Philips MDl .2E User manual

Colour
television Chassis
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Seruice
4.
5.
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Contents
Technical
speciÍications
Connection
facilitiesand Chassis
overview
SaÍetyinstructionsfor repairs,
Maintenance
instructions,
Wamings
andNotes
Mechanical
instructions
Blockdiagram
Testooint
overview
Wiringdiagram
Copyright
1996 PhilipsConsumerElectÍonics
B.V. Eindhoven,
The
Neitíerl-ands.
All rights reserved. No part of this Publication
may be
reoroduced,storedjna retrieval
systeni
ortransmitted,
inany
formorby
arivmeans,
electronic,
mechanicá|,
photocopying,
or otherwise
without
théprior
permission
ofPhilips.
published
by
SM
9671TVService
Department
PrintedinThe
Netherlands
oCopyright
reservedSubiect
tomodification
Contents
Electrical diagrams and PWB-layouts
(Schéma
BB)
(Schéma
84)
(Schéma
85)
(Schéma
86)
(Schéma
87)
(Schema
BB)
(Schéma
89)
(Schema
C)
(Schéma
01)
(Schéma
D2)
(SchémÊ
D
(Schema
G)
(Schéma
l)
(Schéma
J)
l"g"
Diagram PWB
21 18
21 18
22 18
22 18
23 18
@ 4822727 20979
MDl
.2E
AA
í;ïiri?,'
Synchronisation
lFsound
EuroconnectoÍ
1
Euroconneetor
2
Controls
Connections
audio
module
Teletext
CRT
panel
Audio
module
NicamL module
CTI/Black
Stretch
panel
N/Soanel
Mains/RCS/LED
Panel
Control
andInpuvoutput
8. Electrical
alignments
10.Directions
Íoruse
11.ListoÍabbreviations
12. Spareparts
lists
t.
2.
3.
Page
2
2
3
4
6
7
8
8
Diagram PWB
12
13 14
15 14
16 14
17 14
17 14
19 18
20 18
6. Service
Modes,
DST,Errormessages,
Protections,
Faultfinding
and Repair
tips
7. Electrical diagrams and PWB-layouts
Supply
voltagediagram
Power
supply21" (Schéma
A1)
Powersupply
>21
" (Schéma
A1)
Horizontal
output (Schéma
A2)
Vertical
output (SchémaA3)
AudioampliÍier (Schéma
Aa)
Tuner+ lF (Schéma
81)
Videoprocessing (Schéma
82)
24 18
24 18
25 25
26 27
27 27
28 29
29 29
30 30
31 31
32
34
37
39
PCS
82264GB
#p PHILIPS

1. Technical speciÍications
Mains
voltage
Powerconsumption
nominal
output
power
(Vvatt)
peak
output
power
Watt)
standby
Watt)
Mainsfrequency
Pull-in
rangecoloursynchronisation
Pull-inrange
horizontal
synchronisation
| 22O-24OVAC (!1O"A)
: 100
(21'90");
130
(1
10"SF
4:3);
150
(1
10"
SF16:9)
: 160
(21"
90");
180
(1
10'SF4:3);220
(1
10'
$F 16:9)
: 3 (t10%)
: 50Hz
(t10%)
: >+300H2
: > +600H2
#
\? ?o
(
r1----------------a
o OqEo
(DGREEN
tÍ
r--------------'
t ?ooYt
--T-l-- oo
SK1
/+\
L7-\l
\ \:iï- MENU
:Íffi'-''" \:.2-
m-"-.
ileït-- "*"
ilq|- *-"
l[o+]- -*'
l#n
lo
|
*ï--'
lo+-
g-".-
*rH*
1-
2-
3-
4-
5-
6-
7-
8-
9-
10-
11
-
12-
13-
14-
15-
16- EXT1/75o)
17 - CVBS I
18 - CVBS J-
19- CVBSo(1Vpp/75O)
20- cvBS€(1vpp/75o)
21 - Earth screen
Audio O R(O.SVnrvrs< lko)
Audio € R(0.2-2Vnus>
10ko)
Audio G L(0.SVnrr,rs<
1kO)
Audio I
Blue I
Audio€ L(0.2-2Vnurs>
loka)
Blue o (0,n/pp/75o)
CVBS
status(o-2V:
INT;
4,5-7Vl
EXT1
-1
6/9;9.5-12V:EXT1
-4l3)
GreenI
GreenO (o,7vpp/75o)
Red I
RGBstatus
I
Red o (0,7vpp/75o)
RGBstatus
(0-0,4V:
INT;1-3V:
SVHS
@
2. Connection
facilities
andChassis
overview
Rearconnectlons
Specification
oftheterminal sockets
REAR
EXTI- CVBS
(in/cut)
+
RGB
(in)
-
tuner
atoutput
Front+Topcontrol
+Side l/O
EXT2 -CVBS
(in/out)
+
SVHS
(in)
-Input:
EXTz
then
output
=
tuneriinput:
other
then
outPut
=inPut
1 - Audio
OR(o.SVnrus<lk())
2 - AudioO R(0.2-2Vnr'irs>10ko)
3 - Audio
GL(o.SVnus<1ko)
4 - Audio I
5-
6 - Audio€ L(0.2-2Vnr'rs>10ko)
7-
8 - CVBS
status€ (G2V:
INT;4,s7V:
EXï2-
1
6/9
;
9.5-
1
2Y
:F-Kï2=a
|
3\
9-
'10
-
11
-
12-
13-
C
I
14-
15- c o(300mvppl75à')
16-
17 - CVBS I
18 - CVBS I
19- CVBS0(1vpp/75o)
20 - cvBslío (1vppi75o)
21 - Earthscreen
Front + Side control + Side l/O
Cinch
-audio
out
O ctucx AudioL(red)
I
(0.5Vnr',ls
<1kA)
O ctNcH
AudioR(whire) O
(0.5Vnus
<1kA)
FRONT
Audiofuideo
in
O crncn cvBSO (1vpp/75o)
O ctrucn
Audio
L(red) O
(2Vnr',rs
>10kO)
O ctttcHAudioR(white)
O
(2Vaus
>1OkO)
Headphone
I qn 8-600ei
1-r
2-I
3 Yo (1vppnso)
4 - co(o,3vpp/75o)
PCS82265GB

EE-i] TopcontmlPanetd#
EE3il Side
Controldild/oÍ InpuUOutput
E P28| cTu8reksrÍerchPanel
ElP.r6 I AudioModure
Wp.n1 Ni€mLPanet
CRTPanel E p.zul
E Pirl
E-p.ro l
EEI
EEf-l
E-r,,t
E-p.tl
EEzg]
E p.zcl
E-t 4l
Tuner
/ lF
Vids PÍocessing
Synórcnislion
lFSound
Euro ConnecloÍ 1
EuÍoConnsdoí2
ContÍols
Connections
AudioModule
Teleteí
, SideConlÍolor Top ContÍol presenl
1.
2.
.Z- y#"jt^csrueo
I nso-]
<9
PoweÍsupply Eilp.13Jd
HoÍizonlatoutput
E P.16-l
VerlicalOutput E P.1il
AudioAmpliÍier E P.t7l
N/SPanet EE r-l
66532068_001.41
Note:
This resoldering
isadvised to prevent
badconnections
dueto
metalÍatiguein solder
jointsand isthereÍoreonlynecessary
Íortelevisionsetsolderthan2 years.
- Thewiretreesand EHTcableshouldbe routedcorrectly
andÍixedwiththe mountedcableclamps.
- The insulationoÍthe mainsleadshould
bechecked
lor
external
damage.
- The mainsleadstrainrelieÍ
shouldbechecked
for its
tunctioninorder
to avoidtouchingthe GRT,hot
components
or heatsinks.
- The electricalDC resistance
betweenthe mainsplugand
thesecondary
sideshouldbechecked
(only
for sets
whichhavea mainsisolated
powersupply).
Thischeckcanbe doneasÍollows:
o unplug
the mainscord andconnect a wirebetween
thetwo
pins
oÍthemains
plug;
e setthe mains
switchto the on position(keep
the
mainscordunplugged
!);
. measuÍe
the resistance valuebetween
the pinsoÍthe
mainsplugandthe metalshielding
oÍthe tuneroÍ the
aerialconnectionon the set.Thereadingshouldbe
between
4.5MOand12MO;
o switchofftheTV and removethe wirebetween
the
twopins oÍthemains
plug.
- Thecabinet
shouldbecheckedÍor defects
to avoid
touching
oÍ any innerpaÍtsby the customer.
3. Safety
instructions
Íorrepairs,Maintenance
instructions,
Warnings
and
Notes
SaÍety
instructionsÍor repairs
SafetyregulationsrequiÍethatduringarepair:
- thesetshould
beconnected
tothe
mainsvia
anisolating
transformer:
- saÍetycomponents,indicatedby
thesymbol
a
shouldbereplaced
by
components
identicaltothe
originalones;
- when
replacing
theCRT,safety
goggles
mustbeworn.
Safety
regulationsrequire
thatafteraÍepairthe setmust
beÍeturnedin
'rts
originalcondition.
In
particular
attention
shouldbe
paid
totheÍollowing
points:
- Asastrict
precaution,
weadvise
you
toresolderthe
solder
joints
throughwhichthe
horizontal
deÍlection
current
isflowing,
inparticulaÍ:
o all pins
oÍthelineoutputtransformer
(LOT);
o fly-backcapacitor(s);
. S-@rrectioncapacitor(s);
o line
outputtransistor;
. pins
ofthe
connector
with
wirestothe
deÍlectioncoil;
o othercomponentsthrough
whichthe
deÍlection
currentÍlows.

Maintenanceinstructions
Itisrecommendedto have a maintenanceinspection
carriedoutbya qualiÍied seÍviceemployee.
Theinterval
dependsontheusageconditions:
r whenthesetisusedunder
normal
circumstances,
Íor
example
ina livingroom,therecommended
intervalis3 to 5 years;
r whenthesetisusedincircurnstanceswithhigher
dust,
grease
ormoisture
levels,
forexanrple ina
kitchen,the recommendedinterval is 1year.
ThemaintenanceinspectioncontainstheÍollowing
actions:
. executetheabovementioned
"general
repair
instruction";
. cleanthepower
supply
and
deflectioncircuitry
on
thechassis;
. clean
thepicture tube
panel
andtheneck
oÍ
the
pictuÍe
tube.
Warnings
1. Inorderto prevent damageto lcs andtransistors,all
high-voltageflashoversmustbeave,ided. Inorder1o
prevent
damage
to the picture tube,the method
shon'n
in
Fig.3.1
should
beusedtodischargethepicture tube.
Usea high-voltage
probe
anda multimeter
(position
DC-V)
Discharge
until
the meteÍreadingis0V (afierapprox.30s).
l
ESD IÈs.
All lCs and nrarry othersemiconductorsare sensitiveto
electrostaticdischarges
(ESD).
Carelesshandlingduring
repair
candrasticallyshortentheliÍe.Makesurethatduring
repair
you areconnectedbya pulsebandwithresistance
to
the samepotential
asthe earthotthe unit.
Keepcomponents
and
tools
also
atthis
same
potential
Togetherwiththe deÍlectionunitancjany multipoie unil,
theflat squarepicture
tubesused
forrnan integratedunit.
ThedeÍlectionandthemultipoleunits
aíesetopiimally
ai
theÍactory.Adiustmeni ofthisunitduringrepair
isthereÍore
notrecommended.
Be
careful
when
taking
measurementsin
thehigh-voltage
sectionandonthepicture tube.
Neverreplace
mocjulesorotheÍcomponents
whiletheunit
isswitchedon.
Whenmaking
settings,
useplastic ratheÍthanmetaltools.
Thiswillprevent
any short circuiisandtireciangei
oÍ a
circuitbecomingunstable.
The diÍectvoltagesand oscillogramsshould
bemeasured
withregardto thetuner earth(J), or hotearth(I{) astnis
iscalled.
The directvoltagesandoscillograms showninthe
diagrams
shouldbemeasuredintheService DeÍault
Mode (see chapter8) witha colourbarsignal
andstereo
sound(L:3kHz,R:1kHzunless
stated
otherwise)
and
picture
carrierat 475.25 MHz.
WheÍe necessary,the oscillograms anddirectvoltages
are
measuredwith (''ll-)
andwithoutaerialsignal([).
Voltagesinthe powersupplysection aremeasured
bothÍor
normaloperation
(@)
and instandby(O). Thesevalues are
indicated
by means of the appropriatesymbols.
The picture tube PWBhasprinted
sparkgaps.Each spark
gap isconnectedbetweenanelectrodeoÍthe picture
tube
andtheAquadagcoating.
The semiconductors indicatedinthe circuit
diagramandin
the partslistsarecompletely
interchangeable
per
position
withthe semiconductors
intheunit,inespective
oÍ
thetype
indication
onthesesemiconductors.
Figure
3.1
DCtpoLBY
sunnounol
PRO
o
LOGIC
ManuÍactured
underlicensefrom DolbvLaboratories
l-icensing
Corporation.
DOLB'/,
thedouble-Dsymbol
D! andPRO
LOGICare
trademarksoÍ DolbyLaboratories LicensingCorporation.
Notes
1.
2.
3.
4.
5.
2.
3.
6.
4.
5.
6.
PCS
82266GB

4. Mechanical
instructions
The
MD1.2E
chassishas
two
different
mechanical
executions.
Styling
withtopcontroland
side
inpuVoutput
(also
applicableÍor MD1.1E
Widescreen)
Removing the Íear cover
1. First
allscrewsonthe rearcoverhaveto be removed.
. 4 Screwsarelocated
ateachcornerof the cabinet.
. 2 Screws
arelocated
atthe leftand rightbottom
cornersoÍthe rearcover.
. 4 ScrewsareÍixedatthe4 corners
oÍthe l/O panel
withthe Euroconnectors
andaerialinput.
2. The rearcoverisnow heldin position
by6 clicks
between
the cabinetandthe rearcover.Thereare
2 clicks
at the left,2 at the right
and 2 at thetop.After
loosening
allclicks(byreleasing
themwitha screw-
driver),
the rearcovercan be removed.
3. The coverplate
onthe l/O panel
withthe Euro-
connectoÍs
andaerialinputcanbe removedinthe
following
way:remove
thescrewinthe middle,release
theclickconnection
at the bottom
and lift
the cover
plate.
Processposition
Theprocess positionprovides
easier
access
to theentire
chassis.
1. Release
the mainscordÍrom itsÍixationbrackets.
2. Pushbackthe clicksbetween
bottom
plateandrear
coverand pull
thecabinet
atthe sametime backwards.
For some service positions cablesmay have to be removed
from their cable clamps and channets.
AÍterwards, put the cables back in their original position.
Click
(1)
Service
positions
Small
SignalPanel
(SSP)
componentside (Figure
4.1)
1. Push
downthe clicksoÍ the SSPbracket(1)andshift
the SSPto the lefi.
2. Pullupthe SSPand tiltthe SSPcounter
clockwise
to a
horizontal
position(180'with Large
Signal
Panel
(LsP)).
3. Putthe SSPinthe clicks(2)marked
"Sewice"
onthe
bottom
plate.
Whenallcablesonthe SSParedisconnected,
theSSPcan
alsobe removedfrom itsbracket(Figure4.2),providing
betteraccessto component
andcopperside.
bracket
_014.41
071096
4.1
PCS
82267GB
Figure4.1

LSP component side (Figure4.3)
1. Putthe SSP inthe horizontal
service
position
as
described
above.
2. Removescrew (3)fromthe LOTbracket.
3. Removethe bracket
byreleasing
click(4)andpulling
the
bracketupwards.
4. Release
clicks(5)and (6).
5. Liftthe LSP PWBoutof itsbracket
(indicated
bythe
arrow)and pull it a little
back.
Warning! The heat sinksarc not connected to ground.
LSP copper side x/ith table/workbencá (Figure 4.4)
1. Disconnectthe cableto the degaussing
coil(yellow
connectorL02on LSP).
2. lÍ necessary,
disconnect
the cable
on the leftloudspeaker.
3. Liftthe LSPÍrom its bracket
asdescribed
above (LSp
component
side).
4. Turnthe LSPundemeath
the CRTpanel(keep
cable
515/L15
UNDER
the
audiomodule)
asindicated
bythe
arrow (7).
The LSP now restsonthe bottom
plate,heldinplacebythe
cableclampon the heatsinkandthe LOT bracket.
Warning! Be careful not to damage the CRT-panel or
picture tube neck.
The heat sinksare not connected to ground.
SSP and LSP copper si]dewithout tabte/workbench
(Figure 4.5)
For this seruice positionMDl cable extensionkit
(service code number 4822 320 11695)is required.
1. Breakthe servicepin (marked
M't - see Figure4.3)from
itsposition
at the right handsideoÍ the bottom
ptate.
2. Disconneqt
the cableto the degaussing
coil(yellow
connectorL02on LSP)
andthecableonthe left
loudspeaker.
3. Remove cables
510/L10,
511/L11and51
5/L15Írom
LSPto SSPand cablel28lL28
ÍromAudiomodule
to LSp.
4. Liftthe LSPlrom itsbracketasdescribed
earlier(LSP
component
side).
5. Putthe LSP to thevertical
position
(Figure
4.5),copper
sideatthe righthand,LOTabove(8).Forthisposition,
specialgroovesare madeinthe bottomplate
ofthe
cabinet.
6. Fixthe position
oÍthe LSPby putting
theservice
pin
betweenLSP (heat
sink)and bottom
ptate(9).
Thereare
specialholesinthe heatsinkandthe bottom
plate
to put
the servicepin in.
7. Reconnectcable
128/128.
8. Usethe cablesÍromthe MD1cableextension
kitto
reconnect
connectors
S10/L10, S1 1
/L1
1and51
S/LiS.
Warning! All cables should be reconnected correctly.
Afterusethe servicepincanbe placedinthe spareholeat
the righthandside inthe bottom plate.
Clip(6)
Click
(4)
Figure4.3
Figure4.4
c166532052_015.Al
110996
665320s2017.41
Figure4.5

Mechanical
instructions
4.2
Accessingthemodulewithmainsswitch,
LED
and
RC5
receiver
(Fig.4.6)
1. Cut
thetierap
ofthedegaussing
coilatthelefthand
bottomside
(10).
Removethe
degaussingcoilintheleft
bottomcorner
Írom
its
Íixationbracket
(1
1)
toget more
spacetohandlethemains
module.
2. Remove the
redmains
pànel
bracketby
lifting
theend
and
pulling
itbackwards
(12).
3. Toget
more
movement
space,the
lefttopofthecabinet
can
be
pushed
orpulled upwards
(13).
4. Themains
panel
cannowbe
removed.
Afterwards
the
degaussingcoilshould
be
retiedatposition
(10).
Styling with side control and side inpuVoutput (notop
control)
Removing
ttrerear
cover
1. First allscrewsonthe
rear
cover
have
toberemoved.
. 6Screwsarelocatedatthe
comersoÍthecabinet.
. 2Screws
aÍe
locatedatthe
leftand
right
bottomoÍ
therearcover.
. 3Screws
arelocated
just
above,
underandleftoÍthe
cover
plate
ofthe
UO
connections.
Fotsomeservice
positions
cables
may
havetoberemoved
íromtheircableclampsandchannels.
Aftenttards,
putthe
cablesback
intheiroriginal
position.
Process position
The
processpositionprovides
easier
accesstotheentire
chassis
duringthe
service
posltions.
1. Thechassis canbe
lifted,
pulled
Íorward
(t Scm)and
fixedinthebottom
plate.
2. Whentheclicks
between
bottom
plate
rearcoverare
pushed
back,thechassisand
thebottom
plate
canbe
pulled
backwards.
Service
positions
SSPcopperandcomponentside,
moduleservicing
(Figure
4.7)
'1
. Releasethe
clickconstruction
(14)
betweentheSSPand
LSP.
2. LifttheSSPalittleandturn
ittoanangleoÍ135'
(15)
or
180"
(16)
ÍromtheLSP.
This
provides
betteraccess
tothe
clmponent
sideoÍthe
SSPandalsoallows
fortheremoval
oÍmodules.
Service
position
withtable/workbench
(Fig.
4.8)
1. Disconnectthecable
tothe
degaussing
coil
(yellow
connectorL02onthe
LSP).
2. Lifi the
chassis
from
thebottom
plate
and
pull
it
backwards
(17).
3. TurntheentirechassisaroundtheCRT
panel(18).
The
chassisrests
on
theSSP
withthe
coppersideof
the
LSPbackwards.
Becareful
nottodamage theCRT-panel
or
picture
tube
neck.
Theheatsinks
arenotconnectedtoground.
(10)
(1
1)
(12)
66532052_018.Al
071096
Figure4.6
Figure
4.7
66532052_019.Al
250996
(14)
Warnlng!
FiguÍe4.8

Service position (LSPcopper side) without table/
workbench(Fig.4.9)
1. Disconnect thecable tothedegaussing coil
(yellow
connector
L02onthe LSP).
2. Liftthe chassis
Íromthe bottom
plateandturn it
counter
clockwise
(1
9).
3. The SSP can beÍixedwitha screwdriver tothe bottom
plate(20).
The coppersideofthe LSPcan nowbe
accessed.
Waming! Be careful notto damage the CRT-panelor
picture tube neck.
The heat sinksare not cannected to ground.
SmallSignalPanel
(Fig.4.2)
First,remove
allcablesconnected to the SmallSignal
Panel.The SSPcan be removed
byslidingitoutofthe
SSPbracket
(in
the direction ofthe arrow).
LargeSignalPanel
(Fig.4.10)
After removingthe screw(21), andpushing backthe clips
(22),
the LSPcan be liftedoutthe bracketas indicatedby
thearrow.
Accessing the panel with mains switch, LEDand RCS
ÍeceiveÍ
The mainsmoduleislocated inthe middleoÍthe set.below
thepicture tube.
1. Pushthe clicksbetweenbottom
plateand rearcover
backand pullthe chassisbackasÍar as possible.
2. ReleasetheclickconstÍuction
(14
- Fig.4.7)
between
the SSP and LSP,liftthe SSPa littleandturn itto an
angleoÍ 180' (16
-see
Fig.4.7)lromthe LSP.
Themainspanelcannowbe accessedwhenreaching
over
the SSP/LSP.
3. Remove the 2 screwsleftand rightonthe mains
panel
bracket.
Thecompletemains
panelcannowbe removedby
pulling
itbackwards.
Figure4.9
cffi262 02.A1
-i1ffi
Figure4.10
PCS
82268
cB

I
PANEL
5.B|ockdiagram/B|ockscha|tbi|d/Schéma.bloc@r
7l
I
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Ubersicht
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points
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Íorts
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Testpoint
overview
/Testpunkt
Ubersicht
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des
points
de
test
CRT
panel/
CRT-Platine
/ Platinetube
cathodique
CTUBlaek
Stretch
panel
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12111098 7 6 5 4 3 2 1
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Wiring
diagram
/Verdrahtungsschema
/
Schéma
de
càblage
SIDEI/O SIDE
/TOP
CONTROL
@r
U)
l
O
lL
CRT.
riiiSl v
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cL 66532052_001.41
190996

6. Service
Modes,
DST,Error
messages,
Protections,
FaultfindingandRepairtips
Inthischapter
thefollowingparagraphs are included:
6.1 Test points
6.2 ServiceModesand DealerService
Tool (DST)
6.3 Error
codes
and
"blinking
LED"
procedure
6.4 Protections
6.5 Fault
finding
andrepair tips
6.1 Test
points
The MD1chassis
isequipped withtest pointsinthe service
printing.
Thesetest points arereÍerringto the functional
blocks:
* A1-42-43, etc.: Test points
for the audioprocessing
circuitry
* C1-C2-C3,
etc.: Test
points
for
thecontrolcircuitry
* F1-F2-F3,etc.: Test
points
fortheframedriveand
frameoutputcircuitry
* L1-L2-L3,etc.: Test ooints
Íor the linedriveand line
outputcircuitry
* P1-P2-P3,etc.: Test
points
forthepower supply
* T1-T2-T3,etc.: Test
point
fortheteletelccircuitry
* V'l-V2-V3,etc.: Test
points
Íor
the
video
processing
circuitry
6.2 Service
modes
andDealerService
Tool
(DST)
Foreasyinstallation
anddiagnosis
the dealerremote control
RC7150
isintroduced.The RC7150canbeused forall new
TVsets, including
allsetof
theMD1chassis.TheRC7150is
alsocalled DealerServiceToolor DST.The ordering
numberofthe DST (RC7150) is 4€,2221821232.
6.2.1 Installation Íeatures Íor the dealer
Thedealer
canusetheRC7150for
programming
the
Tv-set
with
presets,
Tv-settings,
Dish
settings.
10
Differenl
program
tablescanbe
programmed
intotheDST
viaaGFLor
MD2TV-set
(downloading
fromthe
GFL
orMD2
to
the
DST;seeGFLorMD2servicemanuals)orbythe
DST-I
(DST/PC
interf
ace;orderin
g code4822
21
82127
n.
For
explanation
oftheinstallation
Íeatures
ofthe
DST,the
directions
foruseofthe DST
are
recommended
(For
theMD1
chassis,downloadcode4shouldbeused).
6.2.2 Diagnose features for the servicer
TheMD'|
.2
setscanbe
put
inthetwoservicemodes
viathe
DSTRC7150.
These
aretheServiceAlignment
Mode
(SAM)
andtheService
Default
Mode
(SDM).
SDM
canalso
be
enteredby
shortcircuitingthe
"seÍvice".pins
ontheSSP.
6.2.2.1Service
DefauftMode
(SDM)
EnteringtheSDM:
- Bytransmittingthe "DEFAULT'command
withthe
RC7150
Dealer
Service
Tool.
- Bytemporarily
shorting
pins
S42andS43ontheSmall
Signal
Panel.
ExitingtheSDM:
- Switch
thesetto stand-by
(theerrorbuffer
isalso
cleared).
Note: When the mains power is switched off while
the setis in SDM, the set will enter to SDM
immediately when the mains is switched on
again'
TheSDMhasthe Íollowing
pre-deÍined
conditions
Íor all
microprocessorcontrolled
tuningand linearfunctions:
- Forrecognitionofthe SDM "SER"isdisplayedatthetop
oÍthe screen.
- Tuningat 475.25MHz(Secam
on Multi-Francesets(with
NicamL),PALonothersets).
- Volumelevelissetto 25olo
(oÍthe maximum
volume
level).
Otherpicture
andsoundsettingsaresetto 5096.
- Autoswitchoffdisabled
(normally
the setisautomatically
switchedoffwhennovideosignal(IDENT)
was received
for15minutes).
- Sleep
timerisdisabled.
- Allothercontrols
operate
normally.
- Whenthe microprocessor supports the "blinkingLED"
procedure (See 6.3) and an error code is present in the
error buífer, the LED will blink the number of times, equai
to the value of the lasterror code.
This function will also work when there is no soud
or plcture.
6.2.2.2 SeruiceAlignment Mode (SAM)
Entering
SAM:
- Bytransmitting
the"ALIGN' commandwiththe RC7150
DealerService
Tool (this worksbothwhilethe set isin
normaloperation
modeorin theSDM).
- By
pressing
the"MENU" and':" key on
thelocal
keyboardsimultaneously
whentheset
isinSDM.
ÊxitingSAM:
- Switchthe setto stand-bv.
Note: When themains power is switched off while
Íhe sef is in SAM, the set will entet SDM
immediately when the mains is switched on
again.
lnthe SAMthefollowing
informationisdisplayedonthe
screen:
- Software
version(thesoftware
versionoÍthe
microprocessor
intheset isdisplayed.Thissoftware
versionidentiÍication
corresponds
withthe software
versionsinthe SoftwareSurveyas published
inthe
ProductSurvey.
- Errorcodebuffer(seeparagraph
6.3).
- Options
(seeparagÍaph
8.4).
- Alignmentand geometry
information
(see
paragraph
8.2.1,8.3.1
and8.3.2).

ServiceModes,
DST,Error
messages,
SoÍtwareversion
Error
buffer
Options
Alignments
and
geometry
Figure
6.1 Screen
oÍtheService
Alignment
Mode
(SAM)
Error
codes
and
"blinking
LED"
procedure
Ïhe errorcode
buÍÍer
containsallerrorsdetected
sincethe
last
time
thebuffer
was
erased.
The
bufferiswrittenÍrom
left
toright.
- Thelast
errordetected
(actual)
istheerroratthe
leftside
- The
errorbufferwill
be
resetintheÍollowing
cases:
1. exiting
the
SAMwiththe
"standby"
command
onthe
remote
control
2. transmitting
the
commands
"DIAGNOSE
99OK with
theDST
- Byleaving
theSAMwith
the
mains
switch,
theerror
bufferisnotreset.
Examples:
ERROR: 000000: Noerrorcodedetected
ERROR: 300000: Error
code3 isthelast
and
onlydetectederror
ERROR: 530000: ErrorcodeSfirstanderror
code5last detected
The
contents
ofthe
erÍorbufier
canalsobemadevisible
throughthe
"blinking
LED:
procedure.
Thisis
especially
usefulwhen
thereis
no
picture.
There
are
two
methods:
1. When
theSDMis
entered,
the
LEDwill
blinkthenumber
oÍtimes,
equaltothevalueoÍ
the
/asÍerror
code.
The
LEDwill
stay
offbrieflyandblinkagainthe
number
oÍ
times,
equal
tothevaluetothe/ast
errorcode
2. WiththeDST
a//error
codes
in
theerrorbuffer
canbe
madevisible.
WhileinSDM.transmitthe
command:
"DIAGNOSEx
Ol( wherexisthe
position
inthe
error
buffer
tobemadevisible
x rangesÍrom1,
(the
last
(actual)
error)to7 (the Íirst
error)
The LEDwilloperateinthe samewayas inpoint1,but
nowÍor the error
codeon position
x.
(1)
(21
(3)
(4)
Example:
Errorcodeposition 1 2 3 4 5 6 7
Errorbuffer 2 4 1 0 0 0 0
c afterenteing SDM
blink(2x)-pause- blink(2x)
. aftertransmlfÍ,íng
"DIAGNOSE
2 OK withthe DST
blink(4x)-pause- blink (4x)
o aftertransmrftlng
"DIAGNOSE
3 OK' with the DST
blink-pause-blink
. after transmltÍrÍng
"DIAGNOSE
4 OK' withthe DST
nothinghappens
Note!
lmportant!
Notethat it may take up to 7 secondsbefore
the setrespons to a DIAGNOSEcontmand.
lnterruption of the blinking sequence may
lead to incorrect results.
Not
allsoftwareversions
of theMDl.2E
chassissupport the blínking LED procedure
and the DIAGNOSE99 command. Software
versions NOTsupporting theblinking LED
procedure are MlZBAx-x.x and Ml2COx-3.x.
Table
6.1 Error
codelist
6.3
Enor
code EÍor desoiption Bfinking l€D, Pgssble , .
deÍectve-
coÍnpgnents:
0Noerror detected
BIMOS
(ID48366) error 1x 1c7119
(SSP)
2MSP3400/3410
erÍor 2x 1c7353 (ssP)
3lzc buserror 3x All lzC-related
components
4WrongEEPROM 4x rc7685 (SSP)
5EEPROM
defective 5x 1c7685
(SSP)
bTunererrol 6x u1000
(ssP)
7TXT
error 7x rc7702 (ssP)
8HistogramProc.
eÍror 8x 1c7210
(Íeserved)
916:9
processor
error 9x 1c7440 (16x9
module)
10 WSSBmodule
error 10x tc7540 (WSSB
module)
11 Dolby
processor
erÍor 11x rc7600 (Audio
module)

Protections,
FaultÍinding
and
Repair
tips
6.4 Protections
6.4.1 In theMD1.2E
the
Íollowing
protections
are
possible:
Protections
generated
by
the
power
supply:
o Overloadprotection
o Undedoad
o Overvoltage
. Undervoltage
DeÍlection:
o Horizontal
Protection
o EW-Protection
r VerticalProtection
Soítware
protection
o BIMOS
lC7119
deÍective -+ (ErroÍ
code1)
Setcan be switchedbetween
standby
andON,but
thereisnopicture,
noOSD,
soundisonly noise.
. SDAor SCL shorted -+ (Error
code3)
Setis
switched
tostandbyvia
standbyline,
set
tries
to
restart.
o No+SDb
or+8Sc
atgC -+ Set
is
switchedto
standbyvia
standby
line,
settriestorestart.
6.4.2 Power supply protections
The
power
supplywill
go
toavery
good
audiblehick-up
mode
in
the
following
situations:
r Overload
protection
r Underload
o Overvoltage
o Undervoltage
lnhick-up
mode
Pin1of1C7520
startsup
from
the
startcircuitÍor
approximately
2seconds,immediately
afterthatthe
protection
isastivated.
This
cycleisconstantly
repeatedin
hick-up
mode.
Whenthe
setisinhick-up
mode
ashort
squeakis
audible
every2seconds.
6.4.3 Horizontahprotection
When
thebeam
current
becomestoo
highÍoralong
period
thevoltage
across
C2450will
drop.D&50 will
staÍt
conducting
andassoon
asthevoltage
dropacrossR34S6
is0V7,
TS7450
will
conduct,makingPROT
high.
Via
thehold-circuitry
of
the
power
supply,the,setwillstay
in
the
protection
mode
(standby)
and
canonlyberesetby
switching
theset
offand
on
via
themains
switch.lÍtheÍault
is
still
present,
thesetwill
switch
tostandby
(protection
mode)
again.
6.4.4 Ew-protectaon (not Íor 21" sets)
The
EasVWest
protection
switchesthe
power
supply
to
standby
viathe
signalline
STANDBY-SUPPLY
PROTECTION.
Via
thehold-circuitry
ofthe
power
suppty,
the
setwillstayin
the
protection
mode
(standby)
andcan
only
bereset
byswitchingthe
set
oÍfandonviathemains
switch.lftheÍaultis
still
present,
the
set
will
switchto
standby
(protection
mode)
again.
--+ Hickupmode
+ Hickupmode
+ Hickupmode
-+ Hick
upmode
-+ Supply
to standby
-+ Supply
to standby
-+ BIMOS
standby
mode
6.4.5
6.4.6
The
EasVWest
protection
detectswhen
thecurrent
through
theEasvwest
power
output
stage
with
TS7480
istoo
high.
Note: A cunent
throughtheEaswest stage
that
istoohigh
canbecausedbyadefective
partintheline-deflectíon
circuitrv!
Thecurrentthrough
the
EastArVest
stageismeasured
on
theLSPvia
2precision resistors(R3483
and
R3484).
In
caseoÍaline
problem,
the
easvwesÈcurrent
becomes
toohigh
andthevoltage
acrossresistors
R3483
and
R3484
rises.
When
the
voltagelevel
exceeds
0.6V,D6480
stans
toconductand
STANDBY-SUPPLY
PROTECTION
becomesHIGH.
Whenthevoltage
across
C2480
isvery
high
(e.9.
when
aline
problem
ís
already
present
when
the
setis
switched
onwiththemains
switch),D6zl81
andD6,f82
conduct
andEW-PROTECTION
isactivatedvery
Íast.
The
East/West
protection
becomes
activeinthe
Íollowing
cases:
1. Badcontacts
oÍhorizontal
deÍlection
circuit:
. badcontacts
ofhorizontal
deflection
coil
r badcontacts
oÍlinearity
corrector
coilL542i
. badcontactsoÍS-correction
capacitoÍ
C2427
2. Bad
contacts
oÍflybackcapacrtor
C2425.
3. Shortedflyback
diodeD6421
orD6423.
4. ShortedS-correction
capacttoíC2427.
5. Badsolder
contactsin
the
line
outputstage.
When
EW-protection
has
beenactive,theline
output
transistor
7420may
alsobe
defective.
Vertical-protection
Thevertical
output
stagecreates
VERTICAL-PROTECïON
pulses
ateveryflyback
pulse
when
itis
functioning
correctly.These
pulses
aresensed
by
the
BIMOSlC71
19-4D
on
pin
37.Whenthe
pulse
trainis
interrupted,
theBIMOS
will
switchtoBIMOS
STANDBY
mode.
IntheBIMOS
STANDBYmode,
theBTMOS
switches
oÍftheVDRIVE+
andVDRIVE-
whiletheRGBoutputs
are
blanked.
Circuitbreaker
'l463
may
beopen.Probably,
the
lineoutput
stagewillnotwork
andthe
power
supplywill
switchtohick-up mode
(under
voltage
protection).
Software protection
The
software
protection
ismanaged
bythemicroprocessor.
It
continuouslyverifies
the
presence
ofthe+5
and
+8
supplyvoltages
on
pin
34andthe
activityoÍ
thel2Cbus.
When
the
pÍotection
becomes
active,the
soÍtwarewill
switchthe
power
supplyon
andoffcontinuouslyvia
the
STANDBYline.
In
thissituation
the
power
supply
produces
asqueakingsound.
PCS
82272GB

Service
Modes,
DST,
Error
messages,
- l'C protection
The l2C
busiscontrolled
at eachl2O-command.
ThereÍore
everyl2C
command
hasa defined
starístop
condition.
When
thedefined
start/stop
condítionis
repeatedly
incorrect,
error3 isplaced
intheenor buffer
andthe setswitches
to softwareprotection.
l2C-protection
isgenerated
intheÍollowing
situations:
. SDAshortedto earth
. SCLshoÍted
to earth
. SDAandSCLshorted
WhenSCLorSDAisshorted,
thesettriesto restart
andthe LEDlights
ina clearlyrecognisable pattern.
. SDÁ/SCL
shortedwhenthesetisswitched
ONwith
the mains
switch:
LED
is
8secondsRED,
8seconds
GREEN,flashes
RED,
8seconds
GREEN,
flashes
RED,8seconds
GREEN,
flashesRED,etcetera.
. SDIy'SCL
shorted
duringoperation
LED
is
I seconds
GREEN,flashes
RED,
g seconds
GREEN,
ÍlashesRED,ercetera,
- +SDb
and+8Sc
protection
ofthemicroprocessor
+SDb
and+8Sc
arethe mainsupplyvoltages
ofthe
entire
small
signal
procêssing
oÍthe set.At pin34the
microprocêssor
senseswhether
the supplyvoltages
+SSDb
or+8Sc
coming
fÍom
the
power
supply
are
present.
Whenoneor boththesupply
voltages
are
míssing,
thesetswitches
to soítware
protection.
6.5 Fault
finding
andrepair
tips
Note
thatÍor 21' sets,voltages
andwave
formsmaydiffer.
6.5.1 General
LED
andication
after
start-up
procedure
iscompleted
- NoLED
Setisswitched
OFF,supply problem
or microprocessor
problem.
- LEDcontinuously
Set isin standby,
control
partdeÍective,
standbymode
defective.
- LED
blinking
SetinSDM,
transmitting
errorbufÍer.
Audible checks
- Demagnetisation
audible:
mainsvoltage
ispresent
at
LSP.
- EHTaudible:
supplyis operational
(line
outputstage
onlyworksincaseVOS (+140V
for 25 & 29'; +95V
lor 21")ispresent.
- Hick-up
sound
powersupply
audible:
powersupplyis
shorted.
Check
the LOT (item
5430)
andthe lineoutput
transistor
TS7420.
6.5.2 FaultÍinding inthe powersupply
In
caseofapower
supply
problem,
the
power
supply
can
besimpliÍiedtoastandalone
power
supply
atlowvoltages
(low
risk)
as
Íollows:
Control
part
oÍthepower
supply
1. Disconnect
the
SSP
(as
aresulttheline
will
not
function
anymoreandthereforewill
nolonger
be
a
load
oÍthe
power
supply)ordisconnect
theline
by
removing
jumper
9400andR3400
(ifpresent)
onthe
LSP.
2. ConnectanexternalDC
power
supply
between
supply
pin
11C7520
(via
adiode
-e.g.BYDSÉID
-with
cathode
tosupply
pin
11C7520)andhot
earth
(e.9.
earth
oÍthe
bigsmoothing
capacitorC2505).
3. Connectaoscilloscope
totest
point
P4
atpin
g ICZSZO.
4. Turn
upthe
exteÍnalDCsupplyvoltage
slowlyto17V
DC.
Remark: ThelC stattsatasupplyvoltage
of 14V DC,
afterthatthesupplyvoftage
candropto
approx.9VDC.Atapproximately
18VDC,
overvoftage
protection
becomes
adive,
resultinginasupplyvoftage
drop
below7V
DCbeforeanewstaft-up
isperformed
by
turning
upthesupplyvoftage
above14V
DC.
5. The correct
(measured)
situationis
displayed
in.Other
results
indicate
adeÍectinthe
power
supply
control
part(1C7520
or
peripheral
components
at
pins
10
or
11).
Figure
6.2:
SV/div; SuS/div
+ zlOKHz
pulse
EnergytÍansÍer
oÍthepower
supply
(onlyiÍcontrol
part
isOK)
6. Applyaction1
,2 and4asdescribed
earlier.
7. Connectalamp
of230V/100Wacross
theVOS
output
capacitorC2569.
Connecta 1kQresistor
betweenthe +SSTANDBY
(connector
7L10)andthe STANDBYline (connector
8L10)to switchthe power
supplyto normaloperation.
Connectthe mainsconnector
to aVARIACbut leaveit
at0.
10.Connecta voltmeter
acrossC2569and an oscilloscope
betweenthedrainofTS7541(25& 29) or TS7540
(21")
andhotearth.
11.Slowlyincrease
themainsinput voltage
by
theVARIAC
(in
thiswayfurtherdamageto the powersupplycanbe
avoided).
8.
9.
PCS82 273GB

Protections,
FaultÍinding
and
Repair
tips
The waveformsÍorthe Íollowing
mains
voltage
aÍegiven:
Mainsinvoltage
lOVAC:
2OVAC:
4OVAC:
65V AC:
>65VAC: Stablesituation,
so
40kHz
and140V
Incase
ofafeedback
problem,
the
situation
willnotstabilise
orthevoltagewill
exceed140V
(95V
with
21')
1. Figure
6.3:
Mainsin10V
AC
10v/div; 1Ous/div
2. Figure
6.4:
Mainsin20VAC
20vldiv; SuS/div
+ zlokHz
pulse
+ VOS3OV
3. Figure 6.5:
Mainsin40VAC
S0V/div; SuS/div
ulokHz
pulse
+ VOS8OV
4. Figure6.6:
Mainsin65VAC
S0V/div; SuS/div
+ 40kHzpulse
+ VOS14OV
Fault
findingoÍthehorizontal
circuitry
Whenthe horizontal
circuitryitselÍ
isdefective,hcanbe
simplifiedto a standalone'switched modesupply"
at low
voltages(lowrisk)
asÍollows:
1. Disconnect
thesetÍrom mains.
2. Discoínectthe SSP by removing
allcablesto the SSp.
3. Conneot
an eldemal50V DC (or40V DC)supplywith
current
measurement
possibility
across
C2400.
4. Replace
the HDRIVE
byan eliternalLFgenerator
[fTL
level(between
0 and5V);dutycycle50olo)witha t6 kHz
pulse
atthe baseoÍ TS7410 (near
LOTattheside
ofthe
PCB).
20kHzandVOS7V5
40kHzand VOS30V
ztOkHz
andVOS80V
zlOkHz
andVOS 1,10V
CorrecthóÍizontal
circuitry
Note
thatihèamplitude
oÍthesignalstrongly
dependsonthe
Írequency
ofthe
generator.
2. Figure
6.8:
L3;test
point
atcollectorlineoutput
transiBtor
(7420)
S0V/div; lossidiv
Line deflection open'.
Currentfrom e)dernal
DCsupplyis
appÍoximately
100m4.
Obseruatlon: small pulsefollowed by wide pulseand 100mA
supply current
Causes: horizontal deflection coil open
linearity coil L5421 open
S-conection C2427 open
3. Figure
6.9:
L3;
test
point
atcollectorline
output
transistor
(7420)
SoV/diq 1ops/div
Current
from
externalDG
supply
approx
500m4!!
Obseruatlon: fast oscillationsand 500mA suppty cunent
Cause: horizontal deflection shorted(e.9.line
deflection coil shofted)
Whenthe line
deflection
isnotcompletely
shortedbut
onlya number
of windings
areshorted,thewaveÍorm
doesnotshowthe oscillation
andthe currontof the
e)Íernal DCsupplyisapproximately
200fnA.
4. Figure6.10:
L3;
test
point
atcollectorlineoutpui
transietor
(7420)
1O0V/div;1OpS/div
Currentftom
e)dernalDC
supply
is
approximately150mA
Obseruatlon: flyback
timeisshofter,
oneexta pulse in
between,150mA
supply
cunent
Cause: flybackcapacitor
C2425open
5. Figure
6.11:
L3;test
point
atclllectorline
output
transiÉtor
(7420)
1OOV/div;
1OrrS/div
Curretltfrom
externalDCsupply
>1A
Obseruatlón: 2 pulsespercycleextraand
supptycurrent
from
morethan1A
Cause: short-circuitinpicture
tube
(e.9.
EHT
toAquadag)
6.5.3
5. Connect aoscilloscope
totest
point
L1
outputtransistor7
42Q\.
Possibilities:
1. Figure
6.7:
L3;test
point
atcollector
line
output
transistor
(7420)
S0V/div; lOps/div
CurrerttÍromexternal
DC
supply
approx.100m4
----------------l
ffiffi
l+-t-t-L.trl-t-1-l-lJ
H*#fll-HrflH
fffiffiHtÏf\ffi
rfiiïftj-tH
n--|-rï-rrn-t
ffiffi
Ht+++-llt+i-t_1
Íïï]ïflï-ïïÏ]
F+#+fl-I-rt-fi
frrï--rm-n
ffiffiF
ffiffiffi
l-t--]----l-ff-1
ffiffi
ffi
n-n*-T-|-Ít
(collector
oÍ line
Obseruation: normal l6kHz pulsesand 100mA
supptycurrent