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.
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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.
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.
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.
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.
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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.
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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.
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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.
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.
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.
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) −...
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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 −...
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28JW-74H TDA9885 (IC201) BLOCK DIAGRAM handbook, full pagewidth...
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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...
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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"...
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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.
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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 −...
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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...
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...
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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;...
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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...
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.
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.
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.
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...