Panasonic TX-25FG20R Service Manual

Preparation1. Receive a colour bar signal with colour “OFF”, and operatethe TV set for more than 30 minutes.2. Set the picture menu to “DYNAMIC NORMAL” and the AI tooff.3. Connect an oscilloscope to TPL5 with DC mode.4. Set the TV set to Market Mode : white balance adjustment(CHK 4).5. Screen VR : Min.6. Set the data level of RGB CUT OFF / DRIVE and SUBBRIGHT.Display : Data LevelR-CUT OFF : 63G-CUT OFF : 128B-CUT OFF : 63R-DRIVE : 128B-DRIVE : 128SUB BRIGHT : 63Adjustment1. Select G-CUTOFF adjustment mode and collapse verticalscan.2. Adjust G-CUTOFF control to become the DC=0 V to videolevel at 180 V as shown in Fig. 1.Fig. 13. Slowly turn the screen control clockwise until a green colourhorizontal line appears on the picture tube. This is thesetting point for the screen control.Note:Do not adjust the G-CUTOFF setting in the followingprocedure.4. Adjust the remaining R and B-CUTOFF controls so as toget a white horizontal line on the screen.5. Return to full field SCAN by pushing the position 5 key onthe remote control.6. Adjust the R-Drive and B-Drive controls as to obtain auniform white on the white bar of the greyscale pattern.7. Confirm correct B/W rendition and greyscale tracking orrepeat CUTOFF and drive control setup.Note:Write down the original value for each address adjustmentbefore adjusting anything.8. Wedge A shown in Fig. 2 should be fixed within a range of45° to the left of the vertical line as shown.9. After inserting wedge A, insert wedges B, C and D.The wedges should be set 90° apart from each other.10. Be certain that the four wedges are firmly fixed and theDeflection Yoke is tightly clamped in place otherwise theDeflection Yoke may shift its position and cause a loss ofconvergence and purity.4.4. WHITE BALANCE (MARKET MODE CHK 4)9TX-25FG20R