Sony Trinitron KV-20S90, Service Manual

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KV-20S90 / 21SE43C
DYNAMIC CONVERGENCE ADJUSTMENT
Before performing this adjustment, perform Horizontal and Vertical Static
Convergence Adjustment.
1. Slightly loosen defl ection yoke screw.
2. Remove defl ection yoke spacers.
3. Move the defl ection yoke for best convergence as
shown below:
R G B B G R
R G B
R
R
R
G
B
G B
G
B
R G B
B G R
R
G
B
R
G
B
B G R R G B
4. Tighten the defl ection yoke screw.
5. Install the defl ection yoke spacers.
SCREEN-CORNER CONVERGENCE
1. Affi x a permalloy assembly corresponding to the misconverged areas:
b a
c d
a
b
a-d: screen-corner
misconvergence
c
d
2-3. FOCUS
1. Adjust FOCUS control for best pictures.
2-4. SCREEN (G2)
1. Input a dot pattern.
2. Set the PICTURE and BRIGHTNESS controls at minimum and
COLOR control at normal.
3. Adjust SBRT, GCUT, BCUT in service mode with an oscilloscope as
shown below so that voltages on the red, green, and blue cathodes
are 170 ± 2 VDC.
pedestal
GND
170 ± 2 VDC
4. Observe the screen and adjust SCREEN (G2) VR to obtain the faintly
visible background of dot signal.
Focus (FV)
Screen (G2)