21F3A-T COLOUR TELEVISION Service Manual MODEL : 21F3A-T (THAILAND) ■ Features 54cm pure flat picture tube Auto search 218 program presetting and memory Child lock & on screen help function Haier Group NO:M-AS-TH-21T3A-T-8823 Edition:2003/3/1...
CONTENTS CONTENTS Product Code illumination and Series Introduction --------------------2 Features --------------------------------------------------------------------------------3 Specifications-------------------------------------------------------------------------4 Safety Precautions-------------------------------------------------------------------5 Warning and Cautions--------------------------------------------------------------6 Net dimension------------------------------------------------------------------------12 Parts and Functions----------------------------------------------------------------13 Remote Controller Functions----------------------------------------------------14 Program Diagram--------------------------------------------------------------------15 Maintenance Service and Trouble shooting--------------------------------16 Circuit Diagram-----------------------------------------------------------------------22 Circuit Explanation------------------------------------------------------------------23 Adjustment-----------------------------------------------------------------------------28 Exploded View-------------------------------------------------------------------------34 List of Parts-----------------------------------------------------------------------------35 Damageable Parts List--------------------------------------------------------------45 Information of Resistors and Capacitors-------------------------------------46...
Product Code illumination and Series Introduction Product Code illumination and Series Introduction 21 F 3A – T Compony of Signal processor IC T:Toshiba Model series of cabinet mumber Type of CRT F:pure flat CRT size(unit:inch)
Features Features MODEL MODEL 21F3A-T 21F3A-T FUNCTION FUNCTION ITEM ITEM Thailand Thailand PICTURE SOFTWARE √ Main IC 8823 Digital curtain √ pure flat Slow fading on & off √ PAL NTSC Color system Semitransparent menu √ Audio system Non-flshing channel changing ×...
Specifications Specifications POWER SUPPLY: AC 220V, 50 Hz Tuning system: voltage synthesized type auto-search fine tuning system IF: 38.9MHz Power consumption: 70W Antenna input impedance: 75Ω Receiving system: a) Color system: PAL/NTSC3.58MHz/4.43MHz b) Broadcast TV system: B/G Language displayed: THAILAND Video input: 1.0V (75Ω) Audio input: 436m Vrms (40KΩ)
Safety Precautions Safety Precautions IMPORTANT SAFETY NOTICE Many electrical identify these parts and mechanical parts in this chassis have special safety-related characteristics! In the Schematic Diagram and Replacement Parts List. It is essential that these special safety parts should be replaced with the same components as recommended in this manual to prevent X-RADIATION, Shock, Fire, or other Hazards.
Warning and Cautions Warning and Cautions 1. When you clean the TV set, please pull 4. To prevent the TV set from firing and out the power plug from AC outlet. Don't electric shock, don't clean the cabinet and the screen with make the TV set rain benzene, petrol and other chemicals.
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Warning and Cautions General Servicing Precautions 1. Always unplug the receiver AC power cord from the AC power source before: a. Removing or reinstalling any component, circuit board module or any other assembly of the receiver. b. Disconnecting or reconnecting any receiver electrical plug or other electrical connection.
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Warning and Cautions components are usually called Electrostatic ally Sensitive (ES) Devices. Examples of typical ES devices are integrated circuits and some field effect transistors and semiconductor “chip” components. The following techniques should be used to help reduce the incidence of component damage caused by static electricity.
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Warning and Cautions a. Allow the soldering iron tip to reach normal temperature. (500 F to 600 b. Heating the component lead until the solder melts. c. Quickly draw the melted solder with an anti-static, suction-type solder removal device with solder braid. CAUTION: Work quickly to avoid overheating the circuit board printed foil.
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Warning and Cautions Connect the replacement transistor leads to the corresponding leads extending from the circuit board and crimp the “U” with long nose pliers to insure metal to metal contact then solder each connection. Power Output, Transistor Device Removal/Replacement Heat and remove all solder from around the transistor leads.
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Warning and Cautions copper as absolutely necessary). 2. Carefully scratch away the solder resist and acrylic coating (if used) from the end of the remaining copper pattern. 3. Bend a small “U” in one end of a small gauge jumper wire and carefully crimp it around the IC pin.
Parts and Functions Parts and Functions 1.Front panel of the TV set Headphone socket MENU MENU TV/AV TV/AV - VOL + - VOL + Volume Menu TV/AV up/ down Channel switch position up/down audio VIDEO VIDEO Video Signal receiver Power indicator 2.Rear panel of the TV set VIDEO AUDIO...
Remote Controller Functions Remote Controller Functions Buttons and Descriptions TV and AV Exchange Button To exchanger between TV and TV/AV other available video inputs Mute Button Press to conceal the sound of programs. DISP SYSTEM -/-- SCAN Screen Display Button System Adjust Button Direct-digit Choosing Button Directly select channel numbers...
Program Diagram Program Diagram Insert the power plug into the power line socket and insert the antenna plug into the antenna socket on the rear panel. Press down the power switch of the TV set. The red indicator light goes on. If no picture appears, press the button on the remote controller.
Maintenance Service and Trouble shooting Maintenance Service and Trouble shooting A. Principle integrated circuits A1. 21F3A-T color TV set composed of the following sections (1) Small signal processing: super monolithic integrated circuits N204(TMPA8823CSN). and memory N901 (AT24C08). (2) Sound power amplifying: integrated circuits N701 ( TDA2611).
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Maintenance Service and Trouble shooting A3. Error Detection Process No light and sound Check to see if Fuse is normal Abnormal Normal Check to see 110V、180V Check VD503~VD506, etc. voltage is normal C507, V513, etc. Normal Abnormal Check to see if the T est to see all terminal collector voltage of V552 Resistance of load...
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Maintenance Service and Trouble shooting Maintenance Service and Trouble shooting No raster Whether G2 voltage is normal Abnormal Normal Test filament voltage Test the base voltage of V444 Normal Abnormal Normal Abnormal Check to see if be Heater Resistor Check the voltage Check the circuit open voltage of V411 is...
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Maintenance Service and Trouble shooting Horizontal bright line Make R328 open. Multimeter is at range RΧ1K. Red probe connects to ground. Touch No.5 of N402 with black probe. Bright line flashes for a moment Check to see if voltage of pin6 at Check to see if the voltage N402 is normal of pin 15 and pin16 of...
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Maintenance Service and Trouble shooting Picture exists but no sound Make C703 open. Multimeter is at band RΧ1K. Red probe connect to ground. Touch No.7 of N701 with black probe No noise Have noise Make V701 collector open. Touch Power amplifier is abnormal. No.7of V701 with black probe to Inspect N701 and peripheral see if noise exists...
Maintenance Service and Trouble shooting Troubleshooting Before calling service personnel, please check the following chart for a possible cause to the trouble you are experiencing. Symptom Check these things TV is not Be sure the power cord is plugged in. turned on The MUTE function may be used.
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Circuit Explanation 3.Pane hint picture Sound Power Amplifier Picture/Sound IF Amplifier, Video and audio signal Processing, RGB Output Circuits and H &V Sync pulse Horizontal Scan segregation Output Vertical Scan Output Main Processor Audio/Video In/Out Infrared Receiver Remote Controller...