JVC AV28CH1EUS User manual

No.51944
AV28 CH1 EUS
AV28 CH1 EU
B
1COPYRIGHT © 2002 VICTOR COMPANY OF JAPAN, LTD.
Mar. 2002
AV28CH1EUS
AV28CH1EUB
CONTENTS
!SPECIFICATIONS ････････････････････････････････
････････････････････････････････････････････････････････････････
･････････････････････････････････････････････････････････････
･･････････････････････････････････････････････････････････
･････････････････････････････ 2
!SAFETY PRECAUTIONS ････････････････････････････････
････････････････････････････････････････････････････････････････
･･･････････････････････････････････････････････････････
･･････････････････････････････････････････････
･･･････････････････････ 4
!FEATURES････････････････････････････････
････････････････････････････････････････････････････････････････
････････････････････････････････････････････････････････････････
････････････････････････････････････････････････････････････････
･･･････････････････････････････････
･･････
･･･ 5
!MAIN DIFFERENCE LIST ････････････････････････････････
････････････････････････････････････････････････････････････････
･･･････････････････････････････････････････････････････
･･････････････････････････････････････････････
･･･････････････････････ 5
!SPECIFIC SERVICE INSTRUCTIONS ････････････････････････････････
････････････････････････････････････････････････････････････････
･････････････････････････････････････････････
･･････････････････････････
･････････････ 6
!SERVICE ADJUSTMENTS ････････････････････････････････
････････････････････････････････････････････････････････････････
･････････････････････････････････････････････････････
･･････････････････････････････････････････
･････････････････････ 12
!PARTS LIST ････････････････････････････････
････････････････････････････････････････････････････････････････
････････････････････････････････････････････････････････････････
････････････････････････････････････････････････････････････････
･････････････････････････････････
･･
･31
★
STANDARD CIRCUIT DIAGRAM ････････････････････････････････
････････････････････････････････････････････････････････････････
････････････････････････････････････････････････
････････････････････････････････
････････････････2- 1
SERVICE MANUAL
COLOUR TELEVISION
BASIC CHASSIS
MF

No.51944
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V28CH1EUS
A
V28CH1EUB
2
SPECIFICATIONS
Content
Item
AV28CH1EUS / AV28CH1EUB
Dimensions ( W×
××
×H×
××
×D ) 72 5m m×4 80m m×4 96m m
Mass 34 .7 kg
TV RF System CCI R (B/G ,D/K, I ,L, L’)
Co lour Sy st em PA L / SECA M / N TSC (Only i n EXT mo de )
St ere o Sy stem A2 (B/G,D/K )/ NICAM(B/G,I ,D/K, L)
Teletext System FLOF (Fastext)
TOP (German system)
WST(W orld Standard system)
Receiving Frequency
VHF 47 MHz ～47 0M Hz
UHF 470MHz ～8 62MHz
In terme d iat e Fr e
q
uenc
y
VIF Carrier 38.9MHz (B/G , I ,L)/ 33.95 MHz (L’)
SIF Carrier 33.4 MHz (5 .5MHz :B/ G) / 32.9 MHz (6.0MHz:I ) / 32 .4MHz (6. 5MHz:L , D/K) / 40.4 5MHz ( 6.5MHz:L’)
Colour Sub Carrier Fre
q
.
PAL 4.43MHz
SE CAM 4.40625MHz/4.25MHz
NT SC 3.58MHz / 4.43MHz
Power Input AC 2 30V , 5 0Hz
Power Consumption 16 5W (Ma x) / 1 12W ( Avg), sta nd by : 2.8 W
Aerial Input Term 75 Ωun ba lanc ed, C oaxi al
Picture Tube Vi si ble size : 66 cm, M eas ur ed dia gon al ly
Hi g h Volt ag e 30.0kV (at zerobeamcurrent)
Spe ake r (10c m×3c m) ov al typ e ×2
Au dio Output 5W + 5W
EX T-1 /EXT-2/E XT- 3
(Input / Output)
21 -p in E ur o c onn ecto r
(SCART socket)
S/ Video Y : 1V p-p POSITIVE (Negative sync Provided, when terminated with 75 Ω)
C : 0.3Vp-p (Burst signal, when terminated with 75Ω)
EXT-4 (Input) Video
Au dio (L /R )
S/ Video
1V p- p 7 5 Ω( RCA pin ja ck)
50 0m Vrms( -4dB s ) , H igh Impe dan ce ( RCA pin jack )
Y : 1V p-p POSITIVE (Negative sync Provided, when terminated with 75Ω)
C : 0.3Vp-p (Burst signal, when terminated with 75Ω)
AUDIO OUT (Variable) 0～
1 Vrms, Low Imp ed ance
( RCA pi n ja ck×2)
Headphone jack St ereo min i j ac k ( φ3.5mm)
Remote Control Unit R M- C54 H (A AA/R0 3 d r y ba tte ry×2) : (A V2 8CH1 EU S) / RM-C 50(AA A/R0 3 d r y bat tery×2 ) : (A V28CH1EUB)
Design & speci ficatio ns ar e su bje ct to cha nge wi th out no tice.
+1kV
-1. 5kV

No.51944
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V28CH1EUS
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3
■
■■
■21-pin Euro connector (SCART socket) : EXT-1 / EXT-2 / EXT-3
(P-P= Peak to Peak, B-W= Blanking to white peak)
Pin
No . Signal Designation Matching Value EXT-1 EXT-2 EXT-3
1 AU DIO R o ut put 50 0m Vrms(N omi na l),
Low impedance
○
(TV OUT)
○
(LINE OUT) NC
2 AU DIO R i n put 50 0m Vrms(N omi na l),
Hig h i mpe da nce ○○○
3 AU DIO L o utp ut 50 0m Vrms(N omi na l),
Low impedance
○
(TV OUT)
○
(LINE OUT) NC
4 AUDIO GND ○○○
5 GND (B) ○○○
6 AUDIO L input 500mVrms(Nominal),
Hig h i mpe da nce ○○○
7Binput 700mV
B- W , 75Ω○○NC
8 FUNCTION SW
(SLOW SW)
Low : 0-3V, High : 8-12V, High
impedance
○○○
9 GND (G) ○○○
10 SCL3 NC ○NC
11 G i n put 70 0mVB- W , 75Ω○○NC
12 SDA3 NC ○NC
13 GND (R) ○○○
14 GND (YS)○NC NC
15 R / C input R : 700mVB- W , 75Ω
C : 300mVP- P , 75Ω
○
(only R)
○○
(only C)
16 Ys i n put Low : 0 - 0.4, High : 1 - 3V, 75Ω○ NC NC
17 GND(VIDEO output) ○○○
18 GND(VIDEO input) ○○○
19 VIDEO ou tpu t 1V P- P( Nega tive g oi n g sync ), 75 Ω○
(TV)
○
(LINE OUT) NC
20 VIDEO / Y inp ut 1V P- P( Nega ti ve g oin g sync ), 75 Ω○ ○ ○
21 COMMON GND ○○○
[Pin assignment]

No.51944
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V28CH1EUS
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V28CH1EUB
4
SAFETY PRECAUTIONS
1. The d esign of th is pr od uct con ta in s sp eci al har d wa re , ma ny
circuit s and components specially for safety purposes. For
con ti nu ed pr ot ection , n o chan g es sh ou ld b e ma de to the o rig inal
d esign un less a uth or ized in writin g by th e ma nu fact ur er.
Rep l acemen t p ar ts m ust b e id ent ic al to thos e u sed i n th e or igin al
circu it s. S er vice sho ul d b e p er for med by qu alif i ed p ers on nel
on ly.
2. Al te r ati on s of t he desig n or ci rcui tr y of t he pr od ucts sh ould not be
made. Any design alterations or additions will void the
m anu fact ur er 's w arr a nt y and w ill f ur th er r elieve t he ma nu factu rer
of r esp onsib ility for per so na l i njur y or p r op erty d am ag e r esul t in g
th er efr om .
3. M an y e lectri cal an d m ech ani ca l p ar ts i n th e pr od ucts ha ve
special safety-related characteristics. T hese characteristics are
oft en no t e viden t f r om vi sua l i nsp ection n or ca n t he pr o tect io n
aff or de d by th em nece ssar ily b e ob tain ed b y u sin g r ep lacem en t
com po ne nts ra ted f or hig he r vo ltag e, w att ag e, etc. Rep l acemen t
p arts wh ic h ha ve th ese sp ecial s afet y ch ar act er ist ics ar e
identified in the parts list of Servic e manual. El ec tric al
components having such features are identified by shading
on the sche matics and by (!
!!
!) on the parts list in Service
manual. The us e of a sub stitu te r ep la cemen t whi ch do es n ot
h ave th e sam e saf ety ch ar act er ist ics as t he r eco mmen de d
r eplac em ent par t sh own i n th e p ar ts l ist of S er vice m an ual m ay
cause shock, fire, or other hazards.
4. Do n't shor t between the LIVE side ground and ISOL ATED
(NEUTRAL) side ground or EARTH side ground when
repairing.
Some model's power circuit is partly different in the GND. The
diff er enc e of th e G ND i s sho wn b y th e LIV E : (") side GND, the
ISO LATE D(N EUTRAL) : ( #) side G ND and EARTH : ($) side
GN D. D o n't sh or t b et we en th e LIV E sid e GND an d
ISO LATE D(NEUTRAL) side GND or EARTH side GND and
n ever m ea sure w it h a m ea sur ing a ppa r atus ( oscillo scop e etc.)
th e LI VE sid e GND an d IS OLA TED (NE UTRAL ) sid e G ND or
EARTH side GND at th e s ame time.
If above note will not be kept, a fuse or any parts will be broken.
5. If any repair has been made to the chassis, it is recommended
th at t he B1 set ting shou ld b e ch ecke d or adj u ste d (Se e
ADJUSTMENT OF B 1 POW E R SU PPLY) .
6. The hi gh volta ge app lie d t o th e pi ctu r e tu be mu st con form w it h
th at sp ecified i n S er vice m an ual. E xcessive h i gh vo lt ag e ca n
cau se an incr e ase in X- Ray em ission , ar cing an d possib le
component damage, therefore operation under excessive high
voltage conditions should be kept to a minimum, or should be
preve nt ed. If s ever e arc in g occurs, r em ove t he AC power
imm ed iate l y an d de term ine th e ca use b y visua l i nsp ect io n
( in corr ect in stall at i on, cr acke d or m elte d hi gh vo lt age har n ess,
p oor so ld eri ng, et c.). To m aint ain the p r ope r min imu m l e vel of
sof t X- Ray em issi on, c omp on en ts i n th e high voltag e ci rcui tr y
incl ud ing t he pict ur e tu be must b e t he e xact r ep lacem e nts or
alte rn at ives ap pr ove d b y th e ma nuf act ur er of th e c om plet e
pr od uct.
7. Do n ot c hec k high volt ag e b y drawing an ar c. Use a high volt ag e
m eter or a hi g h v ol tag e pr ob e wit h a V TVM . Di scha rg e th e
picture tube before attempting meter connection, by connecting
a cli p le ad to th e gr ou nd f ra me a nd c onn ectin g th e oth er end of
the lead through a 10k
Ω2W resisto r to the an od e b utt on .
8. W hen se r vi ce i s r equ ire d, ob ser ve th e or igina l l ea d dr ess. E xtra
pr ec aut i on sh ou ld b e g i ve n t o assur e cor rect lea d dr ess in th e
hig h vol tag e ci rcuit a r ea. W here a s hor t cir cuit h as occu rr e d,
th ose co mp on ent s tha t i ndica te evide nce of ove r hea ti ng sho ul d
b e r e place d. A l wa ys u se th e ma nuf act ur er's rep l acemen t
components.
9. Isolation Check
(Safety for Electrical Shock Hazard)
Af ter r e-ass emb lin g th e p r odu ct, al ways per f orm an i solat io n
ch eck on the expo sed me tal p arts of t he cabin et ( a nte nn a
ter m ina ls, vid eo /au di o i npu t and ou tpu t t er min als, C on tr ol kn obs,
m etal cabi n et, screw he ad s, ea r ph one j ack, con trol shaf ts, etc.)
to be su re th e p r odu ct i s s af e t o o pe r ate wi th ou t d an ger of
elect rical shoc k.
(1) Dielectric Strength Test
The i so l ati on be tween the A C pr ima ry circu it an d al l me tal p ar ts
exp ose d t o th e us er , p ar ti cular ly an y e xp os ed met al p art h avi ng a
r etu rn p ath to t he chass is sho ul d withs tan d a volt age of 3 000 V
AC (r.m.s.) for a period of one second.
( . . . . W it hstan d a vo lt ag e of 1 10 0V A C ( r.m. s.) t o an ap pli anc e
r ate d up to 12 0V , an d 3 00 0V AC ( r .m. s.) to an ap pl ian ce r at ed
200V or more, for a periodof one second.)
This method of test requires a t est equipment not g enerally found
in t he servic e trad e.
(2) Leakage Current Check
Pl ug th e A C l in e c ord d ir ect l y in to th e A C ou tlet ( d o n ot use a lin e
isol atio n transf or mer du rin g this ch eck.) . U sin g a " Lea kag e
Cur r ent Teste r", me asur e th e l ea kag e cu rre nt f rom each exp osed
m etal p art of the ca bine t, p art icu lar ly any e xpos ed me tal p art
h aving a re turn pa th to t he ch assis , t o a kn own go od ea rt h
gr ou nd (wa ter pip e, e tc.). An y leaka ge cur r en t m ust n ot e xceed
0.5mA AC (r.m.s.).
How eve r, i n tr op ic al ar ea , th is mu st no t exce ed 0.2 mA AC
(r.m.s.).
"
""
"Alte rnat e Che ck M et ho d
Pl ug th e A C l in e c ord d ir ect l y in to th e A C ou tlet ( d o n ot use a lin e
isol atio n tr an sfor mer duri ng t hi s che ck.). Use an AC vo lt me ter
h aving 1 00 0 oh ms pe r volt or mor e sens it i vity in th e fo ll owing
m ann er. Con nec t a 1 50 0Ω10W res ist or par a ll e le d b y a 0 .1 5µF
AC -type c apa cit or bet we en an expo sed met al pa rt a nd a kno wn
g ood e ar th gr o un d ( wa ter pipe , etc.). M eas ur e th e A C vo lt ag e
acr oss th e r es ist or w ith th e AC vo ltm eter . M ove th e r esistor
con nec ti on to e ach exp ose d me tal par t, p art i cul arl y a ny exp osed
m etal p ar t havin g a r etu rn pat h to t he ch assis, an d m easu r e th e
AC vol tag e ac ro ss the r es ist or . No w , re verse th e pl u g i n th e AC
ou tl et and r e pe at eac h m ea sur emen t. An y vol t ag e me asu re d
must not exc eed 0 .7 5V AC (r.m.s.). This c orresponds to 0.5mA
AC (r.m.s.).
However, in tropical area, this must not exceed 0 .3V AC ( r.m. s.).
This corresponds to 0.2mA AC (r.m.s.).
0.15μF AC-T YPE
1500 Ω10W
GOODEARTH GROUND
PLACE THIS PROBE
ON E A C H EX PO SE D
ME T AL PA R T
ACVOLTMETER
(HAVING 1000 Ω/V,
OR MOR E SENSIT IVITY)

No.51944
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FEATURES
"New chassi s d esign ena bl e us e of an i nte rac tive on scr een
control.
"The TELETEXT SYSTEM has a built-in FASTEXT (UK system),
TOP (German system) and W ST (world standard system)
system.
"Be caus e th is TV un it cor r esp on ds t o m ultipl e x br oa dca st, u sers
can enjoy music programs and sporting events with live realism.
In ad dition , BI LIN GU AL pr o gram s can b e h ear d in th eir or ig in al
language.
"Users can make VCR dubbing of picture and sound by controlling
th e AV selec tor to se le ct an o ptio na l so urc e at th e EXT -2 outp ut
sh own in figu re.
MAIN DIFFERENCE LIST
!ModelName
Par t Name AV28CH1EUS AV28CH1EUB
!FRONT C ABINET A SS Y LC 10 001- 00 8C- U LC 10 001- 00 9B-U
!DOOR LC 20 001- 01 0A-U LC 20 001- 01 2A-U
!POW ER KNOB LC 30 104- 01 0A-U LC 30 104- 01 2A-U
!REA R COVER LC 10 03-009 B- U LC 10 003- 01 0B-U
JVC MARK LC 40 354- 00 3A-U LC 40 354- 00 1C- U
!RATING LABEL LC 11 414 -00 1A- U LC 11 414 -00 2A- U
EURO LABEL AEM1064-009-E AEM1064-010-E
REMOTE CONTROL U NIT RM-C54H-1C RM-C50-1C
TV EXT-1 EXT-3
EXT-2
EXT-4

No.51944
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SPECIFIC SERVICE INSTRUCTIONS
DISASSEMBLY PROCEDURE
REMOVING THE REAR COVER
1. U np lu g t he po we r c or d.
2. Remove the 14 screws marked !
!!
!as sh own in th e Fi g. 1.
3. W ithdra w t he r ear co ver to wa rd you .
REMOVING THE CHASSIS
"After removing the rear cover.
1. Sl ight l y r aise th e bo th si de s of th e c hassi s by h and and r e mo ve
th e t wo cl aws u nd er th e b oth sid es of the ch assis fr om t he fr o nt
cab inet .
2. W ithdra w t he chass is backwa rd .
(If necess ary, take off the wire clamp, connectors etc.)
REMOVING THE AV TERMINAL BOARD
"After removing the rear cover.
1. Remove th e 2 screws m ar ked "
""
"as sh ow n in th e F ig. 1.
2. Remove the claws marked #
##
#un der t he CHAS SIS as sho wn in
Fig. 2.
3. Slight ly in t he dire ction of arrow $
$$
$as sh own in Fig. 2.
REMOVING THE SPEAKER
"After removing the rear cover.
1. Remove t he 2 screws m ar ked %
%%
%as sh own in F ig. 1.
2. Fol low th e s am e st eps wh en r emovi ng th e oth er ha nd spe ake r.
CHECKING THE PW BOARD
To ch eck the b ack si de of th e PW B oar d.
1) Pull out the chassis . (Refer to REMOV ING THE CHAS SIS ).
2) Erect the c hassis vertically so that you can easily check the
b ack side of th e PW B oar d.
[CAUTION]
"When erecting the chassis, be careful s o that there will be no
contacting with other PW Board.
"Be fore turn in g on po wer , ma ke sur e t ha t the w ire co nn ecto r i s
pr op erl y con nec ted .
"W hen co ndu cting a ch eck w ith p ow er su ppl ied , b e sure to c onfir m
th at t he CRT E ARTH W I RE (B RA IDED AS S’Y) is co nne cted t o
th e C RT SOCKE T PW b oar d.
WIRE CLAMPING AND C ABLE TYING
1. Be sure t o clamp the wire.
2. N ever r emo ve th e c abl e tie use d f or tying th e w ire s to ge the r.
Sh oul d i t be in adve rt ent ly r em ove d, b e su re to tie th e wir es wit h
a n ew c able tie.
Fig . 2
AV SE L PW B
AV TERMINAL
BOARD
C
C
D

No.51944
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FRONT CABINET
CRT
SOCKET
PWB
FRONT
C ONT RO L
PWB POWER & DEF. PWB
CLAW
CLAW
MAIN PWB
C ONT RO L BA SE
CHASSIS
REAR COVER
Fig . 1
AV TERMINAL
BOARD
S
PEAKER
AV SW PW B
E
B
FBT
MICON PWB
10 0Hz PW B
A

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REMOVING THE CRT
∗Rep l acemen t of th e CR T sho ul d be p erfor med b y 2 or mor e
p ers ons.
•Af ter removing the c over, chassis etc.,
1. Pu tti ng th e CR T c han ge ta ble o n sof t cloth , th e C RT cha ng e ta bl e
sh ould also b e c overe d with s uch soft clot h ( sho wn in Fig. 3).
2. W hil e kee pin g th e s urf ac e of CRT down , m ou nt the TV s et o n t he
CRT change table balanced will as shown in Fig.4.
3. Rem ove 4 sc re ws marke d by arr o ws wi th a b ox typ e scr e w dr iver
as s hown in Fig. 4.
•Si nc e th e cab i net wi ll dr op w h en scr ews h ave b een r em o ve d, b e
sure t o support t he cab in et with h an ds.
4. After 4 screws have been removed, put the cabinet slowly on
cloth (At this time, be ca refully so as not to damage the front
sur fac e of th e c abi n et) sh ow n in F ig.5 .
•The C RT sh oul d b e ass em bled accor din g to th e o pp osite
sequence of its dismounting steps.
∗The C RT cha ng e t ab le sh ould pr ef er ab ly b e sm aller t hat th e CRT
sur fac e, and i ts h ei gh t b e abo ut 35c m.
COATING OF SILICON GREASE FOR ELECTRICAL
INSULATION ON THE CRT ANODE CAP SECTION.
•Su bse qu ent to re plac em en t of t he CRT an d HV tr an sfor m er o r
r epa ir of t he an od e ca p, etc. by d is mo unt i ng the m, be sure to coa t
silico n g re ase fo r el ectri cal i nsu l ati o n as sh ow n in Fig .6 .
W ipe a r oun d t he an od e b utt on with cl ea n and dr y cl ot h. ( Fig. 6)
Coat silic on greas e on t he sect ion arou nd th e a no de bu tt on. At
this time, take care so that any silicon greases dose not stic k to
the anode button. (Fig.7)
★
★★
★Silicon grease product No. KS - 650N
CRT CHANGE TABLE
CLOTH
AP PROX.
35 cm
CRT
CRT
CHANGE
TABLE
BOX
TYPE
SCREW
DRI VER
Fig. 3
Fig. 6 Fig. 7
Ap pr ox.
20mm (Do not
coat grease on
this s ection
Silic on gr eas e
sh ould be coa ted
b y 5mm or m or e
fr om th e outs id e
dia me ter of
an od e c ap.
An od e b utt on
(No sticking of
silicon grease)
Coat in g posit io n
of si lico n g r ease
An od e ca p
An od e b utt on
CRT
Silic on gr eas e
coating
Fig. 5
CRT
CABINET CRT
CHANGE TABLE
Fig. 4

No.51944
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REPLACEMENT OF CHIP COMPONENT
!CAUTIONS
1. Avoid heating for more than 3 seconds.
2. D o n ot ru b t he el ect ro des an d t he r esi st p arts of th e p att er n.
3. W hen r emoving a c hi p par t, m elt th e s ol der ad equ ate ly.
4. D o n ot r euse a ch i p p ar t afte r re mo vi ng it .
!SOLDERING IRON
1. Use a hig h ins ulatio n s oldering iron with a t hin po in ted end of it .
2. A 3 0 w s ol dering i ron is r ec om mend ed for easi ly r emovi ng p ar ts.
!REPLACEMENT STEPS
1. How to remove Chip parts
#
##
#Resi st ors, ca pa citors , et c
( 1) As sh own i n t he f ig ure, pu sh th e pa rt w ith twee zers and
alte rn at ely m elt th e solde r at each en d.
( 2) Sh if t wi th tweeze rs an d r emo ve th e ch ip p ar t.
#
##
#Trans ist ors, diodes , va ria bl e r es ist or s, et c
( 1) Ap ply e xt ra so ld er to ea ch l e ad .
( 2) As sh own i n t he f ig ure, pu sh th e pa rt w ith twee zers and
alte rn at ely m elt th e sol d er a t each le ad . S hi ft an d r em ove t he
chip part.
Note : After removing t he part , remove remaining solder fro m the
pattern.
2. How to install Chip parts
#
##
#Resi st ors, ca pa citors , et c
(1) Apply solder to th e p att ern as indic ated in the figure.
( 2) Grasp t he ch ip p art with twee zer s and plac e i t on th e s ol d er.
The n h ea t an d me lt th e so ld er a t b oth en ds of t he chi p par t.
#
##
#Trans ist ors, diodes , va ria bl e r es ist or s, et c
(1) Apply solder to th e p att ern as indic ated in the figure.
( 2) Grasp th e ch ip p art w it h t we eze rs an d p lace it on th e so lder .
(3) First s older lead Aas indicated in t he figure.
( 4) T he n so ld er l e ads Band C.
SOLD E R SOLD E R
A
B
C
A
B
C

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REPLACEMENT OF MEMORY ICs
1. Memory ICs
This TV use memory ICs. In the memory ICs, there are memorized data
for cor rectly op er atin g th e vid eo an d def l ecti on circu its . W h en r ep laci ng
memory ICs, b e s ure t o us e ICs writte n with th e initial values of da ta.
2. Procedure for replacin g memory ICs
PROCEDURE
(1) Powe r off
Sw itch the p ow er of f an d un pl ug th e p ow er cor d f ro m t he ou tl et.
(2) R epla ce ICs.
Be sure to use memory ICs written with the initial data values.
(3) Powe r on
Pl ug th e p ow er c or d i nt o th e ou tlet a nd sw it ch t he po we r on .
(4) Check and set SY STEM CO NSTANT SET :
*
**
* It mus t not adjust wit hout sig nal.
1) Pr ess th e IN FO RM ATI ON ke y an d th e MUTING key of th e
REMOTE CONTROL UNIT simultaneous ly.
2) The SERVICE MENU screen of Fig. 1 will be displayed.
3) W hil e th e S ERVICE ME NU is d is pl aye d, pr es s th e
INFORMATION key and MUTING key s imult aneously, and t he
SYSTEM CONSTANT SET screen of Fig. 2 will be displayed.
4) Check th e se tti ng va lu es of the S YSTEM C ON STA NT SET of
Table 1. If th e value is d if ferent, select the s etting item with the
FUNCTION UP/DOWN key, and s et the c orrect value with the
FUNCTION -/+ key.
5) Press the MENU key to memorize the setting value.
6) Pr ess t he INFORM ATION ke y t wice, a nd r etu rn t o th e no rm al
screen.
(5) Se tt ing o f re cei ve ch anne ls
Se t th e r ec eive ch an ne l.
For setting, ref er to the OPERATING INS TRUCTIONS.
(6) U ser se ttings
Check th e us er sett in g val ues of Tab le 2, an d i f sett in g value i s
diff er ent , set th e c orrec t valu e.
For setting, ref er to the OPERATING INS TRUCTIONS.
(7) Setting of SERVICE MENU
Ve rif y the set ting it ems of th e SE R VICE M E NU of T ab le 3, an d r ese t
where necessary.
For se tting, ref er to the SE RV ICE ADJUSTMENTS.
Na mes of ke y
i
ii
i
▼
▼
▼
▼
INFORMATION
MUT I N G
FUNCTION UP/DOWN
ME NU
FUNCTION -/+
ke y
OK
NAME OF REMOTE CONTROL KEY
SE RV ICE MENU
1. IF 2. V/C
3. A UDI O 4. D EF
5. VSM PRESET 6. STATUS
7. P IP 8. -- -
9. SHIPPING (OFF) 0. BUS FREE
1 -9 : SE LE CT
i : EXIT
Fig.1
SY STE M CON ST ANT S ET
1. DESTINATION EU
- /+ : STORE i : EXIT
OK
Fig.2

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SETT ING VALU ES OF SYST EM CONSTANT SET (TABLE 1)
Setting item Setting content Settin
g
v alue Setting item Setting content Setting value
DESTINATION EU DOLBY NO
CRT TYPE 16 :9 BB E NO
PURITY NO PROGRESSIVE NO
PICTURE TILT NO TDA9178 NO
DIGIP URE PRO NO TONE I C NO
PIP NO FLAT NO
PIC&TE XT NO
USER SETTING VALUES (TABLE 2)
PICTURE SE TTING EX T SETTI NG
TINT COOL
CONTRAST / BRIGHT
SHARP / COLO UR
ID
S-IN
DUBBING
BLANK
BLANK
EXT-1→EX T-2
PICTURE FEATURES FEATURES
DIGITAL VNR AUTO
Digipure PRO AUTO
COLO UR S YSTE M TV : Acco rd in g t o p r eset C H
EXT : AUTO
4:3 AU TO ASPE CT PA NO RA MIC
SL EEP TIME R
BL UE BA CK
OFF
ON
SOUND SET TING INSTALL
BA SS / TREBL E / BA LANC E LA NG UA GE ENGL ISH
HYPER SOUND OFF EDIT/MANUAL PRESET CH only
The ot her s : BLA NK
SERVICE MENU SETING ITEMS (TABLE 3)
Setting item Setting value Setting item Setting value
1. IF 1. VCO
2. ATT ON/OFF
4. DE F. 1. V- SHIFT
2. V-SIZE
3. H-CENT
4. H-S IZE
5. TRAPE Z
6. EW - PIN
7. COR-PIN
8. COR-UP
9. COR-LO
10. ANGLE
11 . BOW
12. V-S.CR
13 . V- LIN
2. V / C 1. RGB B LK
2. W DR R
3. W DR G
4. W DR B
5. BRIGHT
6. CONTRAST
7. COLO UR
8. HUE
9. SHARP
10. VCO A DJ .
3.A UDIO
(Do not adjust)
1. ERR LI MIT
2. A2 ID THR
5. VSM P RE SET
COOL
NORMAL
WARM
1. CONT.
2. BRIGHT
3. SHARP
4. COLO UR
5. HUE
6. W DR R
7. W DR G
8. W DR B
9.S HI PPI NG
(Do not adjust)
ON/OFF
6.S TATU S
(Do not adju st)
VP S
PDC
EKEU EI
4:3
YE S
NO
2TUNER1TUNER
YE S
NO
YE SNO
16 :9
YE SNO
NO
YE SNO
CENTER
YE SNO
YE SNO
YE S
NO
YE SNO
YE S
NO
REFER to VSMPRESET

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SERVICE ADJUSTMENTS
BEFORE STARTING SERVICE ADJUSTMENT
1. There ar e 2 w ays of adjusting this TV: One is wi th the
REMOTE CONTROL UNIT and the other is the conventional
method using adjustment parts and components.
2. The setting (adjustment) using the REMOTE CONTROL
UNIT is made on the basis of th e initial setting values. The
se tting va lues wh ic h a dj ust the sc ree n to t he opt imum
condition can be differ ent from the initial setting values.
3. Make s ure that conn ect ion is c orrect ly ma de t o AC power
sourc e.
4. Tur n on th e powe r of th e TV a nd m easu r in g instrum en t for
war min g u p f or at l east 30 m in ut es b ef or e sta rt in g adj u stm ent .
5. If th e r ec ei ve or inp ut sig nal is not sp ecified , use t he m ost
ap pr op ria te s ig na l f or a dj ust me nt.
6. N ever tou ch p ar ts ( such as var iab le r esist or s, tran sform ers an d
condensers) not shown in the adjustment items of this service
adjustment.
7. Pr ep ar atio n f or ad justmen t ( pres etti n g):
Unl ess oth er wis e sp eci fied i n th e a dj ust me nt it em s, p r ese t th e
follo win g fu nct io ns with th e REMOTE CO NTROL UNI T.
"Setting p osit ion
PICT URE MODE (VSM) NORMAL
SLEEP TIMER OFF
TONE BALAN CE CENTER
ZOOM PANORAMIC
MEASURING INSTRUMENT AND FIXTURES
1. DC voltmeter (or digital voltmeter)
2. Oscilloscope
3. Signal g en erat or (Patt ern g enerat or) [ PAL / SE CA M / NTSC]
4. Remote control unit
ADJUSTMENT ITEMS
●Check in g i t ems.
●Adju stment of FOCUS & SCREEN
●VS M p r eset ad ju st s ettin g.
●VIDEO / CHROMA circuit adjustment.
●DEFLECTION c ircuit adjustment.
●AUDIO circuit adjustment. (Do not adjust)

No. 51944
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ADJUSTMENT LOCATIONS
E1
CN009
CN013
TP-E
CRT SOCKET PWB
(
SOLDER SIDE
)
TOP
FRON T
MAIN PWB POWER&DEF PWB
FRON T
CN006
AV SEL PWB
TUNER
CN002
IC701
IC702
MEMORY
WDEG
1pi n:B1(TP-91)
2pi n:NC
3pi n:NC
4pi n:NC
5pi n:GN D
5
1
X
FRONT CONTROL PWB
FRON T
HV
SCREEN
FO CUS1
TP-47B
CN014
CN008
CN001 SP R
PW
F90 1
POWERSW
SP L
F
100Hz PWB
MICOM PWB
TP-47R
TP-47G
FO CUS2
HVT

No. 51944
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BASIC OPERATION SERVICE MENU
1. TOOL OF SERVICE MENU OPERATION
Operate the SERVICE MENU with the REMOTE CONTROL UNIT.
2. SERV ICE MENU ITEMS
W ith the SERVI CE M EN U, var iou s sett in gs ( ad ju stmen ts) c an b e m ade , a nd th ey a re b r oad ly c la ssif i ed i n th e f oll owing i te ms of set tings
(adjus tments ):
(1) 1. IF ･･･････ ･････････････ ･･･ This mode adjust s the setting values of the IF circuit.
(2) 2.V /C ･･･････ ･････････････ ･･ This mode adjust s the setting values of the VIDEO / CHROMA circuit.
(3) 3.AUDIO･･･････ ････････････ This mode adjusts the setting values of the multiplic ity SOUND circuit.
(4) 4. DEF ･･･････ ･････････････ ･ Thi s m od e adjust s th e se tting val u es o f th e DE FLEC TION ci rcuit f or eac h as pect m od e g i ve n be lo w.
FULL (100/120Hzi)
PA NO RA MIC ( 100 /12 0H z i )
SUBTITLE (100/120Hzi)
COMP RE SS (Fi xed val u e) ( 100 /1 20Hzi )
(5) 5.V SM PRESE T･･･････ ･･････ Thi s m od e adjust s th e i n iti a l s ett in g va lues of CO OL, N ORM AL an d W AR M.
(VSM : Video Status Memory)
3. BASIC OPERATION OF SERVICE MENU
(1) Ho w to enter SERVICE MENU
Press the INFORMATION key and the MUTING key of the
REMO T E C ON TRO L U NI T simu lt an eou sl y, an d th e
SERVICE MENU screen of Fig. 1 will be displayed.
(2) Selection of SUB MENU SCREEN
Press one of keys 1～5 of the REMOTE CONTROL UNIT
an d sele ct th e S UB M ENU S C REEN ( See Fi g. 3 ), fo rm th e
SERVICE MENU.
SERVICE MENU →SUB ME NU
1. IF
2. V / C
3. AUDIO
4. DE F.
5. VS M PR ESE T
6. STATUS
7. PI P
8. ---
9. SHIP PING(OFF)
0. BUS FREE
Na mes of ke
y
i
ii
i
▼
▼
▼
▼
INFORMATION
MUT I N G
FUNCTION UP/DOWN
ME NU
FUNCTION -/+
ke
y
OK
SE RV ICE M ENU
NEME OF REMOTE CONTOROL KEY
Fig.2
Do no t W ork
SE RV ICE MENU
1. IF 2. V/ C
3. AU DIO 4. DE F
5. VS M PRESET 6. ST ATUS
7. PI P 8. -- -
9. SH IPPING ( OFF) 0. BU S FREE
1 -9 : SE LE CT i : EXIT
Fig.1

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1. RGB BL K
2. WDR R
3. WDR G
4. WDR B
5. BRIGHT
6. CONTRAST
7. COLOUR
8. HUE
9. SHA RP
10.VCO ADJ
SERVICE MENU
V/C
1. RGB_BLK
****
2. V/C
PAL
- / + : STORE i : EXIT
OK
DEF *** Hz FUL L
1. V- SHI FT
4. DEF
***
- / + : STORE i : EXIT
OK
1. V- SH IF T
2. V- SIZ E
3. H-CENT
4. H-SIZE
5. TRAPEZ
6. EW -PIN
7. COR PIN
8. COR-UP
9. COR-LO
10.A NGLE
11.B OW
12.V- S.CR
13.V-LIN
IF S ER VICE MENU
1. VCO
2. AT T O N/O FF
1-2 : SELECT i : EXIT
SERVICE MENU
1. IF 2. V/C
3. AUDIO 4. DEF
5. VSM PR ESET 6. STATUS
7. PIP (OFF ) 8. - - -
9. SHIPPING (OFF) 0. BUS FREE
1-9 : SELECT : EXITi
1. ERR L IMIT
2. A2 ID T HR
AUDIO
3. AUDIO
1. ERR LIMIT 10H
C_AD_BIT S =
* ** *** **
- / + : STORE i : EXIT
OK
1.IF(VCO)
COOL
NORMAL
WARM
5. VSM PRESET
VSM PRESET NORMAL
1.CONT
***
- / + : STORE i : EXIT
OK
1. CONT.
2. BRIGHT
3. SHA RP
4. COLOUR
5. HUE
6. WDR R
7. WDR G
8. WDR B
Do not mo ve
Do not adjust
Fig.3 SUB MENU SCREEN

No. 51944
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( 3) M eth od of Set ti ng
1) M eth od of Set ting 1. IF
[VCO] ･･･････ ･････････････ ････････ It mus t not adjust wit hout signal.
①1 K ey･･･････ ･････････････ ･････ Select 1.IF.
②1 K ey･･･････ ･････････････ ･････ Se lect 1.VCO(CW)
Makesurethat thearrow positionbetween the ABOVE REFandBELOWREF.
③INFORMATION Key ･･･････ ･････ Return t o the SERVICE ME NU screen.
2) M eth od of s ett in g 2.V/C, 3.AUDIO, 4.DEF an d 5.VSM PRESET.
①2～5 K ey･･･････ ･････････････ ･･ Select one from 2.V/C, 3.AUDIO, 4.DEF an d 5.VSM PRESET.
②FUNCTION UP / DOWN Key ････ Select s etting items.
③FUNCTION -/+･･･････ ･･････････ Set (adjust) th e setting values of the setting it ems.
④ME NU Key ･･･････ ･････････････ Memorize the setting value.
( Bef or e st orin g t he s ett in g valu es i n me mo r y, do no t pr ess t he C H, TV , P OW ER ON / OF F key -
if you d o, the values will not be stored in memory.)
⑤INFOMATION K ey ･･･････ ･･････ Return t o th e SE RVIC E ME NU scr ee n.
3) Cannotsetting6.S TAT US, 7. PIP, 8. --- , 9 .SHIP PING( OFF) & 0.BU S FREE .
(4) R ele as e of SERV ICE M E NU
1) Af ter co mp l eting th e se tti ng , r et ur n t o t he SERVICE ME NU, th en ag ai n p r ess th e I NFORM ATIO N ke y.

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ADJUSTMENTS
CHECK ITEM
Item Measuring
instrument
Test
p
oint Ad justment part Description
Check of B1
Power Supply
Signal
generator
DC v o ltm et er
Remote
control unit
TP-91(B1)
TP-E(#
##
#)
[X connector
on POWER
DE F PW B ]
1.R G B BL K 1. R ecei ve a an y br oa dca st.
2. Pu sh t he “ZOOM ” ke y an d s el ect the FU LL m ode .
3. Select 2 . V/ C from the SERVICE ME NU.
4. Select 1 . RGB BLK with function UP / DOWN key.
5. Press the function +( ) key to find th e cut off screen (Black
screen).
6. C on nect a DC vol tm et er t o T P-9 1(B 1) a nd TP-E( #).
7. M ake sur e t hat th e vol t ag e is D C13 9.9 ±2.0V.
8. Press the function – ( ) key t o return to s ervice menu..
Check of High
Voltage
Signal
generator
DC volunteer
Remote
control unit
CRT anode
Ch ass is
GND
1.R G B BL K 1. R ecei ve a an y br oa dca st.
2. Pu sh t he “ZOOM ” ke y an d s el ect the FU LL m ode .
3. Select 2 . V/ C from the SERVICE ME NU.
4. Select 1 . RGB BLK with function UP / DOWN key.
5. Press the function +( ) key to find th e cut off screen (Black
screen).
6. Connect a DC voltmeter to CRT ANODE and chassis GND.
7. M ake sur e t hat th e vol t ag e is D C 3 1.0 kV .
8. Press the function – ( ) key t o return to s ervice menu.
Check of VCO Remote
control unit
1. VCO "Und er n orma l c ond itions, no ad j ust me nt is r e quir ed .
"Conf ir mat io n a djust me nt.
1. Sele ct 1 .IF f rom t he SERVICE MENU.
2. Then se lect 1.VCO from th e IF S ERVICE MENU.
3. R ecei ve an y br o adc ast.
4. Check t he arrow ( ) p osi tion be tween th e A BOVE R EF. and
BE LOW REF.
+1kV
-1.5kV
TO O HI GH
ABOVE REF
JUST REF
BELOW REF
TO O L O W
i : EXIT
VCO(CW) **** MHz
MAI N
1. VCO
2. ATT ON/OFF
i : EXIT
IF SERVIC E MEN U
1-2 : SELECT
(Do not move)

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ADJUSTMENT OF FOCUS & SCREEN
Item Measuring
instrument
Test point Ad justment part Description
DAd ju st ment
of
FOCUS
Signal
gener ator
FOCUS VR
[In HVT]
1. R ecei ve a cr oss -h atc h si gn al. S el ect FU LL m ode .
2. W hil e w atc hing th e screen , a djust th e F OCUS VR to m ake th e
ver tical and ho rizo nta l lin es as f in e a nd sha rp as possib l e.
3. M ake sur e th at w hen the sc re en is d ar ke ned , the li nes r e ma in
in good focus.
Ad justment of
SCREEN
Signal
gener ator
SCREENVR
[In HVT]
1 Pr ess a w h ole b la ck sign al
2 Press the ZOOM key and select the FULL mode.
3 Select 2. V/ C from the SERVICE ME NU.
4 Turn t he SCREEN V R clockwis e f rom the f ull co unt er
clockwis e p osi tion an d st op i t a t th e po int wh er e “ CLOW ” stat us
(marke d in Fig.) ch ang es f ro m 1 t o 0 to 1 (which is
indic ated at the 3 rd column from the right.)
5 The n t ur n th e SCRE EN V R cou nt ercl o ckwis e, an d st op wh er e
th e “ CLOW ” stat us ch an ges 1 t o 0
＊“ CLOW ” : c ontro l loop ou t of win do w.
VSM PR ES ET AD JUST SET TIN G
Item Measuring
instrument
Test point Ad justment part Description
Setting of
VS M PRE SET
Remote
control unit
1. CONT .
2. BR IG HT
3. SHARP
4. COLOUR
5. HUE
6. W DR R
7. W DR G
8. W DR B
1. Se le ct 5 .VS M P RESET from th e S ER VICE ME NU.
2. Select CO OL with the MENU key of t he re mote control unit.
3. Adjust the FUNCTION UP/DOWN and -/+ key to bring the set
valu es of 1.CON T ～8. WDR B to the values shown in the
table.
4. Press the ME NU key a nd m emor iz e th e s et va l ue.
5. Respectively s elect the VSM PRESET mode for NORMAL and
W ARM, an d m ake si mil ar a dj ust me nt as i n 3 abo ve.
6. Press the ME NU key a nd m emor iz e th e s et va l ue.
∗Refer to OPERATING INSTRUCTIONS for the PICTURE
MO DE.
Setting item
VSM preset mode
1.CONT. 2.BRIGHT 3.SHARP 4.COLOUR 5.HUE 6.WDR R 7.WDR G 8.WDR B
COOL +130 -11+1 0 -17-9 0
NORMAL 00-110000 0
WARM -13 0 -11 -1 0 +4 0 0
SE TTING VALUES OF VSM PR ESET
SCREEN VR
HVT
FOCUS VR
V/C
1. RGB BLK
00
CLOW
status
- / +
: STORE i : EXIT
OK
0 0 0 0 0 1 0 0
PAL
S
ERVI
C
E M
O
DE
SC
REEN

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VIDEO / CHROMA CIRCUIT ADJUSTMENT
The setting (adjustment) using the REMOTE CONTROL UNIT is made on the basis of the initial setting values.
The setting values which adjust the screen to the optimum condition can be different from the initial setting values.
Setting item
(Adjustm ent item) Initial setting v al ue
2. V/C PAL SE CAM NT SC
1.R G B BL K
2.WDR R 0
3.WDR G 0
4.WDR B (Do not adjust) -12
5. BRIG HT 0
6.CONTRAST 0
7.COLO UR 000
8. HUE +20
9.SHARP (Do not adjust) +7
11.VID AGC (Do not adjust) 0
12.SYC SLI +7
13.A MOVIE +1

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Item Measuring
instrument Test point Ad justment part Description
Ad ju st ment
of
WHITE
BALANCE
(High Light)
Signal
gener ator
Remote
control unit
2. W DR R
3. W DR G
4. W DR B
(Do not adjust)
"Set the P ICTURE MODE to NORMAL.
1. Receive a black a nd white sign al (colo ur of f).
2. Se le ct 2 .V/C f r om the SE RV ICE M ENU.
3. M odif y 2. WDR R and 3.W DR G da ta t o ad just t he white
balance ( high light ).
4. Press the ME NU key a nd m emor iz e th e s et va lue.
5. C ha nge th e c ontrast an d brig htn ess wi th th e r em ot e c ontro l
up & down fr om l o w– li ght t o h ig h– lig ht a nd c heck t hat the
tr acking of th e w h it e b alan ce is g oo d.
Ad ju st ment
of
SUB BRIGHT
Remote
control unit
5. BR IG HT 1. R ecei ve an y br o adc ast.
2. Se le ct 2 .V/C f rom the SE RV ICE M ENU.
3. Select 5.BRIGHT with the FUNCTI ON UP/DOWN key.
4. Set the initial setting value with the FUNCTION -/+ key.
5. If the br igh tn ess is n ot th e b est wi th the i n iti a l se tti ng va lue ,
make fine adjustment until you get the best brightness.
6. Pr ess the ME NU key a nd m emor iz e th e s et va lue.
Ad ju st ment
of
SUB CONT.
Remote
control unit
6.CO NT. 1. R ecei ve an y br o adc ast.
2. Se le ct 2 .V/C f rom the SE RV ICE M ENU.
3. Select 6.CONT with the FUNCTION UP/DOWN key.
4. Set the initial setting value with the FUNCTION - / + key.
5. If the con trast is n ot t he be st wi th t he i nitial se tti ng va lu e, ma ke
fineadjustment until you get the best contrast.
6. Pr ess the ME NU key a nd m emor iz e th e s et va lue.