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1.  Discharge the anode of the CRT and remove 

the anode cap.

2.  Unplug all interconnecting leads from the 

defl ection yoke, neck assembly, degaussing 
coils and CRT grounding strap.

3.  Remove the C Board from the CRT.

4.   Remove the chassis assembly.

5.  Loosen the neck assembly fi xing screw and 

remove.

6. Loosen 

the 

defl ection yoke fi xing screw and 

remove.

7.  Place the set with the CRT face down on 

a cushion and remove the degaussing coil 
holders.

8.  Remove the degaussing coils.

9.  Remove the CRT grounding strap and spring 

tension devices.

10. Unscrew the four CRT fi xing screws [located on 

each CRT corner] and remove the CRT  [Take 
care not to handle the CRT by the neck].

WARNING: High voltage remains in the CRT even after the power is disconnected. To avoid electric shock, discharge CRT before attempting to  remove 
the anode cap.  Short between anode and coated earth ground strap of CRT. 
NOTE:  After removing the anode cap, short circuit the anode of the picture tube and the anode cap to either the metal chassis, CRT shield, or carbon 
painted on the CRT. 

1.  Do not use sharp objects which may cause damage to the surface of the 

anode cap. 

2.  To avoid damaging the anode cap, do not squeeze the rubber covering too 

hard. A material fi tting called a shatter-hook terminal is built into the rubber. 

3.  Do not force turn the foot of the rubber cover. This may cause the shatter-

hook terminal to protrude and damage the rubber.

Turn up one side of the rubber cap in 
the direction indicated by arrow  a  .

Use your thumb to pull the rubber
cap fi rmly in the direction indicated
by arrow  b  .

When one side of the rubber cap separates from 
the anode button, the anode cap can be removed 
by turning the rubber cap and pulling it in the 
direction of arrow  c  .

a

b

Anode Button

c

4

1

10

9

8

7

6

3

5

2

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.

Set the controls as follows unless otherwise noted:

Picture control 

NORMAL

Brightness control  NORMAL

 

1.  Beam Landing

 

2.  Convergence

 

3.  Focus

 

4.  Screen (G2)

 

5.  White Balance

 

1.  Color Bar Pattern Generator

 

2.  Degausser

 

3.  DC Power Supply

 

4.  Digital Multimeter

Before beginning adjustment procedure:
1.  Feed in the white pattern signal.
2.  In order to reduce the geomagnetism on the set’s picture tube, face 

it east or west.

1.  Input a raster signal with the pattern generator.
2.  Loosen the deflection yoke mounting screw, and set the purity 

control to the center as shown below:

Purity control

3.  Turn the raster signal of the pattern generator to green.
4.  Move the deflection yoke backward, and adjust with the purity 

control so that green is in the center and red and blue are even on 

both sides. 

Red

Blue

Green

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

screen becomes green. 

6.  Switch over the raster signal to red and blue and confirm the 

condition.

7.  When the position of the deflection yoke is determined, tighten it 

with the deflection yoke mounting screw.

8.  If landing at the corner is not right, adjust by using the disk 

magnets. 

Purity control

corrects this area.

Disc magnets or rotatable
disc magnets correct these
areas (a-d).

Deflection yoke positioning
corrects these areas.

a

b

b

c

c

d

d

a

 

5.  Oscilloscope

 

6.  Landing Checker

 

7.  XCV Adjuster

Before starting convergence adjustments:
1  Perform FOCUS, VLIN and VSIZE adjustments.
2.  Set BRIGHTNESS control to minimum.
3.  Set Picture mode to STANDARD.
4.  Feed in dot pattern.

1.  Adjust the 4 pole magnet to converge red, green and blue dots in 

the center of the screen. 

Center dot

R    G    B

R
G
B

4 pole magnet

RV750
H. STAT

C/CV Board

2.  Tilt the 4 pole magnet and adjust static convergence to open or 

close the 4 pole magnet.

 

When the 4 pole magnet is moved in the direction of arrow 

A

 and 

B

, the red, green, and blue dots move as shown below:

R

R

G

G

B

B

A

B

B

A

B

R

G

G

R

B

If the blue dot does not converge with the red and green dots, use the 6 

pole magnet to adjust as shown:

R G

B

R

G

B

R

G B

R

B

R

G

G

G

B

R

B

6 Pole Magnet

6 Pole

Magnet

4 Pole

Magnet

DY pocket

Purity

4 Pole Magnet

Before performing this adjustment, perform Horizontal and Vertical Static 

Convergence Adjustment.

Input cross hatch pattern.
 

a)  TLH

 

Adjust the horizontal convergence of red and blue dots by inserting 

TLH Correction Plate to the DY pocket (left or right).

 

b)  YCH

 

Adjust YCH to balance Y axis.

 

c)  TLV

 

Adjust YCh to balance Y axis.

 

d)  XCV

 

Adjust XCV to balance X-axis.

TLV

R B

YCH

R

B

XCV

B

R

TLH

B

R

YCH

DY pocket

DY pocket

XCV

TLV

XCV

TLV

TLH Plate

ON DY:

Affix a Piece A (90), Convergence Correct/Permaloy Assy Correction to 

the misconverged areas. 

b

a

c

d

a-d : screen-corner
        misconvergence

a1

b1

c1

d1

a1~d1:Piece A (90), Convergence Correct

or

Permaloy Assy Correction

FOCUS adjustment should be completed before White Balance 

adjustment. (See 4-4. White Balance Adjustment)

1.  Receive digital monoscope pattern.
2.  Set Picture Mode to “DYNAMIC”.
3.  Adjust focus VR to obtain a just focus at the center of the screen.
4.  Change the receiving signal to white pattern and blue back.
5.  Confirm magenta ring is not noticeable. In case magenta ring is 

obvious, then adjust FOCUS VR to balance magenta ring and 

FOCUS.

SCREEN

FOCUS