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21
CONVERGENCE
2. Turn the green static focus fully clockwise.
(Blooming.)
3. Make the dot at the screen center a true circle
using the 4-pole magnet as shown below.
4. Also adjust the Red and Blue CRT beam shapes
according to the steps (1) to (3).
5. After the adjustment has been completed, return
R,G and B static VRs to the just focus point.
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LENS FOCUS ADJUSTMENT
Preparation for adjustment
1. Receive the Cross-hatch pattern signal.
2. The electrical focus adjustment should have been
completed.
3. Deflection Yoke tilt should have been adjusted.
4. Brightness = 50%
5. Contrast = 60% to 70%
Adjustment procedure
6. Short the 2 pin sub-miniature connector on the
CRT P.W.B. TS, to produce only the color being
adjusted and adjust one at a time. (The adjust-
ment order of R, G and B is just an example.)
7.
(See Figure below)
Loosen the fixing screw on
the lens assembly so that the lens cylinder can be
turned. (Be careful not to loosen the screw too
much, as this may cause movement of the lens
cylinder when tightening.)
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8. Rotate the cylinder back and forth to obtain the
best focus point, while observing the Cross-Hatch.
(Observe the center of the screen).
Hint: Located just below the screen are the two
wooden panels. Remove the panels to allow
access to the focus rings on the Lenses.
9. After completing optical focus, tighten the fixing
screws for each lens.
10. When adjusting the Green Optical focus, be very
careful. Green is the most dominant of the color
guns and any error will be easily seen.
11. Repeat Electrical Focus if necessary.
STATIC FOCUS ADJUSTMENT
Adjustment preparation
1. The lens focus should be finished.
2. Set video conditions to Contrast to MAX and
birightness to 50%.
3. Receive the cross-hatch pattern signal.
4. Apply covers to the lenses of colors other than
the color to be adjusted and project a single
color.
Adjustment procedure
1. Red (R), Green (G) and Blue (B) static focus
adjustment. Vary the static focus VR(focus pack
UFPK) and make the center of the cross-hatch
pattern clearest.
2. Observe the corners of the picture and check that
the focus does not get conspicuously worse.