Panasonic WV-BM1790 Service Manual ▷ View online
3
(2). Horizontal Hold Adjustment
Test Point: Pin 2 of Deflection Coil
Adjust:
VR301 (H-HOLD)
Main Board
8
Disconnect the signal from the Video Signal Generator.
8
Connect the Frequency Counter to Pin 2 of the Deflection
Coil.
8
Adjust VR301 to obtain 15.400 kHz ± 50 Hz.
(3). Picture Tilt Adjustment
Test Point: Video Monitor Screen
Adjust:
Deflection Coil
8
Supply the Monoscope pattern signal to the Video Input
Connector.
8
Loosen the Deflection Coil Holding Screw as shown in Fig.
4-1.
Fig. 4-1
8
Turn the Deflection Coil until the raster becomes straight
horizontally on the monitor screen.
8
Tighten the Deflection Coil Holding Screw carefully.
(4). Horizontal Width Coarse Adjustment
Test Point: Video Monitor Screen
Adjust:
L304 (H-WIDTH)
Main Board
8
Supply the Monoscope pattern signal to the Video Input
Connector.
8
Adjust L304 so that the full Horizontal Width becomes plus
6 % ± 2 % overscanning.
(5). Vertical Height and Vertical Linearity Coarse
Adjustment
Test Point: Video Monitor Screen
Adjust:
VR202 (V-HEIGHT)
Main Board
VR204 (V-LIN)
Main Board
8
Supply the Monoscope pattern signal to the Video Input
Connector.
8
Adjust VR202 so that the full Vertical Height becomes plus
6 % ± 2 % overscanning.
8
Adjust VR204 so that the circle portion of the Monoscope
pattern becomes nearly a true circle.
8
Repeat adjusting VR202 and VR204 until satisfactory.
(6). Sub-Brightness Fine Adjustment
Test Point: Video Monitor Screen
Adjust:
VR101 (CONTRAST)
Main Board
VR102 (BRIGHT)
Main Board
VR103 (SUB BRIGHT)
CRT Board
8
Supply the Stairstep signal to the Video Input Connector.
8
Adjustment should be done after more than five minutes
warm-up.
8
Turn the CONTRAST Control and the BRIGHT Control to
their mechanical center position.
8
Turn VR103 so that the 8th step of the Stairstep signal
becomes cutoff and the 7th step becomes visibly bright as
shown in Fig. 4-2.
Fig. 4-2
8th step becomes cutoff.
7th step becomes visibly bright.
Loosen Deflection Coil Holding Screw.
Centering Magnets
Deflection Coil
4
(7). Raster Distortion Adjustment
Test Point: Video Monitor Screen
Adjust:
Deflection Magnets
8
Supply Cross-hatch signal from the Video Signal
Generator to the Video Input Connector.
8
Adjust 8 magnets as shown in Fig. 4-3 so that the raster
distortion becomes minimum.
Fig. 4-3
8
The raster distortion against 8 magnets are as shown in
Fig. 4-4.
Fig. 4-4
(8). Centering and Horizontal Width Fine
Adjustment
Test Point: Video Monitor Screen
Adjust:
Centering Magnets
L304 (H-WIDTH)
Main Board
8
Supply the Monoscope pattern signal to the Video Input
Connector.
8
Adjust the Centering Magnets (See Fig. 4-1.) until the
raster becomes to the center of the monitor screen.
8
Adjust L304 so that the full Horizontal Width becomes plus
6 % ± 1 % overscanning.
8
Repeat adjusting the Centering Magnets and L304 until
satisfactory.
(9). Vertical Height and Vertical Linearity Fine
Adjustment
Test Point: Video Monitor Screen
Adjust:
VR202 (V-HEIGHT)
Main Board
VR204 (V-LIN)
Main Board
VR205 (SUB V-HEIGHT)
Main Board
Centering Magnets
8
Supply the Monoscope pattern signal to the Video Input
Connector.
8
Adjust VR202 so that the full Vertical Height becomes plus
6 % ± 2 % overscanning.
8
Adjust VR204 so that the circle portion of the Monoscope
pattern becomes nearly a true circle.
8
Adjust the Centering Magnets so that the Monoscope
pattern comes to the center of the monitor screen.
8
Repeat adjusting VR202, VR204 and the Centering
Magnets until satisfactory.
8
Set the TV Standard Selector (CCIR/EIA) to EIA position.
8
Adjust VR205 so that the proportion of the height of the
circle to the width becomes 1.25 as shown in Fig. 4-5.
Fig. 4-5
8
Set the TV Standard Selector (CCIR/EIA) to CCIR
position.
(10). Focus Adjustment
Test Point: Video Monitor Screen
Adjust:
VR104 (FOCUS)
CRT Board
8
Supply Monoscope pattern signal from the Video Signal
Generator to the Video Input Connector.
8
Adjust VR104 for best focus in the monitor screen.
600
1100
50
550
40
35
30
25
20
15
10
5
40 35 30 25 20 15 10 5
4
4
3
8
8
10
6
6
4
3
2
4
5
6
3
525 LINE
20
10
15
5
20
10
15
5
20
10
15
5
20
10
15
5
30
5
5
10 15
8
30
5
5
10 15
8
30
5
5
10
15
8
30
5
5
10
15
8
4
4
4
5
3
3
2
3
1
1.25
Width : Height = 1 : 1.25
Adjust eight magnets.
– 5 –
VR103
(SUB
BRIGHT)
(SUB
BRIGHT)
VR104
(FOCUS)
(FOCUS)
L304
(H-WIDTH)
(H-WIDTH)
CN101
T1
POWER
TRANSFORMER
POWER
TRANSFORMER
T202
FLYBACK
TRANSFORMER
FLYBACK
TRANSFORMER
VR202
(V-HEIGHT)
VR204
(V-LIN)
VR205
(SUB V-HEIGHT)
VR301
(H-HOLD)
D10
(POWER INDICATOR)
(POWER INDICATOR)
SW1
(POWER ON/OFF)
(POWER ON/OFF)
VR201
(V-HOLD)
(V-HOLD)
V102
(BRIGHT)
(BRIGHT)
VR101
(CONTRAST)
(CONTRAST)
CN901
(VIDEO IN/OUT)
(VIDEO IN/OUT)
JK1
(AC IN)
(AC IN)
SW201
(CCIR/EIA)
(CCIR/EIA)
MAIN BOARD
CRT BOARD
(COMPONENT SIDE VIEW)
(COMPONENT SIDE VIEW)
LOCATION OF TEST POINTS AND ADJUSTING CONTROLS
1
3
2
4
5
1
2
1
2
1
2
1
2
3
1
2
5
4
1
2
3
4
5
6
7
8
16
15
14
13
12
11
10
9
TAB
V.SYNCO
17
18
SYNC SP
H.AFCI
V.SYNCI
V.CHG
V.DCHG
V.VCC
V.BST
V.FB
V.OBST
V.OUT
H.AFCO
H.OSCI
V.PWADJ
H.VCC
H.PDO
2
4
1
3
4
2
5
3
1
6
2
1
3
3
4
2
1
3
2
1 C
2
1 C
S
D
1
2
3
4
5
6
7
1
GND
9
4
3
1
8
7
6
5
2
10
1
2
1
2
1
2
L
N
E
3
4
2
1
2
1
3
4
1
2
2
SCREEN
HEATER
CATHODE
GND
NC
3
NC
4
5
6
5
6
1
2
3
4
3
4
H-DY(+)
H-DY(–)
V-DY(–)
V-DY(+)
V-DY(–)
V-DY(+)
2
1
5
5
V
H
3
3 1
4
2
1
2
1
3
2
4
5
1
2
3
4
5
2
3
4
5
6
5
4
3
2
1
8
7
4
5
6
7
8
9
5
6
7
8
9
1
2
3
2
3
2
9
13
1
4
5
6
12
8
11
10
3
3
2
1
VR102
BRIGHT
BRIGHT
VR101
CONTRAST
CONTRAST
VR301
H-HOLD
H-HOLD
VR104
FOCUS
FOCUS
VR103
SUB BRIGHT
SUB BRIGHT
VR205
SUB V-HEIGHT
SUB V-HEIGHT
SW201
EIA/CCIR
EIA/CCIR
VR204
V-LIN
V-LIN
VR202
V-HEIGHT
V-HEIGHT
VR201
V-HOLD
V-HOLD
L1
DEFLECTION
COIL
DEFLECTION
COIL
SW1
POWER ON/OFF
POWER ON/OFF
L304
H-WIDTH
H-WIDTH
T202
FLYBACK TRANSFORMER
FLYBACK TRANSFORMER
T1
POWER TRANSFORMER
POWER TRANSFORMER
CRT1
CATHODE
RAY TUBE
CATHODE
RAY TUBE
R213 563
R214 242
R215 472
C206
1/50
C207 393
D202
C205 103
C204 473
C202 333
C203 105
R204 103
C301 563
R205 333
R207 3R0
C209 1000/16
D201
R209 163
R210 203
R208 391
C211 470/10
VR202 501
VR204
501
R301 683
R302
113
R303 153
C303 1/50
VR301 103
R304
122
R305
330
C306 102
Q301
R311 101
C307 333
C308 153
Q302
C314 153
C315 153
C316 15/25
CF301 1R62
R310 683
C309 22/50
C310 100/25
R306
471 1/2W
C312
2200/16
R309 150 3W
D301
R312 473
C317 470/25
D303
D304
C319 22/160
C320
333
D302
R219 271
C214 823
D102
C113 10/50
R123 222
R122 103
R102 153
R103 333
R135 821
Q101
C102
47/25
VR101 102
C103
47/25
R104
101
R106 103
R108 121
R110
471
R109 221
Q102
R105
223
R107 431
Q103
R145 331
R144 102
Q104
R143 222
R136 104
Q106
Q107
R141 221
C107 471
R137 560
L101 680
R140
JUMPER
R126 332
R905 102
C907 47/25
R217 103
R315
820
C304 562
C302 472
C201 472
D10
R10 122
R124 103
C108 220/25
R125
220 1/2W
R308 180 3W
R139 392 2W
C208 2.2/50
R206
330
C210 100/25
L201
C218 1000/16
R203 103
C212 10/50
C126 100/25
C318 103
CB102
CB101
CB103
C115
332
C116 332
R131 105
R134
105
VR104
2R2
R129
394 1/2W
R130
274 1/2W
VR103
104
R132
684 1/2W
R133
684 1/2W
CB104
R128 102
C219 152
D305
R212 560
R121 202
R1 225 1/2W
C3 104
C5 101
D1
D2
R8 4R7
C12 100/25
C7 1/50
C4 103
C8 471
C14 2200/16
R11 101
R14
333
C9 104
R12 332
C16
470/16
C2 102
C1 102
R4
470
R7
220
D3
R9 470
C17 104
C18 104
L2 220
R16 512
R15 622
R13 163
R6
181 3W
R5
333 5W
R326 JUMPER
R114
JUMPER
R113
JUMPER
R322 472
R320 103
R321 103
Q304
Q305
R325 223
Q303
R901 750
R3 156 1/2W
R2 2R2(5W)
D4
R20 392
R21 822
Q2
C11 47/25
Q3
Q4
OPEN
Q5
R202
561
R220 182
R324
473
C321 47/25
C322 103
R22
103
R19 103
R18 OPEN
R23 150
C6 102
R17
R22 5W
C105
2.2/50
E11
E12
E14
E13
E901
E902
E100
E102
E302
E301
E202
E201
E106
E107
E109
E110
E303
E104
E103
E105
E108
R317 103
C10 120/400
C20 102
R148
102
C323 153
C324 183
R327 563
R226 123
R225 223
C220 1/50
VR205
501
R228
JUMPER
R211 183
VR201 502
R229
823
R328 472
IC201
D101
D6
SW1
D5
L6
VS1
IC2
E3
CN101
CN102
T202
F1 4A 250V
E1
E2
JK1
Q1
T201
CN103
CN301
L1
L304
L303
VR102 102
E101
SW201
CN901
T1
IC1
A
B
C
D
1
2
3
4
5
6
(13.5V)
[EIA]
[CCIR]
IN
OUT
AC IN
VIDEO
H(+)
H(-)
K
G1
G2
G4
MAIN BOARD
CRT BOARD
7.9
–
2.7
2.4
2.7
94.8
–
–0.2
–0.2
2.2
2.2
2.2
8.9
8.2
2.6
2.8
–0.3
13.5
0.3
0.3
4.1
2.8
13.4
12.3
13.6
2.3
3.0
10.3
11.8
6.4
8.2
4.4
13.0
2.6
2.4
13.8
8.6
1.9
4.2
2.4
4.2
3.6
1.8
6.9
0.3
–0.1
15.9
13.5
13.5
13.5
–
–
–
Important safety notice
Components Identified by " " mark have special characteristics for safety.
When replacing any of these components, use only manufacturer's specified parts.
Note:
The value indicated in the schematic diagram should be read as follows:
Multiplier (0 - 5)
2nd. Significant Digit (0 - 9)
1st. Significant Digit (1 - 9)
2nd. Significant Digit (0 - 9)
1st. Significant Digit (1 - 9)
0
1
3
820
82 x 10 = 82 pF
102
10 x 10 = 1000 pF = 0.001
µ
F
104
10 x 10 = 100000 pF = 0.1
µ
F
0
2
4
For Capacitor
(Except Electrolytic Capacitor and Tantalum Capacitor):
(Except Electrolytic Capacitor and Tantalum Capacitor):
0
1
010
1 x 10 =
1
µ
H
8R2
8.2 x 10 =
8.2
µ
H
101
10 x 10 =
100
µ
H
0
For Coil:
< WAVEFORM >
MAIN BOARD
MAIN BOARD
1. 10
µ
s/DIV, 0.2 V/DIV
3. 10
µ
s/DIV, 0.2 V/DIV
5. 5 ms/DIV, 5 V/DIV
6. 20
µ
s/DIV, 10 V/DIV
2. 5 ms/DIV, 0.5 V/DIV
4. 20
µ
s/DIV, 50 V/DIV
<Example>
For Resistor:
330
For Resistor:
330
33 x 10 = 33
Ω
561
56 x 10 = 560
Ω
123
12 x 10 = 12k
Ω
0R00 = 0
Ω
< INDEX >
MAIN BOARD
MAIN BOARD
IC1
C3
IC2
C2
IC201 A3/B3
Q1
C2
Q2
C2
Q3
C1
Q5
C3
Q101
C3/D3
Q102
C4
Q103
C4/D4
Q104
C4
Q106
C4
Q107
C5/D5
Q301
A4
Q302
B5
Q303
A4
Q304
A5
Q305
A5
D1
D2
D2
D2
D3
C3
D4
C2
D5
C2/D2
D6
D1/D2
D10
D3
D101
C4
D102
C4
D201
B3
D202
B3
D301
B5
D302
B5
D303
B5
D304
B6
D305
B5
– 6 –
SCHEMATIC DIAGRAM
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