Sony KV-20FS120 Service Manual ▷ View online
14
KV-20FS120/21FM120/21FS120/21FA310/24FS120/25FS120
KV-20FS120/21FM120/21FS120/21FA310/24FS120/25FS120
2-2. CONVERGENCE
Before starting convergence adjustments:
1 Perform FOCUS, VLIN and VSIZE adjustments.
2. Set BRIGHTNESS control to minimum.
3. Feed in dot pattern.
Vertical Static Convergence
1. Adjust V. STAT magnet to converge red, green and blue dots in the
center of the screen (Vertical movement adjust S V.STAT RV1750 to
converge).
converge).
B
G
R
Center dot
V.STAT magnet
RV1750
V.STAT
B
G
R
2. Tilt the V. STAT magnet and adjust static convergence to open or
close the V. STAT magnet.
When the V. STAT magnet is moved in the direction of arrow a and b,
red, green, and blue dots move as shown below:
red, green, and blue dots move as shown below:
B
R
G
B
R
G
R
G B
B
G R
1
2
b
b
b
b
b
b
b
a
a
b
a
a
a
a
3
R
G
B
B
G
R
Horizontal Static Convergence
If the blue dot does not converge with the red and green dots, peform
the following:
1. Move BMC magnet (a) to correct insuffi cient H.Static convergence.
the following:
1. Move BMC magnet (a) to correct insuffi cient H.Static convergence.
2. Rotate BMC magnet (b) to correct insuffi cient V.Static convergence.
3. After adjusting the BMC magnet, repeat Beam Landing Adjustment.
BMC MA
GNET
PURITY
V.STAT
b
BMC magnet
a
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KV-20FS120/21FM120/21FS120/21FA310/24FS120/25FS120
KV-20FS120/21FM120/21FS120/21FA310/24FS120/25FS120
Dynamic Convergence Adjustment
Before performing this adjustment, perform Horizontal and Vertical Static
Convergence Adjustment.
1. Slightly loosen defl ection yoke screw.
Convergence Adjustment.
1. Slightly loosen defl ection yoke screw.
2. Remove defl ection yoke spacers.
3. Move the defl ection yoke for best convergence as
shown below:
B
G
R
G
B
R
G
B
R
R
R
G
B
G
B
G
B
R
B
G
R
G
B
G
B
R
R
G
B
G
G
B
R B
R
R
4. Tighten the defl ection yoke screw.
5. Install the defl ection yoke spacers.
TLH Plate Adjustment
1. Input crosshatch pattern.
2. Adjust PICTURE QUALITY to standard, PICTURE and BRIGHTNESS
to 50%, and OTHER to standard.
3 Adjust the Horizontal Convergence of red and blue dots by tilting the
TLH plate on the defl ection yoke.
(TLV)
YCH
XCV
TLV
CV
Board
Board
RV1750
V.STAT
V.STAT
TLH Plate
(YHC, TLV) 20"/21" Models
(TLV, XCV, YCH, TLV) 24"/25" Models
B R R B
(R)(B) (B)(R)
(R)(B) (B)(R)
TLH+
TLH-
TLH-
4. Adjust XCV core to balance X axis.
5. Adjust YCH VR to balance Y axis.
6. Adjust vertical red and blue convergence with V.TILT (TLV VR.)
Note: Perform adjustment 3-6 while tracking items 1 and 2.
Screen-Corner Convergence
1. Affi x a permalloy assembly corresponding to the misconverged areas:
b
a
c
d
a
b
d
a-d: screen-corner
misconvergence
c
2-3. FOCUS
1. Adjust FOCUS control for best pictures.
Focus (FV)
Screen (G2)
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KV-20FS120/21FM120/21FS120/21FA310/24FS120/25FS120
KV-20FS120/21FM120/21FS120/21FA310/24FS120/25FS120
2-4. SCREEN (G2)
1. Input a dot pattern.
2. Set the PICTURE and BRIGHTNESS controls at minimum and
COLOR control at normal.
3. Adjust SBRT, GCUT, BCUT in service mode with an oscilloscope as
shown below so that voltages on the red, green, and blue cathodes
are 160 ± 2VDC.
are 160 ± 2VDC.
Pedestal
160 – 2VDC
Ground
±
4. Observe the screen and adjust SCREEN (G2) VR in FBT to obtain
the faintly visible background of dot signal.
2-5. METHOD OF SETTING THE SERVICE
ADJUSTMENT MODE
Service Mode Procedure
1. Standby mode (power off).
2. Press Display
Channel 5
Sound Volume +
Power
on the Remote Commander (press each button within a second).
Service Adjustment Mode On
1. The CRT displays the time being adjusted.
Mode
Category
Display
Item
Display
Item
Signal
Type
Type
ntsc
service
defl
vchp
00000000
00000000
hsiz
16
2. Press 1 or 4 on the Remote Commander to select the time.
3. Press 3 or 6 on the Remote Commander to change the data.
4. Press MUTING then ENTER to save into the memory.
Service Adjustment Mode Memory
Turn the set off then on to exit Service Adjustment Mode.
service defl hsiz
16
ntsc
vchp 00000000 00000000
Category
Display
Item
Mode
Item
Data
Data
Signal
Type
Type
write
ENTER
Green
Red
MUTING
2-6. WHITE BALANCE ADJUSTMENTS
1. Input an entire white signal with burst.
2. Set to Service Adjustment Mode.
3. Set the PICTURE and BRIGHTNESS to minimum.
4. Adjust with SBRT if necessary.
5. Select GCUT and BCUT with 1 and 4 .
6. Adjust with 3 and 6 for the best white balance.
7. Set the PICTURE and BRIGHTNESS to maximum.
8. Select GDRV and BDRV with 1 and 4 .
9. Adjust with 3 and 6 for the best white balance.
10. Press MUTING then ENTER to save into the memory.
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KV-20FS120/21FM120/21FS120/21FA310/24FS120/25FS120
KV-20FS120/21FM120/21FS120/21FA310/24FS120/25FS120
Hold-Down Readjustment
If the setting indicated in Step 2 of Hold-Down Operation Confi rmation
cannot be met, readjustment should be performed by altering the
resistance value of R565 component marked with X.
cannot be met, readjustment should be performed by altering the
resistance value of R565 component marked with X.
+
IABL
ABL
T585
FBT
range
-
Ammeter
3.0 mA DC
A
3-2. B+ VOLTAGE CONFIRMATION AND
ADJUSTMENT
Note: The following adjustments should always be performed when
replacing the following components, which are marked with Y on the
schematic diagram on the A Board:
replacing the following components, which are marked with Y on the
schematic diagram on the A Board:
A BOARD: Y IC600, PH602
1. Using a Variac, apply AC input voltage: 130 + 2.0 / - 0.0 VAC.
2. Input a DOT pattern at Q.C.
3. Set the PICTURE and the BRIGHTNESS controls to minimum.
4. Confi rm the voltage of A Board between TP-23 & Ground is =135.6
± 1VDC.
5. If step 4 is not satisfi ed, replace the components listed above, then
repeat steps 1 through 3.
SECTION 3: SAFETY RELATED ADJUSTMENTS
3-1. X R565 CONFIRMATION METHOD
(HV HOLD-DOWN CONFIRMATION) AND
READJUSTMENTS
READJUSTMENTS
The following adjustments should always be performed when replacing
the following components which are marked with Y on the schematic
diagram:
the following components which are marked with Y on the schematic
diagram:
DY, T585, CRT, IC001, IC561,
IC600, C506, C507, C508, T511,
L510, C588, L588, C566, C561,
C563, D567, D568, D566, PH602,
R567, R568, R565, R566, R562,
R563, R561, R528……....A Board
IC600, C506, C507, C508, T511,
L510, C588, L588, C566, C561,
C563, D567, D568, D566, PH602,
R567, R568, R565, R566, R562,
R563, R561, R528……....A Board
HV HOLD-DOWN
R565
R565
Part Replaced (Y)
Adjustment (X)
Preparation Before Confi rmation
1. Using a Variac, apply AC input voltage: 120 ± 2 VAC.
2. Turn the POWER switch ON.
3. Input a white signal and set the PICTURE and BRIGHTNESS
controls to maximum.
4. Confi rm that the voltage between C566 (+) or TP30 and ground
is more than 97 VDC for 20”/21” models, or 105 VDC for 24”/25”
models.
models.
Hold-Down Operation Confi rmation
1. Connect the current meter between Pin 11 of the FBT (T585) and the
PWB land where Pin 11 would normally attach (See Figure 1 on the
next page).
next page).
2. Input a dot signal and set PICTURE and BRIGHTNESS to minimum:
IABL = 100 ± 100µA.
3. Confi rm the voltage of A Board TP-23 is 135.6 ± 1VDC.
4. Connect the digital voltmeter and the DC power supply via Diode
1SS119 to C566 (+) and ground (See Figure 1 on next page).
5. Increase the DC power voltage gradually until the picture blanks out.
6. Turn DC power source off immediately.
7. Read the digital voltmeter indication
(standard < 117.0 VDC) for 20”/21” models
(standard < 138.0 VDC) for 24”/25” models.
(standard < 138.0 VDC) for 24”/25” models.
8. Input a white signal and set PICTURE and BRIGHTNESS to
maximum: IABL = 1350 ± 100µA for 20”/21” models or
IABL = 1650 ± 100µA for 24”/25” models
IABL = 1650 ± 100µA for 24”/25” models
9. Repeat steps 4 through 7.
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