Emerson EWFG2705 Service Manual
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Emerson EWFG2705 Service Manual

Emerson EWFG2705 Service Manual

27" analog/digital color television
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SERVICE MANUAL
27" ANALOG/DIGITAL
COLOR TELEVISION
EWFG2705

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Summary of Contents for Emerson EWFG2705

  • Page 1 SERVICE MANUAL 27″ ANALOG/DIGITAL COLOR TELEVISION EWFG2705...

  • 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 described 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 Test input Video Input: 1V p-p Audio input: 500mV rms Tuner: Ant input (80dBuV) Video 87.5% < DEFLECTION > Description Condition Unit Limit Horizontal 90±5 1. Over Scan Vertical 90±5 Horizontal ±15 2. Linearity Vertical ±10 3. High Voltage 25 to 33 <...
  • Page 4 Description Condition Unit Limit <6 <6 <6 <6 5. MULTIPATH <6 <6 <6 <6 >50 6. Audio S/N (0dBfs) >50 <3 7. Audio DIST. (0dBfs) <3 Note: Nominal specifications represent the design specifications. All units should be able to approximate these. Some will exceed and some may drop slightly below these specifications.

  • Page 5: 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 6 Also, because the picture tube shields and an isolation transformer only if the AC power mounting hardware perform an X-radiation plug is inserted so that the chassis is protection function, they must be correctly in connected to the ground side of the AC power place.
  • Page 7 of the countries in which they are to be sold. 3) Align the lengths of the wires to be connected. However, in order to maintain such compliance, it Insert the wires fully into the connector. is equally important to implement the following 4) Use the crimping tool to crimp the metal sleeve precautions when a set is being serviced.
  • Page 8 Safety Check after Servicing Examine the area surrounding the repaired location for damage or deterioration. Observe that screws, parts and wires have been returned to original positions. Afterwards, perform the following tests and confirm the specified values in order to verify compliance with safety standards. 1.

  • Page 9: Standard Notes For Servicing

    STANDARD NOTES FOR SERVICING Circuit Board Indications How to Remove / Install Flat Pack-IC 1. The output pin of the 3 pin Regulator ICs is 1. Removal indicated as shown. With Hot-Air Flat Pack-IC Desoldering Machine: Top View Bottom View 1.
  • Page 10 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 all pins of the flat pack-IC.
  • Page 11 2. Installation With Iron Wire: 1. Using desoldering braid, remove the solder from 1. Using desoldering braid, remove the solder from all pins of the flat pack-IC. When you use solder the foil of each pin of the flat pack-IC on the CBA flux which is applied to all pins of the flat pack-IC, so you can install a replacement flat pack-IC more you can remove it easily.
  • Page 12 Instructions for Handling Semi- conductors Electrostatic breakdown of the semi-conductors may occur due to a potential difference caused by electrostatic charge during unpacking or repair work. 1. Ground for Human Body Be sure to wear a grounding band (1 MΩ) that is properly grounded to remove any static electricity that may be charged on the body.

  • Page 13: 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 14 [4] Digital CBA [3] Main CBA Front Cabinet Control Plate [1] Rear Cabinet Fig. D1 Fig. D3 Degaussing Coil Anode Cap [1] Rear Cabinet [2] CRT Ground Wire Front Cabinet [5] CRT Front Cabinet Control Plate Control Plate Fig. D2 Fig.
  • Page 15 TV Cable Wiring Diagram DG691 SP802 SP801 DEGAUSSING COIL MAIN CBA VIDEO-2 CLN801 CLN802 FRONT JACKS CN802 CN801 CN691 WH301A DIGITAL CBA TU11 TUNER T571 FLYBACK TRANSFORMER CN902 CN571 WH501A CN901 TO CRT GROUND FOCUS JK1501 AC601 AC CORD CN1501 WH501B SCREEN WH301B...

  • Page 16: Electrical Adjustment Instructions

    ELECTRICAL ADJUSTMENT INSTRUCTIONS General Note: “CBA” is abbreviation for How to enter the service mode: “Circuit Board Assembly.” Service mode: Note: Electrical adjustments are required after 1. Use the service remote control unit. replacing circuit components and certain 2. Turn the power on. (Use main power on the TV mechanical parts.
  • Page 17 2. Initial Setting C-CLR 1. Press [MENU] button on the service remote General control unit. Then select “COMPONENT COLOR” 1. Enter the Service mode. (See page 5-1.) (C-CLR) display. 2. Press [VOL p] button on the service remote 2. Press [CH o / p] buttons on the service remote control unit.
  • Page 18 4. H f Adjustment 6. SD Check Mode 1. Enter the Service mode. (See page 5-1.) Purpose: To get correct horizontal frequency. 2. Press [1] button on the remote control unit. The Note: Use service remote control unit. unit enter the SD-Check mode. 1.
  • Page 19 7. H. Position Adjustment 9. V. Position Adjustment Purpose: To obtain correct vertical width of screen Purpose: To obtain correct horizontal position of image. screen image. Symptom of misadjustment: If V. Position is Symptom of Misadjustment: If H. Position is incorrect, vertical height of image on the screen may incorrect, horizontal position of image on the screen not be properly displayed.
  • Page 20 11. Cut-off Adjustment with steps 4, 5 and 6 the horizontal line should be pure white if not, then attempt the Cut off Purpose: To adjust the beam current of R, G, B, and adjustment again. screen voltage. 12. White Balance Adjustment Symptom of Misadjustment: White color may be reddish, greenish or bluish.
  • Page 21 9. At this time, Re-check that Horizontal line is white. 4. Press [VOL o / p] button on the service remote If not, Re-adjust Cut-off Adjustment until the control unit and select “U-Offset YUV (Magenta)” Horizontal Line becomes pure white. mode.
  • Page 22 17. Sub-Brightness Adjustment 18. Focus Adjustment Purpose: To get proper brightness. Purpose: Set the optimum Focus. Symptom of Misadjustment: If Sub-Brightness is Symptom of Misadjustment: If Focus Adjustment is incorrect, proper brightness cannot be obtained by incorrect, blurred images are shown on the display. adjusting the Brightness Control.
  • Page 23 19. Purity Adjustment 21. Convergence Adjustment Purpose: To obtain pure color. Purpose: To obtain proper convergence of red, green and blue beams. Symptom of Misadjustment: If Color Purity Adjustment is incorrect, large areas of color may not Symptom of Misadjustment: If Convergence be properly displayed.
  • Page 24 4. Remove the DY Wedges and slightly tilt the Deflection Yoke horizontally and vertically to obtain the best overall convergence. 5. Fix the Deflection Yoke by carefully inserting the DY Wedges between CRT and Deflection Yoke. 22. Yh, Yv, Xv Adjustment 1.

  • Page 25: How To Initialize The Analog/Digital Color Television

    HOW TO INITIALIZE THE ANALOG/DIGITAL COLOR TELEVISION To put the program back at the factory-default, initialize the Analog/Digital Color Television as the following procedure. 1. Use the service remote control unit. 2. Turn the power on. (Use main power on the TV unit.) 3.

  • Page 26: Block Diagrams

    BLOCK DIAGRAMS System Control Block Diagram L3821BLS...
  • Page 27 DTV Block Diagram L3821BLD...
  • Page 28 IF/Video Block Diagram L3821BLIF...
  • Page 29 Audio Block Diagram L3821BLA...
  • Page 30 CRT/H.V. Block Diagram L3821BLCRT...
  • Page 31 Power Supply Block Diagram L3821BLP...

  • Page 32: 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 components rated for higher voltage, wattage, etc. Replacement parts that have these special safety characteristics are identified in this manual and its supplements;...
  • Page 33 LIST OF CAUTION, NOTES, AND SYMBOLS USED IN THE SCHEMATIC DIAGRAMS ON THE FOLLOWING PAGES: 1. CAUTION: 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 34 Main 1/5 Schematic Diagram MAIN 1/5 Ref No. Position IC301 IC381 IC421 TRANSISTORS Q321 Q322 Q381 Q382 Q383 CONNECTORS CN301 CN302 L3821SCM1...
  • Page 35 Main 2/5 Schematic Diagram MAIN 2/5 Ref No. Position IC451 IC701 IC801 TRANSISTORS Q351 Q352 Q811 CONNECTORS CN801 CN802 L3821SCM2...
  • Page 36 Main 3/5 Schematic Diagram MAIN 3/5 Ref No. Position IC31 IC901 IC903 IC904 IC910 IC911 TRANSISTORS Q901 Q902 Q910 CONNECTORS CN901 CN902 L3821SCM3...
  • Page 37 Main 4/5 & CRT Schematic Diagram MAIN 4/5 Ref No. Position IC551 TRANSISTORS Ref No. Position Q552 TRANSISTORS Q571 Q1511 Q572 Q1512 CONNECTORS Q1521 CN571 Q1522 WH301A Q1531 WH501A Q1532 TEST POINTS CONNECTORS TP300 CN1501 TP591 WH301B TP592 WH501B TP601 L3821SCM4...
  • Page 38 Main 5/5 Schematic Diagram CAUTION ! NOTE: CAUTION ! : For continued protection against risk of fire, Fixed voltage (or Auto voltage selectable) power supply circuit is used in this unit. The voltage for parts in hot circuit is measured using replace only with same type 4 A, 125V fuse.
  • Page 39 Digital 1/3 Schematic Diagram 1 NOTE: 1. The order of pins shown in this diagram is different from that of actual IC101. 2. IC101 is divided into two and shown as IC101 (1/2) ~ IC101 (2/2) in this Digital Schematic Diagram Section. DIGITAL 1/3 Ref No.
  • Page 40 Digital 2/3 Schematic Diagram DIGITAL 2/3 Ref No. Position IC253 TRANSISTOR Q281 L3821SCD2...
  • Page 41 Digital 3/3 Schematic Diagram 1 NOTE: 1. The order of pins shown in this diagram is different from that of actual IC101. 2. IC101 is divided into two and shown as IC101 (1/2) ~ IC101 (2/2) in this Digital Schematic Diagram Section. DIGITAL 3/3 Ref No.
  • Page 42 Main CBA Top View CAUTION ! MAIN CBA CAUTION ! : For continued protection against risk of fire, Fixed voltage (or Auto voltage selectable) power supply circuit is used in this unit. Ref No. Position replace only with same type 4 A, 125V fuse. If Main Fuse (F601) is blown , check to see that all components in the power supply 4A/125V ATTENTION : Utiliser un fusible de rechange de même type de 4A, 125V.
  • Page 43 Main CBA Bottom View CAUTION ! Because a hot chassis ground is present in the power Fixed voltage (or Auto voltage selectable) power supply circuit is used in this unit. CAUTION ! : For continued protection against risk of fire, supply circuit, an isolation transformer must be used.
  • Page 44 CRT CBA Top View CRT CBA Bottom View CRT CBA Ref No. Position TRANSISTORS Q1511 Q1512 Q1521 Q1522 Q1531 Q1532 CONNECTORS CN1501 WH301B WH501B Q1522 Q1532 Q1512 Collector Collector Collector 8-13 BL3820F01012-2...

  • Page 45: Waveforms

    WAVEFORMS WF1 ~ WF21 = Waveforms to be observed at Waveform check points. (Shown in Schematic Diagram.) Input: 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: 50V 20µs 1DIV: 10V 5ms...
  • Page 46 WF1 ~ WF21 = Waveforms to be observed at Waveform check points. (Shown in Schematic Diagram.) Input: 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%) WF13 1DIV: 1V 500ns...

  • Page 47: Wiring Diagram

    WIRING DIAGRAM L3821WI 10-1...

  • Page 48: Ic Pin Function Descriptions

    IC PIN FUNCTION DESCRIPTIONS IC301 (TV Micro Controller) Signal Name Function Signal Name Function 41 Cr2-IN[YUV] Cr2-IN[YUV] 42 Y2-IN[YUV] Y2-IN[YUV] RCV-IN Input For Remote Control 43 NU Not used VOLUME Volume PWM 44 VCC(+9V) VREGVCC DTV-H DTV-on-H 45 CVBS3-IN Composite Signal 3 Input P-ON-H Output for P-ON-H 46 NU...

  • Page 49: Exploded Views

    EXPLODED VIEWS Cabinet SHINWHA V501-1 TAPE SGT-730 Details for DY551 (BLACK) and surrounding parts V501-2 SHINWHA L-10 TAPE SGT-730 (WHITE) DY551 B-11 B-20 Scotch Tape #880 CLN551 SP801 V501 L-13 DY551 CRT CBA B-11 DG691 CLN801 B-20 B-20 Scotch Tape #880 SP802 L-13 B-20...
  • Page 50 Packing Tape Packing tape 12-2 L3821PEX...

  • Page 51: Mechanical Parts List

    Description Part No. FRONT CABINET L3821UB 1EM120587 REAR CABINET L3820UA 1EM120255 CONTROL PLATE L3821UB 1EM320740 A-4# RATING LABEL L3821UB ---------- BRAND BADGE L1444UQ~EMERSON~ 0EM407707 SPRING TENSION B0080B0 EM40808 26WH006 SCREW L1500UA 0EM406142 B-11 CLOTH 190X15XT0.5 TS7623 B-12 CLOTH L1440JL 15X55XT1.0...

  • Page 52: Electrical Parts List

    ELECTRICAL PARTS LIST PRODUCT SAFETY NOTE: Products marked with a Ref. No. Description Part No. # have special characteristics important to safety. CHIP CERAMIC CAP .(1608) B K 0.01µF/ 50V CHD1JK30B103 Before replacing any of these components, read C301 ELECTROLYTIC CAP . 10µF/ 50V M CE1JMASDL100 carefully the product safety notice in this service C303...
  • Page 53 Ref. No. Description Part No. Ref. No. Description Part No. C456 CHIP CERAMIC CAP .(1608) F Z 0.1µF/ 50V CHD1JZ30F104 C667 ELECTROLYTIC CAP . 1µF/ 50V M CE1JMASDL1R0 C457 CHIP CERAMIC CAP .(1608) B K 0.033µF/ 50V CHD1JK30B333 C674 ELECTROLYTIC CAP . 1µF/ 50V M CE1JMASDL1R0 C458 ELECTROLYTIC CAP .
  • Page 54 Ref. No. Description Part No. Ref. No. Description Part No. D392 SWITCHING DIODE 1SS133(T-77) QDTZ001SS133 IC601# PHOTO COUPLER PS2501-1L QPEL0PS25011 D393 SWITCHING DIODE 1SS133(T-77) QDTZ001SS133 IC701 IC SWITCHING TC4052BF(EL) QSZBA0TTS096 D501 SCHOTTKY BARRIER DIODE SB140 NDQZ000SB140 IC801 IC AN17812A QSZBA0SMS017 D502# ZENER DIODE MTZJT-7720B QDTB00MTZJ20...
  • Page 55 Ref. No. Description Part No. Ref. No. Description Part No. CHIP RES.(1608) 1/10W J 2.2k Ω CHIP RES.(1608) 1/10W J 22k Ω RRXAJR5Z0222 R373 RRXAJR5Z0223 CHIP RES.(1608) 1/10W J 270k Ω CHIP RES.(1608) 1/10W J 100 Ω RRXAJR5Z0274 R374 RRXAJR5Z0101 CHIP RES.(1608) 1/10W 0 Ω...
  • Page 56 Ref. No. Description Part No. Ref. No. Description Part No. CARBON RES. 1/4W J 27 Ω CHIP RES.(1608) 1/10W J 56k Ω R579# RCX4JATZ0270 R678# RRXAJR5Z0563 CHIP RES.(1608) 1/10W J 10k Ω R581 PCB JUMPER D0.6-P5.0 JW5.0T R680 RRXAJR5Z0103 CEMENT RESISTOR(PB FREE) 7W K 5.6 Ω METAL OXIDE FILM RES.
  • Page 57 Ref. No. Description Part No. Ref. No. Description Part No. CHIP RES.(1608) 1/10W F 22k Ω R909 RRXAFR5H2202 RCV401 REMOCON RECEIVE UNIT KSM-602SR2E-2 USESJRSKK045 CARBON RES. 1/4W J 1.5k Ω R911 RCX4JATZ0152 RL601# POWER RELAY SDT-S-112LMR MRNDC12QN014 CHIP RES.(1608) 1/10W F 3.3k Ω R912 RRXAFR5H3301 SA601#...
  • Page 58 Ref. No. Description Part No. CARBON RES. 1/4W J 1.5k Ω R1532 RCX4JATZ0152 CHIP RES.(1608) 1/10W J 100 Ω R1534 RRXAJR5Z0101 CARBON RES. 1/4W J 1.2k Ω R1535 RCX4JATZ0122 CARBON RES. 1/4W J 270 Ω R1538 RCX4JATZ0271 CHIP RES.(1608) 1/10W J 100 Ω R1539 RRXAJR5Z0101 MISCELLANEOUS...
  • Page 59 EWFG2705 L3821UB 2005-07-27...

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