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S/M No. : TCP785AEF0
Service Manual
59/68 Cm STEREO Color Television
MODEL CHASSIS
DTE-25G5THS CP-785A
DTE-29G5TH
FS-59T90 CP-785A
FS-68T90
DAEWOO ELECTRONICS CO., LTD.
http : //svc.dwe.co.kr NOV. 2000
Service manual CP-785A
Contents
1 - Main features ................................................................................................................................. 2
1-1 Specifications .................................................................................................................... 2
1-2 Channel table .................................................................................................................... 4
2 - Safety instruction .......................................................................................................................... 7
3 - Alignment instructions ................................................................................................................. 8
3-1 Microcontroller configuration : Service mode .................................................................... 8
3-2 Microcontroller configuration : Option................................................................................ 8
3-3 TV set Alignment ............................................................................................................... 8
4 - IC description ................................................................................................................................ 10
4-1 TDA936x TV signal processor - TXT with embedded m-Controller. .................................. 10
4-2 MSP3415D Multistandard Sound Processor ..................................................................... 18
4-3 TDA894xJ Stereo Audio Amplifier..................................................................................... 22
4-4 TDA835xJ Vertical Amplifier.............................................................................................. 23
4-4-1 TDA8358J............................................................................................................... 24
4-5 TDA6107Q ........................................................................................................................ 25
4-6 24C08 8 Kbit EEPROM ..................................................................................................... 26
4-7 STR-F6654 ....................................................................................................................... 27
5 - Circuit description......................................................................................................................... 29
5-1 Block diagram.................................................................................................................... 29
5-2 IF ....................................................................................................................................... 33
5-3 Source switching ............................................................................................................... 34
5-4 u-Controller I/O pin configuration and function.................................................................. 34
5-5 Sound processing.............................................................................................................. 35
5-6 Sound amplification ........................................................................................................... 37
5-7 Vertical deflection .............................................................................................................. 37
5-8 Power supply (STR-F6654) ............................................................................................... 39
5-9 TV start-up, TV normal run and stand by mode operations .............................................. 43
6 -Service parts list............................................................................................................................. 50
FS-59T90 & FS-68T90 ........................................................................................................... 50
(DTE-25G5THS & DTE-29G5TH)
7 - Exploded view ............................................................................................................................... 59
8 - PCB Layout .................................................................................................................................... 61
9 - Circuit Diagram.............................................................................................................................. 62
Service manual CP-785A
1-1 Specifications
TV standard PAL, SECAM - B/G, H
Sound system NICAM B/G
FM 2Carrier B/G
Power consumption 25" : 113 W approx.
29" : 118 W approx.
Sound Output Power 25" : 5W x 5W (at 60% mod, 10%THD)
29" : 5W x 5W (at 60% mod, 10%THD)
Speaker 25" : 7W 8 ohm x 2
29" : 7W 8 ohm x 2
Teletext system 10 pages memory FASTEXT (FLOF or TOP)
Aerial input 75 ohm unbalanced
Channel coverage Off-air channels, S-cable channels and hyperband
Tuning system frequency synthesiser tuning system
Visual screen size 25" : 59 cm
29" : 68 cm
Channel indication On Screen Display
Program Selection 100 programmes
Aux. terminal INPUT1(SCART) : Audio / Video In, S-VHS In(with cable)
INPUT2(RCA) : Audio / Video In
OUTPUT(RCA) : TV OUT
Headphone jack (3.5 mm) on front of cabinet
Remote Control Unit R-40A01 / R-44N08(RD-D90)
RCA Jack - input 2
Pin Signal Description Matching value
1 Video Input 1.0 Vpp+/- 3dB , Impedance 75 ohm
2 Audio Input Left 0.5 Vrms, Impedance > 10k ohm
3 Audio Input Right 0.5 Vrms, Impedence > 10k ohm
-2-
Service manual CP-785A
RCA Jack output
Pin Signal Description Matching value
1 TV Video 1.0Vpp +/- 3dB , Impedence 75 ohm
2 TV Audio Left 0.5Vrms at RF sound FM 54% Mod.(27kHz dev.)
3 TV Audio Right 0.5Vrms at RF sound FM 54% Mod.(27kHz dev.)
W
W
W
W
21 pin Euro SCART - Input 1 / S-Video
Pin Signal Description Matching value
1 N.C.
2 Audio Input Right 0.5 Vrms, Impedance > 10 kW
3 N.C.
4 Audio Earth
5 Earth
6 Audio Input Left 0.5 Vrms, Impedance > 10 kW
7 N.C.
8 N.C.
9 N.C.
10 N.C.
11 N.C.
12 N.C.
13 N.C
14 Earth
15 Chroma Input +/- 3dB for a luminance signal of 1 Vpp
16 N.C.
17 Earth
18 Video In Earth
19 N.C.
20 Video Input / Y Input 1 Vpp +/- 3dB, Impedance 75 ohm
21 Common Earth
-3-
Service manual CP-785A
1-2 Channel table
FREQUENCY TABLE CP-785A
CH AUSTRALIA N/Z'land
C00 46.25
C01 57.25
C02 64.25
C03 86.25
C04 95.25
C05 102.25
C5A 138.25
C06 175.25
C07 182.25
C08 189.25
C09 196.25
C10 209.25
C11 216.75
N01 - 45.25
N02 - 55.25
N03 - 62.25
N08 - 203.25
N09 - 210.25
N10 - 217.25
- - - - -
C21 471.25
C22 479.25
C23 487.25
C24 495.25
C25 503.25
C26 511.25
C27 519.25
C28 527.25
C29 534.25
C30 541.25
C31 548.25
C32 555.25
C33 562.25
C34 569.25
C35 576.25
C36 583.25
C37 590.25
C38 597.25
C39 603.25
C40 610.25
C41 617.25
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Service manual CP-785A
CH AUSTRALIA N/Z'land
C42 624.25
C43 631.25
C44 638.25
C45 645.25
C46 652.25
C47 659.25
C48 666.25
C49 673.25
C50 680.25
C51 687.25
C52 694.25
C53 701.25
C54 708.25
C55 715.25
C56 722.25
C57 729.25
C58 736.25
C59 743.25
C60 750.25
C61 757.25
C62 764.25
C63 771.25
C64 779.25
C65 786.25
C66 793.25
C67 800.25
C68 807.25
C69 814.25
C70 -
C71 -
C72 -
C73 -
C74 -
C75 -
C76 -
C77 -
S01 105.25
S02 112.25
S03 119.25
S04 126.25
S05 133.25
S06 140.25
S07 147.25
S08 154.25
S09 161.25
-5-
Service manual CP-785A
CH AUSTRALIA N/Z'land
S10 168.25
S11 231.25
S12 238.25
S13 245.25
S14 252.25
S15 259.25
S16 266.25
S17 273.25
S18 280.25
S19 287.25
S20 294.25
S21 303.25
S22 311.25
S23 319.25
S24 327.25
S25 335.25
S26 343.25
S27 351.25
S28 359.25
S29 367.25
S30 375.25
S31 383.25
S32 391.25
S33 399.25
S34 407.25
S35 415.25
S36 423.25
S37 431.25
S38 439.25
S39 447.25
S40 455.25
S41 463.25
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Service manual CP-785A
2 - Safety instruction
WARNING: Only competent service personnel may carry out work involving the testing or repair of
this equipment.
X-RAY RADIATION PRECAUTION
1. Excessive high voltage can produce potentially hazardous X-RAY RADIATION. To avoid
such hazards, the high voltage must not exceed the specified limit. The nominal value of the high
voltage of this receiver is 26~28 KV (25" - 29") at max beam current. The high voltage must not
under any circumstances, exceed 29.5 KV (25") or 31 KV (29").
Each time a receiver requires servicing, the high voltage should be checked. It is important to
use an accurate and reliable high voltage meter.
2. The only source of X-ray Radiation in this TV receiver is the picture tube. For continued X-ray
RADIATION protection, the replacement tube must be exactly the same type tube as specified
in the parts list.
SAFETY PRECAUTION
1. Potentials of high voltage are present when this receiver is operating. Operation of the receiver
outside the cabinet or with the back board removed involves a shock hazard from the receiver.
1) Servicing should not be attempted by anyone who is not thoroughly familiar with the
precautions necessary when working on high voltage equipment.
2) Discharge the high potential of the picture tube before handling the tube. The picture tube is
highly evacuated and if broken, glass fragments will be violently expelled.
2. If any Fuse in this TV receiver is blown, replace it with the FUSE specified in the Replacement
Parts List.
3. When replacing a high wattage resistor (oxide metal film resistor) in circuit board, keep the resistor
10 mm away from circuit board.
4. Keep wires away from high voltage or high temperature components.
5. This receiver must operate under AC 240 volts, 5O Hz. NEVER connect to DC supply or any
other power or frequency.
PRODUCT SAFETY NOTICE
Many electrical and mechanical parts in this equipment 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 replacement components rated for
higher voltage, wattage, etc. Replacement parts which have these special safety characteristics are
identified in this manual and its supplements, electrical components having such features are identified
by designated symbol on the parts list. Before replacing any of these components, read the parts list in
this manual carefully. The use of substitutes replacement parts which do not have the same safety
characteristics as specified in the parts list may create X-ray Radiation.
-7-
Service manual CP-785A
3 - Alignment instructions
3-1 Microcontroller configuration : Service mode
To switch the TV set into service mode please see instruction below.
1 - Select pr. number 91
2 - Adjust sharpness to minimum value and exit all menu.
3 - Quickly press the key sequence : RED - GREEN - menu
To exit SERVICE menu press menu key or Operate(Std By) key.
In Service Mode press "OK" to stop the microcontroller i.e. the I2C bus is free and the set can be
controlled by external equipment. Press "OK" again to allow the microcontroller to control the set
again
3-2 Microcontroller configuration : Option
Option Tuner maker Remark
0 DAEWOO / SAMSUNG for Daewoo Remote control
1 DAEWOO / SAMSUNG for Daewoo Remote control
4 DAEWOO / SAMSUNG for NEC Remote control
5 DAEWOO / SAMSUNG for NEC Remote control
3-3 TV set Alignment
3-3-1 - G2 alignement
- TV in AV mode without video signal Black screen.
- TV preset with WP Red, WP Green and WP Blue equal to 32.
- TV preset with Black R, Black G equal to 8.
- Set TV in NORMAL I mode
- Adjust screen volume ( on FBT ) such that the highest cathod cut-off voltage measured on CRT
board, is Vcut off