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– 13 –

•

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

3. 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.)

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

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

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

condition.

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

fasten the deflection yoke with the screw.

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

magnet to adjust it.

(See Figure 3-4.)

Purity coutrol

Deflection yoke positioning

corrects these areas.

Purity control corrects

this area.

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

b  

c

a

d

b

a

c

d

GREEN

BLUE      RED

Purity Control

}

normal

– 14 –

R     G     B

G

R

B

Center dot

V.STAT Magnet

C board

RV 701

SCREEN (G2)

•

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 points are on top of each other at the center of

the screen.

2. (Moving horizontally), adjust the H.STAT magnet so that the

red, green and blue points are on top of each other at the center

of the screen.

3. Tilt the V.STAT magnet and adjust the static convergence by

opening or closing the V.STAT magnet.

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 V.STAT magnet.

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

below.

•

Operation of BMC (Hexapole) magnet.

If the blue or red point does not converge with the other two

points, perform following steps:

Move BMC magnet (a) to correct insufficient H.static

convergence.

Rotate BMC magnet (b) to correct insufficient V.static

convergence

In either case, repeat Beam Landing Adjustment.

a

BMC magnet

b

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.

a-d : screen-corner
misconvergence

b

a

c

d

B     G     R

B

 

G

 

R

R

 

G

 

B

R     G     B

R     G     B

R

 

G

 

B

B

 

G

 

R

B     G     R

R     G     B

B     G     R

B     G     R

R     G     B

a

d

c

b

Fix a Permalloy assy
corresponding to the
misconverged areas

Permalloy assembly

– 16 –

Adjust FOCUS control on the flyback transformer for the best

focus.

Note: Screen VR is not use.

SERVICE

MUTING

1 F

DATA

RDR

Adjustment Item

09

Item number

WRITE

1 F

RDR

09

0

Executes the writing

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 the 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

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 - .

0 V

177 ± 2 V DC

FOCUS

SCREEN
(NOT USED)

FLYBACK TRANSFORMER (T851)

177±2V