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•

The following adjustments should be made when a complete

realignment is required or a new picture tube is installed.

•

These adjustments should be performed with rated power

supply voltage unless otherwise noted.

Controls and switch should be set as follows unless otherwise noted:

PICTURE control ...........................................................  normal

BRIGHTNESS control ...................................................  normal

Perform the adjustments in the following order :

1. Beam Landing

2. Convergence

3. Focus

4. White Balance

Note :  Test Equipment Required.

1. Color-bar/Pattern Generator

2. Degausser

3. Oscilloscope

.................................................................................................................................................................................................................................

•

In order to reduce the influence of geomagnetism on the set's

picture tube, face it east or west.

•

Switch on the power and degauss with the degausser.

1. Input a white signal with the pattern generator.

Contrast

Brightness

2. Position neck assy as shown in Figure 3-1.

3. Set the pattern generator raster signal to a green raster.

4. Move the deflection yoke to the rear and adjust with the  purity

control so that the green is at the center and the blue and the red

take up equally sized areas on each side.

(See Figures 3-1 through 3-3.)

5. Move the deflection yoke forward and adjust so that the entire

screen is green. (See Figure 3-1.)

6. Switch the raster signal to blue, then to red and verify the

condition.

7. When the position of the deflection yoke has been decided,

fasten the deflection yoke with the screw.

8. If the beam does not land correctly in all the corners, use a

magnet to adjust it.

(See Figure 3-4.)

GREEN

BLUE      RED

Purity control

}

normal

Neck assy

G1   G2   G3

Deflection yoke positioning

corrects these areas.

Purity control corrects

this area.

Disk magnets or rotatable
disk magnets correct
these areas (a-d).

a

c

b

d

a

b

c

d

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•

The respective dot positions resulting from moving each magnet

interact, so be sure to perform adjustment while tracking.

Use the V. STAT magnet to adjust the red, green and blue dots

so they coincide at the center of screen (by moving the dots in

the horizontal direction).

•

Operation of the V.STAT magnet.

If the V.STAT magnet is moved in the direction of the a and
b arrows, the red, green and blue dots move as shown below.

B

R

B

R

a

b

b

b

a

b

a

b

a

R

G

B

b

B

G

R

b

b

a

a

1

2

3

G

G

B     G     R

R     G     B

•

Operation of BMC (Hexapole) Magnet.

To align or balance the red, green and blue dots, adjust the BMC

(Hexapole) magnet as shown below.

R G

B

R

G

B

R

G B

R

G

B

R

G

B

R

G

B

•

Before starting this adjustment, adjust the focus, horizontal size

and vertical size.

•

Minimize the brightness setting.

•

Provide dot pattern.

1. (Moving vertically) adjust the V.STAT magnet so that the red,

green  and blue dots in the center of the screen are separated

from each other.

2. Adjust the BMC (Hexapole) magnet so that the red, green and

blue dots are aligned in a straight line.

3. Adjust the BMC (Hexapole) magnet so that the red, green and

blue dots are balanced (ie. equal distance) on either side of the

green dot.

4. (Moving Horizontally) adjust the V.STAT magnet so that the

red, green and blue dots converge on top of each other in the

center of the screen.

R     G     B

G

R

B

Center dot

RV 701

SCREEN (G2)

C board

V.STAT Magnet

BMC (Hexapole)

V.STAT

Purity

– 15 –

3. Move the deflection yoke as shown in the figure below and

optimize the convergence.

4. Tighten the deflection yoke screws.

5. Install the deflection yoke spacer.

•

Before starting this adjustment, adjust the horizontal static

convergence and the vertical static convergence.

1. Slightly loosen the deflection yoke screws.

2. Remove the deflection yoke spacer.

R

G

B

R

G

B

R

G

B

R

G

B

R

G

B

R

G

B

R

G

B

R

G

B

R

G

B

R

G

B

R

G

B

R

G

B

a-d : screen-corner
misconvergence

b

a

c

d

Fix a Permalloy assy
corresponding to the
misconverged areas

Permalloy assembly

a

b

c

d

– 16 –

Adjust FOCUS control on the flyback transformer for the best

focus.

SERVICE

MUTING

1 F

DATA

RDR

Adjustment Item

09

Item number

WRITE

1 F

RDR

09

0

Executes the writing

1) Set the PICTURE and BRIGHTNESS to normal.

2) Put to VIDEO input mode without signals.

3) Connect R, G and B of the C board cathode to the oscilloscope.

4) Adjust G2 (RV701) volume to the value below.

1) Set to Service Mode.

2) Input an entire white signal.

3) Set the PICTURE to maximum.

4) Select RDR(09) with  1  and  4 , and then set the level to 25

with  3  and  6 .

5) Select GDR(0A) and BDR(0B) with  1  and  4  and adjust

the level with  3  and  6  for the best white balance.

6) Write into the memory by pressing  MUTING  

→

 then  - .

175 V DC

0 V

177 ± 2 V DC

Focus

Set the standby condition (Press  POWER  button on the

commander) and then press  POWER  button again, hereupon it

becomes TV mode.

1) Set to Service Mode.

2) Press  1  (UP) and 4   (DOWN) to select an item of

adjustments.

3) Press  MUTING  button and it will indicate WRITE on screen.

4) Press  -  button to write into memory.

1) After adjustment, pull out the plug from AC outlet, and then

plug into AC outlet again.

2) Turn the power switch ON and set to Service Mode.

3) Call the adjusted items again to confirm adjustments were made.

Item
number

Note

Adjustment
item

Initial DATA

09

RDR

25

WHITE POINT R

0A

GDR

20

WHITE POINT G

0B

BDR

20

WHITE POINT B