Set-Up Adjustments; Beam Landing - Sony TRINITRON KV-21FX20A Service Manual

• When complete readjustment is necessary or a new
picture tube is installed, carry out the following
adjustments.
• Unless there are specific instructions to the contrary,
carry out these adjustments with the rated power supply.
• Unless there are specific instructions to the contrary, set the
controls and switches to the following settings :
Contrast ............... 80% [or remote control normal]
Brightness ............... 50%
Preparation:
1. In order to reduce the influence of geomagnetism on the set's
picture tube, face it in an easterly or westerly direction.
2. Switch on the set's power and degauss with the
degausser.

3-1. BEAM LANDING

1. Input an all white signal from the pattern generator.
Set the Contrast and Brightness to normal.
2. Set the pattern generator raster signal to Red.
3. Move the deflection yoke forward and adjust with the purity
control so that the Red is at the centre and the Blue and Green
take up equally sized areas on each side of the screen.
[See Fig.3-1 - 3-3].
4. Move the deflection yoke backwards and adjust so that the
entire screen becomes Red. [See Fig.3-1]
5. Switch the raster signal to Blue, then to Green and verify the
condition.
6. When the position of the deflection yoke has been determined,
fasten the deflection yoke with the screws.
7. If the beam does not land correctly in all the corners, use a
magnet to correct it. [See Fig.3-4]
SECTION 3

SET-UP ADJUSTMENTS

Fig. 3-1
Carry out the following adjustments in this order :
3-1. Beam Landing
3-2. Convergence
3-3. Focus
3-4. White Balance
Note : Test equipment required
1. Color bar/pattern generator.
2. Degausser.
3. Oscilloscope.
4. Digital multimeter.
5. DC Power supply.
Fig. 3-2
Fig. 3-3
GREEN
Purity control corrects
this area
a
c
Deflection yoke positioning
corrects these areas
b
d
Fig. 3-4
16
Purity
RED
BLUE
Disk magnets or
rotatable disk
magnets correct
these areas (a-d)
b
d
a
c