Adjustments - Sony Trinitron CPD-G420 Service Manual

• Landing Rough Adjustment
1. Display all white pattern (or black dot pattern).
2. Set contrast to 255.
3. Display green plain pattern.
4. Side back DY and roughly adjust green plain pattern to be
centered on the useful screen with Purity Magnet.
5. Adjust DY tilt.
Note: Set ROTATION to 128 and LCC_NS to 128 when
adjusting DY tilt.
6. Lightly tighten the DY screw.
• Landing Fine Adjustment
Note: (1) After adjust W/B (9300k), measure the average of ΣIK
with all white video input, while CONTRAST is
maximum and BRIGHTNESS is center. And
adjustment shall be made so that the miss-landing
become least after aging 2H with the IK 30% of
measured value shown above.
(2) The magnetic field shall be BH = 0.
(3) When adjusting at other than BH = 0, calculate the
shifted value from BH = 0.
1. Put the monitor in helmholz coil.
2. Set as follows;
LCC_SW = 0 (LCC Correction Current = 0)
FUNCTION_SW bit1 =
CONTRAST = 255
3. Display green plain pattern.
4. Degauss the iron part of chassis with a hand degausser and
degauss coil.
5. Degauss CRT face with a hand degausser again.
6. Input AC 230V to AC IN and turn the monitor off and on.
Then auto-degauss works.
7. Reset FUNCTION_SW bit1 to 0 (auto-degauss = off)
8. Degauss CRT face with a hand degausser again.
9. Attach wobbling coil to the specified place on CRT neck.
10. With landing checker, adjust DY position, purity, DY center
and landing of the 4 corners.
11. Check landing of the 4 corners, and adjust using magnet if
they are not in the specification.
<Specifications>
Adjust so that the green is within
the specification given right.
4 corner adjust target : within ± 1
The red and blue must be within
the specification given right with
respect to the green.
A difference between red and blue
must be within the specification
given right.
SECTION 4

ADJUSTMENTS

(Auto Degauss = On)
(µm)
0 ± 3 0 ± 7.5 0 ± 3
0 ± 3 0 ± 7.5 0 ± 3
0 ± 3 0 ± 7.5 0 ± 3
(µm)
± 6 ± 6 ± 6
± 6 ± 6 ± 6
± 6 ± 6 ± 6
(µm)
10 10 10
10 7 10
10 10 10
Note: (1) Do not attach more than 2 magnets on one corner.
(2) Attach magnets within the range of 80 - 100 mm from
DY.
(3) Be sure to degauss and check when used magnets.
12. Tighten DY screw within specified torque, and auto-
degauss.
Note: Torque 22 ± 2 kgcm (2.2 ± 0.2Nm)
13. Adjust the vertical angle of DY to make top and bottom pins
equal (a = b). The horizontal angle shall not be changed
(straight). Settle DY upright without leaning, and insert
wedges firmly so that DY shall not move.
<How to place wedge>
Green plain crosshatch pattern
a
c
b
Plaster RTV to both sides for the upper wedge.
Make sure that they settle inside DY.
Plaster RTV to one side for other wedges.
14. Adjust top and bottom pins correction VR.
15. Adjust the horizontal trapezoid distortion by DY horizontal
trapezoid correction VR.
16. Check landing at each corner and in case not in specification,
adjust landing of 4 corners with landing magnet.
17. Remove the sensor and wobbling coil.
18. Switch signals to R, G, and B, and then check that the pure
colors have good color purity.
19. Fix purity magnets with white paint.
4-1
CPD-G420
a and b should be equal.
d
c and d should be equal.