Sony TRINITRON KV-A2121D Service Manual page 23

(3) Screen corner convergence
a-—d: screen-corner
convergence defect
Install the permalloy assembly for the section
with faulty.
Permalloy
3-3. FOCUS
Adjust the focus to optimize the screen.
FOCUS
3-4. WHITE BALANCE
[ Screen G2 setting ]
Input the dot signal from the pattern generator.
Set the picture brightness control to its lowest
level.
Apply 170V DC to the R, G, and B cathodes
with an external power supply.
While watching the picture, adjust G2 control
RV701 (Screen) to the point just before the
return lines disappear.
[ White balance adjustment ]
1.
Input an all-white signal from the pattern
generator.
Set the picture brightness and color controls to
their normal levels.
Use the RV704 (B Drive) and RV703 (G Drive)
to adjust white balance.
In the adjustments below, have the picture color and
brightness settings at their normal levels unless there
is a specific instruction to the contrary.
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