Read Sony KV-XF21N90 Service Manual online
– 25 –
KV-XF21N90
RM-915
(3) Screen-corner Convergence
b
a
c
d
a-d : screen-corner
misconvergence
misconvergence
a
d
c
b
a to d : Permalloy assembly
Fix a Permalloy assy
corresponding to the
misconverged areas
corresponding to the
misconverged areas
3-3. FOCUS ADJUSTMENT
Adjust FOCUS control on the flyback transformer for the best
focus.
FLYBACK TRANSFORMER (T503)
2. WHITE BALANCE ADJUSTMENT
1) Set to Service Mode (Refer Section 4-1: ADJUSTMENTS
WITH COMMANDER).
2) Input white raster signal.
3) Set the PICTURE to minimum.
4) Select GCT (WHB 4) and BCT (WHB 5) with
[1]
and
[4]
, and
adjust the level with
[3]
and
[6]
for the best white balance.
5) Set the PICTURE to maximum.
6) Select GDR (WHB 1) and BDR (WHB 2) with
[1]
and
[4]
, and
adjust the level with
[3]
and
[6]
for the best white balance.
7) Write into the memory by pressing
[MUTING]
then
[0]
.
3. SUB BRIGHT ADJUSTMENT
1) Set to service mode.
2) Input a staircase signal of black to white from the pattern
generator.
3) BRIGHTNESS .... 50%.
PICTURE ............ MINIMUM
4) Select SBR (WHB7) with
[1]
and
[4]
, and adjust SBR (WHB7)
level with
[3]
and
[6]
so that the second stripe from the right is
dimly lit.
3-4. G2 (SCREEN) AND WHITE BALANCE
ADJUSTMENTS
1. G2 (SCREEN) ADJUSTMENT
1) Set the PICTURE to normal.
2) Put to VIDEO input mode without signals.
3) Connect R, G and B of the C5 board cathode to the oscilloscope.
4) Adjust BRIGHTNESS to obtain the cathode voltage to the value
below.
5) Adjust G2 (Screen) on FBT until picture shows the point
before cut-off.
White
second from the right
Black
0 V
175 V ±2(VDC)
FOCUS
SCREEN
Click on the first or last page to see other KV-XF21N90 service manuals if exist.