Universum FT-81031 User manual
SERVICE MANUAL
UNIVERSUM FT-81031
MODEL
1
CONTENTS
Safety Precautions ........................................................................................................................................... 2
TV Set switched off ........................................................................................................................................... 2
Measurements ................................................................................................................................................. 2
PERI -TV SOCKET ............................................................................................................................................ 2
SC RT 1, SC RT 2 .......................................................................................................................................... 2
INTRODUCTION .............................................................................................................................................. 2
SWITCH-MODE POWER SUPPLY (TD 16846) .............................................................................................. 3
IF P RT (TD 4470/72) ..................................................................................................................................... 3-4
TUNER ............................................................................................................................................................. 4-5
S W FILTERS ................................................................................................................................................... 5
DIGIT L TV SOUND PROCESSING (MSP 3410D) .......................................................................................... 5-6
DOLBY PRO LOGIC PROCESSOR IC (DPL 3519 ) ....................................................................................... 6-7
HE DPHONE OUTPUT (TD 1308) ................................................................................................................ 7
VIDEO OUTPUT (TD 7265) ............................................................................................................................ 7-8
VIDEO INPUT ND OUTPUT SOURCE SWITCHING (TE 6415) ................................................................... 8
VIDEO OUTPUT MPLIFIER ST GE (TD 6111Q) ........................................................................................... 8-9
VERTIC L OUTPUT ST GE (TD 9379F ) ...................................................................................................... 9
TTEXT CONTROLLER (SD 5550M) ............................................................................................................... 9-10
SERI L CCESS 32K EEPROM (24L32-W) .................................................................................................... 10-11
EPROM (M27W401) ......................................................................................................................................... 11
100Hz FE TURE BOX ...................................................................................................................................... 11
VPC32X5 (VIDEO PROESSOR) ................................................................................................................. 11
CIP3250 ...................................................................................................................................................... 12-13
SD 9400 ..................................................................................................................................................... 13-14-15
DDP3310 .................................................................................................................................................... 15-16
K41 CH SSIS M NU L DJUSTMENTS PROCEDURE ............................................................................... 17
PRELIMIN RY ............................................................................................................................................. 17
SYSTEM VOLT GE JUSTMENT ................................................................................................................ 17
FC DJUSTMENT ..................................................................................................................................... 17
FOCUS DJUSTMENT ................................................................................................................................17
SCREEN DJUSTMENT ............................................................................................................................. 17
IF DJUSTMENT FOR LMODE ................................................................................................................... 17
K41 CH SSIS PRODUCTION MODE DJUSTMENTS PROCEDURE ......................................................... 18
PRELIMIN RY ............................................................................................................................................. 18
HORIZONT L ND VERTIC L GEOMETRY LIGNMENTS ........................................................................ 18
V-SHIFT ....................................................................................................................................................... 18
V-SIZE .......................................................................................................................................................... 18
H-SHIFT ...................................................................................................................................................... 18
H-SIZE ......................................................................................................................................................... 18
S-COR ......................................................................................................................................................... 18
LINRT .......................................................................................................................................................... 18
NGLE ........................................................................................................................................................ 18
BOW ... ........................................................................................................................................................ 18
TRPEZ ......................................................................................................................................................... 18
P R B ......................................................................................................................................................... 18
U.COR ......................................................................................................................................................... 19
L.COR ......................................................................................................................................................... 19
VIDEO LIGNMENTS ........................................................................................................................................ 19
RGn, GGn, BGn,:WHITE B L NCE DJUSTMENT .................................................................................... 19
RRf, GRf, BRf .............................................................................................................................................. 19
YDF . ........................................................................................................................................................... 19
GC . .......................................................................................................................................................... 19
TL N . .......................................................................................................................................................... 19
PS . ........................................................................................................................................................... 19
T_T ............................................................................................................................................................ 19
T_P ............................................................................................................................................................ 19
EXT3 ............................................................................................................................................................ 19
CLT ............................................................................................................................................................ 19
SERVICE LIGNMENTS ................................................................................................................................... 20
IMPORT NT ................................................................................................................................................ 20
DJUSTMENTS GROUOP .......................................................................................................................... 20
OPTIONS GROUP ...................................................................................................................................... 20
SYSTEM GROUP ........................................................................................................................................ 20
GENER L BLOCK DI GR M OF CH SSIS K41 ........................................................................................... 21
CIRCUIT DI GR MS ........................................................................................................................................ 22
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DO NOT CHANGE ANY MODULE UNLESS THE SET IS SWITCH OFF
The mains supply side of the switch mode power supply transformer is live.
Use an isolating transformer.
The receivers fulfill completely the safety requirements.
Safety precautions
Servicing of this TV should only be carried out by a qualified person.
- Components marked with the warning symbol on the circuit diagram are critical for safety and must only be replaced
with an identical component.
- ower resistor and fusable resistors must be mounted in an identical manner to the original component.
- When servicing this TV, check that the EHT does not exceed 26kV.
TV Set switched off
Make short-circuit between HV-CRT clip and CRT ground layer.
Short C804 (150mF) before changing IC802 or other components in primary side of SM S.
Measurements
Voltage readings and oscilloscope traces are measured under following conditions.
Antenna signal 60dB from colourbar generator. (100% white, 75% colour saturation)
Brightness, contrast, colour set for a normal picture.
Mains supply, 220VAC, 50Hz.
PERI-TV SOCKET
SCART 1 (SC050) SCART 2 (SC051)
1 Audio right output 0.5Vrms / 1K 1 Audio right output 0.5Vrms / 1K
2 Audio right input 0.5Vrms / 10K 2 Audio right input 0.5Vrms / 10K
3 Audio left output 0.5Vrms / 1K 3 Audio left output 0.5Vrms / 1K
4 Ground AF 4 Ground AF
5 Ground Blue 5 Ground Blue
6 Audio left input 0.5Vrms / 10K 6 Audio left input 0.5Vrms / 10K
7 Blue input 0.7Vpp / 75ohm 7 Blue input 0.7Vpp / 75ohm
8 AV switching input 0-12VDC /10K 8 AV switching input 0-12VDC /10K
9 Ground Green 9 Ground Green
10 - 10 -
11 Green input 0.7Vpp / 75ohm 11 -
12 - 12 -
13 Ground Red 13 Ground Red
14 Ground Blanking 14 Ground Blanking
15 Red input 0.7Vpp / 75ohm 15 -
16 Blanking input 0-0.4VDC, 1-3VDC / 75ohm 16 -
17 Ground CVS output 17 Ground CVS output
18 Ground CVS input 18 Ground CVS input
19 CVS output 1Vpp / 75ohm 19 CVS output 1Vpp / 75ohm
20 CVS input 1Vpp / 75ohm 20 CVS input 1Vpp / 75ohm
21 Ground 21 Ground
INTRODUCTION
11Ak41 is a 100Hz flicker free colour television capable of driving 284:3/16:9, 334:3 and 294:3 real flat picture tubes.
The chassis is capable of operation in AL, SECAM, NTSC (playback) colour standards and multiple transmission standards
as B/G, D/K, I/I, and L/L´.
Sound system output is supplying 12W (10%THD) for left, right and center outputs of 8ohm speakers, and 2 x 7W for surround
outputs of 2 x 4ohm speakers, connected in series.
TV supports the level 1.5 teletext standard. It is possible to decode transmissions including high graphical data.
The chassis is equipped with one full EuroScart, one other SCART for AV input/output, one front-AV input, one back-AV
output, one headphone output, one SVHS input (via SCART and SVHS connector), one VGA input, two external speaker
outputs (left and right), one centre speaker output, and one surround speaker output for two speakers in series.
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SWITCH-MODE POWER SUPPLY (TDA16846)
A SM S transformer controlled by the IC TDA16846, which is designed for driving, controlling, and protecting switching
transistor, provides the DC voltages required at various parts of the chassis. SM S generates the necessary 3.3V and 2.5V
supplies for the micro-controller, 130V supply for the FBT, +/-16V supply for the audio amplifier, which are active in stand-by
and 8V, 12V and 5V supplies for other different parts of the chassis.
When the TV is switched on, a reference voltage is provided to TDA16846 and the start-up operation occurs, then TV
enters into the stand-by position.
Two optocouplers are used to control the regulation of line voltage and stand-by power consumption. There are two regula-
tion circuits, one in primary side and one in secondary side. The primary regulation circuit provides a control voltage to pin3
of the IC. Secondary regulation circuit produces a control voltage according to the changes in 130V DC voltage, via an
optocoupler (SFH617A) to pin4 of the IC.
During the switch on period of the transistor, energy is stored in the transformer. During the switch off period energy is fed
to the load via secondary winding. By varying switch-on time of the power transistor, it controls each portion of energy
transferred to the second side such that the output voltage remains nearly independent of load variations. At the same time,
the supply voltages 12V, 8V, 5V are stabilised by the series regulators.
Features
nLine Current Consumption with FC
nContinuous Frequency Reduction with Decreasing Load
nStable and Adjustable Stand-by Frequency
nVery Low Start-up Current
nSoft-Start for Quiet Start-up
nAdjustable and Voltage Dependent Ringing Suppression Time
nSynchronization and Fixed Frequency Facility
nOver- and Under-voltage Lockout
nSwitch Off at Mains Under-voltage
nMains Voltage Dependent Fold Back oint Correction
nLow ower Consumption
nFree usable Fault Comparators
Pinning
1. OTC Off Time Circuit
2. CS rimary Current Simulation
3. RZI Regulation and Zero Crossing Input
4. SRC Soft-Start and Regulation Capacitor
5. OCI Opto Coupler Input
6. FC2 Fault Comparator 2
7. SYN Synchronization Input
8. N. C. Not Connected
9. REF Reference Voltage and Current
10. FC1 Fault Comparator 1
11. VC rimary Voltage Check
12. GND Ground
13. OUT Output
14. VCC Supply Voltage
IF PART (TDA4470/72)
The TDA44XX is an integrated bipolar circuit for multistandard video/sound IF (VIF/SIF) signal processing in TV/VCR
and multimedia applications. The circuit processes all TV video IF signals with negative modulation (e.g., B/G standard),
positive modulation (e.g., L standard) and the AM, FM/NICAM sound IF signals. Active carrier generation by F LL (fre-
quency phase-locked loop) is the principle for true synchronous demodulation. VCO circuit is operating on picture carrier
frequency, the VCO frequency is switchable for L´-mode. AFC without external reference circuit is alignment-free and
polarity of the AFC curve is switchable. VIF-AGC for negative modulated signals operates on peak sync detection principle
and for positive modulation on peak white / black level detection principle. Tuner AGC is adjustable with determining take
over point. It has alignment-free quasi-parallel sound (Q S) mixer for FM/NICAM sound IF signals. Intercarrier output sound
is gain controlled (necessary for digital sound processing). AM-demodulator is completely alignment-free with gain control-
led AF output. Operation of the AM demodulator and Q S mixer (for NICAM-L stereo sound is parallel. TDA4472 is used for
negative modulation and TDA4470 is used for both negative and positive modulation.
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Features
n5V supply voltage; low power consumption
nActive carrier generation by F LL principle (frequency-phase-locked-loop) for true synchronous demodulation
nVery linear video demodulation, good pulse response and excellent intermodulation figures
nVCO circuit is operating on picture carrier frequency, the VCO frequency is switchable for the L mode
nAlignment-free AFC without external reference circuit, polarity of the AFC curve is switchable
nVIF-AGC for negative modulated signals (peak sync detection) and for positive modulation
(peak white/black level detector).
nTuner AGC with adjustable take over point
nAlignment-free quasi parallel sound (Q S) mixer for FM/NICAM sound IF signals
nIntercarrier output signal is gain controlled (necessary for digital sound processing)
nComplete alignment-free AM demodulator with gain controlled AF output
nSeparate SIF-AGC with average detection
nTwo independent SIF inputs
narallel operation of the AM demodulator and Q S mixer (for NICAM-L stereo sound)
nackage and relevant pinning is compatible with the single standard version TDA 4472; simplifies the design of
an universal IF module
Pinning
1. Input sensitivity, RMS value : 80mVrms
2. Input sensitivity, RMS value : 80mVrms
3. SIF Input selector switch : 2.0 V
4. Ground
5. IF gain control range : 65dB
6. Input sensitivity, RMS value : 80mVrms
7. Input sensitivity, RMS value : 80mVrms
8. IF gain control range : 65dB
9. Ground
10. Available tuner-AGC current : 2mA
11. Available tuner-AGC current : Min : 0.3V Max : 13.5V
12. Video output : Min : 1.8V Max : 2.2V
13. Standard switch : Min : 0V Max : 0.8V
14. L switch : Min : 0V Max : 3.0V
15. IF gain control range : 65dB
16. Ground
17. Internal reference voltage
18. F LL and VCO : Min : 1mA Max : 4mA
19. AFC switch : Min : 0V Max : 0.8V
20. F LL and VCO : Min : 1mA Max : 4mA
21. F LL and VCO : Min : 1mA Max : 4mA
22. AFC output : 0.7 mA/kHz
23. DC supplay : Min : 4.5V Max : 9.0V
24. DC output voltage : 2V
25. AF output-AM : 2.2V
26. F LL and VCO : Min : 1mA Max : 4mA
27. Input sensitivity, RMS value : 80mVrms
28. Input sensitivity, RMS value : 80mVrms
TUNER
The hardware and software of the TV is suitable for tuners, supplied by different companies, which are selected from the
Service Menu. These tuners can be combined VHF, UHF tuners suitable for CCIR systems B/G, H, L, L´, I/I´, and D/K.
The tuning is available through the digitally controlled I²C bus ( LL). Below you will find info on one of the Tuners in use.
General description of UV1316
The UV1316 tuner belongs to the UV 1300 family of tuners, which are designed to meet a wide range of applications. It is a
combined VHF, UHF tuner suitable for CCIR systems B/G, H, L, L, I and I. The low IF output impedance has been designed
for direct drive of a wide variety of SAW filters with sufficient suppression of triple transient.
Features of UV1316
nMember of the UV1300 family small sized UHF/VHF tuners
nSystems CCIR: B/G, H, L, L, I and I; OIRT: D/K
nDigitally controlled ( LL) tuning via I2C-bus
nOff-air channels, S-cable channels and Hyperband
nWorld standardised mechanical dimensions and world standard pinning
nCompact size
nComplies to CENELEC EN55020 and EN55013
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