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HMD-A230(E)

1-6

3

When one side of the rubber cap is
separated from the anode button, the
anode-cap can be removed by turning up
the rubber cap and pulling up it in the
direction of the arrow 

c

.

•

1

Don’t scratch the surface of anode-caps with sharp shaped
material!

2

Don’t press the rubber hardly not to damage inside of anode-
caps!
A material fitting called as shatter-hook terminal is built in the
rubber.

3

Don’t turn the foot of rubber over hardly!
The shatter-hook terminal will stick out or damage the rubber.

•

NOTE: Short circuit the anode of the picture tube and the anode cap to the metal chassis, CRT shield or carbon painted on the CRT, after

removing the anode.

•

1

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

a

.

2

Using a thumb pull up the rubber cap
firmly in the direction indicated by the
arrow 

b

.

HMD-A230(E)

2-1

Part Replaced (

[)

RV501

When replacing or repairing the shown below table, the following opera-

tional checks must be performed as a safety precaution against X-rays emis-

sions from the unit.

* Confirm one minute after turning on the power.

Using an external DC Power Supply, apply the voltage shown below

between cathode of D517 on D board and GND, and confirm that the

 HV HOLD DOWN circuite works. (TV Raster disappears)

Standard voltage  :  35.90 

      

   V DC

•

Input voltage

: 120 

±

 2 V AC

•

Input signal

:  Cross hatch (white lines on black) at

   69kHz (Primary Mode)

•

Beam control

:  CONT, BRT ;  minimum "0 "

An ammeter in series between FBT 11 pin on D board and GND, then,

decrease gradually the resistance of the variable resistor from

maximum to minimum, and confirm that the Beam Current

Protector Circuite works (TV Raster disappears). The current must

be within the range shown below.

•

Standard current  :  1.55 

        

   mA

•

Input voltage

:  120 

±

 2 V AC

•

Input signal

:  Cross hatch (white lines on black) at 69kHz

•

Beam control

:  CONT, BRT ;  minimum "0"

+0.00
- 0.01

+0.00
- 0.01

HV ADJ

HV Regulator

Circuit Check

HV Protector

Circuit Check

Beam Current
Protector Circuit

Check

Part Replaced (

])

D board           IC501, C532, C534,

          C539, C553, C554,

          C555, C556, C558,

          C561, R540, R541,

          R542, R544, R564,

          R567, R568, RV501,

          T501 (FBT)

D board           IC607, IC901, D515,

                       D517, C540, C542,

                       C544, C951, R510,

R543, R547, R549,

R552, R595,

          T501 (FBT)

D board           IC605,IC607,IC901,

                       C535, C541,R545,

                       R546, R548,R550,

                       R596, R934,

          T501 (FBT)

HMD-A230(E)

2-2

Standard voltage : 179.0 

±

 3.0 V DC

•

Input voltage

:  120 V AC

Note :Use NF power supply or make sure that distortion factor is

          3% or less.

•

Input signal

:  Cross hatch (White lines on black) at 68.7

kHz

•

Beam control

:  CONT : 255 (max), BRT : 255 (max)

HMD-A230(E)

3-1

•

1. Enter the full white signal. (or the full black dots signal)

2. Set the contrast to “CONT”=MAX.

3. Make the screen monogreen.

Note: Off the outputs from R ch and B ch of SG.

4. Reverse the DY, and adjust coarsely the purity magnet so that a green

raster positions in the center of screen.

5. Adjust the "H.CENTER" with the H CENTER Volume .(RV502 on the D

board)

6. Moving the DY forward, adjust so that an entire screen becomes

monogreen.

7. Adjust the tilt of DY, and fix lightly with a clamp.

Note: “TILT” shall be set at 0

•

1. Put the set inside the Helmholtz coil.

2. Set the TLH to the Zero position.

3. Receive the single green signal.

4. Demagnetize the CRT surface with the hand degausser , and perform

auto degaussing.

5. Attach the wobbling coil to the designated part of the CRT neck.

6. Attach the sensor of the landing adjustment unit on the CRT surface.

7. Adjust the DY position and purity, and the DY tilt.

8. Fasten DY with screw.

Note:Torque 22 

±

2kgcm (2.2 

±

 0.2 Nm)

Perform auto degaussing.

Purity Magnet

<<Zero Position>>

L/D control specification

±

 5

±

 5

±

 5

±

 5

±

 5

±

 5

±

 5

±

 5

±

 4

Purity magnet position

±

 4