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SERVICE MANUAL
FILE NO. SM-CTV-O-071
COLOR TELEVISION
SERVICE MANUAL
MODEL NO. 21C99/PF21C99
CHASSIS NO. EX-1A/1A1/1A2
ͼ±í 1
Please read this manual carefully before service
PRINTED IN CHINA.AUG .2003 ©
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SERVICE MANUAL
TABLE OF CONTENTS
SPECIFICATIONS··················································································································1
SAFETY INSTRUCTIONS AND MAINTENANCE ········································2
X-RAY RADIATION PRECAUTION ···································································································2
SAFETY PRECAUTION ····················································································································2
PRODUCT SAFETY NOTICE············································································································3
SAFETY SYMBOL DESCRIPTION ···································································································3
MAINTENANCE ·································································································································4
ADJUSTMENTS ······················································································································4
SET-UP ADJUSTMENTS···················································································································4
CIRCUIT ADJUSTMENTS ·················································································································7
CONTROL BUTTONS ····································································································· 13
CONTROL BUTTONS ···················································································································· 13
REMOTE CONTROL ······················································································································ 14
STRUCTURE AND CHASSIS FUNCTION DESCRIPTION ··············· 21
STRUCTURE BLOCK DIAGRAM ··································································································· 21
BLOCK DIAGRAM FOR SUPPLY VOLTAGE SYSTEM ································································· 22
CHASSIS DESCRIPTION··············································································································· 23
SERVICE DATA ···················································································································· 24
TECHNICAL DATA OF KEY ICS····································································································· 24
WAVEFORMS OF KEY POINTS ···································································································· 42
SERVICE DATA OF KEY ICS ········································································································· 43
REPLACEMENT OF PARTS ·········································································································· 47
APPENDIX
1. CIRCUIT DIAGRAMS
2. PRINTED CIRCUIT BOARD DIAGRAMS
3. FINAL WIRING DIAGRAMS
4. FINAL ASSEMBLY DIAGRAMS
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SERVICE MANUAL
SPECIFICATIONS
Model Number 21C99 PF21C99
Color
PAL4.43, NTSC3.58, NTSC4.43,SECAM
system
RF system
Sound D/K,I,M,B/G
system
Video system PAL4.43, NTSC3.58, NTSC4.43, PAL-M, PAL-N (50/60Hz)
VHF C1- C12 (49.75-85.25MHz, 168.25-216.25MHz)
Receiving UHF C13-C57 (471.25-863.25MHz)
channel Z1-Z7 (111.0-167.0MHz)
CATV
Z8-Z35 (223.0-447.0MHz)
Channels preset 236(0-235)
Antenna input 75¦¸ (unbalanced)
Picture tube Effective
screen dimensions 406¡Á 305mm
(Approx.)
Audio output
3W+3W
(THD¡Ü 7%)
Power source 110-240V ~, 50Hz
Weight (Approx.) 23kg 25kg
Dimensions
585¡Á 460¡Á 458mm
(W¡Á H¡Á D) (Approx.)
Rated power consumption
69W
220V AC 50Hz
Designs and specifications are subject to change without notice.
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SERVICE MANUAL
INSTRUCTIONS FOR SERVICE SAFETY AND MAINTENANCE
WARNING: BEFORE SERVICING THIS CHASSIS, READ THE ¡° X-RAY RADIATION PRECAUTION¡± ,
¡° SAFETY PRECAUTION¡± AND ¡° PRODUCT SAFETY NOTICE¡± INSTRUCTION BELOW.
X-RAY RADIATION PRECAUTION
1. The EHT must be checked every time the TV is serviced to ensure that the CRT does not emit
X-ray radiation as result of excessive EHT voltage. The maximum EHT voltage permissible in any
operating circumstances must not exceed the rated value. When checking the EHT, use the High
Voltage Check procedure in this manual using an accurate EHT voltmeter.
2. The only source of X-RAY radiation in this TV is the CRT. The TV minimizes X-RAY radiation, which
ensures safety during normal operation. To prevent X-ray radiation, the replacement CRT must be
identical to the original fitted as specified in the parts list.
3. Some components used in this TV have safety related characteristics preventing the CRT from
emitting X-ray radiation. For continued safety, replacement component should be made after
referring the PRODUCT SAFETY NOTICE below.
4. Service and adjustment of the TV may result in changes in the nominal EHT voltage of the CRT
anode. So ensure that the maximum EHT voltage does not exceed the rated value after service
and adjustment.
SAFETY PRECAUTION
WARNING: REFER SERVICING TO QUALIFIED SERVICE PERSONNEL ONLY.
1. The TV has a nominal working EHT voltage of 25kV. Extreme caution should be exercised when
working on the TV with the back removed.
1.1 Do not attempt to service this TV if you are not conversant with the precautions and procedures for
working on high voltage equipment.
1.2 When handling or working on the CRT, always discharge the anode to the TV chassis before
removing the anode cap in case of electric shock.
1.3 The CRT, if broken, will violently expel glass fragments. Use shatterproof goggles and take extreme
care while handling.
1.4 Do not hold the CRT by the neck as this is a very dangerous practice.
2. It is essential that to maintain the safety of the customer all power cord forms be replaced exactly
as supplied from factory.
3. Voltage exists between the hot and cold ground when the TV is in operation. Install a suitable
isolating transformer of beyond rated overall power when servicing or connecting any test
equipment for the sake of safety.
4. When replacing ICs, use specific tools or a static-proof electric iron with small power (below 35W).
5. Do not use a magnetized screwdriver when tightening or loosing the deflection yoke assembly to
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SERVICE MANUAL
avoid electronic gun magnetized and decrement in convergence of the CRT.
6. When remounting the TV chassis, ensure that all guard devices, such as nonmetal control buttons,
switch, insulating sleeve, shielding cover, isolating resistors and capacitors, are installed on the
original place.
7. Replace blown fuses within the TV with the fuse specified in the parts list.
8. When replacing wires or components to terminals or tags, wind the leads around the terminal
before soldering. When replacing safety components identified by the international hazard symbols
on the circuit diagram and parts list, it must be the company-approved type and must be mounted
as the original.
9. Keep wires away from high temperature components.
PRODUCT SAFETY NOTICE
CAUTION: FOR YOU PROTECTION, THE FOLLOWING PRODUCT SAFETY NOTICE SHOULD BE
READ CAREFULLY BEFORE OPERATING AND SERVICING THIS TV SET.
1. Many electrical and mechanical components in this chassis have special safety-related
characteristics. These characteristics are often passed unnoticed by a visual inspection and the
X-ray radiation protection afforded by them cannot necessarily be obtained by using replacements
rated at higher voltages or wattage, etc. Components which have these special safety
characteristics in this manual and its supplements are identified by the international hazard
symbols on the circuit diagram and parts list. Before replacing any of these components read the
parts list in this manual carefully. Substitute replacement components which do not have the same
safety characteristics as specified in the parts list may create X-ray radiation.
2. Do not slap or beat the cabinet or CRT, since this may result in fire or explosion.
3. Never allow the TV sharing a plug or socket with other large-power equipment. Doing so may result
in too large load, causing fire.
4. Do not allow anything to rest on or roll over the power cord. Protect the power cord from being
walked on, modified, cut or pinched, particularly at plugs.
5. Do not place any objects, especially heavy objects and lightings, on top of the TV set. Do not install
the TV near any heat sources such as radiators, heat registers, stove, or other apparatus that
produce heat.
6. Service personnel should observe the SAFETY INSTRUCTIONS in this manual during use and
servicing of this TV set. Otherwise, the resulted damage is not protected by the manufacturer.
SAFETY SYMBOL DESCRIPTION
The lightning symbol in the triangle tells you that the voltage inside this product may be
strong enough to cause an electric shock. Extreme caution should be exercised when
working on the TV with the back removed.
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SERVICE MANUAL
This is an international hazard symbol, telling you that the components identified by the
symbol have special safety-related characteristics.
FDA This symbol tells you that the critical components identified by the FDA marking have
special safety-related characteristics.
UL This symbol tells you that the critical components identified by the UL marking have
special safety-related characteristics.
C UL This symbol tells you that the critical components identified by the C-UL marking have
been evaluated to the UL and C-UL standards and have special safety-related
characteristics.
VDE This symbol tells you that the critical components identified by the VDE marking have
special safety-related characteristics.
MAINTENANCE
1. Install the TV set on a stable and level surface. Do not place the set near or over a radiator or heat
register, or where it is exposed to direct sunlight.
2. Do not install the TV set in a place exposed to rain, water, excessive dust, mechanical vibrations or
impacts.
3. Allow enough space (at least 10cm) between the TV and wall or enclosures for proper ventilation.
4. Slots and openings in the cabinet should never be blocked by clothes or other objects.
5. Please power off the TV set and disconnect it from the wall immediately if any abnormal condition
are met, such as bad smell, belching smoke, sparkling, abnormal sound, no picture/sound/raster.
Hold the plug firmly when disconnecting the power cord.
6. Unplug the TV set from the wall outlet before cleaning or polishing it. Use a dry soft cloth for
cleaning the exterior of the TV set or CRT screen. Do not use liquid cleaners or aerosol cleaners.
ADJUSTMENTS
SET-UP ADJUSTMENTS
The following adjustments should be made when a complete realignment is required or a new picture
tube is installed.
Perform the adjustments in the following order:
1. Color purity
2. Convergence
3. White balance
Notes:
¢Ù The purity/convergence magnet assembly and rubber wedges need mechanical positioning.
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SERVICE MANUAL
¢Ú For some picture tubes, purity/ convergence adjustments are not required.
1. Color Purity Adjustment
Preparation:
Before starting this adjustment, adjust the vertical sync, horizontal sync, vertical amplitude and
focus.
1.1 Face the TV set north or south.
1.2 Connect the power plug into the wall outlet and turn on the main power switch of the TV set.
1.3 Operate the TV for at least 15 minutes.
1.4 Degauss the TV set using a specific degaussing coil.
1.5 Set the brightness and contrast to maximum.
1.6 Counter clockwise rotate the R /B low brightness potentiometers to the end and rotate the green
low brightness potentiometer to center.
1.7 Receive green raster pattern signals.
1.8 Loosen the clamp screw holding the deflection yoke assembly and slide it forward or backward to
display a vertical green zone on the screen. Rotate and spread the tabs of the purity magnet
around the neck of the CRT until the green zone is located vertically at the center of the screen.
1.9 Slowly move the deflection yoke assembly forward or backward until a uniform green screen is
obtained.
1.10 Tighten the clamp screw of the assembly temporarily. Check purity of the red raster and blue raster
until purities of the three rasters meet the requirement.
Dummy Wedge
Deflection Coil
Rubber Wedge
Adhesive
Purity/Convergence
Magnet Module Deflection Yoke
Glass Cloth Tapes
Fig.1
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SERVICE MANUAL
6-pole Magnet
Fixed
4-pole Magnet
Adjust the Angle (Vertical Lines)
Rotate Two Tabs At the
Same Time (Horizontal Lines)
Purity Magnet Adjustment of Magnets
Convergence Magnet Assembly
Fig.2
2. Convergence Adjustment
Preparation:
Before attempting any convergence adjustment, the TV should be operated for at least 15 minutes.
2.1 Center convergence adjustment
2.1.1 Receive dot pattern.
2.1.2 Adjust the brightness/contrast controls to obtain a sharp picture.
2.1.3 Adjust two tabs of the 4-pole magnet to change the angle between them and red and blue
vertical lines are superimposed each other on the center of the screen.
2.1.4 Turn both tabs at the same time keeping the angle constant to superimpose red and blue
horizontal on the center of the screen.
2.1.5 Adjust two tabs of the 6-pole magnet to superimpose red/blue line and green line.
2.1.6 Remember red and blue movement. Repeat steps 3) ¡« 5) until optimal convergence is
obtained.
2.2 Circumference convergence adjustment
2.2.1 Loosen the clamp screw holding the deflection yoke assembly and allow it tilting.
2.2.2 Temporarily put the first wedge between the picture tube and deflection yoke assembly. Move
front of the deflection yoke up or down to obtain better convergence in circumference. Push the
mounted wedge in to fix the yoke temporarily.
2.2.3 Put the second wedge into bottom.
2.2.4 Move front of the deflection yoke to the left or right to obtain better convergence in
circumference.
2.2.5 Fix the deflection yoke position and put the third wedge in either upper space. Fasten the
deflection yoke assembly on the picture tube.
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SERVICE MANUAL
2.2.6 Detach the temporarily mounted wedge and put it in either upper space. Fasten the deflection
yoke assembly on the picture tube.
2.2.7 After fastening the three wedges, recheck overall convergence and ensure to get optimal
convergence. Tighten the lamp screw holding the deflection yoke assembly.
BLU Red Red/BLU GRN
BLU Red/BLU
Red GRN
4-pole Magnet Movement 6-pole Magnet Movement
Center Convergence by Convergence Magnets
Incline the Yoke up (or down) Incline the Yoke Right(or left)
Circumference Convergence by DEF Yoke
Fig. 3
3. White Balance Adjustment
Generally, white balance adjustment is made with professional equipment. It's not practical to get
good white balance only through manual adjustment. For TVs with I2C bus control, change the bus
data to adjust white balance.
CIRCUIT ADJUSTMENTS
Preparation:
Circuit adjustments should be made only after completion of set-up adjustments.
Circuit adjustments can be performed using the adjustable components inside the TV set. For TVs with
I2C bus control, first change the bus data.
1. Degaussing
A degaussing coil is built inside he TV set. Each time the TV is powered on, the degaussing coil will
automatically degauss the TV. If the TV is magnetized by external strong magnetic field, causing
color spot on the screen, use a specific degausser to demagnetize the TV in the following ways.
Otherwise, color distortion will be shown on the screen.
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SERVICE MANUAL
1.1 Power on the TV set and operate it for at least 15 minutes.
1.2 Receive red full-field pattern.
1.3 Power on the specific degausser and face it to the TV screen.
1.4 Turn on the degausser. Slowly move it around the screen and slowly take it away from the TV.
1.5 Repeat the above steps until the TV is degaussed completely.
2. Supply Voltage Adjustment
Caution: +B voltage has close relation to high voltage. To prevent X-ray radiation, set +B voltage to
the rated voltage.
2.1 Make sure that the supply voltage is within the range of the rated value.
2.2 Connect a digital voltmeter to the +B voltage output terminal of the TV set. Power on the TV and set
the brightness and sub-brightness to minimum.
2.3 Regulate voltage adjustment components on the power PCB to make the voltmeter read 115±1V.
3. High Voltage Inspection
Caution: No high voltage adjustment components inside the chassis. Please perform high voltage
inspection in the following ways.
3.1 Connect a precise static high voltmeter to the second anode (inside the high voltage cap) of the
picture tube.
3.2 Plug in the supply socket (220V, AC) and turn on the TV. Set the brightness and contrast to
minimum (0¦Ì A).
3.3 The high voltage reading should be less than the EHT limitation.
3.4 Change the brightness from minimum to maximum, and ensure high voltage not beyond the
limitation in any case.
Nominal EHT voltage: 26.5¡À 0.8KV Limited EHT voltage: 29KV(For 21C99/PF21C99 only)
4. Focus Adjustment
Caution: Dangerously high voltages are present inside the TV. Extreme caution should be
exercised when working on the TV with the back removed.
4.1 After removing the back cover, look for the FBT on the main PCB. There should be a FCB on the
FBT.
4.2 Power on the TV and preheat it for 15 min.
4.3 Receive a normal TV signal. Rotate knob of the FCB until you get a sharp picture.
5. Safety Inspection
5.1 Inspection for insulation and voltage-resistant
Perform safety test for all naked metal of the TV. Supply high voltage of 3000V AC, 50Hz (limit
current of 10mA) between all naked metal and cold ground. Test every point for 3 min. and ensure
no arcing and sparking.
5.2 Requirements for insulation resistance
Measure resistance between naked metal of the TV and feed end of the power cord to be infinity
with a DC-500 high resistance meter and insulation resistance between the naked metal and
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SERVICE MANUAL
degaussing coil to be over 20M¦¸ .
6. DESIGN/SERVICE mode
6.1 To enter the USER SERVICE mode
Caution: The user service mode adjustment can be changed only when service personnel adjust
the whole set data during servicing. As the control data have dramatic effects on functions and
performance of the TV, service personnel should not tell user how to
enter the SERVICE mode to avoid improper data settings. S
6.1.1 Set the volume to 0. Then press and hold the MUTE button on VS 0-3F 25
the remote control, and press the MENU button on the TV to xxxxxxxx
enter the SERVICE mode. (In this case, the S mode cannot be
stored in the EEPROM. To exit from the S mode, turn off the TV set. )
6.1.2 After entering the S mode, Red ¡° S¡± is displayed on the upper center of the screen and MENU1
is default. Use the POS+/- buttons to highlight an adjustment and the VOL+/- buttons to adjust
it. The adjusted data are immediately output and stored in the EEPROM
6.2 Bus data in the S mode
Item Bus Data Description Remarks
5PAR/6PAR 1F Parallelogram correction (for large-screen only)
5BOW/6BOW 1F Curve correction (for large-screen only)
5HSH/6HSH Set to the optimal Horizontal center in the TV mode for 50Hz/60Hz *
mode For 50Hz, ¡° 5HSH¡± is displayed£» for 60Hz, ¡° 6HSH¡±
is displayed.
5HSR/6HSR Set to the optimal Horizontal center in the RGB mode for 50Hz/60Hz *
mode For 50Hz, ¡° 5HSR¡± is displayed£» for 60Hz, ¡° 6HSR¡±
is displayed.
5EWP/6EWP 1F East-West parabola correction (for large-screen only)
5EWW/6EWW 1F East-West correction (for large-screen only)
5UCR/6UCR 1F Upper corner parabola correction (for large-screen only)
5LCR/6LCR 1F Lower corner parabola correction (for large-screen only)
5EWT/6EWT 1F Trapezoidal correction (for large-screen only)
5VSL/6VSL 1F Vertical slope (for large-screen only) *
5VAM/6VAM 1F Vertical amplitude *
For 50Hz, ¡° 5VAM¡± is displayed£» for 60Hz, ¡° 6VAM¡±
is displayed.
5SCL/6SCL Set to the optimal S correction *
mode
5VSH/6VSH Set to the optimal Vertical center *
mode
5VOF/6VOF Set to the optimal OSD vertical center *
mode
VX 19 Vertical zoom (for large-screen only)
RED 20 Red gun cutoff voltage *
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SERVICE MANUAL
GRN 20 Green gun cutoff voltage *
WPR 1F Red gun drive voltage *
WPG 1F Green gun drive voltage *
WPB 1F Blue gun drive voltage *
YDFP 07 PAL brightness delay time
YDFN 07 NTSC brightness delay time
YDFS 0F SECAM brightness delay time
YDAV 0F AV brightness delay time
TOP 1C UOC AGC *
VOL 32 UOC audio output amplitude *
IFFS 03£¨ 02£© PIF (02-38.9MHz, 03-38MHz)
HDOL 00 Cathode drive level
AGC 01 IF ACG speed
VG2B 30 VG2 brightness *
SBRI 1F Sub brightness
MBRI 2F Max. brightness
SCON 20 Sub contrast
MCON 39 Max. contrast
SCOL 32 Sub color
OP1 FF Option set byte 1
OP2 FF Option set byte 2
OP3 FF Option set byte 3
OP4 FF Option set byte 4
OP5 FF Option set byte 5
OP6 FF Option set byte 6
INIT EEPROM initialization
VG2 Adjusting screen voltage with VG2
VSD Vertical output off
USER_LOGO User logo write-in (valid when OP-USER-LOGO is 1)
STS0/1/2 System status byte
Notes:
¢Ù The data marked with ¡° *¡± have been adjusted in the MANUFACTURE mode. Take care when in
service and adjustment.
¢Ú To write in logo, use the ¡ý /¡ü buttons to highlight an adjustment and the ¡û /¡ú buttons to adjust.
¢Û The data sheet may differ dependent on different models.
¢Ü The data sheet may differ dependent on different CRTs for the same model.
6.3 Option set
With remote control system software TDA935X, all options can be set in the SERVICE mode and
stored in EEPROM. Data related to picture, sound and geometric adjustment are also stored in
EEPROM.
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SERVICE MANUAL
Bit Item Description Default
OP1 0 OP_HOTEL HOTEL mode 1
1 OP_236 100/236 programs preset 0
2 OP_NTSC NTSC option set 1
3 OP_AV2 Two set of AV terminals: 1-With AV2; 0-Without AV2 1A1-1
1A/1A2-0
4 OP_SVHS S-Video terminal 1A1-1
1A/1A2-0
5 OP_DVD DVD 1A1-1
1A/1A2-0
6 OP_RGB RGB: 1- RGB 0-No 1A1-0
1A/1A2-1
7 OP_OSO Switch off in vertical overscan 0
OP2 0 OP_AVL AVL 1
1 OP_AUTO_SOUND Auto sound system test 1
2 OP_NOT_1 National Option Set (OP_NOT_3/2/1)£º 1XX-Arabic£¬ 0
3 OP_NOT_2 011-Farsi£¬ 010-Russian£¬ 001-Ukrainian£¬ 000-Paneuro 0
4 OP_NOT_3 0
5 OP_USER_LOGO User logo£¨ prior to CHANGHONG logo£© 0
6 OP_ON_BACK Auto test background options when power-on: 0
0-black; 1-blue
7 OP_FSL Slicing level for vertical sync 0
OP3 0 OP_ENGLISH English 1
1 OP_FARSI Farsi 1
2 OP_ARABIC Arabic 1
3 OP_RUSSIAN Russian 1
4 OP_FRENCH French 1
5 OP_GERMAN German 1
6 OP_INDIA Indonesian 1
7 OP_MALAYSIA Malay 1
(continued)
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SERVICE MANUAL
OP4 0 OP_FMWS Window selection of sound pll: small/large window 0
1 OP_DIRECT_SWIT Memory power-on (If turned off by the remote 1
CH_ON control, then the TV is turned on by the remote
control; if turned off by the MAIN POWER SWITCH,
then turned on by the MAIN POWER SWITCH.)
2 OP_HCO EHT tracking mode 0
3 OP_CHH_LOGO User logo display £º 1-Displayed without signal 1
reception£» 0-No
4 OP_SOUND_DK Sound system-DK option set 1
5 OP_SOUND_BG Sound system-BG option set 0
6 OP_SOUND_I Sound system-I option set 1
7 OP_SOUND_M Sound system-M option set 1
OP5 0 OP_TUNER Tuner£º 1-Philips Tuner 0-Panasonic Tuner 0
1 OP_AUTO_LANG0 Auto language option set: English - Farsi - Arabic - 1
2 OP_AUTO_LANG1 Russian - French - German - Indonesian - Malay 0
3 OP_AUTO_LANG2 0
4 OP_FORF Field frequency options (OP_FORS/FORF): 0
5 OP_FORS 00-Auto60Hz, 01-KeepLast£¬ 10-Force60Hz, 0
11-Auto50Hz
6 OP_AVON If AV off, then AV on 1
7 OP_ONPOSITION With HOTEL mode preset, on position is fixed to 0
POS1.
OP6 0 OP_AUTOTEST Auto test when power-on 0
1 OP_PSNS Sensitivity 0
2 OP_BSCREEN Black screen when changing channels: 1-yes£» 0-No 1
3 OP_SECAM 1: SECAM option 1
4 OP_DFL Disable flash protection 0
5 OP_SIF External input for sound IF circuit 1
6 OP_EXT_SIF0 Sound system options for external circuit: 00-DK, 1
7 OP_EXT_SIF1 01-BG, 10-I, 11-M 0
(Valid when OP_SIF = 1)
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SERVICE MANUAL
CONTROL BUTTONS
1 CONTROL BUTTONS
21C99/PF21C99
Front panel
AV IN on the side panel
MAIN POWER SWITCH
INFRARED SENSOR
POWER INDICATOR
MENU SELECT
TV/AV VOLUME CHANNEL
SELECT DOWN/UP DOWN/UP
Rear panel
SCART terminal ANTENNA IN
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SERVICE MANUAL
2 REMOTE CONTROL
The chassis uses a KEX1D-C1 remote control.
2.1 Remote Control
¡¤ The buttons in the frame act as TELETEXT function selection.
¡¤ The color and INDEX buttons also function as fast menu selection in the TV mode.
Notes:
¢Ù When in operation, please point your remote control directly to the infrared sensor.
¢Ú Do not expose the remote control to impacts, water or disassemble it.
¢Û Do not repeatedly press the buttons on the remote control.
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SERVICE MANUAL
2.3 Tuning in by the remote control
Power On/Off
1. Power on
Plug in the supply socket and press the MAIN POWER SWITCH on the TV. The TV enters the former
mode before turn-off, i.e. the TV directly enters the TURN ON mode if in the TURN ON mode before
turn-off, or enters the STANDBY mode if in the STANDBY mode before turn-off. In this case, you may
press any of the , CH+/CH-¡ 0¡« 9 buttons on the remote control or -CH+ on the TV to turn on
the TV.
Each time turn on, the set will automatically enter AV or RGB mode if with signals input to the SCART
terminals, if not, the set will enter TV mode.
2. Power off
When the TV in the TURN ON mode, press the button to shift the TV to the STANDBY mode,
press the MAIN POWER SWITCH directly to power off the TV at once.
Part of circuit on the TV remains active in the STANDBY mode. To cut off the power off completely,
please press the MAIN POWER SWITCH.
Note:
Avoid switching the TV on and off frequently. Doing so may shorten life span of internal components.
Auto off without signal received
When a channel has no signal (e. g. program is over), the TV will automatically turn off if no button is
pressed within 15 minutes. If Off Time/Sleep Time is preset and the time left is less than 15 minutes,
the TV will carry out the Off Time/Sleep Time prior to the auto-off.
Intelligent Operation
Press and hold down the AUTO button for 2 sec. and the TV automatically completes some settings,
such as settings of language, volume, picture mode, color system and sound system. Then it starts
Auto Program. After ASM, The TV returns to POS 1. At this time, you may watch the TV program.
On Screen Display
When switching channels, the current channel number will appear on the
2
upper-left corner of the screen, which will disappear in 3 sec. AUTO
Press the DISPLAY button firstly when watching TV to display channel B/G
number, color/sound system modes on the screen. To turn off the display,
press the button again.
Pressing the DISPLAY button can turn off menu display.
15
SERVICE MANUAL
Menus
Press the MENU button repeatedly when watching TV programs, and the TV will display eight kinds of
menus (including PICTURE, SOUND, TIMER, SETUP, TUNE, SWAP, HOTEL and BIORHYTHM)
cyclically.
Press the CH+/CH- buttons to select an adjustment (the characters turn white to cyan), and press the
VOL-/VOL+ buttons to adjust. (Press the HELP button, and the operation hint will appear on the
upper-right conner of the menu.)
Menu display disappears 6 sec. after last selection.
Note:
In the AV mode, TUNE and SWAP menu is not available.
Tuning in
This section gives descriptions about adjustment of items in the TUNE menu.
1. Auto program
After selecting "Auto Program" in the TUNE menu, press the VOL+ TUNE
button. The TV will search automatically in sequence. After auto Color AUTO
Sound B/G
search, the TV will store receivable channels and returns to POS 1. Band VHFL
Skip Off
Unused position number is automatically set to Skip On. Channel 66
Search
During auto program, press the MENU button to stop searching. Fine Tune
Auto Program
2. Search
In case the desired channel cannot be preset with the Auto Program function, or you would like to set
the desired channels to specific channel numbers, please use the Search function.
After selecting "Search" in the TUNE menu, press the VOL-/VOL+ buttons. The TV searches another
lower/upper channel. To stop search, press the MENU button.
If the selected channel is not the one you want, press the buttons again until the desired channel is
selected. If the TV does not stop searching when finding a channel, please use the Fine Tune
function.
3. Frequency fine-tuning
After selecting "Fine Tune" in the TUNE menu, press and hold down the VOL- or VOL+ button until
you get the best sound and picture effect.
Press the DISPLAY button to check up the fine-tuned channel, and you will find that the position
number turns to red.
4. Color/Sound system selection
In case the color/sound of a channel that you are watching is abnormal, please change the
color/sound system.
16
SERVICE MANUAL
Tuning in (continued)
You can select a suitable system from the following systems, which are displayed in a circular way.
Color, AUTO, PAL, NTSC, NTSC443, SECAM
Sound, D/K, B/G, I, M
Tuning in, continued,
5. Skip
After Auto Program, there may be some repeated program or inferior signals received. Skipping the
undesired program position can dramatically quicken channel selection.
After selecting "Skip" in the TUNING menu, press the VOL-/VOL+ buttons to set "Skip On". When the
TUNE menu has disappeared, press the CH-/CH+ buttons and you will find the channel number
skipped. If you select the channel number by the Direct Select buttons, the channel number has
changed from green to yellow.
To resume the channel number that has been skipped¡ repeat the operations mentioned above.
Then set "Skip Off".
Setup
To perform the following operation, press the MENU button repeatedly or SETUP button directly ,in the
TV/AV mode, to select the SETUP menu.
1. Language selection
You may switch the language for the OSD to English, Russian, SETUP
Hungarian, Slovakian, Czech, Croatian or German. English
Blue Back On
2. Blue background PIC Enhance On
Color Temp Cool
With this function on, the screen will display a mild blue background. AVL Off
3. Picture enhancement
If the picture of a certain channel is abnormal, use this function to improve picture.
It is recommended to select "PIC Enhance Off" when the signal being received is good in case of
influencing picture definition.
4. Color temperature adjustment
You may select one of color of background as preferred among Standard, Cool and Warm mode.
The adjusted Color Temp mode is automatically stored and remains unchanged until next
adjustment.
5. AVL(Auto Volume Leveling)
When the AVL is activated, it automatically stabilizes the audio output signal to a certain level.
17
SERVICE MANUAL
General Operation
1. Volume control
1) Press the VOL- or VOL+ button to decrease or increase the volume.
Adjustable range, 0¡« 63
2) During normal play, press the MUTE button and the sound is eliminated. The TV will display a red
MUTE on the screen.
To cancel MUTE, you may press the MUTE button again or the VOL-/VOL+ buttons.
2. Channel selection
1) Pressing the CH-/CH+ buttons can select another lower-numbered or upper-numbered channel.
2) Direct Selection
¡¤ To select a one-digit channel number
Press the DIGIT button to choose " - " firstly, then press one of 0-9 buttons.
¡¤ To select a two-digit channel number
Press the DIGIT button to choose " - - " firstly, then enter a first-digit and second-digit.
¡¤ To select a three-digit channel number
Press the DIGIT button to choose " - - - " firstly, then enter a first-digit, second-digit and third-digit.
Note£º
Please finish entering within 6 sec.
3) RECALL
Press the RECALL button and the TV will directly skip back to the former signal source reception
mode.
3. TV/AV selection
In the TV mode, press the TV/AV button to enter the AV mode. With SCART signal input¡ the TV
automatically enters the AV/RGB mode to receive SCART signals even if the button isn£§ t pressed. In
the AV mode, the TV receives AV signals from external equipment and automatically cuts off signals
from the antenna terminal. To resume broadcast viewing, press the TV/AV button repeatedly or
CH-/CH+ buttons.
To receive signals from external equipment, please select the relevant AV mode.
18
SERVICE MANUAL
Picture Improvement
1. Picture mode selection
Before shipment, the TV was given three preset picture modes: Mild, Nature and Vivid. Press the
P.MODE button to select one of the three preset modes or the User mode.
Refer to the following table about each picture mode.
Mode Picture Quality
Mid The contrast is low, Suitable for watching TV in mild surrounding light.
Nature Standard status, suitable for watching ordinary programs.
Vivid The contrast is high, suitable for watching TV in bright environment.
User Picture quality user sets
2. To adjust picture quality
To perform the following operation, press the MENU button repeatedly or PICTURE button directly
(in the TV/AV mode) to select the PICTURE menu. Press the CH-/CH+ buttons to choose an
adjustment. Press the VOL-/VOL+ buttons to adjust the digital level of the selected adjustment as
desired.
Ltem Adjustment Effect
PICTURE
Press VOL- Press VOL+
Contrast 32
Brightness 37 Contrast Lower Higher
Color 50
Sharpness Brightness Darker Brighter
50
Tint 0 Color Weaker Stronger
¨...¨...¨...¨...¨...¨...¨...¨............ Sharpness Lower Higher
Tint More Purple More Green
The adjusted picture level is automatically stored in the User position.
Notes:
¢Ù "Tint" appears only when the signal system is set to NTSC.
¢Ú The adjustable "Tint" range is -31¡« +31, and other adjustments are 0¡« 63.
19
SERVICE MANUAL
Sound Improvement
1. Sound mode selection
Before shipment, the TV was given three preset sound modes: News, Theater and Music. Press the
S.MODE button to select one of the three preset modes or the User mode.
Refer to the following table about each sound mode.
Mode Picture Quality
News Language clarity improvement, suitable for program focusing on dialogue
Movie-like sound setting, suitable for enjoying dynamic sound, such as
Theater
programs of entertainment
Music Suitable for enjoying music
User Sound quality user sets
2. To adjust sound quality
To perform the following operation, press the MENU button repeatedly or SOUND button directly (in
the TV/AV mode) to select the SOUND menu. Press the CH-/CH+ buttons to choose an adjustment.
Press the VOL-/VOL+ buttons to adjust the digital level of the selected adjustment as desired.
Ltem Adjustment Effect
SOUND
Press VOL- Press VOL+
Volume 20
Bass 39 Bass
Treble 48 Weaker Stronger
Balance 0 Treble
¨...¨...¨...¨...¨...¨...¨...¨............ Balance To the left To the right
The adjusted sound level is automatically stored in the User mode position.
Note:
The adjustable "Balance" range is -31¡« +31¡ and other adjustments are 0¡« 63.
20
STRUCTURE AND CHASSIS FUNCTION DESCRIPTION
1.STRUCTURE BLOCK DIAGRAM
From
Antenna IF Pre-
Tuner Amplifier Analog Switc h Audio/Video
A101 + HEF4053 Input/Output
SAWF
Band 1,2
Vt,AGC
CRT
IIC BUS Video
Amplisier
EEPROM UOC
TDA6107Q
AT24C08 TDA935X/6X/8X
Audio
Input Audio Prec essor V.OUT
H.Drive
TDA7449 TDA8356J
Audio Amp lifier
TDA7057AQ FBT
H.OUT
T402
+115V
90-270V~,50Hz Power Supply Circuit
R
STR-F6654 or +15V
STR-G5653
Speaker
+5V-2 +3.3V
L
Fig.4 S t r u c t u r e B l o c k D i a g r a m f o r E X - 1 A / 1 A 1 / 1 A 2 C h a s s i s S e r i e s
21
2.BLOCK DIAGRAM FOR SUPPLY VOLTAGE SYSTEM
VD491 +190V
To CRT RGB PCB
VD451 +45V
To A100,N401
FBT VD461 +16V
T400
To N401
VD471
+8V To A100,
N442 N100,
+115V N650
VD891
VD871 +15-S
+5V-2
N441 To A100
Bridge Rectifying To N600
Power Regulat ion Switch
Filter
and Control Circuit Transformer
VD803~VD806 VD881 +15V-H
STR-G5653/F6654 T804
C802,C807
Regulator
Line Filter
Feedback Circuit V115
L801,C801,
N801
C802
To H Out
EEPROM
+5V-1 R/C Input
Error Signal +3.3V
Regulator
V871, To N100
VD882 Keyboard
110-240V~,50/60Hz
Fig .5 Block Diagram for EX-IA/1A1/1A2 Supply Voltage System
22
SERVICE MANUAL
3.CHASSIS DESCRIPTION
1). General Description
EX-1A/ EX-1A1/ EX-1A2 chassis series are applied in 21C99/PF21C99 respectively which uses
mainly Philips' advanced UOC-ultimate chip TDA935X/6X/8X and I2C-bus controlled IC. With
combination of microcontroller and small signal processor, the TDA935X/6X/8X series feature
high-integration, high-performance-to-price ratio and high-reliability and advanced functions with
fewer external components, which provide much convenience for manufacturing and technical
service.
The following features are available in the chassis series:
PAL/NTSC/SECAM reception
100/236 programs preset
Various input/output terminals including SCART, RCA and S-VIDEO
Selectable picture/sound modes
Multilingual on screen display
TELETEXT option
Audio effect processing
Blue background and mute
User logo
Biorhythm
Hotel video locking
Differences between EX-1A and EX-1A1/ EX-1A2:
Different PCB layouts: EX-1A-Horizontal layout; EX-1A1/EX-1A2-Vertical layout
EX-1A/EX-1A2 have SCART terminal, but EX-1A1 not.
2). The EX-1A/1A1/1A2 chassis series mainly use the following ICs and assemblies.
Table 1 Key ICs and Assemblies
Serial Position Type Function Description
No.
1 N100 TDA935X/6X/8X Microcontroller and small signal processor(UOC)
2 N200 AT24C08 EEPROM
3 N650 TDA7449 Audio processor
4 N401 TDA8356/N6 Vertical scan output stage circuit
5 N600/N601 TDA7057AQ Sound power amplifier
6 N861/N881 STR-G5653/F6654 Power supply circuit
7 N402 HEF4053 Analog switch
8 A100 TDQ-5B6M Tuner
23
SERVICE MANUAL
SERVICE DATA
1. KEY ICS TECHNICAL DATA
1.1 Microcontroller and small signal processor TDA935X/6X/8X
The super chips TDA935X/6X/8X are good in pins compatibility. Differences among them are shown
as follows.
TDA9351£¨ 48K£© PAL/NTSC/SECAM+1 PAGE TELETEST
TDA9350£¨ 48K£© PAL/NTSC+1 PAGE TELETEST
TDA9361£¨ 64K£© PAL/NTSC/SECAM+10 PAGE TELETEST
TDA9360£¨ 64K£© PAL/NTSC+10 PAGE TELETEST
TDA9380£¨ 32K£© PAL/NTSC
TDA9387£¨ 32K£© NTSC
TDA935X/6X/8X PS/N2 series TV signal processor-Teletext decoder with embedded
¡ -Controller
1) General Descripion
The various versions of theTDA935X/6X/8X PS/N2 series combine the functions of a TV signal
processor together with a ¡ -Controller and US Closed Caption decoder. Most versions have a
Teletext decoder on board. The Teletext decoder has an internal RAM memory for 1or 10 page text.
The ICs are intended to be used in economy television receivers with 90¡ and 110 picture tubes.
¡ ¡ ¡
The ICs have supply voltages of 8 V and 3.3 V and they are mounted in S-DIP envelope with 64
pins.
The features are given in the following feature list. The differences between the various ICs are
given in the table on page 4.
2) Features
TV-signal processor
¡ Multi-standard vision IF circuit with alignment-free PLL demodulator
¡ Internal (switchable) time-constant for the IF-AGC circuit
¡ A choice can be made between versions with mono intercarrier sound FM demodulator and versions
with QSS IF amplifier.
¡ The mono intercarrier sound versions have a selective FM-PLL demodulator which can be switched
to the different FM sound frequencies (4.5/5.5/6.0/6.5 MHz).
The quality of this system is such that the external band-pass filters can be omitted.
¡ Source selection between `internal' CVBS and external CVBS or Y/C signals
¡ Integrated chrominance trap circuit
¡ Integrated luminance delay line with adjustable delay time
¡ Picture improvement features with peaking (with variable centre frequency and positive/negative
overshoot ratio) and black stretching
¡ Integrated chroma band-pass filter with switchable centre frequency
¡ Only one reference (12 MHz) crystal required for the
¡ -Controller, Teletext- and the colour decoder
¡ PAL/NTSC or multi-standard colour decoder with automatic search system
¡ Internal base-band delay line
24
SERVICE MANUAL
¡ RGB control circuit with `Continuous Cathode Calibration', white point and black level offset
adjustment so that the colour temperature of the dark and the light parts of the screen can be
chosen independently.
¡ Linear RGB or YUV input with fast blanking for external RGB/YUV sources. The Text/OSD signals
are internally supplied from the ¡ -Controller/Teletext decoder
¡ Contrast reduction possibility during mixed-mode of OSD and Text signals
¡ Horizontal synchronization with two control loops and alignment-free horizontal oscillator
¡ Vertical count-down circuit
Vertical driver optimized for DC-coupled vertical output stages
¡ Horizontal and vertical geometry processing
¡ Horizontal and vertical zoom function for 16 : 9 applications
¡ Horizontal parallelogram and bow correction for large screen picture tubes
¡ Low-power start-up of the horizontal drive circuit
TV signal processor-Teletext decoder with embedded ¡ -Controller TDA935X/6X/8X PS/N2
series ¡ -Controller
¡ 80C51 -controller¡ core standard instruction set and timing
¡ ¡
¡ ¡ 1 ¡ ¡ s machine cycle
16 - 128Kx8-bit late programmed ROM
¡ 3 - 12Kx8-bit DATA RAM (shared between Display, Acquisition and Auxiliary Ram)
¡ Interrupt controller for individual enable/disable with two level priority
¡ Two 16-bit Timer/Counter registers
¡ One 16 bit Timer with 8-bit Pre-scaler
WatchDog timer
¡ Auxiliary RAM page pointer
¡ 16-bit Data pointer
¡ Stand-by, Idle and Power Down (PD) mode
¡ 14 bits PWM for Voltage Synthesis Tuning
¡ 8-bit A/D converter
¡ 4 pins which can be programmed as general I/O pin, ADC input or PWM (6-bit) output
Data Capture
¡ Text memory for 0, 1 or 10 pages
¡ In the 10 page versions inventory of transmitted Teletext pages stored in the Transmitted Page Table
(TPT) and Subtitle Page Table (SPT)
¡ Data Capture for US Closed Caption
¡ Data Capture for 525/625 line WST, VPS (PDC system A) and Wide Screen Signalling (WSS) bit
decoding
¡ Automatic selection between 525 WST/625 WST
¡ Automatic selection between 625 WST/VPS on line 16 of VBI
¡ Real-time capture and decoding for WST Teletext in Hardware, to enable optimized ¡ -processor
throughput
¡ Automatic detection of FASTEXT transmission
¡ Real-time packet 26 engine in Hardware for processing accented, G2 and G3 characters
¡ Signal quality detector for video and WST/VPS data types
25
SERVICE MANUAL
¡ Comprehensive teletext language coverage
¡ Full Field and Vertical Blanking Interval (VBI) data capture of WST data
Display
¡ Teletext and Enhanced OSD modes
¡ Features of level 1.5 WST and US Close Caption
¡ Serial and Parallel Display Attributes
¡ Single/Double/Quadruple Width and Height for characters
¡ Scrolling of display region
¡ Variable flash rate controlled by software
¡ Enhanced display features including overlining, underlining and italics
¡ Soft colours using CLUT with 4096 colour palette
¡ Globally selectable scan lines per row (9/10/13/16) and character matrix [12x10, 12x13, 12x16
(VxH)]
¡ Fringing (Shadow) selectable from N-S-E-W direction
¡ Fringe colour selectable
¡ Meshing of defined area
¡ Contrast reduction of defined area
¡ Cursor
¡ Special Graphics Characters with two planes, allowing four colours per character
¡ 32 software redefinable On-Screen display characters
¡ 4 WST Character sets (G0/G2) in single device (e.g. Latin, Cyrillic, Greek, Arabic)
¡ G1 Mosaic graphics, Limited G3 Line drawing characters
¡ WST Character sets and Closed Caption Character set in single device
Functional Difference Between The Various Ic Versions
Ic Version (TDA) 9350 9351 9352 9353 9360 9361 9362 9363 9364 9365 9366 9367 9380 9381 9382
9383 9384 9385 9386 9387 9388 9389
26
3) Block Diagram
27
SERVICE MANUAL
Fig.6 Block Diagram for TDA935×/6×8×PS/N2 with Mono Intercarrier Sound Demodulator
28
SERVICE MANUAL
Fig.7 Block Diagram for TDA935×/6×8×PS/N2 with QSS IF Sound Channel
SERVICE MANUAL
4) pinning
SYMBOL PIN DESCRIPTION
P1.3/T1 1 port 1.3 or Counter/Timer 1 input
P1.6/SCL 2 port 1.6 or I2C-bus clock line
P1.7/SDA 3 port 1.7 or I2C-bus data line
P2.0/TPWM 4 port 2.0 or Tuning PWM output
P3.0/ADCO/PWMO 5 port 3.0 or ADC0 input or PWM0 output
P3.1/ADC1/PWM1 6 port 3.1 or ADC1 input or PWM1 output
P3.2/ADC1/PWM2 7 port 3.2 or ADC2 input or PWM2 output
P3.3/ADC3/PWM3 8 port 3.3 or ADC3 input or PWM3 output
VSSC/P 9 digital ground for ¦Ì -Controller core and periphery
P0.5 10 port 0.5 (8mA current sinking capability for direct drive of LEDs)
P0.6 11 port 0.