THOMSON CR20300 User manual

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1 - GENERAL SPECIFICATIONS
1.1 Product Models:
• CR14300/20300...................................................................MONO conventional model;
• CR20310..................................................................................................STEREO SAP;
• CR29411..................................................................................................STEREO SAP.
1.2 Power Supply:
a Power Source Range.........................................................................99VAC to 242VAC.
b Power Supply: automatic commutation.
c Power Consumption:
• Model CR14300......................................................................................................60W;
• Model CR20300......................................................................................................72W;
• Model CR20310......................................................................................................80W;
• Model CR29411....................................................................................................130W;
• STAND BY..................................................................2W (120VAC and 3W (220VAC .
d High Voltage (Fly back Anode Voltage and beam current:
• High Voltage: CR14300/20300....................................................................22 ± 1.5 KV;
• Beam current - with brightness and contrast at the maximum...................0.7 + 0.1 mA;
• CR20310...............................................................................23 + 1.5 KV;
• Beam current - with brightness and contrast at the maximum...................0.9 + 0.1 mA;
• CR29411............................................................................27.5 + 1.5 KV;
• Beam current - with brightness and contrast at the maximum...................1.4 + 0.1 mA;
e Heating:..............................................................................................6.15 + 0.15 Vrms.
f FLY BACK Main Power Supply :
• “Fly back” Output Voltage CR14300...……..................105 ± 2 V DC; max ripple 2 Vpp;
• “Fly back” Output Voltage CR20300 e CR20310…....108.5 ± 2V DC; max ripple 2 Vpp;
• “Fly back” Output Voltage CR29411………..................130 ± 2V DC.; max ripple 2 Vpp.
1.3 Tuner and Receiving channel:
• Channel Coverage............................……………………. 181 channels VHF/UHF/cable.
• Color System: ………….........................................................PAL-N , PAL-M and NTSC;
1.4 Video Signal - Resolution:
• Horizontal .......................................................................................................260 lines.
• Vertical............................................................................................................330 lines.
1.5 Intermediate Frequency:
• Video carrier..................................................................................................45.75Mhz;
• Audio carrier..................................................................................................41.25Mhz;
• Chrome carrier...............................................................................................42.17Mhz.

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1.6 Carrier System:
• Audio...................................................................................................................4.5Mhz;
• PAL-M Chrome........................................................................................3,575.611Mhz;
• NTSC Chrome..........................................................................................3,579.545Mhz;
• PAL-N Chrome.........................................................................................3,582.056Mhz.
1.7 Speaker Output:
• CR14300/20300.....................................…………………...............................2.5W rms;
• CR20310.........................................................…………………..........2.5W + 2.5W rms;
• CR29411..............................................................…………………...........5W + 5W rms.
1.8 Antenna Input Impedance:
• VHF/UHF/CABLE................................................75Ω unbalanced (“F” type connector .
1.9 Terminals:
• Rear and front audio (mono and video input …..................................CR14300/20300;
• Rear and front audio (stereo and video input ...............................................CR20310;
• Two rear and one front audio (stereo and video input...................................CR29411;
• Input minimum impedance…....................................................................10kOhms;
• Audio input signal level................................................................400 to 800mVrms;
• Video input signal level.....................................................................................1Vpp.
• Rear Audio output …………………….. ....................................CR29411 and CR20310;
• Output maximum impedance......................................................................1kOhms;
• Variable output level (maximum volume ....................................................1.5Vrms;
1.10 Dimensions (WxDxH):
• CR14300...........................................................................................358.5x383x349 mm;
• CR20300..............................................................................................486x488x446 mm;
• CR20310..............................................................................................486x488x446 mm;
• CR29411..............................................................................................754x529x578 mm.
1.11 Weight:
• CR14300................................................................................................................8.9kg;
• CR20300..............................................................................................................17.1kg;
• CR20310..............................................................................................................17.2kg;
• CR29411..............................................................................................................34.3Kg.

2. DISASSEMBLY INSTRUCTIONS
Removal of mechanical parts and P.C. boards.
2.1 Back cabinet (refer to fig. 2.1)
a. Remove the screws which are used for holding the back cabinet to the front cabinet (6
screws for 14” models, 8 screws for 20” and 29” models).
b. Remove the screws which are used for holding the rear A/V input and output connectors.
c. Remove the back cabinet.
2.2 CRT PCB (refer to fig. 2.2/2.3)
CAUTION: Before removing the anode cap, discharge electricity because it contains high
voltage. Before attempting to remove or repair any PCB, unplug the power cord from the AC
source.
a. Remove the anode cap.
b. Disconnect the ground connector (CM801).
c. Remove the CRT PC board.
2.3 Main PCB (refer to fig. 2.2/2.3)
a. Disconnect the following connectors: CM901, CM902, CM701, CM601, CM401 and
CM402
b. Unlock the PCB from the cabinet (both side of the board).
c. Remove the main PCB.
2.4 CRT (refer to fig. 2.4)
a. Remove the 4 screws.
b. Remove the CRT.
Note: REMOVAL OF ANODE CAP –After turning the power off there might still be a
potential voltage that is very dangerous. When removing the ANODE CAP, make sure to
discharge the anode cap’s potential voltage. Do not use pliers to loosen or tighten the
anode cap terminal, this may cause the spring to be damaged.

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3. ON-SCREEN DISPLAY ADJUSTMENT – SERVICE MODE
3.1 Memory Initialization
If a service repair is undertaken where it has been required to change the MEMORY IC (IC101 and
IC10 ) the following steps should be taken to ensure correct data settings: " memory initialization":
• Unplug the power cord from the AC Power Source;
• While holding down “MENU” button and “VOLUME –“ button (front panel), plug the power cord in
the AC Power Source (wait seconds before release the buttons).
• Turn on the TV set through front panel “POWER” button or remote control.
• To certify that the initialization was success executed, it will appear the following message:
ILLUSTRATION 1
3.2 OSD Adjustment – Service Mode
• Unplug the power cord from the AC source;
• While holding down “MENU” button (front panel), plug the power cord in the AC Source (wait
seconds before release the button);
• Press and hold the “MENU” and “VOLUME +” buttons (front panel) during seconds;
• Turn on the TV set using “POWER” button (front panel or remote control unit).
• Press “MENU” button to display the first “SERVICE MENU”.
• Press “VOLUME +” and “VOLUME –“ buttons for navigation menus in service mode;
• Press “CHANNEL +” and “CHANNEL –“ buttons to select one service menu item;
• Press “MENU” button to activate the item adjustment. Press “VOLUME +” or “VOLUME-“ to set the
value adjustment”;
• Press “MENU” button to return to the previous “SERVICE MENU” (for another selection).
To exit the service mode, press “MENU” button and turn off the TV set.
To Run Automatic
Tuning Now
Plug the Antenna
<No Yes>

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3.3 Service Menu Items:
HP = Horizontal Parallelogram RGB = OSD Bright
HB = Horizontal Bowl SBL= Services Blanking
HSH = Horizontal Shift Adjust FFI = IF Filter
VS = Vertical Slope MAT = Color Matrix
VA = Vertical Amplitud BKS = Black Stretch
SC = Vertical S-Correction EVG = Vertical Guard
VSH = Vertical Shift FMWS = Sound PLL
BLR = Red Black Level Offset SL = Audio level Adjust
BLG = Green Black Level Offset ADJ = Stereo Adjust
WR = White Point (red) A1 = Wideband
WG = White Point (green) A2 = Spectral
WB = White Point (blue) TC = ST current Adjust
Yn = Y Delay for NTSC FETRACK = RF Phase1 Time
Yp = Y Delay for PAL AVTRACK = AV Phase1 Time
Yav = Y Delay for Avin MODEL = Model Identification
FSL= Vertical Sync Slicing Level BLKCURR = G Adjust
CL= Cathode Drive Level ORIGMAG = Factory Picture Settings
AGCT = AGC Adjust VO.3P = Software Version
AGCS = AGC Delay
SERVICE
HP
HB
HSH
VS
VA
SERVICE
SC
VSH
BLR
BLG
WR
SERVICE
WG
WB
Yn
Yp
Yav
SERVICE
FSL
CL
AGCT
AGCS
RGB
SERVICE
ORIGMAG
VO.3P
SERVICE
TC
FETRACK
AVTRACK
MODEL
BLKCURR
SERVICE
FMWS
SL
ADJ
A1
A2
SERVICE
SBL
FFI
MAT
BKS
EVG

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3.4 AGC Adjustment
• Apply a color bar pattern (RF Input) with 500µV signal;
• Connect a DC Voltmeter, in the AGC pin of the tuner;
• Adjust AGCT to Zero and measure the voltage (V1);
• Adjust AGCT so that the indication on the voltmeter be (V1) - 1 ± 0. V.
3.5 Stereo Adjustment
• For the adjustments, proceed according to illustration ;
• Adjust output indicated by “A” to tension equal to half of VCC plus 1V ;
• Adjust TC to an indication in the microAmpère meter of 4µA in the pin 17 of IC450;
• Apply 300Hz/Mono/ 5KHz of deviation, 50mVrms, in the pin 9 of IC450;
• Adjust SL to 500± 0mVrms in the pins 15 and 38 of IC450;
• Apply in the channel L=300Hz and in the channel R= 3k, 14% of generator Stereo modulation
DBX-NR (EIDEN BTSC );
• Change ADJ from 0 to 1. Check A1 and A2 after 1 second (if they varied);
• After 1 second returns ADJ to 0 . The stereo circuit will align automatically.
ILLUSTRATION
3.6 Vertical Adjustment
• Apply a circle Pattern Philips signal (RF Input)
• Using the remote control, set the MAGIC mode “ORIGINAL”

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• Activate the adjustment mode display (SBL item). Ajust SBL from 0 to 1. Blanking the bottom of
the screen.
• Adjust VSH until the bottom of the pattern be aligned with the reference marks of the mechanical
center on picture tube (the central vertical line in the center of the tube).
• Adjust VS until the central line be aligned with the half bottom of the screen (the central line of the
circle pattern in the half cut of the screen)
• Return SBL from 1 to 0 value . The image could be compressed or expanded.
• Select VA item and set its value to adjust the size of the picture (proportional height and width
picture).
• If necessary readjust SC item and set its value to adjust the Linearity (acts in the top of the image)
and VA.
NOTE: The SC and VA adjustments are interdependent (they should be used together).
When the image to be decentralized in the vertical, to retouch VSH and/or VS
3.7 Horizontal Adjustment
• Apply a Circle Pattern Philips (RF Input)
• Using the remote control, set the MAGIC mode “ORIGINAL”
• Activate the adjustment mode display (HSH item). Select HSH item and set its value to adjust the
horizontal symmetry of the pattern;
• Select HP and HB items and adjust its value if necessary.
3.8 MAGIC Adjustment
• Adjustment of original magic should have been according to pattern
• Receive the color bar pattern (NTSC signal, RF input)
• Connect the oscilloscope probe to the collector of Q830 (cathode G)
• Using the remote control, set the image controls as follow:
Brightness: adjust to central position (8 Bars)
Contrast: adjust from maximum to minimum (4 Bars)
Color: adjust from minimum to maximum (5 Bars)
Sharpness: adjust from minimum to maximum (3 Bars)
Tint: adjust to the center (8 Bars)
• After the image menu preset, turn off the television and activate the service menu. Select
ORIGMAG item;

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• Press “VOLUME +” button and change the value from 0 to 1. Turn off the television and the
ORIGINAL MAGIC setup will be registered.
3.9 “SCREEN ( G2 )” Adjustment
• Apply a Circle Pattern Philips at the antenna terminal (RF Input).
• Using the remote control, set the brightness control to 10 Bars of the bargraph.
• Activate the service mode and select BLKCURR item (the menu value should be 0)
• Turn the Screen Grid Potentiometer (fly back body) fully counterclockwise (minimum adjustment).
• Press the “VOLUME +” button . The register will change to 1 and vertical Deflection will be
blanked.
• Turn the Screen Grid Potentiometer slowly clockwise until the power led (stand by) turn on (if the
adjustment of the screen Grid Potentiometer is turned beyond the ideal point, the power led will be
turn off)
• Press the “VOLUME +” button, it should return the original BLKCURR value. The image will be
return and the adjustment is finished.
3.10 “FOCUS” Adjustment
• Apply a Circle Pattern Philips at the antenna terminal (RF Input).
• Using the remote control, set the Magic mode “ORIGINAL”
• Turn the Focus volume (fly back body) fully counterclockwise once
• Adjust the Focus volume until picture is distinct (center of the screen).

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4 – REMOTE CONTROL
Models CR14300/20300/20310
NOTE: Consult the original r. c. manufacturer documentation to access the schematic
diagram and the replacement parts list.
The “MENU” button contains the following
operations:
MAIN MENU
PICTURE >
S UND >
CHANNEL >
TUNING >
SETUP >

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4 – REMOTE CONTROL
Model CR29411
NOTE: Consult the original r. c. manufacturer documentation to access the schematic
diagram and the replacement parts list.
The “MENU” button contains the following
operations:
MAIN MENU
PICTURE >
S UND >
CHANNEL >
TUNING >
SETUP >

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5.2 – BLOCK DIAGRAM OF IC-101
(
TDA9380
)

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5.3 – BLOCK DIAGRAM OF IC-490 (BU4052)

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5.4 – BLOCK DIAGRAM OF IC-601 (VERTICAL DEFLECTION BOOSTER)
TDA9309/TDA8177F
5.5 – BLOCK DIAGRAM OF IC-401 (STEREO AMPLIFIER) TDA7499

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5.6 – BLOCK DIAGRAM OF IC-450 (STEREO DECODER)

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5.7 – BLOCK DIAGRAM OF IC-430 – LMC568 PLL-“SAP”

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6 – DESCRIPTION OF THE FUNCTIONS – THE INTEGRATED CIRCUIT´S PINS
6.1 – IC101 (TDA9380)
SIGN PIN DESCRIPTION
OPEN 1 N/C
SCL 2 SERIAL CLOCK OUTPUT
DAS 3 SERIAL DATA OUTPUT
GAME 4 GAME (PWM)
SWITCHES A 5 SWITCHES OF THE FRONT PANEL (IN)
SWITCHES B 6 SWITCHES OF THE FRONT PANEL AND LED INDICATION (IN)
VSH DET SVHS DETECTING (IN)
DET SAP 8 SAP DETECTING (IN)
GND 9 TERRA
SW 0 10 COMMUTATION TO EXTERNAL AV
SW 1 11 COMMUTATION TO EXTERNAL AV
GND A 12 GROUND
SEC PLL 13 PLL DECOUPLING (SECAM)
VP 2 14 SUPPLY 2
DEC D05 15 DECOUPLING OF THE DIGITAL PROCESSOR
PH2IF 16 FILTER 2
PH1IF 1 FILTER OF SYNCHRONISM
GND 3 18 GROUND 3
DET BG 19 FILTER OF (BANDGAP)
AVL EWD 20 AVC FILTER
VDR B 21 TO VERTICAL OUTPUT B
VDR A 22 TO VERTICAL OUTPUT A
IF IN 1 23 IF SIGNAL INPUT FILTER S.A.W
IF IN 2 24 IF SIGNAL INPUT FILTER S.A.W
L REF 25 CURRENT INPUT REF. V. DRIVE
VC CAP 26 DECOUPLING OF VERTICAL
AGC 2 FILTER OF AGC
DEEM/SIFIN1 28 SIF 1 INPUT
SDEC SIF 2 29 DECOUPLING OF ÁUDIO (IN 2)
GND2 30 GROUND 2
SNDPLL SIF AGC 31 FILTER OF AGC AND SIF
AVL REF 32 N/C
HOUT 33 OUTPUT OF HORIZONTAL OSC. 15 50HZ
SAND 34 H PULSE SAND CASTLE
ALDEXT OSS AM 35 EXTERNAL AUDIO INPUT IN THE MOD CR14300/20300 – IN THE
OTHERS: N/C
EHT PROT 36 PROTECTION
PLLIF 3 PLL IF FILTER
VIDEOOUT 38 VIDEO OUTPUT
SUPLY 39 SUPPLY
CVBS 40 INPUT OF VIDEO PACKAGE
GND1 41 GROUND
SVHS Y 42 SVHS VIDEO INPUT
SVHS CROMA 43 SVHS CHROME VIDEO INPUT
AUDOUT 44 AUDIO OUTPUT
INS SW2 45 RGB GROUND
ERVIN 46 R-Y GROUND
G2/YIN 4 G-Y GROUND
B2UIN 48 B-Y GROUND

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BCORR/VGUARD 49 ABL
BLYIN 50 BEAM CURRENT
R 51 RED R
G 52 GREEN G
B 53 BLUE B
VDD A 54 SUPPLY
VPE 55 GROUND
VDD C 56 SUPPLY
OSDGND 5 GND OF OSC 12MHZ
XIN 58 CRISTAL OF 12MHZ
XOUT 59 CRISTAL OF 12MHZ
RESET 60 RESET CIRCUIT
VDD P 61 SUPPLY 33V
MUDO 62 MUTE
PW ON 63 POWER
IR 64 IR INPUT
6.2 - IC 901 (TDA16846)
SIGN PIN DESCRIPTION
OTC 1 OFF TIME CIRCUIT
PCS 2 PRIMARY CURRENT SIMULATION
RZI 3 REGULATION AND ZERO CROSSING INPUT
SRC 4 SOFT-STAR AND REGULATION CAPACITOR
OCI 5 OPTO COUPLER INPUT
FC2 6 FAULT COMPARATOR 2 (GND)
SYN SYNCHRONIZATION INPUT
NC 8 NOT CONNECTED
REF 9 REFERENCE VOLTAGE AND CURRENT
FC1 10 FAULT COMPARATOR 1 (GND)
PVC 11 PRIMARY VOLTAGE CHECK
GND 12 GROUND
OUT 13 OUTPUT ( PWM PULSE)
VCC 14 SUPPLY VOLTAGE
6.3 - IC 450 (TDA9855)
SIGN PIN DESCRIPTION
TL 1 TREBLE CONTROL CAPACITOR, LEFT CHANNEL
B1L 2 BASS CONTROL CAPACITOR, LEFT CHANNEL
B2L 3 BASS CONTROL CAPACITOR, LEFT CHANNEL
OUTS 4 OUTPUT SUBWOOFER OR OUTPUT SURROUND SOUND
NC 5 NOT CONNECTED
OUTL 6 OUTPUT, LEFT CHANNEL
LOL INPUT LOUDNESS, LEFT CHANNEL
CAV 10 AUTOMATIC VOLUME CONTROL CAPACITOR
VREF 11 REFERENCE VOLTAGE 0.5 VCC
LIL 12 INPUT LINE, LEFT CHANNEL
FIL 13 INPUT AUTOMATIC VOLUME CONTROL, LEFT CHANNEL
SOL 14 OUTPUT SELECTOR, LEFT CHANNEL
LOL 15 OUTPUT LINE CONTROL, LEFT CHANNEL

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TW 16 CAPACITOR TIMING WIDEBAND FOR DBX
TS 1 CAPACITOR TIMING SPECTRAL FOR DBX
CW 18 CAPACITOR WIDEBAND FOR DBX
CS 19 CAPACITOR SPECTRAL FOR DBX
VEO 20 VARIABLE EMPHASIS OUTPUT FOR DBX
VEI 21 VARIABLE EMPHASIS INPUT FOR DBX
CNR 22 CAPACITOR NOISE REDUCTION FOR DBX
CM 23 CAPACITOR MUTE FOR SAP
CDEC 24 CAPACITOR DC-DECOUPLING FOR SAP
GND 25 GROUND
SDA1 26 SERIAL DATA INPUT/OUTPUT (I2C-BUS)
SCL 2 SERIAL CLOCK INPUT (I2C-BUS)
VCC 28 SUPPLY VOLTAGE
COMP 29 COMPOSITE INPUT SIGNAL
VCAP 30 CAPACITOR FOR ELECTRONIC FILTERING OF SUPPLY
CP1 31 CAPACITOR FOR PILOT DETECTOR
CP2 32 CAPACITOR FOR PILOT DETECTOR
CPH 33 CAPACITOR FOR PHASE DETECTOR
CADJ 34 CAPACITOR FOR PILTER ADJUSTMENT
CER 35 CERAMIC RESONATOR ( 503KHz)
CMO 36 CAPACITOR DC-DECOUPLING MONO
CSS 3 CAPACITOR DC-DECOUPLING STEREO/SAP
LOR 38 OUTPUT LINE CONTROL, RIGHT CHANNEL
SOR 39 OUTPUT SELECTOR, RIGHT CHANNEL
AVR 40 INPUT AUTOMATIC VOLUME CONTROL, RIGHT CHANNEL
LIR 41 INPUT LINE CONTROL, RIGHT CHANNEL
CPS2 42 CAPACITOR 2 PSEUDO FUNCTION
CPS1 43 CAPACITOR 1 PSEUDO FUNCTION
EOR 44 OUTPUT EFFECTS, RIGHT CHANNEL
VIR 45 INPUT VOLUME CONTROL, RIGHT CHANNEL
LDR 46 INPUT LOUDNESS, RIGHT CHANNEL
OUTR 4 OUTPUT, RIGHT CHANNEL
NC 48 NOT CONNECTED
SW 49 FILTER CAPACITOR FOR SUBWOOFER
B2R 50 BASS CONTROL CAPACITOR, RIGHT CHANNEL
B1R 51 BASS CONTROL CAPACITOR, RIGHT CHANNEL
TR 52 TREBLE CONTROL CAPACITOR
6.4 - IC 490 (4052)
SIGN PIN DESCRIPTION
IN1A 2Y0 1 REAR AV 1 INPUT (R) JUST TO CR20310/29411
IN3A 2Y2 2 REAR AV 1 INPUT (R) JUST TO CR20310/29411
OUTA 2Z 3 OUTPUT OF L/R JUST TO CR20310/29411
IN4A 2Y3 4 FRONT AV 2 INPUT (R) JUST TO CR20310/29411
IN2A 2Y1 5 FRONT AV 3 INPUT (R) JUST TO 29411
INIBIT E 6 GROUND
VEE VEE GROUND
VSS GND 8 GROUND
CTL2 G1 9 SW 1 SWITCH
CTL1 S0 10 SW 0 SWITCH
IN4B 1Y3 11 FRONT (L) INPUT
IN1B 1Y0 12 SAP INPUT

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OUTB 1Z 13 OUTPUT
IN2B 1Y1 14 AV3 ( L) INPUT TO CR29411 AND VIDEO INPUT TO CR14300/20300
IN3B 1Y2 15 AV1 ( L) INPUT TO CR20310/29411 - AUDIO INPUT TO CR14300/20300
VDD VCC 16 SUPPLY VOLTAGE
6.5 – IC102 (M24CO4MN)
SIGN PIN DESCRIPTION
AO 1 GROUND
A1 2 GROUND
A2 3 GROUND
VSS 4 GROUND
DAS 5 SERIAL DATA
SCL 6 SERIAL CLOCK
TEST GROUND
VDD 8 SUPPLY VOLTAGE
6.6 - IC 601 (TDA9309) 14” 20” (TDA8177F) 29”
SIGN PIN DESCRIPTION
Idrive (neg) 1 NON-INVERTING INPUT
VCC 2 SUPPLY VOLTAGE (12V)
Vp 3 FLYBACK GENERATOR
GND 4 GROUND
OUT 5 OUTPUT
REF 6 OUTPUT STAGE SUPPLY
Idrive (pos) INVERTING INPUT
6.7 - IC 401 (TDA7499)
SIGN PIN DESCRIPTION
Vs- 1 DC SUPPLY VONTAGE
OUTR 2 OUTPUT RIGHT CHANNEL
VS+ 3 DC SUPPLY VOLTAGE (12V)
OUTL 4 OUTUPUT LEFT CHANNEL
MUTE 5 MUTE
Vs- 6 DC SUPPLY VONTAGE (-12V)
IN+ INPUT
IN- 8 INPUT
GND 9 GROUND
IN- 10 INPUT
IN+ 11 INPUT

7.0 - OPERATION DESCRIPTION TELEVISION SET CIRCUIT
Fig.1- Block diagram
Speaker
CRT
The block diagram in Fig.1 shows how the TV set circuit works divided into basic circuits.
7.1 - POWER SUPPLY
IC901, IC902, IC903, T901, Q901 and surrounding components (9xx)
This is a switching mode power supply designed to operate in AC power source from 99 Volts to 242 Volts
and 50/60 Hertz.
The main device is the TDA16 46 (controller for switching mode power supplies).
There are two different operating modes, low power standby and full operation mode.
-Standby: The power supply works in the burst mode and the circuit turn-on during 2 ms and turn-off
during 12 ms. In this mode the power consumption is less than 2 Watts in 120 V AC and less than 3 Watts in
220 V AC. In the burst mode, the output voltages are reduced to 10% of the normal values (except
microprocessor supply voltage) .
-Full operation mode: This mode is activate by the microprocessor (Remote control or front panel). The
output voltages regulation is controlled by the IC903 circuit, opto coupler feedback (IC902) and by the IC901.
The basic output voltages are:
1. 10 /12 Volts (CR14300_20300/CR20310_29411) to horizontal circuit;
2. +12 and –12 Volts to audio and vertical circuits;
3. 9 Volts to TV signal processor, stereo decoder and AV circuits;
4. 5 Volts to microprocessor and memory circuits;
5. 3.3 Volts to microprocessor and front panel switches circuits.
There are 3 basic protection mode:
1. AC power source undervoltage: the power supply will turn-off when the AC source is less than 95 Volts.
2. Power consumption limit: when the power consumption exceed 20% of the normal value.
3. Overvoltage outputs shutdown: when the output voltages exceed 15% of the normal values.
7.2 - TV SIGNAL PROCESSOR + MICROPROCESSOR
IC101, IC102 and surrounding components (1xx)
The main device is the TDA93 0 (TV signal processor-Teletext decoder with embedded Micro-Controller)
that combines the functions of a TV signal processor together with a Micro Controller and Closed Caption
decoder. The highlights of this device are:
3.Tuner
4. AV
switches
1. Power Supply
2. TV signal processor
and Microprocessor
Circuit
5. Stereo
decoder
7.Video
output
.Horizontal
and vertical
deflections
6.Audio
output
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