Panasonic tx-34p180b Service Manual

Panasonic tx-34p180b Service Manual Manual pdf 14 page image

5.7. COLOUR PURITY1. Operate the TV set for over 60 minutes.2. Receive a purity pattern signal. (white pattern)3. Set Bright and Contrast controls to their maximumpositions.4. Set V-POS to 63 DAC.5. Adjust roughly the static convergence magnets.6. Fully degauss the picture tube using an externaldegaussing coil.7. Loosen a clamp screw for the deflection yoke and move thedeflection yoke as close to the purity magnet as possible.8. Adjust the purity magnet so that a vertical green field isobtained at the center of the screen.9. Slowly press the deflection yoke and set it where a uniformgreen field is obtained.10. Adjust roughly the Low Light controls and make sure that auniform white field is obtained.11. Tighten the clamp screw.5.8. CONVERGENCE1. INSTRUMENTa. Helmhortz device2. PREPARATIONa. Set the Helmhortz device to local magnetic field.Horizontal: 0 ± 0.03 x10 -4 Tb. Receive the cross hatch pattern.c. Picture menu: DYNAMIC Normal and adjust BRIGHTDAC until gray portion of cross hatch.d. Set DY to CRT not to tilt (up and down and left andright).3. ADJUSTMENTa. Static convergence Adjustmenta. Make sure that magnets are positioned shown inFig. 1.b. Adjust 4-pole magnets (Fig. 1) to align center dots ofR and B and adjust 6-pole magnets to align centerdots to G.c. After adjustment, secure magnets with magnet lockof white lacquer.*Beams move with rotating when static magnets areturned.Rotational reduce of beams differs by angle of twomagnets.Therefore, repeat magnet adjustmentsseveral timesso that all are aligned completely.Fig. 1b. YHC, YV, XV, Adjustment (Fig. 2)a. Adjust so that Static and Dynamic convergence isbest with YHC, VR, YV and XV coil.In case of static convergence is tilted, repeat (1)Static convergence Adjustment.Fig. 2c. Dynamic convergence Adjustmenta. When dynamic convergence is bad, fixing permalloybetween neck and DY so that dynamic convergenceis best.4. Confirm that left upper side line is straight.When left upper side line isn’t straight, put magnet on DYand adjust the left upper side line to straight.14TX-34P180B