Panasonic CT-32HX40CB, Руководство по обслуживанию

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Service Adjustments (Electronic Controls, cont.)
7. Connect the oscilloscope to TP47B.
8. In Serviceman Mode adjust “B-Y G” data so that
the amplitude “b” is 1.35
±
0.03V. (See Fig. 28)
9. With oscilloscope still connected to TP47B, adjust
“TINT” data so that the peak WHITE is located at
same level as peak “3”, within 0
±
0.03V, then
increase “TINT” data by 3 steps.
10. Connect oscilloscope to TP47G.
11. In Serviceman Mode adjust “COLOR” data so that
the amplitude “c” is 1.4
±
0.03V. (See Fig. 29).
12. Apply a studio color bar pattern and confirm that
saturation and phase are normal (normal image).
Color Temperature Adjustment
(B/W Tracking)
Serviceman DAC Adjust. (CUT R) (CUT G) (CUT B)
(R DR) (B DR)
Minor Touch-Up Method
OBSERVE low and high brightness areas of a B/W
picture for proper tracking. Adjust only as required for
“good gray scale and warm highlights”.
1.
LOW LIGHT areas – In Serviceman Mode for
making electronic adjustments, select CUT R, CUT
G, CUT B and adjust the picture for gray.
2. HIGH LIGHT areas – In Serviceman Mode for
making electronic adjustments, select Drive R DR,
B DR and adjust the picture for warm whites.
Complete Adjustment
Preparation:
1.
Turn the Receiver “ON” and allow 30 minutes
warm up at WHITE PATTERN.
2. Apply a white balance pattern.
3. Set Picture controls to Normalized.
4. Turn the SCREEN control (part of FBT T551) fully
counterclockwise.
5. Preset the following Serviceman DACs for best
results:
• CUT R . . . . . . . . . . 0 00
• CUT G . . . . . . . . . . .2 80
• CUT B . . . . . . . . . . 0 00
• R DR . . . . . . . . . . . . . 40
• B DR . . . . . . . . . . . . . 40
Procedure:
1.
Connect the oscilloscope to TP35 (CRT-Board).
2. In Serviceman Mode for making electronic
adjustment, select “BRIGHT” DAC.
3. Press RECALL button on the Remote Control to
collapse the raster. (Service SW).
4. Observe oscilloscope waveform and adjust
serviceman mode “BRIGHT” DAC until
2.3V ±0.05V above DC ground is measured
(See Fig. 30)
5. Press RECALL button on the Remote to restore
the raster.
6. Connect scope to GRN Cathode (KG) on
CRT-Board
7. In Serviceman mode for making electronic
adjustments, select CUT G DAC.
8. Press RECALL button on the Remote to collapse
the Raster (Service SW).
9. View scope trace at Horizontal rate and adjust
Serviceman Mode “CUT G” DAC for the scanning
period to be 170 ± 2V above DC ground
(See Fig. 31.)
10. Remove the prove of the oscilloscope.
11. Turn SCREEN VR (Part of FBT) slowly clockwise
until a faint green horizontal line appears.
12. Using the other two colors Serviceman Mode DAC
CUT R and CUT B change their setting to produce
a white horizontal line.
13. Press RECALL button on the Remote Control to
restore full raster.
14. Confirm a good gray scale by viewing B/W color
bar Pattern.
15. In serviceman Mode select DAC DRIVE
adjustment “R DR” and “B DR” and adjust for warm
white in white color bar of pattern.
16. If correction is needed perform Minor Touch-Up
Method.
WHITE
1
2
3
4
5
6 7
8
9
10
"b"
Figure 28. TP47B waveform
1.35
±
0.03V
1 2
3
4
5 6
7
8
9
10
c
WHITE
Figure 29. TP47G waveform
1.4
±
0.03V
0V DC
Figure 30. TP35 Waveform
2.3V±0.05V DC
Figure 31. GK Waveform
Cathode Waveform.
170V±2VDC
0V DC
(Ground)