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TOSHIBA  2857 DB

Item

Name

Setting(User control)

Input signal

Measurement point

Adjustment procedure

Adjustment standard

[COLP]

SUB

Contrast: MAX

Sub-bright

IC501

1. Select slave address OCH

1.35V(p-p)

COLOUR

Bright: CENTER

signal

#55

[COLP].

 

±

 0.2V(p-p)

PAL

Color: CENTER

(PAL)

(TP501)

2. When [COLP] is selected, Y-signal is muted

and only color signals are outputted.

3. Adjust amplitude of the upper half of the colour

bar output.

[RCUT]

R cut-off

RCUT 40 Hexa-decimal

Screen

1. Set the controls as shown in

[GCUT]

G cut-off

GCUT 40 Hexa-decimal

adjustment

the left column.

[BCUT]

B cut-off

BCUT 40 Hexa-decimal

2. Gradually increase the screen

Screen VR

Screen

GDRV 40 Hexa-decimal

VR (T461) until one of R, G or BDRV B line begins

Select horizontal line mode by

to brighten slightly.

pressing 

-I- - button on the remote

3. Determine the position of the screen VR here.

control in service mode.

4. Adjust RCUT, GCUT and BCUT, brighten other lines

until they begin to light slightly.

(Adjust DATA so that the line becomes almost white.)

5. Press 

-I-- button on the remote control to escape from the

horizontal line mode.

[RCUT]

R cut-off

Contrast: MAX

White, etc.

Screen

1. This adjustment must be done

HIGH LIGHT;

[GCUT]

G cut-off

Bright : CENTER

adjustment

after adjustment of the above-

(103cd/m

3

)

[BCUT]

B cut-off

Color : CENTER

mentioned cut-off and screen

7195K

[GDRV]

C drive

VR’s have been completed.

-0.005uv [BDRV]

[BDRV]

B drive

2. Adjust cut-off and drive DATA

DARK;

(White

alternately.

(17cd/m

3

)

balance)

3. Use a checker to adjust

7695K 

±

 0uv

brightness by changing modulation factor.

ITEM:
Initialisation of QA02 (Memory)

ADJUSTMENT PROCEDURE:
After replacing QA02, the following initialisation
is required.
1. Call up the adjustment mode display following

the steps 1 and 2.

2. Press the CALL button on the Remote Control

and CHANNEL 

 buttons on the TV set

simultaneously. The initialisation of QA02 has
been completed.

3. Check the picture carefully. If necessary,

adjust any adjustment item.

Perform “AUTOMATIC SEARCH MEMORY”

ITEM: SUB-BRIGHTNESS (Address: BRTC)

Note: Constrict the picture height until the
vertical retrace line appears adjusting the
address HIT (HEIGHT).

ADJUSTMENT PROCEDURE:
1. Set CONTRAST to “00,, and BRIGHTNESS to

“50” by adjusting user controls.

2. Set the TV in service mode to get white cross-

bar of inside pattern.

3. Select BRTC (brightness correction), and

adjust the 

 - / + button to reduce the value

so that white portion of inside pattern slightly
light.

4. Adjust 

 - / + button to increase the data

value of BRTC, and set it just before the
difference between the belt of vertical retrace
and the border of black portion of inside
pattern is visible. After that, return vertical
height and contrast.

ITEMS:
HORIZONTAL POSITION ADJUSTMENT
(HPOS)

VERTICAL POSITION ADJUSTMENT (VPOS)

ADJUSTMENT PROCEDURE:
1. Set the TV in service mode, and get black or

white cross-bar signal with VIDEO button on
remote hand unit.

2. Select either HPOS (Horizontal picture phase)

or VPOS (Vertical picture phase) with
CHANNEL 

▼ 

buttons, and adjust horizon-

tal or vertical picture position in the center of
screen with VOLUME 

  - / + buttons.

ITEM:
VERTICAL AMPLITUDE ADJUSTMENT (HIT)

ADJUSTMENT PROCEDURE:
1. Set the TV in service mode, and get black or

white cross-hatch signal with VIDEO button
on remote hand unit.

2. Select HIT (Vertical amplitude) with CHAN-

NEL  

▼ 

buttons, and adjust vertical

amplitude with VOLUME 

 - / + buttons so

that vertical amplitude lacks a little.

3. Adjust vertical amplitude with VOLUME 

 - /

+ buttons so that the first bar on cross-hatch
signal touches edge of screen.

WHITE BALANCE ADJUSTMENT

CUTOFF ADJUSTMENT
(RCUT)
(GCUT)
(BCUT)

DRIVE ADJUSTMENT
(GDRV)
(BDRV)

1. Set Contrast to 40, and brightness to +20 by

picture control.

2. Set the TV in service mode, and get the inside

W/B adjusting signal with VIDEO button.

3. Select RCUT, GCUT and BCUT with CHAN-

NEL  

▼ 

buttons, to set individual values to

32, and to set GDRV and BDRV to 20 with
VOLUME 

 - / + buttons.

4. Press 

 button on the remote control and

rotate Screen VR to get one slight horizontal
line on screen.
Note:Every pressing of 

 button provides

Horizontal line picture and Normal picture
alternately.

5. Press 

 button to release horizontal line

picture, and select the two other colors which
did not light in the above step with CHANNEL

,

▼ 

buttons. Then tap VOLUME 

 - / +

buttons so that three colors slightly light in the
same level.

To correct white balance in light area, select
GDRV and BDRV with CHANNEL 

,

▼ 

buttons

to adjust.

To correct white balance in dark area, perform
fine adjustment of RCUT, GCUT and BCUT.

Light area check (to show white)

Dark area check (to show black)

SELF DIAGNOSTIC FUNCTION
1) Press “9” button on Remote Control during

display of adjustment menu. The diagnosis
will begin to check if interface among IC’s are
executed properly.

2) During diagnosis, the following displays are

shown.

(SELF CHECK)

(1)

2390XXXX

(2)

POWER

:

00

(3)

BUS LINE

:

OK

(4)

Bus CONT

:

OK

(5)

BLOCK

:

UV V1 V2

QV01

1) Part number of microcomputer (QA01)
2) Operation number of protecting circuit ----“00”

is normal. When indication is other than “00”,
overcurrent apts to flow, and circuit parts may
possibly be damaged.

3) BUS LINE CHECK ---- “OK” is normal.

“SDA1-GND” means that SDA line is shorted
to ground.
“SCL1-GND” means that SCL line is shorted
to ground.
“SCL1-SDA1” means that SDA line is shorted
to SCL line.

4) BUS CONT----“OK” is normal.

When indication shows “Q OOO NG”, the
device with the number may possibly be
damaged.

5) BLOCK
UV : TV reception mode
V1: VIDEO 1 input mode  (     1)
V2 :VIDEO 2 input mode  (     2)

Indicated color of mode now selected: Green
and Red
Indicated color of other modes: White
Green: Normal
Red: The microcomputer operates to provide
judgement of no video signal. The red color is
still indicated though the signal is input, failure
may exist in input signal line including QV01.
QV01: In case of indication green --- Normal
In case of indication red with input signal ----
Failure may exist in output line including QV01.

Model name: C5SS (2857DB/3357DB)

Adjustment parts or

Input point/

Adjustment signal

Adjustment conditions and procedures

Bus control item

Output point

Horizontal amplitude

Visual check of picture

WG Philips pattern

1. Conditions: After V. HEIGHT, VERT POSITION

adjustment (WID)

(Bus control)

and H. CENT have been adjusted, set

Pin distortion

Do not use the Philips

the controllers as follows:

compensation amount

pattern of

Contrast: MAX

adjustment (PARA)

FRANCESECAM.

Brightness: Center

Keystone distortion

Color: Center

compensation amount

2. Adjustment procedure

adjustment (HOP)

a. Adjust the horizontal amplitude by the sub address WID.

Adjust so that the left and right white flags of

Philips pattern disappear at the very limits.

b. Make the left and right vertical bars straight by the sub address PARA.

c. Compensate the key distortion by the sub address HOP.

d. Again, adjust the sub address WID.

Sub Data Additional Description

Symbol

Description

HPOS

H screen position correction

HIT

V amplitude adjustment.

LIN

V linearity correction 1.

Linearity balance between top
and bottom screen.

Symbol

Description

VSC

V linearity correction 2.

Linearity balance between top/
bottom and center.

VPOS VPS

V picture position adjustment

VCP

Setting of amount of V amplitude
correction against variation of
screen brightness.

WID

H amplitude adjustment.

Symbol

Description

PARA

H pin-cushion distortion
correction.

CNR

H pin-cushion distortion
correction at four corners.

TRAP

Pedestal distortion correction.

Symbol

Description

HCP

Setting of amount of H amplitude
correction against variation of
screen brightness.

VFC

V linearity correction.
Linearity balance at 1/4, 3/4
areas from top.

Service Mode Cont’d

Содержание 2857 DB

Страница 1: ...lour Making white signal of approx 1Vp p in QA01 Signals W B adjustment Picture Using method White balance adjustment White White balance adjustment check in light area Black part White balance adjustment check in dark area Making approx 1Vp p signal in QA01 Signals Black cross bar White cross bar 2 It is essential that to maintain the safety of the customer all cable forms be replaced exactly as ...

Страница 2: ...ervice mode and get the inside W B adjusting signal with VIDEO button 3 Select RCUT GCUT and BCUT with CHAN NEL buttons to set individual values to 32 and to set GDRV and BDRV to 20 with VOLUME buttons 4 Press button on the remote control and rotate Screen VR to get one slight horizontal line on screen Note Every pressing of button provides Horizontal line picture and Normal picture alternately 5 ...

Страница 3: ...L 29H NICH 00H NICAM THRESHOLD LEVEL 2AH IDL 00H IGR THRESHOLD LEVEL 2BH IDH 00H IGR THRESHOLD LEVEL 20H EVOL 00H EXT PRE VOLUME 2DH EMX FCH NICAM ON LEVEL 2EH EMN 64H NICAM OFF LEVEL 2FH FMA 00H FM ATTENUATOR LEVEL 30H STS 00H STEREO SEPARATION F 31H HPOS 15H 50Hz H POSITION 32H VPOS 04H V POSITION 33H HIT 3EH HEIGHT 37H VLIN 11H V LINEARITY 38H VSC 0FH V S CORRECTION 39H VPS 0EH V SHIFT 3AH VCP ...

Страница 4: ...4 TOSHIBA 2857 DB AV PCB Diagram ...

Страница 5: ...5 TOSHIBA 2857 DB Comb Delay PCB Diagram ...

Страница 6: ...6 TOSHIBA 2857 DB Pro Logic Diagram ...

Страница 7: ...7 TOSHIBA 2857 DB Signal Processing Diagram ...

Страница 8: ...8 TOSHIBA 2857 DB Signal Processing Diagram Cont d ...

Страница 9: ...9 TOSHIBA 2857 DB Power Deflection Diagram ...

Страница 10: ...10 TOSHIBA 2857 DB Power Deflection Diagram Cont d Text PCB Diagram ...

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