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PC to allow a Schematic Diagrams Self Check number of diagnostic and control functions to Service Hints be performed. Mechanical For more details contact View your local Panasonic Disassembly company. PCB Views Location of Controls EXIT BACK Waveforms Supplementary Information...
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Audio Control Power supply Video BACK E - Schematics H - Schematic E - PCB Y - PCBs Y - Schematics BACK BACK...
Specifications are subject to change without notice. Weights and dimensions shown are approximate. NOTE: This Service Manual should be used in conjunction with the EURO4 Technical guide. Panasonic CS ( U.K. ) Ltd. WILLOUGHBY ROAD, BRACKNELL, BERKS., RG12 8FT. 3DQDVRQLF...
Set the brightness to minimum. 20M ohm. When the exposed metal does not have a Measure the high voltage. The meter should indicate. return path to the chassis, the reading must be TX-28MD4 28,5kV ± 1kV. infinite. TX-25MD4 28,2kV ±...
SERVICE HINTS How to remove the rear cover Remove the 9 screws as shown in Fig.2. SCREWS Fig.2. LOCATION OF CONTROLS FOCUS SCREEN E-BOARD H-BOARD Y-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 +B SET-UP Set the +B voltage up as follows:- Adjust R811 so that B2 shows 148V±1V [130V±1V Receive a Greyscale signal. TX-21MD4] Set the controls :- Confirm the following voltages. ± 0,25V ± 0,25V Brightness Minimum 12 ±...
WAVEFORM PATTERN TABLE Vert Drive VFLB Vert Out IC451 Pin 3 IC451 Pin 2 IC601 Pin 31 20mS 20mS 20mS H - Out H - Out H - Pulse IC601 Pin 50 IC701 Pin 5 Base Q503 64 S 64 S 64 S HFLB HFLB...
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 E - BOARD Y - BOARD TX-28MD4 TX-25MD4 Q906 Q908 COILS ONLY TX-28MD4 TX-25MD4 Q905 Q907 Q909 ONLY IC601 61 V IN 1 Q950 Q951 TUNER Q104 IC351 SVM OUT 34 VIDEO PROCESSOR B OUT 39 Q353...
REPLACEMENT PARTS LIST Important Safety Notice Components Identified by mark have special characteristics important for safety. * When replacing any of these components, use only manufacturers specified parts. In case of ordering these spare parts, please always add the complete Model-Type number to your order.
SCHEMATIC DIAGRAMS FOR MODELS TX-28MD4 / TX-25MD4 / TX-21MD4 (EURO-4 CHASSIS) IMPORTANT SAFETY NOTICE Components identified by mark have special characteristics important for safety. When replacing any of these components, use only manufacturers' specified parts. NOTE RESISTOR All resistors are carbon ¼W resistor, unless marked otherwise.
ORDER No. SM-98051 Colour Television TX-28MD4 TX-25MD4 TX-21MD4 Additional information for Self-Check feature (Information in brackets {} refers to the TX-21MD4) FACTORY SETTINGS To return customer settings to factory settings and clear owner ID of all information input by the customer, enter Self-Check mode.
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This datasheet has been downloaded from: www.DatasheetCatalog.com Datasheets for electronic components.
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