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SM-142
R
Service Manual - SM-142
CONTENTS PAGE
Safety Instructions 1
Technical Specifications 2
Instructions Manual 4
Pin Voltages of IC's 15
Pin Voltages of Some Transistors 18
Oscillograms 19
Electrical and Service Adjustments 21
Trouble Shooting Guide 24
Convergence Adjustments 31
Channel Frequency Tables 33
Part List 37
Circuit Diagrams Attached
PIN VOLTAGES OF IC'S
IC101 (TDA956X H)
TV signal processor-Teletext Decoder with embedded u-Controller
Pin Connection V DC (*) Pin Connection V DC (*)
1 Volume +/- 3,2 (3,2) 41 Gnd for TV processor 0 (0)
2 Status 1 0 (0) 42 External CVBS input 0 (0)
3 Status 2 0 (0) 43 Gnd for TV processor 0 (0)
4 Digital ground for u-controller 0 (0) 44 SVHS-Y input 3.35 (0)
5 Not connected 0.75 (0.25) 45 SVHS-C input 0 (0)
6 Standby on/off 0.01 (3.9) 46 White stretch capacitor 3.4 (0)
7 Analog Gnd of text decoder and dig Gnd of TV 0 (0) 47 CVBS output 2.8 (0.07)
processor
8 Secam PLL decoupling 2.3 (0) 48 Audio output/AM audio output 3.45 (0)
9 2nd supply voltage TV proc (8V) 8.0 (0.26) 49 2nd IF video output (not conn.)
10 Supply volt.deccoup. of dig. Gnd of TV 5.0 (0) 50 2nd RGB / YUV insertion input 0.17 (0)
processor
11 Phase 2 filter 2.73 (0) 51 Red input 2.6 (0)
12 Phase 1 filter 3.9 (0) 52 Green input 2.6 (0)
13 Gnd 3 for TV processor 0 (0) 53 Blue input 2.6 (0)
14 Decoupling bandgap 4.0 (0) 54 Beam current limiter input 2.6 -3.4 (0)
15 AVL (90 versions) / East/West drive signal (110 3.0 (0.5) 55 Black current input / V-guard input 4.6-5.7 (0)
versions)
16 V-drive B output 1.0 (0) 56 Red output see oscilog.
17 V-drive A output 1.0 (0) 57 Green output see oscilog.
18 IF-1 input 1.87 (0) 58 Blue output see oscilog.
19 IF-2 input 1.87 (0) 59 Analog supply of text decoder and 3.3 (3.3)
dig.supply of TV proc (3.3V)
20 Reference current input 3.9 (0) 60 OTP programming voltage 0 (0)
21 Vertical sawtooth capacitor 3.8 (0) 61 Dig. Supply to core (3.3V) 3.3 (3.3)
22 Tuner AGC output 4.3 (0) 62 X-tal Gnd 0 (0)
23 Sound IF input 1 1.9 (0) 63 X-tal input
24 Gnd 0 (0) 64 X-tal output
25 Gnd 0 (0) 65 Programming Reset (not connected) 0 (0)
26 Norrow band PLL filter 2.2 (0) 66 Dig. Supply to periphery (3.3V) 3.3 (3.3)
27 AVL (Automatic Vol. Levelling) 0.42 (0.08) 67 SCL1 (Eeprom) 3.3 (3.3)
28 Ext. Audio (audio 2) input 3.73 (0.08) 68 SDA1 (Eeprom) 3.3 (3.3)
29 Audio 3 input (not connected) 3.73 (0.09) 69 IR input 3.3 (3.3)
30 H-drive output 2.33 (0.26) 70 Not connected
31 Sandcastle output-Hor.Fly.input 0.56 (0.25) 71 SCL see oscilog.
32 Decoupling sound demodulator 2.0 (0) 72 SDA see oscilog.
33 QSS intercarrier output / AM output 3.43 (0.3) 73 MSP reset (IC301) 4.9 (0)
34 EHT / overvoltage protection input 2.2 (0.08) 74 Mute 0 (3.3)
35 IF-PLL loop filter 2.45 (0) 75 SVHS switching 3.3 (3.3)
36 Sound IF AGC 0.5 (0) 76 L/L' switching 3.3 (3.3)
37 QSS output 0.6 (0) 77 F Blank MM Not conn. 3.3 (3.3)
38 IF video / selected CVBS output 3.0 (0) 78 Program + 3.3 (3.3)
39 main supply voltage TV processor 8.0 (0.25) 79 CVBS sync filter 3.3 (1.8)
40 Internal CVBS input 3.8 (0) 80 Program - 3.3 (3.3)
(*) Standby values are given in parenthesis
Note: The function of pin 15, 27, 33 and 48 is dependent on the mode of operation (mono intercarrier mode / QSS IF amplifier
and East-West output or not) and is controlled by some software control bits.
IC 301- MULTI STANDARD SOUND PROCESSOR (MSP 3400D)
Pin Connection V DC Pin Connection V DC
1 Not connected 33 Scart 2 sound output (R) 3.7
2 Gnd 0 34 Scart 2 sound output (L) 3.7
3 Gnd 0 35 Gnd 0
4 Gnd 0 36 Scart 1 sound output (R) 3.7
5 Gnd 0 37 Scart 1 sound output (L) 3.7
6 Gnd 0 38 Volume capacitor Main
7 Supply 4.9 39 Analog Supply 8
8 Supply 4.9 40 Volume capacitor Aux
9 SCL 2.4-2.6 41 Gnd 0
10 SDA 1.8-2.1 42 Analog ref. supply 3.7
11 Not connected 2.4 43 Scart 4 input (L) 3.7
12 Not connected 2.4 44 Scart 4 input (R) 3.7
13 Not connected 2.4 45 Gnd 0
14 Not connected 4.9 46 CINCH - sound input (L) 3.7
15 Not connected 0.7 47 CINCH - sound input (R) 3.7
16 Not connected 0.7 48 Gnd 0
17 Not connected 0.7 49 Scart 2 sound input (L) 3.7
18 Supply 4.9 50 Scart 2 sound input (R) 3.7
19 Gnd 0 51 Gnd 0
20 Not connected 0.7 52 Scart 1 input (R) 3.7
21 Gnd 0 53 Scart 1 input (L) 3.7
22 Gnd 0 54 A/D converter ref. Voltage 2.5
23 Gnd 0 55 Mono sound input 3.7
24 MSP, RESET 4.9 56 Gnd 0
25 Headphone sound output (R) 2.1 57 Analog Supply 4.9
26 Headphone sound output (L) 2.1 58 IF input 1 1.5
27 Gnd 0 59 - 1.5
28 R-out 0.1-2.1 60 IF input 2 0
29 L-out 0.1-2.1 61 Gnd 0
30 Dolby on (C) 0.1-2.1 62 Crystal oss. input 2.3
31 Dolby on (SUB) 0.1-2.1 63 Crystal oss. output 2.3
32 Dolby on (S) 0 64 Gnd 0
IC303, IC304 Audio Output IC
Pin Connection V DC Pin Connection V DC
1 Left In 1.6 7 0,5-0,9
2 Left In V 1.6 8 Right out 14.2
3 Mute 15.3 9 VS 28
4 Right In V 1.6 10 Left out 13.9
5 Right In 1.6 11 0,5-0,9
6 Gnd 0 12 Left In 0.6
IC501 TDA835X
Pin Connection V DC Pin Connection V DC
1 Input A 0,98 (0) 6 Vertical Flyback Supply Voltage 45,6 (10,9)
2 Input B 0.94 (0) 7 Output A 7,64 (0,1)
3 Supply voltage 14,7 (1.0) 8 Guard Output 0,3 (0)
4 Output B 7,55 (0,4) 9 Feedback Input 7,9 (0)
5 Gnd 0 (0)
IC601 MC44608 AP
Pin Connection V DC Pin Connection V DC
1 Demag 0.85 (0.0) 5 Driver 2.1 (0.14)
2 I sense 0.1 (0.32) 6 VCC 12.3 (8.8)
3 Control input 5 (5.5) 7 Not connected -
4 Gnd 0 8 VI 116 (117)
(*) Standby values are given in parenthesis
IC701 TDA6107
Pin Connection V DC Pin Connection V DC
1 Red in 2.3-2.5 6 Vdd supply 190
2 Green in 2.5-2.7 7 Red out 134-137
3 Blue in 2.5-2.7 8 Green out 128-130
4 Gnd 0 9 Blue out 130-137
5 Black 4.5-5.5
PIN VOLTAGES OF SOME TRANSISTORS
1. PH601 (PC127FY) PHOTOCOUPLER 2. T603 (BC848) NPN
Pin Standby VDC ON VDC Standby VDC TV ON VDC
1 12.5 11 B C E B C E
2 11.5 10 T603 0.6 0.02 0 0.1 0.3 0
3 5.5 5
4 8.8 12.3
3. T604 (BC848) NPN 4. T605 (BC848) NPN
Standby VDC TV ON VDC Standby VDC TV ON VDC
B C E B C E B C E B C E
T604 0.02 12.7 0 0.7 0.05 0 T605 0.6 0.02 0 0.1 0.7 0
5. T606 (BC848) NPN 6. T607 (BC848) NPN
Standby VDC TV ON VDC Standby VDC TV ON VDC
B C E B C E B C E B C E
T606 0.6 0 0 1 6.8 0 T607 0.6 0 0 0.1 2.5 0
7. T307 (BC848) NPN
Standby VDC TV ON VDC
B C E B C E
T307 0.6 0 0 0.1 15 0
OSCILLOSGRAPHS OF SOME IC PINS
Note: TV is connected to a patern generator (Colour bar, sound 1 kHz).
1. IC101 (TDA956X)
Pin 30 Pin 31
2V/div, 20 usn/div, Vpp=4.9 V, 15625 kHz 2V/div, 20 usn/div, Vpp=5.6 V, 15625 kHz
Pin 38 Pin 40
2V/div, 20 usn/div, Vpp=2.9 V, 15625 kHz 500 mV/div, 20 usn/div, Vpp=1.2 V, 15625 kHz
Pin 47 Pin 55
500 mV/div, 20 usn/div, Vpp=2.1 V, 15625 kHz 500 mV/div, 20 usn/div, Vpp=1.65 V, 15625 kHz
Pin 56 Pin 57
500 mV/div, 20 usn/div, Vpp=2.7 V, 15625 kHz 500 mV/div, 20 usn/div, Vpp=2.6 V, 15625 kHz
Pin 58 Pin 71
500 mV/div, 20 usn/div, Vpp=2.4 V, 15625 kHz 2 V/div, 1 msn/div, Vpp=5.2 V
Pin 72
2 V/div, 1 msn/div, Vpp=5.2 V
2. IC301 (MSP34XX)
Pin 28 Pin 29
500 mV/div, 1 msn/div, Vpp=1.8 V 500 mV/div, 1 msn/div, Vpp=1.8 V
3. IC501 (TDA835X)
Pin 1 Pin 2
500 mV/div, 10 msn/div, Vpp=1.4 V, 50Hz 500 mV/div, 10 msn/div, Vpp=1.4 V, 50Hz
Pin 7
500 mV/div, 10 msn/div, Vpp=44.6 V, 50Hz
4. T501 (2SK2381)
Gate (EW drive) Drain (EW drive)
200 mV/div, 50 usn/div, Vpp=268 mV, 15625 Hz 2 V/div, 10 usn/div, Vpp=10.7 V, 50 Hz
1. ELECTRICAL ADJUSTMENTS
1.1. Supply Voltage Adjustment
Connect a digital voltmeter to the cathode of diode D611 at the AV1 mode of the TV and set the
screen voltage to the minimum with the screen potentiometer. Adjust the main supply voltage (B+)
with P601 potentiometer to the following value (after adjustment, readjust Screen voltage).
25" : 145 VDC
28" : 145 VDC (147 VDC for A66EAK071X11)
28" Pure Flat 16/9 : 140 VDC
28" Super Flat 16/9 : 140 VDC
29" Pure Flat : 125 VDC
29" Super Flat : 125 VDC
32" Pure Flat 16/9 : 140 VDC
32" Super Flat 16/9 : 131 VDC
33" : 158 VDC
2. SERVICE ADJUSTMENTS
You need the special service remote control to enter and exit the service menu of the TV (you can
order it from the manufacturer). All buttons of the Service RC are same with the user remote control,
only service menu In / Ot was added to it (please see the picture below).
Navigation
Service In/Out : Enters to / exits from the Service Menu
P+ / P- : Moves upward / downward inside the menu
V+ / V- : Changes the value or option
Green & Red : For screen adjustment (pls see the explanation below)
OK : Changes the brightness, contrast values to 00, 3F and preset values sequentially (Its
OSD is shown). When P+ / P- buttons pressed the service menu is re shown.
2.1. AGC Adjustment
Apply a signal with amplitude 65