1
SE0028JW74H00
Issued:21
GA-20
CHASSIS
28JW-74H
This document has been published to
be used for after sales service only.
28JW-74H
June 2002
st

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  • Page 1: Table Of Contents

    28JW-74H SERVICE MANUAL SE0028JW74H00 Issued:21 June 2002 GA-20 CHASSIS PAL I SYSTEM COLOUR TELEVISION 28JW-74H MODEL In the interests of user safety (required by safety regulations in some countries) the set should restored to its original condition and only parts identical to those specified should be used.
  • Page 2 28JW-74H SERVICE MANUAL UPDATE LOG SHEET Technical Report No. Application Cause / Solution Part No. Page No. Technical Bulletin No. Data /Serial No. Use this page to keep any special servicing information as Technical Report (Bulletin), Technical Information, etc. If only part number changes are required, just change part number directly the part number in the Parts Listing Section.

  • Page 3: Electrical Specifications

    28JW-74H ELECTRICAL SPECIFICATIONS •Focus ....... High Bi-Potential Electrostatic •Power Input ....220V-240 Volts AC 50Hz •Sweep Deflection ........Magnetic •Power Consumption •Picture Intermediate frequency....38.9MHz Normal Operation (Method IEC60107) .... 80W Stand-by Operation ..........3W •Sound Carrier Trap........32.9MHz •Adjacent Sound Carrier Trap ....40.9MHz •Audio Power Output Rating (MPO) / Impedance...

  • Page 4: Important Servicing Notes

    28JW-74H IMPORTANT SERVICING NOTES Only qualified service personnel are allowed to carry out maintenance and repair of this receiver. Servicing of High Voltage System and CRT It is important that the static charge is removed from the high voltage system when carrying out work on the receiver.

  • Page 5: Controls & Terminals

    28JW-74H CONTROLS & TERMINALS I FRONT TV Main power button Power indicator Remote control sensor Volume DOWN button Volume UP button Channel DOWN button 3 4 5 6 7 Channel UP button Door HOW TO OPEN THE DOOR Press the top of the door, opening it slightly hook your finger inside and pull open.

  • Page 6: Remote Control

    28JW-74H REMOTE CONTROL 1. Stand-by button (TV) Video 2. Power button (VCR) 3. 0 ~ 9 digit buttons 4. Flash back button Teletext 5. GREEN button 6. RED button 7. Volume DOWN button 8. MENU button Teletext 9. REVEAL button 10.

  • Page 7: Adjustment Procedures

    28JW-74H ADJUSTMENT PROCEDURES All adjustments to this chassis, except for focus, are carried out in the Service Mode. Service Mode The Service Mode is provided to enable the engineer to correctly set up the receiver to the CRT fitted in the set.
  • Page 8 28JW-74H Horizontal Vertical • Horizontal Shift • Vertical Amplitude • E-W Width • Vertical Shift • Pin Phase • Vertical Bow • Pin Amp • Vertical Angle • Corner Amplitude • S Correction • Corner Symmetry • Vertical Linearity Just in case the TV set requires a full geometry adjustment, please proceed first with Vertical according to the above order, and after that, adjust Horizontal according to the above order.
  • Page 9 28JW-74H Corner Symmetry Adjust the Corner Symmetry so that the picture is centred. The effect of this adjustment is shown in figure 7. Note: This adjustment affects to upper and lower sides. • When the volume up button is pressed, side pincushion changes from barrel shape to pincushion.
  • Page 10 28JW-74H • When the volume down button is pressed the top and bottom scanning decreases and the centre scanning increases. • Press the stand-by button on the remote control to store. Vertical Shift Adjust the Vertical Shift so that the picture is centred.

  • Page 11: Postcode Reset

    5. If another NVM value has to be changed, use the channel down button to select the page or position and repeat as necessary. Note: DO NOT change any NVM data, unless you have been advised to do so by a Sharp representative. If data is incorrectly changed, serious damage may occur to the receiver.

  • Page 12: Led Flashing Codes

    28JW-74H Contrast Adjustments Three types of contrast levels can be varied as listed below: • TELETEXT MIX MODE CONTRAST • TELETEXT CONTRAST • OSD CONTRAST Use the volume up/down buttons to adjust to a suitable level, then. It is not necessary to press the stand-by button to store, data are memorized by exiting the Service Mode.

  • Page 13: Printed Wiring Boards

    28JW-74H FB218WJN2 CRT UNIT PWB. Component side. FB218WJN2 CRT UNIT PWB. Copper side.
  • Page 14 28JW-74H FB217WJN2 MOTHER UNIT PWB. Component side.
  • Page 15 28JW-74H FB217WJN2 MOTHER UNIT PWB. Component side.
  • Page 16 28JW-74H FB217WJN2 MOTHER UNIT PWB. Copper side.
  • Page 17 28JW-74H FB217WJN2 MOTHER UNIT PWB. Copper side.
  • Page 18 28JW-74H FB219WJN1 CONTROL UNIT PWB Component side Copper side...

  • Page 19: Chassis Layout

    28JW-74H CHASSIS LAYOUT PWB A (Mother Unit, FB217N2).
  • Page 20 28JW-74H PWB B CHASSIS LAYOUT (CRT SOCKET UNIT, FB218N2). PWB C CHASSIS LAYOUT (FRONTAL POWER-CONTROL UNIT, FB219N1).

  • Page 21: Ics Additional Information

    28JW-74H ICs ADDITIONAL INFORMATION TDA9885 (IC201) QUICK REFERENCE DATA SYMBOL PARAMETER CONDITIONS MIN. TYP. MAX. UNIT supply voltage notes 1 and 2 supply current Video part −1 dB video at output − µV VIF input voltage sensitivity i(VIF)(rms) (RMS value) −...
  • Page 22 28JW-74H TDA9885 (IC201) SYMBOL PARAMETER CONDITIONS MIN. TYP. MAX. UNIT −3 dB AF bandwidth − without de-emphasis; AF(−3dB) dependent on FM-PLL filter − weighted signal-to-noise ratio of FM: 27 kHz FM deviation; W(AF) 50 µs de-emphasis; audio signal vision carrier unmodulated −...
  • Page 23 28JW-74H TDA9885 (IC201) BLOCK DIAGRAM handbook, full pagewidth...
  • Page 24 28JW-74H TDA9885 (IC201) PINNING SYMBOL DESCRIPTION TDA9886T TDA9885T TDA9885HN TDA9886TS TDA9885TS VIF1 VIF differential input 1 VIF2 VIF differential input 2 − − n.c. not connected output port 1; open-collector FMPLL FM-PLL for loop filter DEEM de-emphasis output for capacitor...
  • Page 25 28JW-74H TDA7480 (IC1301,IC1302) TDA7480 ABSOLUTE MAXIMUM RATINGS Symbol Parameter Value Unit ±20 DC Supply Voltage Storage and Junction Temperature –40 to 150 °C Maximum Voltage Across VFREQ (Pin 9) FREQ Operating Temperature Range -20 to 70 °C ±1.8 Maximum ESD on Pins Rth with "on board"...
  • Page 26 28JW-74H TDA7480 (IC1301,IC1302) = ±14V; R ELECTRICAL CHARACTERISTICS (Refer to the test circuit, V = 8Ω; R = 50Ω; = 12KΩ; Demod.. filter L = 60µH, C = 470nF; f = 1KHz; T = 25°C unless otherwise specified.) Symbol Parameter Test Condition Min.
  • Page 27 28JW-74H MSP3411G (IC301) Loud- Loud- Sound IF1 Pre- speaker speaker processing modulator Sound Sound IF2 Subwoofer Processing Headphone Headphone Sound Processing Prescale SCART1 SCART2 SCART SCART1 Input SCART3 Prescale SCART Select Output SCART4 Select MONO SCART2 Fig. 1–1: Simplified functional block diagram of the MSP 34x1G...
  • Page 28 28JW-74H MSP3411G (IC301) 4.6.1. Absolute Maximum Ratings Symbol Parameter Pin Name Min. Max. Unit − ° C Ambient Operating Temperature − − 40 ° C Storage Temperature − 0.3 First Supply Voltage AHVSUP SUP1 − 0.3 Second Supply Voltage DVSUP SUP2 −...
  • Page 29 28JW-74H VCT3834 (IC1001) VCT 38xxA/B Display RGBOUT Processor Video Panorama Video Comb Color Front-end Filter Decoder Scaler Back-end RGBIN Pict.Improv VOUT VSUPAB GNDAB AOUT MSync Audio Color, Prio VSync C Master 8-bit PWM 24 kB ROM 14-bit PWM 15:1 Mux...
  • Page 30 28JW-74H VCT3834 (IC1001) VSUPP3 GNDD GNDP3 VSUPD HOUT CLK20 TEST FBLIN VPROT SAFETY VBCLK HFLB 96 95 94 93 92 91 90 89 88 87 86 85 84 83 82 81 80 79 78 77 76 75 74 73 72 71 70 69 68 67 66 65...

  • Page 31: Pin Connection

    28JW-74H STV9380 (IC502) PIN CONNECTION CFLY + CFLY - BOOT EAout VREG FEEDCAP SGND FREQ PIN FUNCTIONS Name Function Number Negative supply Negative supply Negative supply PWM Output CFLY+ Flyback capacitor CFLY- Flyback capacitor BOOT Bootstrap capacitor VREG Internal voltage regulator...

  • Page 32: Electrical Characteristics

    28JW-74H STV9380 (IC502) +VCC 100nF 1000µF 100nF +VCC -VCC +VCC power STV9380 TDA9380 VREG CFLY+ Flyback -VCC Flyback CFLYBACK Vref detection generator 100µF 100nF CFLY- BOOT Cboot 220nF Output 1kΩ IN - Modulator drive Input signal Deflect. EA out 200Ω...

  • Page 33: Block Diagram

    28JW-74H TEA1507 (IC701) Block Diagram SUPPLY START-UP V CC DRAIN MANAGEMENT CURRENT SOURCE clamp internal UVLO start n.c. VALLEY supply M-level VOLTAGE CONTROLLED LOGIC OSCILLATOR 100 mV OVER- VOLTAGE FREQUENCY CONTROL PROTECTION OVER- LOGIC DRIVER DRIVER TEMPERATURE PROTECTION I ss −1...
  • Page 34 28JW-74H TEA1507 (IC701) CHARACTERISTICS = 25 °C; V = 15 V; all voltages are measured with respect to ground (pin 2); currents are positive when flowing into the IC; unless otherwise specified. SYMBOL PARAMETER CONDITIONS MIN. TYP. MAX. UNIT Start-up current source (pin 8) supply current drawn from drain pin = 0 V;...
  • Page 35 28JW-74H TEA1507 (IC701) SYMBOL PARAMETER CONDITIONS MIN. TYP. MAX. UNIT Burst mode standby (pin 3) burst mode standby active threshold at I = 6 mA th(burst)(on) burst voltage − − burst mode standby active current th(burst)(on) − − burst mode standby inactive current th(burst)(off) µs...

  • Page 36: Description Of Schematic Diagrams

    28JW-74H DESCRIPTION OF SCHEMATIC DIAGRAMS NOTE: SAFETY NOTE: 1. The unit of resistance « ohm »is omitted (K=1000 1. DISCONNECT THE AC PLUG FROM THE AC ohms. M= Megaohm). OUTLET BEFORE REPLACING PARTS. 2. All resistors are 1/8 watt. unless otherwise noted.
  • Page 37 28JW-74H Pin4 Vp-p= 80V Pin5 Vp-p= 90V Pin6 Vp-p= 80V Pin7 Vp-p= 0.8V Pin8 Vp-p= 225V Pin9 Vp-p=1200V Pin10 Vp-p= 0.5V Pin11 Vp-p= 1.8V Pin12 Vp-p= 0.5V Pin14 Vp-p= 58V Pin13 Vp-p=5.6V Pin15 Vp-p= 0.9V...
  • Page 38 28JW-74H Pin16 Vp-p= 9.2V Pin17 Vp-p= 0.24V Pin18 Vp-p= 9.6V Pin19 Vp-p= 0.2V Pin20 Vp-p= 9.2V Pin21 Vp-p= 1.4V Pin22 Vp-p= 1.4V Pin23 Vp-p= 0.7V Pin24 Vp-p= 500V...
  • Page 39 28JW-74H SCHEMATIC DIAGRAM OF CRT UNIT (FB218N2)
  • Page 40 28JW-74H SCHEMATIC DIAGRAM OF MAIN 1 (FB217N2)
  • Page 41 28JW-74H SCHEMATIC DIAGRAM OF MAIN 1 (FB217N2)
  • Page 42 28JW-74H SCHEMATIC DIAGRAM OF MAIN 2 (FB217N2)
  • Page 43 28JW-74H SCHEMATIC DIAGRAM OF MAIN 2 (FB217N2)
  • Page 44 28JW-74H SCHEMATIC DIAGRAM OF MAIN 3 (FB217N2)
  • Page 45 28JW-74H SCHEMATIC DIAGRAM OF MAIN 3 (FB217N2)
  • Page 46 28JW-74H SCHEMATIC DIAGRAM OF MAIN 4 (FB217N2)
  • Page 47 28JW-74H SCHEMATIC DIAGRAM OF MAIN 4 (FB217N2)
  • Page 48 28JW-74H SCHEMATIC DIAGRAM OF CONTROL UNIT (FB219N1)

  • Page 49: Troubleshooting Tables

    28JW-74H TROUBLESHOOTING TABLES 12 3,&785(...
  • Page 50 28JW-74H...
  • Page 51 28JW-74H 12 6281' 12 9(57,&$/ 6&$1...

  • Page 52: Parts Listing

    28JW-74H PARTS LISTING REF No. PARTS DESCRIPTION * CODE REPLACEMENT PARTS Replacement parts which have special safety characteristics are identified in this manual. Electrical components having such features are identified by in the Replacement Parts Listing. The use of a substitute replacement part which does not have the same safety characteristics as the factory recommended is not permitted.
  • Page 53 28JW-74H REF No. PARTS DESCRIPTION * CODE REF No. PARTS DESCRIPTION * CODE CERAMIC FILTERS TRANSFORMERS CAPACITORS PACKAGED CIRCUITS COILS...
  • Page 54 28JW-74H REF No. PARTS DESCRIPTION * CODE REF No. PARTS DESCRIPTION * CODE...
  • Page 55 28JW-74H REF No. PARTS DESCRIPTION * CODE REF No. PARTS DESCRIPTION * CODE RESISTORS...
  • Page 56 28JW-74H REF No. PARTS DESCRIPTION * CODE REF No. PARTS DESCRIPTION * CODE...
  • Page 57 28JW-74H REF No. PARTS DESCRIPTION * CODE REF No. PARTS DESCRIPTION * CODE MISCELLANEOUS PARTS...
  • Page 58 28JW-74H REF No. PARTS DESCRIPTION * CODE REF No. PARTS DESCRIPTION * CODE PWB-B CRT UNIT INTEGRATED CIRCUITS TRANSISTORS DIODES MISCELLANEOUS PARTS CAPACITORS PWB-C CONTROL UNIT INTEGRATED CIRCUITS TRANSISTORS RESISTORS DIODES...
  • Page 59 28JW-74H REF No. PARTS DESCRIPTION * CODE REF No. PARTS DESCRIPTION * CODE CAPACITORS MISCELLANEOUS PARTS RESISTORS CABINET PARTS COILS MISCELLANEOUS PARTS...

  • Page 60: Source Of Documentation

    28JW-74H SOURCE OF DOCUMENTATION 1. TDA 9885, Philips Data Sheet: TDA9885; TDA9886. I C-bus controlled single/multistandard alignment-fee IF-PLL. Product specification. 2002 Mar 05. http://www.semiconductors.philips.com/acrobat/datasheets/TDA9885_TDA9886_1.pdf 2. TDA 7480, ST Microelectronics Data Sheet: TDA7480. 10W Mono Class D Amplifier. September 1998 http://us.st.com/stonline/books/pdf/docs/4839.pdf 3.

  • Page 61: Packing Of The Set & Accessories

    28JW-74H PACKING OF THE SET & ACCESSORIES Pack-ad SPAKX4077BMZZ Wrapper SPAKP2006BMZZ FRONT SPAKC5495BMZZ Carton Box Batteries UBATU0013TAZZ Remote Control RRMCG1073BMSA Operation Manual Set FRONT Carton Box...
  • Page 62 28JW-74H Notes:...
  • Page 63 28JW-74H Notes:...
  • Page 64 SHARP ELECTRONICA ESPAÑA S.A. PRINTED BY: TV Division Think Ecology, please use Engineering Dept.

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