Toshiba 2857DD User manual

TOSHIBA
FILE
NO.
030-9530
SERVICE MANUAL
COLOUR
TELEVISION
C5SS Chassis
285/DD

SAFETY INSTRUCTIONS
WARNING:
BEFORE
SERVICING
THIS
CHASSIS,
READ
THE
"X-RAY
RADIATION
PRECAUTION",
"SAFETY
PRECAUTION”
AND
"PRODUCT
SAFETY
NOTICE"
INSTRUCTIONS
BELOW.
X-RAY RADIATION PRECAUTION
. The E.H.T. must be checked every time the
receiver is serviced to ensure that the C.R.T. does
not emit X-ray radiation as result of excessive
E.H.T. voltage. The nominal E.H.T. for this receiver
is 31.5 kV at zero beam current (minimum
brightness) operating at 220V a.c. The maximum
E.H.T. voltage permissible in any operating
circumstances must not exceed 32.0 kV. When
checking the E.H.T., use the ‘High Voltage Check’
procedure in this manual using an accurate E.H.T.
voltmeter.
2. The only source of X-RAY radiation in this receiver
is the C.R.T. To prevent X-ray radiation, the
replacement C.R.T. must be identical to the original
fitted as specified in the Parts List.
. Some components used in this receiver have safety
related characteristics preventing the C.R.T. from
emitting X-ray radiation.
For continued safety, replacement component
should only be made after referring the Product
Safety Notice below.
SAFETY PRECAUTION
. This receiver has a nominal working E.H.T. voltage
of 28.5 kV. Extreme caution should be exercised
when working on the receiver with the back
removed.
Do not attempt to service this receiver if you are
not conversant with the precautions and procedures
for working on high voltage equipment.
When handling or working on the C.R.T., always
discharge the anode to the receiver chassis before
removing the anode cap
The C.R.T., if broken, will violently expel glass
fragments. Use shatter proof goggles and take
extreme care while handling.
Do not hold the C.R.T. by the neck as this is a very
dangerous practice.
2. It is essential that to maintain the safety of the
customer all cable forms be replaced exactly as
supplied from factory.
3. A small part of the chassis used in this receiver is,
when operating, at approximately half mains
potential at all times. It is therefore essential in the
interest of safety that when serving or connecting
any test equipment the receiver should be supplied
via a suitable isolating transformer of adequate
rating.
. Replace blown fuses within the receiver with the
fuse specified in the parts list.
. When replacing wires or components to terminals
or tags, wind the leads around the terminal before
soldering. When replacing safety components
identified by the international hazard symbols on
the circuit diagram and parts list, it must be a
Toshiba approved type and must be mounted as
the original.
. Keep wires away from high temperature compo-
nents.
PRODUCT SAFETY NOTICE
Many electrical and mechanical components in this chassis have special safety-related characteristics. These
characteristics are often passed unnoticed by a visual inspection and the X-ray radiation protection afforded by
them cannot necessarily be obtained by using replacements rated at higher voltages or wattage, ett.
Components which have these special safety characteristics in this manual and its supplements are identified by
the international hazard symbols on the schematic diagram and parts list. Before replacing any of thes=
components read the parts list in this manual carefully. Substitute replacement components which do not have
the same safety characteristics as specified in the parts list may create X-ray radiation.

FRONT CONTROLS AND REAR VIEWS
» Oey
ANY
(VIDEO-3)
S-VIDEO TERM. MAIN SW.
VIDEO-3 POWER IND.
HEAD PHONE ON-TIMER IND.
POSITION UP
POSITION DOWN
VOLUME UP
VOLUME DOWN
MENU
a ee? |
o a a
7 HL
—_ YL =|
- oO
TOSHIBA
5
ni
[e]
[oJ 3
[lc | al
(VIDEO-3)
EXT. SPK SW. S-VIDEO TERM.
EXT. SPK TERM. (MAIN) MONITOR OUT
EXT. SPK TERM. (SURROUND)
EXT. SPK TERM. (CENTRE)
AERIAL TERMINAL
VIDEO-3 (COMMON WITH FRONT TERM.)
21-PIN SOCKET 2 (S-VIDEO/AV)
21-PIN SOCKET 1 (FULL)

REMOTE HAND HELD UNIT
KEY ASSIGNMENT
ON/STAND-BY
. Sound mute
(Quick/advanced operation)
CALL (On-screen call)/ (index, initial) ........ TELETEXT MODE
>” een PICTURE MENU
p») ieiwes SOUND MENU
@ Mi... <TV MODE > = STEREO BILINGUAL
1~9,0... TEN KEY
-/ee ou 1 or 2 place
OS ee VIDEO INPUT (EXTERNAL INPUT SOURCE SW.)
Pa ener VOLUME
an ahdouts LEVEL PLUS (VOLUME, MENU)
oe ahve LEVEL MINUS (VOLUME, MENU)
) are UP (POSI., CH., TEXT PAGE)
WW enaa DOWN (POSI., CH., TEXT PAGE)
oO TXT/V....... TEXT, MIX, TV MODE SW.
Pea tee HOLD
O ree. | Qo <TEXT MODE > ....... REVEAL / CONCEAL
JIE") TEXT (ED eee < TEXT MODE > ....... F-T-B
C) (FULL, TOP, BOTTOM)
Lt
— © ~~ TEXT CLEAR (TEXT MODE)
FLOF COLOUR KEY (4 key used)
Red/Green/Yellow/Blue
OT esses Super woofer
Dud] ste Sound mode select
IIR cess Selectable picture
APR cee Selectable sound
MENU..... TUNING & OTHER MENU
@/@- Menu select
@/q@-: Level down/up
16:9... PIC SIZE (Picture size select)
VWaliHSoL
VTR control
(5 Power on/standby
> Play
H Stop
<<) Rewind
CT-9763 >> Fast forward

CIRCUIT BLOCK DIAGRAM
VY
TN-EG465LX1
MVGS44A
UR
TUNER IF/MPX
* *
*
AUDIO
@ [8s
oS TA1218N
BAe 3 : e
)
AvVSW.
LY
(FULL)
|9
§
P
avsw
[xe
TA1229N
° . re SECAM
2
COMB
-©)
jes
BRIER
TA1222AN
O° fe)
(2) |9 “4
21PIN |6 2 SAA5281ZP/E CHROMA
(S+AV)IE
0
RGB
VIDEO
oS
DEF.
©
RGB SW
iad
Cc El
ie
PROCESSOR ee |
Al
TA1217N
EXT SPK
*
PRO-LOGIC
UNIT
TA8211AH
TA8772AN +O ores}
1H | ieee: ‘ones ro] EXT SPK
DELAY “EXT/INT
HEAD PHONE SPK SW WOOFER
VIDEO OUT
12C
BUS
2804544
x3
©
TC74HC4053AP
ae
(FRONT)
p-CON
;
OSD
RGB
TA8427K
*
Ey
Ss
MEMORY
[_,]|
(3)
Vv
NM24CO04EN
TPM87CP38N-3228
TA8859AP
HV.
(REAR)
9
R
H.
OUT
+B VOLTAGE
2SD2253FA
F.B.T.
>
HYBRID
CONVERTER
TRANS.
STR-S6709
* PC BUS CONTROL

WARNING:
BEFORE
SERVICING
THIS
CHASSIS,
READ
THE
“X-RAY
RADIATION
PRECAUTION’,
“SAFETY
PRECAUTION”
AND
“PRODUCT
SAFETY
NOTICE”
ON
PAGE
2
OF
THIS
MANUAL.
INSTALLATION AND SERVICE ADJUSTMENTS
GENERAL INFORMATIONS
All adjustments are thoroughly checked and corrected
when the receiver leaves the factory. Therefore the
receiver should operate normally and produce proper
colour and B/W pictures upon installation. However,
several minor adjustments may be required
depending on the particular location in which the
receiver is operated.
This receiver is shipped completely in cardboard
carton. Carefully draw out the receiver from the carton
and remove all packing materials. Plug the power cord
into a convenient 220 volts 50 Hz AC two pin power
outlet. Turn the receiver ON. Check and adjust all the
customer controls such as BRIGHTNESS,
CONTRAST and COLOUR Controls to obtain natural
colour or B/W picture.
AUTOMATIC DEGAUSSING
A degaussing coil is mounted around the picture tube
so that external degaussing after moving the receiver
is normally unnecessary, providing the receiver is
properly degaussed upon installation. The degaussing
coil operates for about 1 second after the power to the
receiver is switched ON. If the set is moved or faced
in a different direction, the power switch must be
switched off at least 30 minutes in order that the
automatic degaussing circuit operates properly.
Should the chassis or parts of the cabinet become
magnetized to cause poor colour purity, use an
external degaussing coil. Slowly move the degaussing
coil around the faceplate of the picture tube, the sides
and front of the receiver and slowly withdraw the coil
to a distance of about 2 m before disconnecting it
from AC source.
HIGH VOLTAGE CHECK
CAUTION: There is no HIGH VOLTAGE ADJUST-
oe on this chassis.
. Connect an accurate high voltage meter to the
second anode of the picture tube.
2. Turn on the receiver. Set the BRIGHTNESS and
CONTRAST Controls to minimum (zero beam
current).
3. High voltage will be measured below 32.0 kV.
4. Rotate the BRIGHTNESS Control to both extremes
to be sure the high voltage does not exceed the
limit of 32.0 kV under any conditions.
FOCUS ADJUSTMENT
Adjust FOCUS Control on FLYBACK TRANS. (1461)
for well defined scanning lines in the centre area on
the screen.,

SERVICE MODE GENERAL INSTRUCTIONS
1. ENTERING TO SERVICE MODE
1) Press “XK button once on 2) Press «K button again to 3) Keep pressing the *X button,
Remote Control. keep pressing. press MENU button on TV set.
RCUT Ss
32H
—_—_—_—_—— RR al
(Service mode display)
2. DISPLAYING THE ADJUSTMENT MENU
Press MENU button on TV.
Adjustment mode Service mode
RCUT Item
32H
Data
Press
we — E288
3. SELECTING THE ADJUSTING ITEMS
Every pressing of CHANNEL 4 button changes the adjustment items in the following order. (¥ button for reverse
order.)
4. ADJUSTING THE DATA
Pressing of VOLUME 4 or W button will change the value of data in the range from 00 to FF. The variable range
depends on the adjusting item.
5. EXIT FROM SERVICE MODE
Press POWER button to turn off the TV once.

OTHER SERVICE FUNCTION
The following key entry during display of adjustment menu provides special functions.
Remote Controller
CALL/ E) CAUTION! CALL/
Never try to perform
ad initialization unless you COI CALL ATTY
have
changed
the
OO’
O
A
Position up memory IC. LI G2) (sy
button on | | il
the TV set a (4) (5) (6) Ga
+ an =
(8) ‘a Reset th
Initialization
of
the
MEMORY
(QA02)
x
O
.
au
Sieh
pay
of
operating
protect
5 NS
B cut off
G
cut
off
O
OQ
fe)
0
(BCUT)
(GCUT) O e) OO
R cut off <1 -/+ Data adjusting
(RCUT)
Contrast correction
(CNTX)
Color thickness
correction
note: Displayed differently as
shown below, depending
on the setting of the
receiving color system.
COLP (PAL)
COLC (NTSC)
COLS (SECAM)
Test sound signal
ON/OFF (1 kHz)
( In TEST SIGNAL SELECTION )
mode operating. See next page.
Tint correction
(TNTC)
Self diagnosis
Test signal selection
Horizontal line
ON/OFF
a
Oo
on
=
03
>
Reset the count of operating
protect circuit
(Refer to the above.)
initialization of the MEMORY
(Refer to the above.)
{@ code. | babel
Service adjusting mode
Ye \\\ —
Service normal mode
(In service mode, ordinary
operations are possible.)
Sialic mle The adjusting item selection
~ 8-—

TEST SIGNAL SELECTION
Every pressing of -@) button changes the test patterns on screen as described below in SERVICE MODE.
Signal off —> NTSC signals (14 patterns)
PAL signals (14 patterns)
* About inside signal: The inside signal is output at video input terminal from QA01, and is not output with the pin
inserted into terminal. (Single color signal can be output.)
Signals Using method
Purity and White uniformity of CRT
* Red single color Red single color. . . . Stopping G and B output of Q501
* Green single color Green single color. . . . Stopping R and B output of Q501
* Blue single color Blue single color. . . . Stopping R and G output of Q501
* Black single color Black single color. . . . Making black signal of approx. 1Vp-p in QA01
* White single color White single color. . . . Making white signal of approx. 1Vp-p in QA01
* W/B adjustment White balance adjustment
White part. . . . White balance adjustment/check in light area
Black part. . .. White balance adjustment/check in dark area
>< Making approx. 1Vp-p signal in QA01.
* Black cross-bar Picture position (horizontal, vertical and slant) in CRT adjustment
* White cross-bar >< Making approx. 1Vp-p signal in QA01.
* Black cross-hatch Convergence and vertical amplitude adjustment
* White cross-hatch 3X Making approx. 1Vp-p signal in QA01.
* Black cross-dot Convergence adjustment
* White cross-dot a 3X Making approx. 1Vp-p signal in QA01.
* H signal For checking (of purity drift) of white uniformity of CRT
(Left, right, white) H signal (Left, right, white). . . . Check in light area
° H signal H signal (Left, right, black). . . . Check in dark area
(Left, right, black) The adjustment will be the best, if the time when unevenness of color in light
area occurs, is a little longer than that in dark area.
%% Making approx. 1Vp-p signal in QA01.

SERVICE MODE ADJUSTMENT
ITEM ADJUSTMENT PROCEDURE
INITIALIZATION OF QA02 After replacing QA02, the following initialization is required.
(MEMORY) 1. Call up the adjustment mode display following the steps 1 and 2 on page 7.
2. Press the CALL button on the Remote Control and CHANNEL A buttons on
the TV set simultaneously. The initialization of QA02 has been completed.
3. Check the picture carefully. If necessary, adjust any adjustment item.
Perform “AUTOMATIC SEARCH MEMORY’.
. 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 4 -/+ button to reduce the
value so that white portion of inside
pattern slightly light.
4. Adjust .4 -/+ 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.
SUB-BRIGHTNESS
(Address : BRTC)
Note: Constrict the picture
height until the vertical
retrace line appears
adjusting the address HIT
(HEIGHT).
Belt of vertical retrace
HORIZONTAL POSITION
ADJUSTMENT (HPOS)
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 A, W
buttons, and adjust horizontal or
vertical picture position in the center
of screen with VOLUME .4 -/+
buttons.
VERTICAL POSITION
ADJUSTMENT (VPOS)
VERTICAL AMPLITUDE
ADJUSTMENT
(HIT)
1. Set the TV in service mode, and get
black or white cross-hatch signal with
VIDEO button on remote hand unit. The first ceHHH
2. Select HIT (Vertical amplitude) with Hoe
CHANNEL
A,
¥
buttons,
and
adjust
BERGE
vertical amplitude with VOLUME ZEEE
<1 —/+ buttons so that vertical
amplitude lacks a little.
3. Adjust vertical amplitude with VOLUME
<1 —/+ buttons so that the first bar on
cross-hatch signal touches edge of
screen.
~10-

ITEM ADJUSTMENT PROCEDURE
WHITE
BALANCE
1.
Set
Contrast
to
40,
and
brightness
to
+20
by
picture
control.
ADJUSTMENT
2.
Set
the
TV
in
service
mode,
and
get
the
inside
W/B
adjusting
signal
with
VIDEO
button
(see
pages
7,
9.).
3. Select RCUT, GCUT and BCUT with CHANNEL A, YW buttons, to set
individual
values
to
32,
and
to
set
GDRV
and
BDRV
to
20
with
VOLUME
<i —/+ 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 4A, W buttons.
Then tap VOLUME .4 -/+ buttons so that three colors slightly light in the
same level.
Light area check
(to show white)
* CUTOFF ADJUSTMENT
(RCUT)
(GCUT)
(BCUT)
* DRIVE ADJUSTMENT
(GDRV)
(BDRV)
XX To correct white balance in light area,
select GDRV and BDRV with CHANNEL
A, V buttons to adjust.
XX To correct white balance in dark area,
perform fine adjustment of RCUT, GCUT
and BCUT.
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.
® BLOCK
{SELF
CHECK)
UV
:
TV
reception
mode
@®
|
23905310
V1:
VIDEO
1
input
mode
(©)
1)
@
|
Power
:
00
V2
:
VIDEO
2
input
mode
(©
2)
@ | BUSLINE : OK
@®]
BUSCONT
:
OK
Indicated
color
of
mode
now
selected:
Green
and
Red
®
|
Block
>:
UVV1
V2
Indicated
color
of
other
modes
:
White
Qvo1
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 QVO1.
QV01 : In case of indication green ---Normal
In case of indication red with input signal----
@ Part number of microcomputer (QA01)
@® 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.
® BUS LINE CHECK ----“OK" is normal. Failure may exist in output line including QVO1.
“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.
@ BUS CONT ----“OK” is normal.
When indication shows “QOOO NG’, the device
with the number may possibly be damaged.
-i1-

ADJUSTMENT OF VIDEO-CHROMA SYSTEM (Factory adjustment)
Model Name: C5SS
Setting
:
Measure-
:
Adjustment
i Select slave address OCH |1.35V(p-p)
{[COLP] SUB Contrast: MAX Sub-bright
COLOR Bright : CENTER | signal [COLP].
. When [COLP] is selected, Y-
PAL Color : CENTER | (PAL)
signal is muted and only color
signals are outputted.
. Adjust amplitude of the upper
half of the color bar output.
. Set the controls as shown in
the left column.
2. Gradually increase the screen
VR (T7461) until one of R, G or
B line begins to brighten
slightly.
3. Determine the position of the
screen VR here.
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 -/-- button on the remote
control to escape from the
horizontal line mode.
. This adjustment must be done
after adjustment of the above-
mentioned cut-off and screen
VR’s have been completed.
2. Adjust cut-off and drive DATA
alternately.
3. Use a checker to adjust
brightness by changing
modulation factor.
{BELL}
BELL
SECAM
QQ01
#21
|Vary
[BELL]
so
that
waveform
|100+10%
filter
color
bar
(TPM01)
|
becomes
flat
on
scope.
[SRY]
SECAM
Dynamic
mode
|SECAM
Q501
#55
|Vary
[SRY]
so
that
level
of
B/W
]0+40mV
R-Y
color
bar
(TP501)
signal
part
matches
to
that
of
black
label
H.BLK
on
scope.
[SBY]
SECAM
Dynamic
mode
|SECAM
Q501
#55
|Vary
[SBY]
so
that
level
of
BAW
|0+40mV
R-Y
color
bar
(TP501)
signal
part
matches
to
that
of
black
label
H.BLK
on
scope.
[COLS]
Sub-color
|Dynamic
mode
|SECAM
Q501
#55
|
Adjust
amplitude
of
color
bar.
3.5
+
0.2V(p-p)
center
color
bar
(TP501)
(Set
the
video
mute
during
SECAM
adjustment.)
RCUT
GCUT | 40 Hexa-decimai
BCUT
GDRV ) 40 Hexa-decimal
BDRV
Select horizontal line mode by
pressing -/- - button on the remote
control in service mode.
adjustment
Screen VR
HIGH LIGHT;
(103cd/m3)
7195K
-0.005uv
DARK;
(17cd/m3)
7695K + 0uv
Screen
adjustment
Contrast: MAX White, etc.
Bright : CENTER
Color : CENTER
-12-

ADJUSTMENT PROCEDURE
Model name: C5SS (2857DD)
Adjustment parts or Input point/
Output point Adjustment signal Adjustment conditions and procedures
: 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
Color: Center
2. Adjustment procedure
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 HCP.
d. Again, adjust the sub address WID.
: Keystone distortion
compensation amount
adjustment (HCP)
43

SUB DATA ADDITIONAL DESCRIPTION
Description
H screen position correction.
Linearity balance between top and
bottom screen.
V linearity correction 2.
Linearity
Linearity balance between
top/bottom and center.
V picture position adjustment.
-14-

Setting of amount of V amplitude
correction against variation of screen
brightness.
H pin-cushion distortion correction.
H pin-cushion distortion correction at
four corners.
Setting of amount of H amplitude
correction against variation of screen
brightness.
V linearity correction.
Linearity balance at 1/4, 3/4 areas
from top.
Linearity
-15-

MULTI BUS E2PROM ADDRESS, ADJUSTING ADDRESS TABLE
QA02 Value of initializing
memory QA02
address i (Hexa-decimal)
Adjusting
method
R CUTOFF (B/W)
G CUTOFF (B/W)
B CUTOFF (B/W)
G DRIVE
B DRIVE
SUB CONTRAST MAX (4:3 MODE)
SUB BRIGHT CEN
SUB COLOR CEN NTSC
SUB TINT CEN
SUB COLOR CEN PAL
SUB COLOR CEN SECAM
SUB COLOR
SUB CONTRAST
VOL SCART
FM VOL PRE SCALE
NICAM VOL PRE SCALE
NICAM THRESHOLD LEVEL
NICAM THRESHOLD LEVEL
IGR THRESHOLD LEVEL
IGR THRESHOLD LEVEL
EXT PRE. VOLUME
NICAM ON LEVEL
NICAM OFF LEVEL
FM ATTENUATOR LEVEL
STEREO SEPARATION
50Hz H-POSITION
V-POSITION
HEIGHT
V-LINEARITY
V-S CORRECTION
V-SHIFT
V-COMPENSATION
PICTURE WIDTH
E-W PARABOLA
E-W CORNER
TRAPEZIUM
H-COMPENSATION
V-F CORRECTION
SECAM BELL FILTER
SECAM R-Y
SECAM B-Y
S ... semi-fixed data area which is fixed by model. (Do not adjust in field service.)
F ... This item may require adjustments by models after initialization, wnen QA02 is replaced.
-16-—-

EXTENSION CABLE SET
Extension Cable Set is available for servicing modules.
For
C5SS
chassis,
however,
this
cable
is
used
only
for
PRO-LOGIC,
TELETEXT/RGB
and
COMB
FILTER
modules. (See reference table on next page.)
Identify
number
of
pins
by
reading
surface-print
on
the
pc
board
of
cable
set.
23305270 Extension Cable Set
EJ
f-]
SE eS
Ww
y
)p Pp
BERBERS
Es a) |) eed
a es
= Ey
AN
A (6P)
(RED)
Note: identify number of pins
by reading surface-print on the
pc board of cable set.
(ex.) PB3438-1-15
H
(15P)
IC
15
pins
-~17-

TO USE THE CABLE SET
1. Unsolder corners on shielding case of module, SGEDER
which are marked with arrow in the figure.
at
2. Remove shielding case, and pull up module to
disconnect.
PULL UP
3. Connect Extension Cable Set to module and Main
board.
>
ee
v iy
Sa Y connect
aa
TO
MODULE
4. Reference chart of module and extension cable pin. i
:
PRO-LOGIC
TELETEXT/
RGB
SECAM/1H DELAY
COMB circuit can not be used
FILTER because of 11 pin
connector.

HOW TO MAKE THE CHASSIS STAND FOR REPAIR OF THE 2857DD
1. Disconnect the lead wires for the speaker fixed to
the degausser coil with three omega clips.
2. Lifting up slightly, pull out the chassis from the
front mask.
3. There is a slit at the left front of the bottom side of
the front mask. Lift up the left side of the chassis
and insert the hook at the right side into the slit.
-19-

4. To retain the chassis, use the upper left boss
(highest boss) which is marked with No. 29.
5. Fix it with screws for back cover fixing.
Upper hole of the chassis frame.
6. After repair works, restore the unit by reversing the
above steps.
-20-