CONTENTS SAFETY PRECAUTIONS................................2 SERVICE HINTS ..................................3 SERVICE POSITION.................................4 ADJUSTMENT PROCEDURE..............................5 ADJUSTMENT PROCEDURE AND SELF-CHECK ........................6 WAVEFORM PATTERN TABLE ...............................7 ALIGNMENT SETTINGS................................8 BLOCK DIAGRAMS ..................................9 PARTS LOCATION .................................14 REPLACEMENT PARTS LIST ..............................15 SCHEMATIC DIAGRAMS ...............................26 CONDUCTOR VIEWS................................32 SAFETY PRECAUTIONS GENERAL GUIDE LINES It is advisable to insert an isolation transformer in the The potential at any point should not exceed AC supply before servicing a hot chassis.
SERVICE HINTS How to remove the rear cover Remove the 12 screws as shown in Fig.2. SCREWS Fig.2. LOCATION OF CONTROLS FOCUS N-BOARD SCREEN C-BOARD K-BOARD H-BOARD Y-BOARD E-BOARD Fig.3.
HOW TO MOVE THE CHASSIS INTO SERVICE POSITION Remove the bead clamper from the mains lead and attach to the degauss coil, shown in Fig.5. Hold and lift the rear of the E-PCB chassis and gently pull the chassis toward you, as shown in Fig.4. Release the respective wiring clips and rotate the chassis horizontally through 90°, anti-clockwise.
ADJUSTMENT PROCEDURE The remote control is used for entering and storing adjustments, with the exception of Cut-off adjustments, which must always be done prior to service adjustment. Perform adjustments in accordance with screen display. The display on the screen also specifies the software version as well as the approx. setting values. The adjustment sequence for the service mode is indicated below.
ADJUSTMENT PROCEDURE Item / Preparation Adjustments Set the +B voltage up as follows:- +B SET-UP Adjust R811 so that B2 shows 148V±1V. Receive a Greyscale signal. Confirm the following voltages. Set the controls :- ± 0,25V ± 0,25V 12 ± 0,5V 33 ±...
WAVEFORM PATTERN TABLE Vert Drive Vert Out VFLB IC451 Pin 2 IC601 Pin 31 IC451 Pin 3 20mS 20mS 20mS H - Out H - Out H - Pulse IC601 Pin 50 IC701 Pin 5 Base Q503 64µS 64µS 64µS HFLB HFLB Video Out...
ALIGNMENT SETTINGS (The figures below are nominal and used for representative purposes only.) Alignment Function Settings / Special features H-Pos Horizontal Position Optimum setting. V-Pos Vertical Position Optimum setting. H-Amp Horizontal Amplitude Optimum setting. V-Amp Vert. Amplitude Optimum setting. E/W-Amp1 EW-amplitude Optimum setting.
VIDEO BLOCK DIAGRAM Y - BOARD E - BOARD Q906 Q908 COILS Q905 Q907 Q909 IC601 61 V IN 1 Q950 Q951 TUNER Q104 IC351 SVM OUT 34 VIDEO PROCESSOR B OUT 39 Q353 Q305 Q306 43 B IN Q105 OUTPUT 42 G IN G OUT 38...
SCHEMATIC DIAGRAMS FOR MODELS TX-28LD4DP / TX-25LD4DP (EURO-4 CHASSIS) IMPORTANT SAFETY NOTICE Components identified by mark have special characteristics important for safety. When replacing any of these components, use only manufacturer's specified parts. NOTE RESISTOR All resistors are carbon ¼W resistor, unless marked otherwise.
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ORDER No. SM-98052 Colour Television TX-28LD4DP TX-25LD4DP Additional information for Self-Check feature FACTORY SETTINGS To return customer settings to factory settings and clear owner ID of all information input by the customer, enter Self-Check mode.Press the down (-/v) button on the customer controls at the front of the TV set, at the same STATUS button on the remote control.