+B Adjustment; Vertical Center Adjustment; Vertical Size Adjustment - Hitachi C21-FL21F Service Manual

+B ADJUSTMENT

PREPARATION
1.
AC input voltage 230 + 5V(50Hz)
2.
Turns on the set and set the brightness
and contrast to Max.
(Signal : Philips Pattern)
3.
After 30 sec heat-run, check & adjust the
+B voltage

VERTICAL CENTER ADJUSTMENT

PREPARATION
1.
Turns on the TV set & heat run about 5 min.
2.
Receive the circular pattern signal
3.
AC 230 + 5V

VERTICAL SIZE ADJUSTMENT

PREPARATION
1.
Turns on the TV set & heat run about 5 min.
2.
Receive the circular pattern signal
3.
Set all picture settings as below.
i.e.
Contrast
Brightness
4.
AC 230 + 1V
: Max
: Center
1.
Adjust R954 to obtain +B voltage as below
95 + 0.5V
Measuring Points
+B voltage : C935 + side
GND
1.
Select the IIC control address No. 54.
2.
Set the horizontal center line to vertical center maker
of CRT by adjustment of IIC.
i.e.
1.
Select the IIC control address No. 55.
2.
Adjust IIC data to obtain the following condition.
i.e.
Picture Top : Inner circle reach the edge of TV raster.
Picture Bottom : Inner circle reach the edge of TV
3.
Receive the NTSC circular signal, and check the
picture size after the above V-size adjustment.
4.
If a> 0mm, go back to IIC control No. 54(V-center
adjustment) and increase the IIC data by 1 position.
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PROCEDURES
: C935 - side
PROCEDURES
Vertical center
marker of CRT
PROCEDURES
PAL
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a
NTSC