Screen (G2); Picture Quality Adjustments; 2-6.1. Video Input - Sub Contrast Adjustment - Sony TRINITRON KD-30XS955 Service Manual

(See Section 2-4 Figure 1 - before changing DF/DQP data or
troubleshooting circuit when DF/DQP is suspect.)
Procedure to adjust or check:
1. Short Q8018 B-Gnd to disable DF.
B Mark is on the circuit board. Circuit connection changes should
always be done with the power off.
CAUTION: Q8018 heatsink is live and peak voltage is 250V.
2. Input a cross hatch signal.

2-5. SCREEN (G2)

1. Input composite white fi eld into Video 1.
2. Set to service mode and adjust as follows:
(Fig. 1)
CXA2170P-2 PICO 1-> 0

2-6. PICTURE QUALITY ADJUSTMENTS

Preparation:
• Set PRO MODE (Reset).
1. Input signal (480i Composite):
• Color Bar Video 75 IRE (White) 75% modulation 7.5% Set-up.
• Color Bar RF 75 IRE (White) 75% modulation 7.5% Set-up.
2-6.1. VIDEO INPUT - SUB CONTRAST
ADJUSTMENT
Preparation:
• Input a Color Bar signal to VIDEO 1 (75 IRE 75%).
• Set picture mode: Single (Full) (PRO MODE Reset).
• Picture: Max
• Color: Min
1. Set to Service Mode and adjust as follows:
2170P-2
NO. Name Control Function
01 RGBS R ON
KD-30XS955/34XBR960/34XS955/36XS955
Opeartion Procedure
1) In Full mode, apply changes in Fig. 1
2) Mount G2 adjustment jig. Adjust Cathode
voltage if the standard is not met. Standard
varies by CRT size.
3) Adjust G2 by Flyback transformer (T8001).
4) Return data changes in 1) to original condition.
Avg. Data
4
3. Change CXA2170-P2 item 2 RGBS to 2 to make green only.
1. Overfocus to adjust DQP phase. Adjust the data
(CXA2170-D4 item 8) to balance left and right vertical line width.
2. Once DQP is balanced, remove the short from DF circuit and
refocus the set.
3. Adjust DF (CXA2170-D4 item 7) to balance left and right vertical
line width.
4. Reconfi rm focus performance.
30
QPAM
QPAV
QPAP
QPDC
QPDV
QPDP
DF
DQP
Standards
170 +/- 5 (V )
DC
2. Connect oscilloscope to Pin 1 of CN9001 (R.DRV) on the CX Board.
3. Adjust contrast according to the service mode item: SPIO.
2103-1
NO. Name
02 SCON
white
VR1
(32XS/34XBR/34XS/36XS) = 1.60 ± 0.05 Vpp
4. Write data from Step 3 above, into memory.
KD-30XS955/34XBR960/34XS955/36XS955
34 36
33 45 22
46 47 40
6 6 6
29 42 17
59 63 52
6 6 6
40 36 36
38 37 37
Table 1
Notes
32RDE, 36RDE, 38RFN
Control Function
SUB-CONT
black
VR2
GND
VR
38