Audio system
NO.of channels
OSD language
Multi-picture modes
AV stereo
Super woofer
Surrounding sound
Treble/bass boost
AUDIO
Left/right balancer
NICAM
Multi-audio modes
Tone adjuster
MTS/SAP
Auto-volume leveling
AV input
AV output
JIC
DVD terminal
S-video jack
Headphone socket
SCART socket
Digital curtain
Slow fading on & off
Semitransparent menu
Non-flshing channel changing
ZOOM
SOFTWARE
16:9 mode
Games
Calendar
Child-lock
Multi-functional lock
No-picture listening
Background light
Auto-timer on
CCD
V-CHIP
TDA9373
SF
PAL SECAM
B/G
218
ENG/THA
YES
YES
YES
YES
YES
YES
YES
YES
Y
Y
Y
Y
Y
Y
Y
Y
Y
Y
Y
Y
Y
Y
NO. FUNCTION
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
APPROVAL
NO. of built-in speakers
Audio output power(W)
Total power input
Voltage range
PARAMETER
Power frequency
Time of sleep timer(MINS)
Net weight(KG)
Gross weight(KG)
Net dimension(MM)
Packaged dimension(MM)
Quantity for 20' container
Quantity for 40' container
Quantiry for 40' high container
Acquired certificate
Suitable market
W
V
Hz
5
5W+5W+8W
140
150-250V
50HZ
42Kg
46Kg
810*530*600
3
Page 5
SAFETY PRECAUTIONS
5. SAFETY PRECAUTIONS
INPORTANT SAFETY NOTICE
These parts are identified by many electrical and mechanical parts in this chassis have
special safety-related characteristics.
It is essential that these special safety parts should be replaced with the same
components as recommended in this manual to prevent X-RADIATION, Shock, Fire, or
other Hazards.
Do not modify the original design without permission of the manufacturer.
General Guidance
An Isolation Transformer should always be used during the servicing of a receiver whose
chassis is not isolated from the AC power line. Use a transformer of adequate power
rating as this protects the technician from accidents that might result in personal injury
caused by electrical shocks.
It will also protect the receiver and it’s components from being damaged by accidental
shorts of the circuitry that might be inadvertently introduced during the service operation.
If any fuse (or Fusible Resistor) in this TV receiver is blown, replace it with a specified
one.
When replacing a high wattage resistor (Oxide Metal Film Resistor, over 1W), keep the
resistor 10mm away from PCB.
Keep wires away from high voltage or high temperature parts.
Due to the high vacuum and large surface area of the picture tube, extreme care should
be taken in handling the Picture Tube. Do not lift the Picture Tube by its Neck.
X-RAY Radiation
Warning:
The source of X-RAY RADIATION in this TV receiver is the High Voltage Section and the
Picture Tube.
For continued X-RAY RADIATION protection, the replacement tube must be of the same
type as specified in the Replacement Parts List.
Before returning the receiver to the customer,
Always perform an AC leakage current check on the exposed metallic parts of the
cabinet, such as antennas, terminals, etc., to make sure that the set is safe to operate
without any danger of electrical shock.
4
Page 6
Warning and Cautions
6Warning and Cautions
1. When you clean the TV set, please pull
out the power plug from AC outlet. Don't
clean the cabinet and the screen with
benzene, petrol and other chemicals.
2.
In order to prolong the using life of the
TV set, please place it on a ventilated
place.
4. To prevent the TV set from firing and
electric shock, don't
make the TV set rain
or moisture.
5. Don't open the back cover, otherwise it is
possible to damage the components in the
TV set and harm you.
3.
Don't place the
TV set in the
sunshine or near
heat source.
6. When the TV set isn't going to be used
for long time or it is in thunder and
lightening, please pull out the plug from AC
outlet and the antenna plug from the cover
of the TV set.
5
Page 7
Warning and Cautions
Explanation on the display tube
Generally, it is not needed to clean the tube surface. However, if necessary, its surface
can be cleaned with a dry cotton cloth after cutting off the power. Don’t use any cleanser.
If using hard cloth, the tube surface will be damaged.
CAUTION: Before servicing receivers covered by this service manual and its
supplements and addenda, read and follow the SAFETY PRECAUTIONS.
NOTE: If unforeseen circumstances create conflict between the following servicing
precautions and any of the safety precautions, always follow the safety precautions.
Remember : Safety First.
General Servicing Precautions
1. Always unplug the receiver AC power cord from the AC power source before:
a. Removing or reinstalling any component, circuit board module or any other
assembly of the receiver.
b. Disconnecting or reconnecting any receiver electrical plug or other electrical
connection.
c. Connecting a test substitute in parallel with an electrolytic capacitor in the
receiver.
CAUTION: A wrong substitution part or incorrect installation polarity of
electrolytic capacitors may result in an explosion hazard.
d. Discharging the picture tube anode.
2. Test high voltage only by measuring it with an appropriate high voltage meter or other
voltage-measuring device (DVM, FETVOM, etc.) equipped with a suitable high
voltage probe. Do not test high voltage by “drawing an arc”.
3. Discharge the picture tube anode only by (a) first connecting one end of an insulated
clip lead to the degaussing or kine aquadag grounding system shield at the point
where the picture tube socket ground lead is connected, and then (b) touch the other
end of the insulated clip lead to the picture tube anode button, using an insulating
handle to avoid personal contact with high voltage.
4. Do not spray chemicals on or near this receiver or any of its assemblies.
5. Unless specified otherwise in this service manual, clean electrical contacts only by
applying the following mixture to the contacts with a pipe cleaner, cotton-tipped stick
or comparable nonabrasive applicator; 10% (by volume) Acetone and 90% (by
volume) isopropyl alcohol (90%-99% strength)
CAUTION: This is a flammable mixture.
Unless specified otherwise in this service manual, lubrication of contacts is not
required.
6. Do not defeat any plug / socket B+ voltage interlocks with which receivers covered
6
Page 8
Warning and Cautions
by this service manual might be equipped.
7. Do not apply AC power to this instrument and/or any of its electrical assemblies
unless all solid-state device heat sinks are correctly installed.
8. Always connect the test receiver ground lead to the receiver chassis ground before
connecting the test receiver positive lead.
Always remove the test receiver ground lead last.
9. Use with this receiver only the test fixtures specified in this service manual.
CAUTION: Do not connect the test fixture ground strap to any heat sink in this
receiver.
Electrostatically Sensitive (ES) Devices
Some semiconductor (solid state) devices can be damaged easily by static electricity.
Such components are usually called Electrostatically Sensitive (ES) Devices. Examples
of typical ES devices are integrated circuits and some field effect transistors and
semiconductor “chip” components. The following techniques should be used to help
reduce the incidence of component damage caused by static electricity.
1. Immediately before handling any semiconductor component or semiconductorequipped assembly, drain off any electrostatic charge on your body by touching a
known earth ground. Alternatively, obtain and wear a commercially available
discharging wrist strap device, which should be removed to prevent potential shock
prior to applying power to the unit under test.
2. After removing an electrical assembly equipped with ES devices, place the
assembly on a conductive surface such as aluminum foil, to prevent electrostatic
charge buildup or exposure of the assembly.
3. Use only a grounded-tip soldering iron to solder or unsolder ES devices.
4. Use only an anti-static type folder removal device. Some solder removal devices not
classified as “anti-static” can generate electrical charges sufficient to damage ES
devices.
5. Do not use freon-propelled chemicals. These can generate electrical charges
sufficient to damage ES devices.
6. Do not remove a replacement ES device from its protective package until
immediately before you are ready to install it. (Most replacement ES devices are
packaged with leads electrically shorted together by conductive foam, aluminum foil
or comparable conductive material).
7. Immediately before removing the protective material from the leads of a
replacement ES device, touch the protective material to the chassis or circuit
assembly into which the device will be installed.
CAUTION: Be sure no power is applied to the chassis or circuit, and observe all other
safety precautions.
7
Page 9
Warning and Cautions
8. Minimize bodily motions when handling unpackaged replacement ES devices.
(Otherwise even some normally harmless motions such as mutual brushing of your
clothes’ fabric or lifting of your foot from a carpeted floor might generate static
electricity sufficient to damage an ES device.)
General Soldering Guidelines
1. Use a grounded-tip, low-wattage soldering iron and appropriate tip size and shape
that will maintain tip temperature within the range of 500 oF to 600 oF.
2. Use an appropriate gauge of RMA resin-core solder composed of 60 parts tin/40
parts lead.
3. Keep the soldering iron tip clean and well tinned.
4. Thoroughly clean the surfaces to be soldered. Use a mall wire bristle (0.5 inch, or
1.25cm) brush with a metal handle. Do not use freon-propelled spay-on cleaners.
5. Use the following unsoldering technique
a. Allow the soldering iron tip to reach normal temperature.(500 o F to 600o F)
b. Heating the component lead until the solder melts.
c. Quickly draw the melted solder with an anti-static, suction-type solder removal
device with solder braid.
CAUTION: Work quickly to avoid overheating the circuit board printed foil.
6. Use the following unsoldering technique
a. Allow the soldering iron tip to reach normal temperature.(500 o F to 600o F )
b. First, hold the soldering iron tip and solder the strand against the component lead
until the solder melts.
c. Quickly move the soldering iron tip to the junction of the component lead and the
printed circuit foil, and hold it there only until the solder flows onto and around
both the component lead and the foil.
CAUTION: Work quickly to avoid overheating the circuit board printed foil.
d. Closely inspect the solder area and remove any excess or splashed solder with a
small wire-bristle brush.
Remove /Replacement
Some chassis circuit boards have slotted holes (oblong) through which the IC leads are
inserted and then bent flat against the circuit foil. When holes are of slotted type, the
following technique should be used to remove and replace the IC. When working with
boards using the familiar round hole, use the standard technique as outlined .
Removal
Desolder and straighten each IC lead in one operation by gently prying up on the lead
with the soldering iron tip as the solder melts.
8
Page 10
Warning and Cautions
Draw away the melted solder with an anti-static suction-type solder removal device (or
with solder braid) before removing the IC.
Replacement
Carefully insert the replacement IC in the circuit board.
Carefully bend each IC lead against the circuit foil pad and solder it.
Clean the soldered areas with a small wire-bristle brush.(It is not necessary to reapply
acrylic coating to the areas).
Remove the defective transistor by clipping its leads as close as possible to the
component body.
Bend into a “U” shape the end of each of three leads remaining on the circuit board.
Bend into a “U” shape the replacement transistor leads.
Connect the replacement transistor leads to the corresponding leads extending from the
circuit board and crimp the “U” with long nose pliers to insure metal to metal contact then
solder each connection.
Power Output, Transistor Device
Removal/Replacement
Heat and remove all solder from around the transistor leads.
Remove the heat sink mounting screw (if so equipped).
Carefully remove the transistor from the heat sink of the circuit board.
Insert new transistor in the circuit board.
Solder each transistor lead, and clip off excess lead.
Replace heat sink.
Diode Removal/Replacement
Remove defective diode by clipping its leads as close as possible to diode body.
Bend the two remaining leads perpendicularly to the circuit board.
Observing diode polarity, wrap each lead of the new diode round the corresponding lead
on the circuit board.
Securely crimp each connection and solder it.
Inspect (on the circuit board copper side) the solder joints of the two “original” leads. If
they are not shiny, reheat them and if necessary, apply additional solder.
Fuse and Conventional Resistor
Removal/Replacement
9
Page 11
Warning and Cautions
1. Clip each fuse or resistor lead at top of the circuit board hollow stake.
2. Securely crimp the leads of replacement component around notch at stake top.
3. Solder the connections
CAUTION: Maintain original spacing between the replaced component and adjacent
components and the circuit board to prevent excessive component temperatures.
Circuit Board Foil Repair
Excessive heat applied to the copper foil of any printed circuit board will weaken the
adhesive that bonds foil to the circuit board causing the foil to separate from or “lift-off”
the board. The following guidelines and procedures should be followed whenever this
condition is encountered.
At IC Connections
To repair a defective copper pattern at IC connections use the following procedure to
install a jumper wire on the copper pattern side of the circuit board.(Use this technique
only on IC connections).
1. Carefully remove the damaged copper pattern with a sharp knife. (Remove only as
much copper as absolutely necessary).
2. Carefully scratch away the solder resist and acrylic coating (if used) from the end of
the remaining copper pattern.
3. Bend a small “U” in one end of a small gauge jumper wire and carefully crimp it
around the IC pin. Solder the IC connection.
4. Route the jumper wire along the path of the out-away copper pattern and let it
overlap the previously scraped end of the good copper pattern. Solder the
overlapped area and clip off any excess jumper wire.
At other connections
Use the following technique to repair the defective copper pattern at connections other
than IC Pins. This technique involves the installation of a jumper wire on the component
side of the circuit board.
1. Remove the defective copper pattern with a sharp knife.
Remove at least 1/4 inch of copper, to insure that a hazardous condition will not exist
if the jumper wire opens.
2. Trace along the copper pattern from both sides of the pattern break and locate the
nearest component that is directly connected to the affected copper pattern.
3. Connect insulated 20-gauge jumper wire from the lead of the nearest component on
one side of the pattern break to the lead of the nearest component on the other side.
Carefully crimp and solder the connections.
CAUTION: Be sure the insulated jumper wire is dressed so that it does not touch
components or sharp edges.
10
Page 12
Net Dimension
7 Net Dimension
790mm
525mm
590mm
11
Figure 1
Page 13
8Parts and Funcitions
Front and side panel of the TV set
1 .Fro n t Pa n e l
MENUP TV/AV
Remot e sensor:let The remo te controller aim he re the set can rece ive remote
control signal.
Power switch:Press the button to turn on the TV set . press the button again to turn
off the TV set.
Power indicator: the indicator lights in standby status ,the indicator lights in sleep
status . The indicato r glin ts when you use remote contro ller
Menu butto n
Progr am up/do w n button
Vo lu me up/down button
TV/AV
2.Rear Panel
And Side Board
.
Parts and Funcitions
VIDEO input
Left audio input
Right audio input
S-VHS input
VIDEO input/output
DVD component input
11
Antenna input
Audio input/output
A V IN 1
When using S terminal, please pull out video 1 input terminal
Figure 2
11
12
Page 14
9. Remote Controller Functions
Remote Controller Functions
MARK
FUNCTION DESCRIPTION
Program scan
Standby
SWAP
Mute
1
2
3
TV/AV
-VOL+
-CH+
TV/VIDEO SELECTION
VOLUME CONTROL
CHANNEL NUMBER UP/DOWN
PICTURE MENU
P
.
P
C
P
I
T
R
U
E
S
W
P
A
SOUND
TIME
FUNCTION
0-9
SOUND MENU
TIME MENU
FUNCTION MENU
ONE DIGIT SELECTION
-/--
MENU
MENU DISPLA Y
EXIT MENU DISPLAY
STEREO/NOMO SOUND SE LECT I ON
PICTURE MODE SELECTION
SOUND MODE SEL ECTION
TUNE MENU SELECTION
CHILDLOCK
Figure 3
13
Page 15
Program Diagram
10.ProgramDiagram
OPERATION MENU
OCT
TUNE
COLOR SYSTEM AU T O
SOUND SYSTEM B/G
BAND VHFL
SKIP OFF
PROG NO 19
SEARCH
FINE TUNE
AUTO SEARCH
6.Selecting color syste m
Usually this should be set in the Auto position. However if the colours displayed on
the scree n are incorrect you can manually select the correct co lour sy stem. When
you have f inished remember to turn it back to auto ag ain so that other pro g rams
will still work correctly. Use the CH+/- buttons to select COLOR SYSTEM then the
VOL+/- buttons to select a color system you need.. Press the EXIT button to save
the setting.
14
Page 16
Program Diagram
OPERATI ON M ENU
7.Program skip
The Program ski p featur e enables you to sk ip /h id e program s th at you do n o t w ish to
be displayed w hen usi ng th e C H + /- buttons. T h e se c h an n e ls w ill st i l l be di spl ayed by
di rect l y usi ng t he channel num ber but t ons on t he rem ote c o n tro l. th e
T o sk ip , press
CH+/- but t ons t o se lec t th e SKIP m enu, Pr ess the V O L+/ - but t ons t o t une t he skip
f eat ure on/ off. Pr ess the EX IT but t on t o save the setting .
8. Pr ogr am Number
The program num ber i s th e rem o te control channel num ber . Y ou can change th e
program num ber to see w hich channels are st ored w i t hout ex itin g th is m a in
menu. Pr ess t he CH +/ - but ton to se le c t PROG NO, Pr ess t he VOL+/- t o change
t he program num ber t hat you are adjusting.
9. Ba nd Sw itching (note: Thi s is a new item )
If you already know w hat band t he channel is on, t uning can speed up by
se lecting the correct band before going in to th e search menu. This feat u re
should only be used i f you underst and th e channels in your lo cal area.
Picture Adjustments
1 Contrast ( A dds dept h t o t he pictur e)
Pr ess t he CH+/- but t ons t o sel ect Contrast, th en
press th e V O L + /- b u tto n s to adjust t he Contrast l evel .
2 Bri ght ness (A dds sparkle and shine to the picture)
PIC T UR E
CONTRAST 89
BRIG HTNESS 66
COLO UR 50
SHA RPN ESS 50
TILT 08
IIIIIIIIIIIIIIIIIIIIIIIII..........
OCT
Pr ess t he CH+/- but t ons t o sel ect Brightness, then
press th e V O L + /- b u tto n s to adjust t he brightness
lev el.
3 Col our (A dds col our dept h)
Pr ess t he CH+/- but t ons t o sel ect Colour, then press t he V O L + /- but t ons t o
adjust th e C olour l evel .
4 Sharpness (A dds fine detail)
Pr ess t he CH+/- but t ons t o sel ect Sharpness, then press t he VOL+/- but tons t o
adjust th e Sharpness le v el.
Note: D o n o t tu rn th e sharpness up to high if th e rec e p tio n is poor or has l ots of
noi se as it w ill enhance t he fine g rain details.
15
Page 17
OPERATION M ENU
Sound Adjustments
Press th e m e n u b u tto n tw ice or press the Sound button on th e rem o te con trol,
to display th e Sound setting m enu.
1 Volum e (A djust the l oudness l evel )
SOUND
VOLUME 50
BASS 50
TR EBL E 50
BALANCE 0
SURROUND OFF
WOOFER ON
WOOFER VOL 50
IIIIIIIIIIIIIIIIIIIIIIIII..........
OCT
Pr ess t he C H + /- b u tto n s to sele ct Volum e,
th en pr ess the VOL+/- but tons to adjust th e
v o lu m e lev el.
2 Ba s s (Add lo w frequency depth)
Pr ess t he C H + /- b u tto n s to sele ct B ass, th en
press th e V O L + /- b u tto n s to adjust t he
v o lu m e lev el.
3 Tr eble ( Add hi gh f requency clarity)
Pr ess t he C H + /- b u tto n s to sele ct Treble, th en
press th e V O L + /- b u tto n s to adjust t he treb le
lev el.
4 Balance (S elects betw een the left and righ t
stereo channel l evels)
Pr ess t he C H + /- b u tto n s to sele ct Balance,
th en pr ess the VOL+/- but tons to adjust th e
balance lev el.
5 S urrou n d (E nh ances the stereo effect by
m aki ng t he sound appear w ider)
Pr ess t he C H + /- b u tto n s to sele ct
SURROUND, th e n press t he V O L+/- but t ons
to tu rn th is fea tu re on/off.
6.W oofer on/off
Press the CH+/- buttons to select
SURROUND, then press the VOL+/buttons to turn this woofer on/off.
7.Woofer volume adjustment
Press the CH+/- buttons to select
WOOFER VOL, then press the VOL+/buttons to adjust woofer volume.
16
Page 18
OPERATION MENU
Function Menu
1.B ackground (If th e sig n a l is very poor or t here is no
in pu t signal th e picture w ill m ute to black)
Pr ess t he C H + /- but t ons t o sel ect Background,
th en pr ess the VOL+/- b u tto n s to tu rn th is feat u re
on/off.
FUNCTION
BACKGROUND ON
BLACK STR ETCH ON
NOISE REDUCE OFF
FA D E ON
CHILDLOCK OFF
AV L OFF
SO FT CHANGE OFF
OCT
2.N oise R educe (P icture Noise & G rain reduction c irc u it.)
Pr ess t he C H + /- but t ons t o sel ect Noise Reduce, th en press t he VOL+/but t ons t o t ur n th is feature on/off.
4. Chi ld Lock (Enables th e TV front cont rol but t ons t o be lo ck ed )
Pr ess t he C H + /- b u tto n s to se lec t C h ild L o ck , t hen press th e VOL+/ but t ons t o t ur n t hi s feature on/off.
5. AV L (A ut om at i c Volum e Li mit control reduces effect of l arge vol um e
changes such as w hen the ads com e on) Press th e C H + /- b u tton s to select
AVL, th en p re ss th e VOL+/- buttons to tu rn th is featu re on/off.
6. B lack Stretch (A dds D eeper B l acks and i ncreases the contrast range)
Pr ess t he C H + /- but t ons t o sel ect Black Stretch, th e n press t he VOL+/- buttons
to tu rn th is fea tu re on/off.
Calender Menu
E n ter C a len d e r m e n u , press th e P+/P- to sel ect year, month, dat e, press th e VOL+/to cha n ge calender set up.
SOLA R 2008 1 20
LU N A R 2002 12 18
S M T W T F S
1 2 3 4
5 6 7 8 9 10 11
12 13 14 15 16 17 18
19 20 21 22 23 24 25
26 27 28 29 30 31
17
Page 19
MULT I FUNCT ION TIM ER
Multi Function Tim er
The TV set has in built a c om p reh en siv e tim er
th at has Five basic funct i ons
1.Clock
2 .O n tim er so th a t the TV set can be pr ogram m ed
to tu rn o n at a certain t im e
3.O ff tim e r that allow th e TV set to tu rn off at a
preset tim e
4.Sleep t im er to allow t he T V se t to tu rn o ff after
TIM E
CLOCK --:-ON TIM E --: -ON-PROG 1
OFF TIM E --:-SLEEP TI MER --: -REM IND TIM E --:-REM IND PRO G 1
COUN T 00001:22
OCT
10 ~ 180 minutes
5. Program r em ind t i m er , that displays an onscreen rem inder prom pt, when a program on a
di fferent channel i s due to star t.
Note: The clock w ill o nly wo rk if th e T V set if le ft tu rn e d on or in standby.
W hen the set is disconnect from th e p ow er supply or i s turned of f by t he
main pow er sw itch o n th e fro nt panel, th e clock lo o ses pow er and w il l
need to be re se t w h e n th e pow er is reconnected.
18
Page 20
MULTI FU NCTIO N TIM ER
to a d ju st th e am ount of t im e before th e TV se t w ill a u to m atic ally
tu rn o ff. Each tim e th e V O L+ but t on i s pressed the sleep tim e will in c re ases by 10
minutes. The m axi m um sl eep tim e i s 180 m i nut es.
5. Remind Tim e
Press th e C H + /- buttons to select R E M IN D TIM E, then press the VOL+/- but t ons t o
adjust th e H ours
Press th e C H - Button to sele ct min utes an d th e VOL + /- to a d ju st th e minutes.
Press th e C H - Button to sele ct REM IND-PROG and the VOL +/- to select the TV
channel th a t the T V set w ill au to m atically rem ind you to t ur n t o w hi l e wat ching
another channel.
6.C ount
The funct i on i s used for di splay t he TV s et used for all tim e.
OCT
Program Number E xchange
This fe ature enables TV program s that m ay
be on a wrong TV channel num ber to be
sw apped/exchanged. This feature is very
EX CH A N G E
P ROGRAM 1 1
P ROGRAM 2 1
EX CH A N G E
usef ul w hen A utom atic Search Tuni ng has
been used, to re allo c a te t he found program s
to th e co rrect channel num ber s.
Pr ess t he Menu butt on 6 tim es unt i l t he exchange m enu i s displayed.
Pr ess t he CH+/- until program 1 is selected. Use th e VOL+/- buttons to
select the channel num ber to be sw apped. (I. E if you wi sh to exchange
Cha nnel 2 and 4 PR O G RA M 1 shoul d = 2)
Pr ess t he CH+/- until program 2 i s selected. Use the V O L+/ - but tons to
select the channel num ber to be sw apped. (I. E if you wi sh to exchange
Cha nnel 2 And 4 PRO G RA M 2 shoul d = 4)
Pr ess t he CH+/- until EXCHANGE is sel ected. Pr ess th e VOL+ button to
enable t he exchange.
19
Page 21
GENERAL OPERATION
1.C hannel Changi ng (218 possibl e channels)
Use either th e C H + /- buttons on th e rem o te o r th e f ront of t he TV s et to change t he
channels.
Or
D irect ly ent er t he channel num ber w i t h t he num eri c keypad on th e rem o te co n tro l.
To sel ect channel num ber s from 10 ~ 99 press [-/--] button an d enter th e tw o digit
channel num ber. To sel ect channel num ber s from 100 ~ 218 pr ess [-/ --] button
tw ice and enter the 3 digit channel num ber.
2.Volume Adjustment
Press th e V O L + /- b u tto n s on th e re m o te o r th e fro n t of th e TV se t to ad ju st th e
vol um e le v el. The range i s 0~99. W hen the Vol um e but t ons are pressed the volum e
l evel i s di spl ayed autom atically on th e TV scr een.
3.Standby
U sin g th e rem ote cont rol t he TV s et can be pl aced i nt o standby mode. Standby
m ode m ust be used fo r th e Tim er features to operate correctly. A re d standby lig h t
w ill g low on th e TV front panel when th e T V set is p la ce d into standby. To tu rn
th e TV set back on agai n pr ess st andby but t on on t he rem o te control again. It will
take a few seconds before a picture w ill be displayed.
4.Mute
Press th e m u te button on th e re m o te co n tro l to mute th e TV set s sound. Pressing
th e M ute again w ill tu rn th e sound back on again.
5.Preset Picture M odes
Our engineers have desi gned i n 5 com m onl y used pi ct ure set ti ngs to allow fast
pi ct ure lev el selectio n depending on w h a t ty p e o f TV program is show ing. Each
m ode i s se lec te d in tu rn by pressi ng t he "P STD " button on th e rem o te co n tro l.
The 5 modes are
Listen- This is a new feature th at blacks out th e TV screen when listening to
music onl y channel s
Soft - D esigned for night tim e l ow l i ght vi ew i ng
Standard - D esi gned f or room s th at have good all round l i ght i ng
Rich - D esigned fo r room s w i th hi gh am bi ent l i ght i ng such as daytim e sport .
User- A s pare setting th at can b e ad ju sted t o personal tastes
U sin g th e PICT URE adj ust m ent di splay m enu all 5 m odes can independently
adjus ted.
20
Page 22
GENERAL OPERATION
6.Pr es et Sound Modes
Ou r engi neer s have designed in 4 com m only used sound mo des to allo w th e
best possi bl e sound t o be selected quickl y. Each m ode i s sel ected in tu rn b y
pressing t he "S STD" but ton on th e rem o te control.
The 4 m odes are
Speech- D esi gned to red u ce th e bass and tre b le w hi ch enhances th e voice fo r
Ne ws program s
Theatre- Enables extra bass and treble to enhance t he m ovie exp erience
M usi c- Adjust the sound to best suit m usic program s
U ser - A s pa r e settin g th at can be adj ust t o per sonal t astes
U sing th e SOUND adjustm ent display m enu all 4 m odes can independent l y adj ust ed
7. Recal l ( O n-screen Display)
The Call butt on on the rem ote control allow s the onscreen menu to be
displayed, show ing th e channel num bers and col our syst em .
8. Program Scan (A ut om at i call y in c rem en ts/scan s th e channels and displays
each channel fo r a sh ort tim e)T he SC A N butt on on t he rem o te control turns
on/off th e scan f eature.
9. Zoom (Changes th e p ictu re si ze form at)
Each tim e the ZOOM b u tto n is pressed th e p ictu re si ze w il l change. There
are th e foll o w ing size options.
Normal - Used fo r st andard 4: 3 picture program s
E nlargem ent - Z o o m s th e p ictu re in to magnify sm aller im ages.
10.Sw ap (Toggles betw een the last channel view and the current channel)
Each tim e th e SW AP butt on i s pressed the last channel view i s di spl ayed.
11.AV input sel ect i on
Each tim e the TV/AV but t on i s press t he inp u ts selectio n will cycle betw een
TV- AV1- AV2- SVHS- DVD - TV.
No te s: I.AV1 & SV HS share the sam e AV 1 audio inputs.
.In AV m odes the RECALL stat us di spl ay will o n ly di spl ay t he colou r
system .
12.Lock
Pr ess t he LOCK b u tto n to sele ct Chi l dl ock on/ off.
21
Page 23
Maintenance Service and Trouble Shooting
11. Maintenance Service and Trouble Shooting
a. TROUBLESHOOTING PROCESS
Grating off
Check +B
Abnormal Normal
Disconnect R214 to
check main voltage
Normal
Abnormal None
Check TDA9373
voltage
Check for short between
output voltage and ground
Check for 300V voltage
Check N801 for
peripheral circuit
Check R415, R505
and R526
Check V403, T401
Check V402
Check pin 33 of
N201 for output
Check lamp filament,
release and grating voltages
Check CRT
cathode voltage
Check N201 for
signal output
Check TDA6107Q
and peripheral circuit
R, G and B
22
Page 24
d
Maintenance Service and Trouble Shooting
Horizontal bright line
Check pin 21 and 22 of N201 for curve output
None Yes
Check R228 and C227
Abnormal Normal
Check N201
Check R413 and R408
Check T444
Check 16V and 47V
voltage
Check N301 an
peripheral circuit
Disabled remote control
Abnormal Normal
Check all pins of V801for voltage
Check receiver voltage
Check pin 61 of
N201 voltage
Check RR230 and C234
Check VD806 for
voltage output
Check receiver
Check N201
23
Page 25
Pincushion distortion
Maintenance Service and Trouble Shooting
Enter factory mode and adjust
5EWP to see if picture changes
None Yes
Check pin 20 of N201for voltage
and ground resistance
Check
V401 and DZ401
Check pin 12 N301 for voltage
and ground resistance
Check C416
Check and replace
N201 and N301
Check and replace
VD404A andVD404B
24
Page 26
Maintenance Service and Trouble Shooting
TV program sound off
Yes
Check pin 7 of N201 for
None Yes
Yes None
noise suppression
No
Check N20144for
sound signal output
Check and replace N201
Check N70135
for sound signal output
Check N701 1518
for sound signal output
None Yes
Check and
replace N701
Check N601 and peripheral
Press mute button, or check
and replace N201
Check V213, R243,
C246 and C706
circuit components
25
Page 27
Maintenance Service and Trouble Shooting
b. Troubleshooting guide
To assist in location possible faults use help guide below
BREAKDOWN PHENOMENON
PICTURE
Picture with snowNoise
Double or Triple Image
Disturb
No PictureNo sound
SOUND
Normal
Noise
No soundNormal
The aerial direction and connection
This is called ghosting which can be minimized with
an outside aerial, and good quality cable and
terminations. Altering the aerial direction can also
minimize this effect.
Electrical interference which can be caused by cars,
motorbikes etc, Fluorescent lamps and dirty
insulators on overhead power cables.
Volume Sound mute
Ensure that the power supply is connected to
the TV set and turned on. Also ensure that the
TV set is not in "Listen Mode" or that the
brightness and contrast are not turned down.
CHECKING
.
Adjust colour control
No colour Normal volume
Adjust channel again
Scramble
Colour Spot
Note:
1.If the fault can not be repaired using the above guide consult with your local authorized service
center.
2.The TV set must only be repaired by a qualified registered service person. Never attempt to
remove the back cover as the TV set has dangerous voltages in side that may cause a fatally or fire.
3. The cabinet may produce the occasional "snapping sound" This is normal and caused by the
materials in the cabinet expanding with room temperature changes.
Normal or Weak Volume
Normal volume
Colour Purity fault which can be caused by moving the
TV set, placing magnets near the TV screen or turning
on/off house hold appliances such as vacuum cleaners
near the TV set. Turn the TV off with the mains power
switch for 15 minutes. When the power is turn on again
the TV set will automatically degauss the picture. In
server cases leave the TV set turned off over night.
NOTE:This diagram is only for reference and subject to
28
Page 30
Circuit Diagram
c.
PCB Diagram
Figure 6
29
Page 31
Circuit Explanation
13. Circuit Explanation
The UOC module comprised of Philip super advanced CMOS chip TDA9373 is used for model
34F9B-T color TV pictures and text. This product has I2C bus-mastering digital control system and
DVD component terminals (or SCART terminal) for auto sound identification, independent woofer
volume control, English and Russian picture texts, treble and bass tone increase, image and sound
mode for individual preference, picture size zooming and 218 channel storage.
I. Electrical circuits and integrated circuits of 34F9B-T TV receiver
1.1 Electrical circuits
Electric circuits of the 34F9B-T TV receiver are comprised of the following sections:
1.1.1 Microprocessor and signal processor: comprised of super single chip integrated circuit
N201(TDA9373), storage N202 (KS24C08).
1.1.2 Sound processing and amplifying: comprised of integrated circuit N701 (TDA9860) for
sound tone processing and integrated circuits N601 and N610 (TDA7297) for sound
amplifying.
1.1.3 Integrated circuit for line and field scan output: comprised of integrated circuit N301
(TDA8350Q) for field output, V403 (2SD1887YD) for line output tube and T444
(BSC29-0130D) line output transformer.
1.1.4 Video frequency amplifying: comprised of integrated circuit N501 (TDA6107Q)
1.1.5 Power supply control: comprised of switch transformer T801 (BCK-100-02), power
integrated circuit N801(KA5Q1265RF-YDTU) and secondary power integrated circuit N804
(KA7630).
1.2 Main integrated circuits:
1.2.1 TDA9373 Microprocessor / picture intermediate frequency / sound intermediate
frequency / video processing / line field scanning / color decoding / text
1.2.2 TDA9860 Multi- function TV stereo sound tone processing integrated circuit
1.2.3 TDA8350Q Field output integrated circuit
1.2.4 TDA6107Q Video amplifying integrated circuit
1.2.5 TDA7297 Sound amplifying integrated circuit
1.2.6 KA5Q1265RF-YDTU Power integrated circuit
30
Page 32
Circuit Explanation
1.2.7 KA7630 Secondary power integrated circuit
2 Electric circuit analyses
2.1 Super single chip integrated circuit TDA9373
As a super large-scale decoding and microprocessing integrated circuit, TDA9373 is comprised of a
microprocessor, picture image intermediate frequency amplification, sound intermediate frequency
amplification, line and field scanning, dwarf signal processing, color decoding, sound filtering and
auto identification, luminance separation, high voltage tracking and over voltage protection. It
functions for I
2
C bus-mastering and automatic adjustment for transmeridional correction and dark
balance.
Table 1 lists the pin function and test data of TDA9373 as the reference for maintenance.
The data is to be tested under the mode of 49.75MHz, PAL B/G and cylindrical color card muting,
using a model FLUKE 79
instrument.
Table 1
Resistance to Ground
Pin Function
Working
voltage
V
Forward Test Back Test
R
1. STANDBY 0 36K 29K
2. SCL 3.5 15K 15K
3. SDA 3.2 15K 15K
4. VT 3.0 20K 20K
5. KEY 3.4 36K 30K
6. SYSTEM 4.4 15K 15K
7. MUTE 5.1 15K 15K
8. GND.MAG 0 Infinity 2.9M
9. VSS C/P 0 0 0
10. BAND 3.3 14.5K 14K
11. BAND 0 14.5K 14K
12. VSSA 0 0 0
13. SEC.PLL 2.3 6.4M 4.3M
14. VP2 7.8 18K 18K
15. DECD/G 5.0 31.9K 32K
16. PH2.LF 2.9 6.4M 4.2M
17. PH1.LF 3.9 6.4M 4.2M
18. GND3 0 0 0
19. DEC.BG 4.0 39.8K 40K
20. EWD 0.7 63K 63K
21. V.DRB 2.4 6.0M 4.0M
22. V.BRA 2.4 6.0M 4.0M
23. IF.IN1 1.9 37.5K 38K
24. IF.IN2 1.9 37.5K 38K
25. I.REF 3.85 38.8K 38.8K
26. V.S.C. 3.8 6.3M 4.6M
27. TUNER.AGC 1.7 4.9K 4.9K
28. AU.DEEM 3.2 6.1M 3.6M
31
Page 33
Circuit Explanation
29. DECS.DEM 2.4 5.9M 3.6M
30. GND2 0 0 0
31. SND.PLL 2.4 6.3M 4.7M
32. AVL 0 6.2M 3.8M
33. H.OUT 0.6 21K 21K
34. F.B.L.SO 0.3 6.4M 4.4M
35. AUO.EXT 0 0 0
36. EHTO 1.7 21.8K 22K
37. PLL.IF 2.4 6.4M 4.6M
38. IF.VO/SVO 3.3 4.3M 4.6M
39. VP1 7.8 18K 18K
40. CVPS.INT 3.9 5.4M 4.1M
41. GND1 0 0 0
42. CVBS/Y 3.3 6.2M 4.0M
43. CHROMA 1.5 83K 83K
44. AUD.OUT 3.4 6.4M 4.8M
45.
INSS.W2
BL
2.1 0.86K 0.86K
46. R2/V.IN 2.5 6.3M 4.5M
47. G2/Y.IN 2.5 6.3M 4.5M
48. B2/U.IN 2.5 6.3M 4.5M
49. BCL.IN 1.5 216K 239K
50. BLK.IN 4.9 28K 28K
51. R.OUT 2.8 7.46K 7.5K
52. G.OUT 2.8 7.48K 7.5K
53. B.OUT 2.9 7.5K 7.5K
54. VDD.A 3.3 32K 26K
55. VPE 0 0 0
56. VDD.C 3.3 32K 26.5K
57. OSC.GND 0 14 13
58. XTAL.IN 1.8 3.0M 2.7M
59. XTAL.OUT 1.7 0.5M 0.54M
60. RESET 0 0 0
61. VDDP 3.4 32K 26.6K
62. AV1/AV2 5.1 15K 15K
63. AV/SVHS 5.1 15K 15K
64. INT.REM 5.0 41K 40.6K
2.3 Analysis of common passage circuits
Having been received by antenna or fed by cable TV into the antenna input terminal of HF tuner
TU101
TECC7949, HF TV signals pass through tuning for station selection, HF amplification and
frequency mixing inside the HF tuner and then, a 38MHz IF picture signal and 31.5MHz IF sound
signal will be transmitted from the IF terminal of TU 101 and be fed directly into (1) of the pre-IF
amplification thick-film circuit N101 (M9911A), where the signals will be amplified to compensate for
the insertion loss of the sound surface filter.
The sound surface filter SF101
K6264K adopts single-terminal or double-terminal input according to
different system choices. The single-terminal or double-terminal input are controlled by the (6) of
N201 via V101
BC548C: D/K, B/G and I signals will be input in a single channel and M signals in
double channels. The sound surface filter K6264K is a wide range filter for single channel input,
suitable for D/K, B/G and I sound signal; and is a narrow range filter for double-channel input,
32
Page 34
Circuit Explanation
suitable for M sound signal. The IF signals which have passed through sound carrier deep trap by
sound surface filter will be sent to the (23) and (24) of N201
be sent out from the (27) of N201
TDA9373 under the control of I2C bus for the gain control of HF
TDA9373 . HF amplification AGC will
tuner.
2.4 Analysis of signal trap option switch circuit
Video color signals will be sent out from (38) of N201
TDA9373and emit and followed by triodes
V208 and
V209, and then, divided into sub-flows which are fed into the wave traps Z201~Z204 respectively. All
TV signals will be selected and pass through V210 and V211, which are rejector triodesand serve the
function of switches here. When the 6 pins of N201(TDA9373) export high level with sound below
4.5M, V211 will break over and the signals will pass through the wave traps Z201~Z202; and when
the 6 pins send out low level with sound of 4.5M, V211 will stop and V210 break over, and the signals
will go through the wave traps Z203~Z204. Video signals will be produced after all TV signals are
trapped by the wave trap, and then, one sub-flow will go through R255
430and R256470
for signal adjustment amplitude and enter into (40) of N201TDA9373, and another sub-flow will,
after emit and followed by a triode V212, serve as AV output.
Both the video signal in AV signals and the Y signal in S terminal signals will be selected and passed
through by N702
signal of S terminal will be fed into the (43) of N201
and the Y signal of S terminal will be selected and passed through by N702
control of the (62) and (63) of N201
The DVD component terminal Y, U and V signals will be coupled by the capacitors C001
HEF4053BP, and will then be fed into the (42) of N201TDA9373; and the C
TDA9373 . Both the AV1 and AV2 video signals
HEF4053BP under the
TDA9373.
10u ,C006
10uand C00510uand fed into the (47), (48) and (49) of N201TDA9373respectively.
2.5 Analysis of sound tone processing circuit
The sound tone processing circuit is comprised of an integrated circuit N701
TDA9860and
peripheral components. TDA9860 is a multi-function TV sound tone processing integrated circuit of Hi-Fi
grade, inside which treble and bass frequency division processing, stereo processing and encircling
sound processing are made.
The audio signals sent out by the (44) of N201, after emit and followed by V213 and passing through
a coupling capacitor C706
N701
TDA9860respectively. Meanwhile, the audio signals from the left and right channels of AV1
terminal will be put into the (1) and (32) of N701
224 , will be divided into two sub-flows which enter into the (3) and (5) of
TDA9860 . The audio signals of S terminal and AV1
share the same sub-flow. The audio signals from the left and right channels of AV2 terminal will be
put into the (28) and (30) of N701
TDA9860. The audio signals of DVD component terminal and
AV2 share the same sub-flow.
As for TV or AV audio signals that have been selected and go through inside N701 (TDA9860) without
sound tone processing, the independent audio signal of left and right channels and exported directly
33
Page 35
Circuit Explanation
from (13) and (20) will be directly fed into the (12) of woofer amplification integrated circuit N610
(TDA7297); and, as for the audio signals that have gone through sound tone processing , the audio
signals exported from the (18) and (15) will be directly fed into the (12) and (4) of the sound
amplifying integrated circuit N601
TDA7297 . The external capacitors C717 562 and C714 562
of the (19) and (14) of N701TDA9860are used as the treble control capacitors for left and right
channels. The (31) of N701
TDA9860is a woofer control switch.
Table 3 lists the pin function and test data of TDA9860 as the reference for maintenance. The data is
tested under the mode of 49.75MHz
PAL D/K and cylindrical color card, using a model FLUKE 79
instrument.
Table 3
Resistance to Ground R
Forward Test
Back
Tes t
Pin Function
Working
Voltage
V
1 Pre-AV audio input of left channel 4.0 4.6M 3.1M
2 D-COIL 0.1 6.9M 4.9M
3 Interior audio input 4.0 4.7M 3.1M
4 Decoupling filter of power supply 7.9 9.1K 9.1K
5 Interior audio input 4.0 4.6M 3.1M
6 8V Power supply 8.0 2.8K 2.8K
7 AV audio output from right channel 4.0 6.5M 4.3M
8 Ground 0 0 0
9 Audio output from right channel 4.0 10.8K 10.8K
10 Audio input of right channel 4.0 4.6M 3.1M
11 Connecting terminal of bass control
4.0 4.6M 3.1M
capacitor
12 Connecting terminal of bass control
4.0 4.7M 3.1M
capacitor
13 Woofer frequency signal (L) 3.9 6.6M 3.9M~
14 Connecting terminal of treble control
4.0 6.2M 4.2M
capacitor
15 Audio output, right channel 4.0 8.8K 8.8K
16 Clock line of I2C bus 4.4 19K 17.9K
17 Data line of I2C bus 4.5 19K 18.0K
18 Audio output, left channel 4.0 8.9K 8.9K
19 Connecting terminal of treble control
4.0 6.2M 4.3M
capacitor
20 Woofer frequency signal (R) 3.9 6.5M 3.9M
21 Connecting terminal of bass control
4.0 4.6M 3.2M
capacitor
22 Connecting terminal of bass control
4.0 4.6M 3.2M
capacitor
23 Audio input of left channel 4.0 4.6M 3.2M
24 Audio output from left channel 4.0 10.8K 10.8K
25 Ground 0 0 0
26 AV audio output from left channel 4.0 6.5M 4.3M
27 Connecting terminal of analog. stereo
4.0 4.6M 3.2M
capacitor
28 Post- AV audio input of left channel 4.0 4.6M 3.2M
29 Connecting terminal of analog. stereo
4.0 4.6M 3.2M
capacitor
34
Page 36
30 Post-AV audio input of right channel 4.0 4.6M 3.2M
31 Woofer control 4.4 6.9M 4.8M
32 Pre-AV audio input of right channel 4.0 4.6M 3.2M
2.6 Analysis of sound amplifying circuit
The sound amplifying circuit is comprised of an integrated circuit TDA7297 and peripheral
components. TDA7297 is a double-channel stereo sound amplifying circuit featuring MUTE and
POWER functions, with power output 15+15W. TDA7297 has a BTL sound output manner with no
Circuit Explanation
coupling capacitor in its output circuit, which has a wide range of power supply
6V18Vand the
functions of short circuit protection and over-load protection.
(18) and (15) of the sound tone processing circuit N701 send out the sound signal for left and right
sound channels, which will be adjusted by R604, R603 and 607, R606 respectively , and then
coupled and fed into the (4) and (12) of the sound amplifying integrated circuit N601 via C601 and
C605, and , after being amplified, sent out from the (1), (2) and (14), (15) in positive and negative to
directly drive speakers for sound.
Woofer amplification is also comprised of the integrated circuit TDA7297 and peripheral components.
The sound signals from left and right channels that have not passed through sound tone processing,
will be coupled and fed into the (12) of N610 via C611, which, after being amplified, will be sent out
as positive and negative to directly drive speakers for sound.
Table 4 lists the pin functions and test data of TDA7297as the reference for maintenance. The data is
to be tested under the mode of 49.75MHz
79
instrument.
PAL D/K and cylindrical color card, using a model FLUKE
Table 4
Resistance to Ground R
Forward Test
Back
Tes t
Pin Function
Working
Voltage
V
1 Sound output from right channel 8.0 12.8K 12.7K
2 Sound output from right channel 8.0 12.8K 12.8K
3 15V Power supply 16.0 ~ 0.94M
4 Audio signal input of right channel 1.5 86.2K 86.6K
5 Blank pin 0 ~ ~
6 MUTE signal input 5.1 108.8K 107.6K
7 POWER signal input 5.1 5.6K 5.6K
8 Ground 0 0 0
9 Ground 0 0 0
10 Blank pin 0 ~ ~
11 Blank pin 0 ~ ~
12 Audio signal input of left channel 1.5 86.3K 86.5K
13 15V Power supply 16.0 ~ 0.94M
14 Sound output from left channel 8.2 12.7K 12.7K
15 Sound output from left channel 8.2 12.7K 12.7K
Table 5 lists the pin functions and test data of woofer TDA7297as the reference for maintenance.
35
Page 37
The data is to be tested under the mode of 49.75MHzPAL D/K and cylindrical color card, using a
Circuit Explanation
model FLUKE 79
instrument.
Table 5
Resistance to Ground R
Forward Test
Back
Tes t
Pin Function
Working
Voltage
V
1 Sound output from right channel 0 12.8K 12.7K
2 Sound output from right channel 0 12.8K 12.8K
3 15V Power supply 16.0 ~ 0.94M
4 Audio signal input of right channel 0 86.2K 86.6K
5 Blank pin 0 ~ ~
6 Bass signal input 4.4 108.8K 107.6K
7 POWER signal input 5.1 5.6K 5.6K
8 Ground 0 0 0
9 Ground 0 0 0
10 Blank pin 0 ~ ~
11 Blank pin 0 ~ ~
12 Audio signal input of left channel 0.7 86.3K 86.5K
13 15V Power supply 16.0 ~ 0.94M
14 Sound output from left channel 8.0 12.7K 12.7K
15 Sound output from left channel 8.0 12.7K 12.7K
2.7 Analysis of field output circuit
Field sync signals separated from the mixed sync signals trigger the field frequency division system.
Once a certain sum of field sync pulse signals have been detected, the field frequency division
system will start in action. Of the field sync pulse signals which are obtained from frequency division,
one sub-flow will be fed into a sample pulse generator to, together with line feedback signal, produce
sample pulses necessary for the circuit.
Another sub-flow will be sent to field saw-tooth wave generator. The field frequency saw-tooth wave
that has undergone geometric processing will be sent from the (21) and (22) of N201 to the (1) and (2)
of the field output N301. The external resistor R228
current to field saw-tooth wave generator , and the external capacitor C227
39Kof the (25) of N201will supply reference
104of the (26) serves
as the capacitor for field saw-tooth wave.
Field output integrated circuit N301 is a full bridge type current driving output circuit of with a bridge
type output manner, and field deflection coil is directly connected to the middle of output amplifier.
The positive and negative saw-tooth signals sent out from the (21) and (22) of N201will enter into the
(1) and (2) of N301 symmetrically, which, after being rectified and amplified by TDA8350Q, will be
sent out from the (9) and (5).
R301 (3K
produced when field scan current flows through a hunt resistor of R302(1.5
) will transform input current into voltage, which will be compared with the voltage
) and R303(1.5), and
the result thus obtained will be a feedback voltage for TDA8350Q, therefore, field output current size
can be changed by changing R301. TDA8350Q has double power supplies, and the line return stroke
pulses sent out by the line output transformer T444 will be rectified and filtered to supply power to
36
Page 38
Circuit Explanation
both the forward and return strokes of TDA8350Q , the two power supplies being +16.5V and +46V
respectively.
Table 6 lists the pin functions and test data of TDA8350Q as the reference for maintenance. The data
is to be tested under the mode of 49.75MHz
FLUKE 79
instrument.
PAL D/K and cylindrical color card, using a model
Table 6
Resistance to Ground R
Forward
Tes t
Back
Tes t
Pin Function
1 Field pumping signal input in positive
Working
Voltage
V
2.4 67.0K 67.3K
phase VDP
2 Field pumping signal input in negative
2.4 69.9K 70.3K
phase VDN
3 FEEDBACK 8.3 5.9K 5.9K
4 SUPPLY VOLTAGE 16.9 6.4M 2.4M
5 OUTPUT VOLTAGE B 8.2 6.4K 6.1K
6 Blank pin 0 ~ ~
7 Ground 0 0 0
8 FLYBACK SUPPLY VOLTAGE 48.8 32.5K 25.5K
9 OUTPUT VOLTAGE A 8.6 5.9K 6.1K
10 Blank pin 0.9 ~ 4.1M
11 Transmeridional correction signal
11.1 10.4K 10.1K
output
12 Transmeridional correction signal
0.73 62.5K 62.9K
input
13 Ground 0 0 0
2.8 Analysis of line sync and scan output circuit
As the line oscillation circuit is inside N201(TDA9373), no external line oscillation components is
needed and the oscillation frequency is under the control of PH-1 detector. A flow of luminance
signals including mixed syne signals is sent to a syne separation circuit therein, which separate line
and field syne pulse signals, among them, the line syne pulse signals are sent to PH-1 detector. The
PH-1 detector functions to synchronize the line oscillation frequency with the frequency of input
signals.
C221(472)
R226(15K) and C222(1u) connected to N201(17) are PH-1phase-locked loop filters.
The line oscillation signals that have been corrected by PH-1 detector will be sent to PH-2 detector,
which functions to stabilize and control the phase of line drive pulse output for ensuring that the line
linearity and center remain unchanged.
The external capacitor C218(222) of (16) is a filter capacitor for PH-2 detector. Line pumping signals
are sent out by the (33) of N201 and fed into a line driving triode V402
being amplified by a triode V403
2SD1887 switch, drive line deflection coil to produce magnetic field
KSC2331, and then, after
to control an electronic beam for horizontal scanning.
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Circuit Explanation
C414, C415 and C427 are the capacitors for line return stroke, C406 is the line S correction capacitor,
and L402 is the linear inductance for line. E-W geometric correction signals are sent out by the (20)
of N201 and fed into the (12) of N301, which, after being rectified, will be sent out from the (11) of
N301 and, after being amplified by a triode V401(KSA614Y) and waveshaped by C403 and L401, put
into line scanning circuit for a geometric correction in transmeridional direction.
Both VD404A and VD404B are modulating damper diodes, and T444 is a line output transformer. VD202,
R275, R276, R259 and C256 constitute a HV tracking circuit to compensate HV variation caused by
variation of luminance, hence an automatic correction of change of picture geometric sizes along with
HV variation. R419, R249, VD201, R248 and C250 constitute a beam limit circuit.
Line return stroke pulses sent out by the (9) and (8) of line output transformer T444 will be rectified
and filtered to produce DC voltage +16.5V and +46V, which are then fed into the (4) and (8) of
N301for supply power to the forward and return strokes of field output integrated circuit, , and, the
voltage+16.5V will then be regulated by N401
supply to such dwarf signal processing circuits as HF tuner TU101
SF101
K6264Kand pre-IF amplifier N101M9911A.
KA7812Ato obtain a DC voltage +12V for power
TECC7949 , sound surface filter
(7) sends out a heater voltage of 6.3Vrms ; (1) provides line sync signal to N201
TDA9373 ; and the
line return stroke pulse sent out by the (5) is rectified and filtered to obtain a DC voltage +180V for
power supply to video amplification circuit.
2.9 Analysis of video amplification circuit
Video amplification circuit is comprised of an integrated circuit N501
TDA6107Qand peripheral
components. R, G and B signals coming from the (51), (52) and (53) of N201(TDA9373)are sent to the
(2), (3) and (1) of N501 respectively. TDA6107Q , an integrated video amplification output circuit ,
contains three independent video amplifiers which amplify the input R, G and B, three basic color
signals, which are fed into the cathode of picture tube by (7), (8) and (9).
The (5) of N501 checks the dark balance output, and the check result thus obtained will be sent to
the (50) of N201 for adjusting the dark balance of picture. White balance will be adjusted by sending
out R, G and B, three basic color signals, under the control of I
2
C bus. C5044.7u, R50410M
and VD501ERC24-06constitute a luminous spot killing circuit of cut-off type.
Table 7 lists the pin functions and test data of TDA6170Q as the reference for maintenance. The data
is to be tested under the mode of 49.75MHz
FLUKE 79
instrument.
PAL B/G and cylindrical color card, using a model
Table 7
Resistance to Ground R
Forward Test
Back
Tes t
Pin Function
Working
Voltage
V
1 B input 2.9 7.6K 7.4K
2 R input 2.8 7.6K 7.5K
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Circuit Explanation
3 G input 2.8 7.6K 7.4K
4 Ground 0 0 0
5 Dark current detection output 4.9 3.1M 2.7M
6 Power supply 182.6 34.2K 28.2K
7 R cathode output 97.6 1.4M 2.6M
8 G cathode output 100.1 1.4M 2.6M
9 B cathode output 93.4 1.4M 2.6M
2.10 Analysis of power switch circuit
A typical self-excited pulse power switch has been chosen for this TV receiver. When the power
switch is in the ON position, the voltage from AC 220 V power grid will be rectified by a rectifying tube
VD810 to produce a pulse voltage , which will be filtered by a capacitor C806
220uto form a DC
voltage of about+300V, and the said DC voltage will be fed into the (1) of the power integrated circuit
N801
KA5Q1265RF-YDTU entry by the (1)(4) windings of switch transformer T801 BCK-100-02 ;
At start-up, the voltage from an AC single-phase power supply will be divided by starting resistors
R803 and R802 to provide starting voltage to N801. After start-up, an impulse voltage produced by
(6)
(7)windings of T801 will be rectified and provided. Photo coupler N802 PC817C entry serves the
function of voltage regulation. The error message about the voltage exported by the switch
transformer will be transmitted to the (4) of N801by the photo coupler N802, hence adjusting the
oscillation parameters of N801.
During stand-by time, POWER signals will be at a lower level, which causes the triode V803
KSC815to stop. So a voltage+12V will be put into the photo coupler N802PC817C entryby
resistor R849 and diode VD816, which feeds a special parameter to the (4) of N801 and makes the
N801 enter a quasi-resonance working state, with the power supply voltage (3) being 11V
12V. In
this way, the output voltage of the switch transformer T801will drop a great deal, resulting in a great
reduction of stand-by power consumption.
The impulse voltage sent out by the (8) of the secondary of switch transformer will be rectified and
filtered by VD805
D5L60 and C816 100u to produce a DC voltage +130Vfor power supply to line
output electrode;
The impulse voltage sent out by the (13) will be rectified and filtered by VD807
D6L20Uand C820
2200uto produce a DC voltage +15Vfor power supply to sound amplification circuit.
The impulse voltage sent out by the (11) will be rectified and filtered by VD806
TR5GU41 and C818
2200uto produce a DC voltage +12Vfor power supply to secondary power supply.
The DC voltage +8V sent out by the (8) of N804 after a voltage regulation of secondary power supply
will supply power to N201 decoding circuit, the DC voltage +3.3V obtained by the voltage regulation
power to N201 micro-processing circuit, and the DC voltage +5V sent out by the (9) will supply power
to a storage block N202
KS24C08circuit.
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Adjustment
14. Adjustment
Operating method: After a normal start-up, successively push the combination keys of mute, screen
display, -/--, screen display and mute on the workshop remote controller to enter a maintenance
menu.
Push numeric 0
Push P+/-
Push VOL+/- key to adjust the size of the present item;
Push MUTE key for mute/no mute switchover
Push the key for screen display retreat to retreat from the maintenance menu
Push the numeric 0 key Screen voltage adjustment
VG2
Adjust acceleration electrode to change the screen display from VG2
INSIDE HIGH/LOW
Maintenance menu 1 Geometric distortion (Table 8)
Table 8
Item Description
5PAR/6PAR Correction of four corners 0~63
5BOW/6BOW Bow-shape correction 0~63
5HSH/6HSH Correction of line center 0~63
5EWW/6EWW Correction of line width 0~63
5EWP/6EWP
5UCR/6UCR Correction of upper corners 0~63
5LCR/6LCR Correction of lower corners 0~63
Correction of geometric distortion will automatically fall into categories according to the present
identifiable 50/60hz systems.
Push numeric 2 key:
Maintenance menu 2 Geometric distortion (Table 9)
Table 9
Item Description
5EWT/6EWT Keystone correction 0~63
5VSL/6VSL Field inclination correction 0~63
5VAM/6VAM Field amplitude correction 0~63
5SCL/6SCL Field S correction 0~63
5VSH/6VSH Field center correction 0~63
5VOF/6VOF OSD vertical position 0~63 39
HOF OSD horizontal position 25
VX Vertical zoom 0~63 25 Unadjustable
S correction will be adjusted according to the curvature of a picture tube, and the picture tubes of the
same type possess the same S correction value.
Correction of geometric distortion will automatically fall into categories according to the present
INSIDE HIGH/LOW
7 keys for a rapid choice in the maintenance menu.
CH+/-key to choose items to be adjusted;
Adjusting
range
Correction of pillow-shaped
distortion
0~63
Adjusting
range
OUTSIDE HIGH/LOW to VG2
Default Remarks
Default Remarks
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Adjustment
identifiable 50/60hz systems.
Push numeric 3 key:
Maintenance menu 3 Picture adjustment
Table 10
Table 10
Item Description
RED
GRN
Mild color
Mild color
Red
Green
Adjusting
range
0~63
0~63
Default Remarks
32
32
WPR White neutralizing red 0~63
WPG White neutralizing green 0~63
WPB White neutralizing blue 0~63
YDFP Luminance delay PAL 0~15 7
YDFN Luminance delay NTSC
YDAV Luminance delay AV
White balance: Fully degauss the picture tube, consolidate R excitation, and adjust B and G excitation.
Push numeric 4 key:
Maintenance menu 4 (Table 11)
Table 11
Item Description
Adjusting
range
Default Remarks
TOP AGC control starting point 0~63 32
VOL UOC Volume output 0~63 44 Unadjustable
9874 TDA9874 Gain control 0~30 26 Unadjustable
AVLT Auto volume limit 0~3 1 Unadjustable
9860 TDA9860 Secondary volume control 0~100 59 Unadjustable
IFFS Intermediate frequency 0~7 2 Unadjustable
HDOL Cathode voltage 0~15 5 Unadjustable
AGC AGC Velocity 0~3 1 Unadjustable
VG2B VG2 Luminance 0~100 42 Unadjustable