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Tint/Color Adjustment
Service DAC Adjustment (B01) (B00)
Preparation:
1.
Apply a rainbow color bar signal.
2.
Preset the following controls:
• Brightness . . . . . . . .Min.
• Color . . . . . . . . . . . .Center.
• Tint. . . . . . . . . . . . . .Center.
• Picture . . . . . . . . . . .Max.
• Sharpness . . . . . . . .Min.
3.
Set RGB GAMMA (S03) DAC to 0
4.
Connect a jumper from TPD2 to GND (
).
Procedure:
1.
Connect the oscilloscope to TP47B (A-Board).
2.
In the Service Mode, select (B01) DAC Sub-Tint
Adjustment. Adjust until the waveform measured is
as the one shown in Fig. 25.
3.
Connect the oscilloscope to TP47R (TPL1) and
cold GND.
4.
Select DAC Sub-Color Adjustment (B00) and
adjust for peak to peak amplitude to be
0.95Vp-p ±0.1V as shown in Fig. 26.
Remove short jumper and set RGB GAMMA (S03)
DAC to 1.
Color Temperature Adjustment
(B/W Tracking)
Service DAC Adjust.
(C00) (C01) (C02) (C04) (C05)
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 Service Mode for making
electronic adjustments, select Cutoff (C00) RED,
(C01) GRN, (C02) BLU and adjust the picture for
gray.
2.
HIGH LIGHT areas – In Service Mode for making
electronic adjustments, select Drive (C04) GRN,
(C05) BLU and adjust the picture for warm whites.
Complete Adjustment
Preparation:
1.
Turn the Receiver “ON” and allow 30 minutes
warm up at high brightness.
2.
Apply a color bar signal with color “OFF”.
3.
Turn the SCREEN control (part of FBT T551) fully
counterclockwise.
Procedure:
Preset the following Service DACs for best results:
• C0 . . . . . . . . . . . . . . 128
• C1 . . . . . . . . . . . . . 128
• C2 . . . . . . . . . . . . . . 128
• C4 . . . . . . . . . . . . . . 64
• C5 . . . . . . . . . . . . . . 64
1.
Connect the oscilloscope to TPL1 (C-Board).
2.
In Service Mode, select the Sub-Bright DAC (B02).
3.
Press the R-Tune key on the remote.
4.
Observe the oscilloscope waveform at Horizontal
rate and adjust the Service Mode Sub-Bright DAC
(B02) level until a scanning period of 2.4V above
DC ground is measured, as indicated in Fig. 28.
5.
Press the R-Tune key on the remote.
6.
Connect the scope to RED Cathode (KR) on the
CRT-Board.
7.
In the Service Mode, select the RED CUTOFF
DAC (C00).
8.
Press the R-Tune key on the remote.
9.
View scope trace at Horizontal rate and adjust the
Service Mode DAC (C00) level until a scanning
period of 170V above DC ground is measured, as
indicated in Fig. 29.
10. Press the R-Tune key on the remote.
11. Write the same C00 data to C01 and C02.
12. Press the R-Tune key on the remote.
13. Turn the Screen Control (part of FBT) slowly
clockwise until a slightly color horizontal line
appears.
14. Adjust DAC C01 and C02 until the horizontal line
becomes white.
A to B = 1 unit
A
C
1 2 3
10
4 5 6 7 8 9
B
B to C = 2 units
Figure 4. TP47B waveform
TP47B (A-Board)
A
1 2 3 4 5 6
7 8 9 10
Figure 5. TP47R waveform
TP47G (A-Board)
0.95Vp-p±0.1V
0V DC
Figure 6. TPL1 Waveform
2.4V DC