Symphonic WFT20M4 Service Manual
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Symphonic WFT20M4 Service Manual

Symphonic WFT20M4 Service Manual

20" color television
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SERVICE MANUAL

20" COLOR TELEVISION
WFT20M4

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Summary of Contents for Symphonic WFT20M4

  • Page 1: Service Manual

    SERVICE MANUAL 20" COLOR TELEVISION WFT20M4...

  • Page 2: Table Of Contents

    IMPORTANT SAFETY NOTICE Proper service and repair is important to the safe, reliable operation of all Funai Equipment. The service procedures recommended by Funai and de- scribed in this service manual are effective methods of performing service operations. Some of these service special tools should be used when and as recommended.

  • Page 3: Specifications

    SPECIFICATIONS <TUNER> ANT. Input ------------------- 75ohm Unbal., F type Reference Level ----------- 20Vp-p (CRT Green Cathode) Test Input Signal ---------- 400Hz 30% modulation Description Condition Unit Nominal Limit 1. Intermediate Freq. Picture 45.75 Sound 41.25 2. Peak Picture Sens dBµv CATV dBµv dBµv...

  • Page 4: Important Safety Precautions

    IMPORTANT SAFETY PRECAUTIONS Prior to shipment from the factory, our products are strictly inspected for recognized product safety and electrical codes of the countries in which they are to be sold. However, in order to maintain such compliance, it is equally important to implement the following precautions when a set is being serviced.
  • Page 5 ing is performed that involves B+, horizontal de- earth ground. If a voltage reading in excess of 1.0V flection or high voltage. Correct operation of the X- is obtained, remove and reinsert the AC power radiation protection circuits also must be recon- plug in the opposite polarity and again measure firmed each time they are serviced.
  • Page 6 Precautions during Servicing 3) Align the lengths of the wires to be connected. In- sert the wires fully into the connector. A. Parts identified by the ( # ) symbol are critical for 4) Use the crimping tool to crimp the metal sleeve at safety.
  • Page 7 Safety Check after Servicing Examine the area surrounding the repaired location Chassis or Secondary Conductor for damage or deterioration. Observe that screws, parts and wires have been returned to original posi- tions. Afterwards, perform the following tests and con- Primary Circuit Terminals firm the specified values in order to verify compliance with safety standards.

  • Page 8: Standard Notes For Servicing

    STANDARD NOTES FOR SERVICING Circuit Board Indications How to Remove / Install Flat Pack-IC a. The output pin of the 3 pin Regulator ICs is indicat- 1. Removal ed as shown. With Hot-Air Flat Pack-IC Desoldering Machine: (1) Prepare the hot-air flat pack-IC desoldering ma- Top View Bottom View chine, then apply hot air to the Flat Pack-IC (about...
  • Page 9 3. The flat pack-IC on the CBA is affixed with glue, so With Soldering Iron: be careful not to break or damage the foil of each (1) Using desoldering braid, remove the solder from pin or the solder lands under the IC when remov- all pins of the flat pack-IC.
  • Page 10 2. Installation (4) Bottom of the flat pack-IC is fixed with glue to the CBA; when removing entire flat pack-IC, first apply (1) Using desoldering braid, remove the solder from soldering iron to center of the flat pack-IC and heat the foil of each pin of the flat pack-IC on the CBA up.
  • Page 11 Instructions for Handling Semiconductors Electrostatic breakdown of the semiconductors may occur due to a potential difference caused by electro- static charge during unpacking or repair work. 1. Ground for Human Body Be sure to wear a grounding band (1MΩ) that is prop- erly grounded to remove any static electricity that may be charged on the body.

  • Page 12: Cabinet Disassembly Instructions

    CABINET DISASSEMBLY INSTRUCTIONS 1. Disassembly Flowchart Note : (1) Order of steps in procedure. When reassembling, This flowchart indicates the disassembly steps for the follow the steps in reverse order. These numbers cabinet parts, and the CBA in order to gain access to are also used as the Identification (location) No.
  • Page 13 (S-1) (S-1) (S-1) [3] Main CBA (S-1) (S-3) [1] Rear Cabinet Fig. 1 Fig. 3 [2] CRT CBA (S-1) Anode Cap (S-2) (S-1) (S-2) (S-3) (S-2) (S-1) (S-1) (S-1) (S-2) [1] Rear Cabinet [4] CRT Fig. 2 Fig. 4 L2403DC...
  • Page 14 TV Cable Wiring Diagram DG691 DEGAUSSING COIL SP801 MAIN CBA CLN801 CN801 CN691 WH301A TU11 FLYBACK TUNER TRANSFORMER CN571 T571 WH501A TO CRT GROUND AC601 WH501B AC CORD CN1501 FOCUS JK1501 SCREEN WH301B ANODE Fig. 5 L2403DC...

  • Page 15: Electrical Adjustment Instructions

    ELECTRICAL ADJUSTMENT INSTRUCTIONS How to set up the service mode: General Note: "CBA" is abbreviation for "Circuit Board Assem- Service mode: bly." 1. Use the service remote control unit. NOTE: 2. Turn the power on. (Use main power on the TV Electrical adjustments are required after replacing unit.) circuit components and certain mechanical parts.

  • Page 16: Initial Setting

    2. Initial Setting 3. Setting for BRIGHT, CONTRAST, COLOR, TINT, and SHARPNESS General Data Values 1. Enter the Service mode. (See page 5-1) 2. Press "VOL p" button on the service remote control General unit. Display changes "C/D," "7F," "LANGUAGE," 1.
  • Page 17 4. H f Adjustment 6. Purity Check 1. Enter the Service mode. (See page 5-1) Purpose: To get correct horizontal frequency. 2. Press "7" button on the remote control unit. Each Use service remote control unit. time pressing 7" button on the remote control unit, 1.
  • Page 18 8. H. Position Adjustment 10. V. Position Adjustment Purpose: To obtain correct horizontal position of Purpose: To obtain correct vertical width of screen image. screen image. Symptom of misadjustment: If V. Position is incor- Symptom of Misadjustment: If H. Position is incor- rect, vertical height of image on the screen may not be rect, horizontal position of image on the screen may properly displayed.
  • Page 19 12. Cut-off Adjustment 13. White Balance Adjustment Purpose: To adjust the beam current of R, G, B, and Purpose: To mix red, green and blue beams correctly screen voltage. for pure white. Symptom of Misadjustment: White color may be Symptom of Misadjustment: White becomes bluish reddish, greenish or bluish.

  • Page 20: Purity Adjustment

    14. Sub-Brightness Adjustment The following adjustments normally are not attempted in the field. Only when replacing the Purpose: To get proper brightness. CRT then adjust as a preparation. Symptom of Misadjustment: If Sub-Brightness is 16. Purity Adjustment incorrect, proper brightness cannot be obtained by adjusting the Brightness Control.

  • Page 21: Convergence Adjustment

    17. Convergence Adjustment Purpose: To obtain proper convergence of red, green and blue beams. Symptom of Misadjustment: If Convergence Adjust- ment is incorrect, the edge of white letters may have color edges. Test Point Adj. Point Mode Input C.P. Magnet Dot Pattern (RB), C.P .

  • Page 22: Block Diagrams

    BLOCK DIAGRAMS IF/Video/System Control Block Diagram L2403BLIF...
  • Page 23 Audio/Power Control Block Diagram L2403BLA...
  • Page 24 CRT/H.V. Block Diagram L2403BLCRT...
  • Page 25 Power Supply Block Diagram L2403BLP...

  • Page 26: Schematic Diagrams / Cba's And Test Points

    SCHEMATIC DIAGRAMS / CBA'S AND TEST POINTS Standard Notes Many electrical and mechanical parts in this chassis have special characteristics. These characteristics often pass unnoticed and the protection afforded by them cannot necessarily be obtained by using replacement compo- nents rated for higher voltage, wattage, etc. Replacement parts that have these special safety characteristics are identified in this manual and its supplements;...
  • Page 27 LIST OF CAUTION, NOTES, AND SYMBOLS USED IN THE SCHEMATIC DIAGRAMS ON THE FOLLOWING PAGES: 1. CAUTION: FOR CONTINUED PROTECTION AGAINST RISK OF FIRE, REPLACE ONLY WITH SAME TYPE_A,_V FUSE. ATTENTION: UTILISER UN FUSIBLE DE RECHANGE DE MÊME TYPE DE_A,_V. 2.
  • Page 28 Main 1/3 Schematic Diagram VIDEO SIGNAL MAIN 1/3 Ref No. Position IC111 IC151 IC801A TRANSISTORS Q111 Q321 CONNECTOR CN801 L2403SCM1...
  • Page 29 Main 2/3 Schematic Diagram CAUTION ! IF SIGNAL Fixed voltage ( or Auto voltage selectable ) power supply circuit is used in this unit. CAUTION: FOR CONTINUED PROTECTION AGAINST RISK NOTE : VIDEO SIGNAL If Main Fuse (F601) is blown, check to see that all components in the power supply OF FIRE, REPLACE ONLY WITH SAME TYPE 4A, 125V FUSE.
  • Page 30 Main 3/3 & CRT Schematic Diagram MAIN 3/3 Ref No. Position Ref No. Position Ref No. Position TRANSISTORS CONNECTORS Q1511 WH501A IC551 Q1521 TRANSISTORS WH301A Q1531 TEST POINTS Q571 CONNECTORS Q572 TP591 CN1501 CONNECTORS TP592 WH301B CN571 TP601 WH501B VIDEO SIGNAL L2403SCM3...
  • Page 31 Main CBA Top View CAUTION ! CAUTION: FOR CONTINUED PROTECTION AGAINST RISK BECAUSE A HOT CHASSIS GROUND IS PRESENT IN THE POWER Fixed voltage ( or Auto voltage selectable ) power supply circuit is used in this unit. OF FIRE, REPLACE ONLY WITH SAME TYPE 4A, 125V FUSE. SUPPLY CIRCUIT, AN ISOLATION TRANSFORMER MUST BE USED.
  • Page 32 Main CBA Bottom View CAUTION: FOR CONTINUED PROTECTION AGAINST RISK BECAUSE A HOT CHASSIS GROUND IS PRESENT IN THE POWER CAUTION ! OF FIRE, REPLACE ONLY WITH SAME TYPE 4A, 125V FUSE. Fixed voltage ( or Auto voltage selectable ) power supply circuit is used in this unit. SUPPLY CIRCUIT, AN ISOLATION TRANSFORMER MUST BE USED.
  • Page 33 CRT CBA Top View CRT CBA Bottom View CRT CBA Ref No. Position TRANSISTORS Q1511 Q1521 Q1531 CONNECTORS CN1501 WH301B WH501B WF14 WF15 Q1521 Q1521 Q1511 Q1511 Collector Base Collector Base Q1531 Base WF13 Q1531 Collector 7-13 7-14 BL2700F01012-2...

  • Page 34: Waveforms

    WAVEFORMS WF1 ~ WF16 = Waveforms to be observed at Waveform check points. (Shown in Schematic Diagram.) Input: NTSC Color Bar Signal (with 1kHz Audio Signal) INITIAL POSITION: Unplug unit from AC outlet for at least 5 minutes. reconnect to AC outlet and then turn power on. (Brightness---Center Color---Center Tint --- Center Contrast---Approx 70%) 1DIV: 2V 20µs 1DIV: 0.5V 20µs...
  • Page 35 WF1 ~ WF16 = Waveforms to be observed at Waveform check points. (Shown in Schematic Diagram.) Input: NTSC Color Bar Signal (with 1kHz Audio Signal) INITIAL POSITION: Unplug unit from AC outlet for at least 5 minutes. reconnect to AC outlet and then turn power on. (Brightness---Center Color---Center Tint --- Center Contrast---Approx 70%) 1DIV: 200V 20µs WF13...

  • Page 36: Wiring Diagram

    WIRING DIAGRAM CN801 CLN801 1 SPEAKER SP801 SP-GND SPEAKER ANODE TU11 TUNER UNIT V501 MAIN CBA BL2700F01012-1 CN691 FOCUS CN1501 T571 SCREEN WH301B WH301A CLN301 BLUE BLUE GREEN GREEN WH501B WH501A CLN501 CRT CBA HEATER 3 HEATER BL2700F01012-2 GND 2 +200V 1 +200V DY551...

  • Page 37: Ic Pin Functions

    IC PIN FUNCTIONS IC111 (TV Micro Controller) Signal Name Function Signal Name Function 35 N.U. Not Used 36 N.U. Not Used CNVSS 37 V RAMP F/B V Ramp Feed Back N.U. Not Used 38 V RAMP OUT Vertical Output N.U. Not Used 39 V RAMP CAP V Ramp OSC Capacitor...
  • Page 38 Signal Name Function 71 N.U. Not Used White Balance Adjustment 72 I2C OPEN Judgement 73 AFT-IN AFT Voltage Input 74 DG-ON-H Degaussing Coil Control 75 AGC AGC Voltage Input 76 PROTECT-3 Power Supply Protection 77 N.U. Not Used 78 N.U. Not Used 79 P-ON-H Output for P-ON-H...

  • Page 39: Exploded Views

    EXPLODED VIEWS Cabinet SHINWHA TAPE SGT-730 V501-1 (BLACK) V501-2 Details for DY551 and surrounding parts SHINWHA TAPE SGT-730 DY551 (WHITE) Scotch Tape #880 B-11 CLN801 CLN551 DY551 L-13 CRT CBA B-11 SP801 B-13 DG691 Scotch Tape #880 V501 AC601 MAIN CBA 11-1 11-2 L2403CEX...
  • Page 40 Packing Tape Packing Tape 11-3 L2403PEX...

  • Page 41: Mechanical Parts List

    MECHANICAL PARTS LIST PRODUCT SAFETY NOTE: Products marked with a # have special characteristics important to safety. Before replacing any of these components, read carefully the product safety notice in this service manual. Don't degrade the safety of the product through improper ser- vicing.

  • Page 42: Electrical Parts List

    ELECTRICAL PARTS LIST PRODUCT SAFETY NOTE: Products marked with a Ref. No. Description Part No. # have special characteristics important to safety. FILM CAP .(P) 0.047µF/50V J or CMA1JJS00473 Before replacing any of these components, read care- FILM CAP .(P) 0.047µF/50V J CA1J473MS029 fully the product safety notice in this service manual.
  • Page 43 Ref. No. Description Part No. Ref. No. Description Part No. ELECTROLYTIC CAP . 1µF/50V M or CE1JMASDL010 C609 CERAMIC CAP . LB 680pF/2K or CA3D681KG004 ELECTROLYTIC CAP . 1µF/50V M CE1JMASTL010 CERAMIC CAP . BN 680pF/2KV or CCD3DKA0B681 C343 CHIP CERAMIC CAP . B K 0.01µF/50V CHD1JKB0B103 CERAMIC CAP .
  • Page 44 Ref. No. Description Part No. Ref. No. Description Part No. ELECTROLYTIC CAP . 47µF/16V M CE1CMASDL470 D611 ZENER DIODE MTZJT-7715B or QDTB00MTZJ15 CONNECTORS ZENER DIODE DZ-15BSBT265 NDTB00DZ15BS D612 ZENER DIODE MTZJT-7718B or QDTB00MTZJ18 CN571 CONNECTOR BASE, 5P TV-50P-05-V3 or J3TVC05TG002 ZENER DIODE DZ-18BSBT265 NDTB00DZ18BS CONNECTOR BASE, 5P RTB-1.5-5P or...
  • Page 45 Ref. No. Description Part No. Ref. No. Description Part No. PHOTO COUPLER PS2501-1L or QPEL0PS25011 TRANSISTOR KTA1266(GR) or NQS40KTA1266 PHOTOCOUPLER LTV-817B-F or NPEB0LTV817F TRANSISTOR 2SA1318(T)-AANP or 2SA1318TZ PHOTOCOUPLER LTV-817C-F NPEC0LTV817F TRANSISTOR 2SA1318(U)-AANP or 2SA1318UZ IC801A AUDIO AMP IC AN17811A QSZAA0SMS015 TRANSISTOR 2SA1015-GR(TPE2) QQS102SA1015 COILS...
  • Page 46 Ref. No. Description Part No. Ref. No. Description Part No. CHIP RES.(1608) 1/10W J 2.2k Ω CARBON RES. 1/4W J 15 Ω R135 RRXAJB5Z0222 R579 RCX4JATZ0150 CHIP RES.(1608) 1/10W J 100k Ω R136 RRXAJB5Z0104 R581 PCB JUMPER D0.6-P5.0 JW5.0T CHIP RES.(1608) 1/10W J 100 Ω METAL OXIDE FILM RES.
  • Page 47 Ref. No. Description Part No. Ref. No. Description Part No. CHIP RES.(1608) 1/10W J 10k Ω R680 RRXAJB5Z0103 BC603 BEAD INDUCTORS FBR07HA121TB-00 LLBF00ZTU021 CARBON RES. 1/4W J 12 Ω R681 RCX4JATZ0120 BC652 BEAD INDUCTORS FBR07HA121TB-00 LLBF00ZTU021 METAL RESISTOR 2W J 39 Ω or R682 RN02390ZU001 BC653...
  • Page 48 Ref. No. Description Part No. Ref. No. Description Part No. CARBON RES. 1/4W J 560 Ω TP300 PCB JUMPER D0.6-P12.5 JW12.5T R1528 RCX4JATZ0561 CHIP RES.(1608) 1/10W J 33 Ω TP591 PCB JUMPER D0.6-P5.0 JW5.0T R1529 RRXAJB5Z0330 METAL OXIDE FILM RES. 1W J 15k Ω or TP592 PCB JUMPER D0.6-P5.0 JW5.0T...
  • Page 49 WFT20M4 L2403UD 2004-05-06...

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