Sony KV-21FA210 (serv.man2) Service Manual ▷ View online
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KV-21FA210
Self-Diagnostic Screen Display
For errors with symptoms such as “power sometimes shuts off” or “screen sometimes goes out” that cannot be confirmed, it is possible to bring up past
occurrences of failure on the screen for confirmation.
To Bring Up Screen Test
In standby mode, press buttons on the Remote Commander sequentially, in rapid succession, as shown below:
Display
Channel 5
Sound Volume -
Power ON
Self-Diagnostic Screen Display
Numeral “0” means that no fault was detected.
Numeral “1” means a fault was detected one time only.
SELF DIAGNOSTIC
2: 000
3: N/A
4: 000
5: 001
101: N/A
3: N/A
4: 000
5: 001
101: N/A
Handling of Self-Diagnostic Screen Display
Since the diagnostic results displayed on the screen are not automatically cleared, always check the self-diagnostic screen during repairs. When you
have completed the repairs, clear the result display to “0”.
Unless the result display is cleared to “0”, the self-diagnostic function will not be able to detect subsequent faults after completion of the repairs.
Clearing the Result Display
To clear the result display to “0”, press buttons on the Remote Commander sequentially when the diagnostic screen is displayed, as shown below:
Channel 8
ENTER
Quitting the Self-Diagnostic Screen
To quit the entire self-diagnostic screen, turn off the power switch on the Remote Commander or the main unit.
Self-Diagnostic Circuit
+B overcurrent (OCP)
Occurs when an overcurrent on the +B (135V) line is detected by pin 72 of IC001 (A Board). If the voltage of pin 72 of IC001 (A Board) is less than 1V
when V.SYNC is more than seven verticals in a period, the unit will automatically turn off.
I-Prot
Occurs when an absence of the vertical deflection pulse is detected by pin 78 of IC001 (A Board). Power supply will shut down when waveform interval
exceeds 2 seconds.
IK (AKB)
If the RGB levels* do not balance within 2 seconds after the power is turned on, this error will be detected by IC001 (A Board). TV will stay on, but
there will be no picture.
*(Refers to the RGB levels of the AKB detection Ref pulse that detects 1K).
Note that this differs from entering the Service Mode (Sound Volume + ).
A BOARD
IC001
Y/CHROMA JUNGLE
A BOARD
IC545
V. OUT
A BOARD
IC001
SYSTEM
A BOARD
IC002
MEMORY
IK-AKBIN
FROM
CV BOARD
IC1751 PIN 5
I-HLDWN
FROM
A BOARD
IC561
PIN 7
72
O-LED
REF
I-Prot
IO-BDAT
BDA
DISPLAY
51
3
78
79
53
5
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KV-21FA210
1-1. REAR COVER REMOVAL
SECTION 1: DISASSEMBLY
1-2. CHASSIS ASSEMBLY REMOVAL
1-3. SERVICE POSITION
Chassis Assembly
Claw
6
Screws +BVTP 4X16 TYPE2 TT(B)
Rear Cover
A Board
KB Board
CV Board
1
Unplug KB Board and 2 pin woofer connector and move out of
the way.
2
Press on catch tab to release A Board.
3
Disconnect remaining cables to allow A Board to be removed.
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KV-21FA210
1. Discharge the anode of the CRT and remove the anode cap.
2. Unplug all interconnecting leads from the defl ection yoke, neck
assembly, degaussing coils and CRT grounding strap.
3. Remove the CV Board from the CRT.
4. Remove the chassis assembly.
5. Loosen the neck assembly fi xing screw and remove.
6. Loosen the defl ection yoke fi xing screw and remove.
7. Place the set with the CRT face down on a cushion and remove
the degaussing coil holders.
8. Remove the degaussing coils.
9. Remove the CRT grounding strap and spring tension devices.
10. Unscrew the four CRT fi xing screws [located on each CRT
corner] and remove the CRT [Take care not to handle the CRT
by the neck].
by the neck].
1-4. PICTURE TUBE REMOVAL
WARNING: BEFORE REMOVING THE ANODE CAP
High voltage remains in the CRT even after the power is disconnected. To avoid electric shock,
discharge CRT before attempting to remove the anode cap. Short between anode and CRT
coated earth ground strap.
High voltage remains in the CRT even after the power is disconnected. To avoid electric shock,
discharge CRT before attempting to remove the anode cap. Short between anode and CRT
coated earth ground strap.
Coated
Earth
Ground
Strap
ANODE CAP REMOVAL PROCEDURE
WARNING: High voltage remains in the CRT even after the power is disconnected. To avoid electric shock, discharge CRT before attempting to
remove the anode cap. Short between anode and coated earth ground strap of CRT.
NOTE: After removing the anode cap, short circuit the anode of the picture tube and the anode cap to either the metal chassis, CRT shield, or carbon
painted on the CRT.
remove the anode cap. Short between anode and coated earth ground strap of CRT.
NOTE: After removing the anode cap, short circuit the anode of the picture tube and the anode cap to either the metal chassis, CRT shield, or carbon
painted on the CRT.
REMOVAL PROCEDURES
HOW TO HANDLE AN ANODE CAP
1. Do not use sharp objects which may cause damage to the surface of the anode
cap.
2. To avoid damaging the anode cap, do not squeeze the rubber covering too
hard. A material fi tting called a shatter-hook terminal is built into the rubber.
3. Do not force turn the foot of the rubber cover. This may cause the shatter-hook
terminal to protrude and damage the rubber.
10
6
5
4
3
1
2
Turn up one side of the rubber cap in
the direction indicated by arrow a .
the direction indicated by arrow a .
Use your thumb to pull the rubber
cap fi rmly in the direction indicated
by arrow b .
cap fi rmly in the direction indicated
by arrow b .
When one side of the rubber cap separates from
the anode button, the anode cap can be removed
by turning the rubber cap and pulling it in the
direction of arrow c .
the anode button, the anode cap can be removed
by turning the rubber cap and pulling it in the
direction of arrow c .
8
7
9
a
b
Anode Button
c
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KV-21FA210
The following adjustments should be made when a complete
realignment is required or a new picture tube is installed.
These adjustments should be performed with rated power supply
voltage unless otherwise noted.
Set the controls as follows unless otherwise noted:
VIDEO MODE: Standard
PICTURE CONTROL: Normal
BRIGHTNESS CONTROL: Normal
SECTION 2: SET-UP ADJUSTMENTS
Perform the adjustments in order as follows:
1.
Beam Landing
2.
Convergence
3.
Focus
4.
Screen (G2)
5.
White Balance
Note Test Equipment Required:
1.
Color Bar Pattern Generator
2.
Degausser
3.
DC Power Supply
4.
Digital Multimeter
2-1. BEAM LANDING
Before beginning adjustment procedure:
1. Degauss the entire screen.
2. Feed in the white pattern signal.
1. Degauss the entire screen.
2. Feed in the white pattern signal.
ADJUSTMENT PROCEDURE
1. Input a raster signal with the pattern generator.
2. Loosen the deflection yoke mounting screw, and set the purity
2. Loosen the deflection yoke mounting screw, and set the purity
control to the center as shown below:
Purity Control
3. Turn the raster signal of the pattern generator to green.
4. Move the deflection yoke backward, and adjust with the purity control
4. Move the deflection yoke backward, and adjust with the purity control
so that green is in the center and red and blue are even on both
sides.
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5. Move the deflection yoke forward, and adjust so that the entire
screen becomes green.
6. Switch over the raster signal to red and blue and confirm the
condition.
7. When the position of the deflection yoke is determined, tighten it with
the deflection yoke mounting screw.
8. If landing at the corner is not right, adjust by using the disk magnets.
a
c
b
d
b
a
c
d
Purity control
corrects this area.
Disk magnets
or rotatable disk
magnets correct
these areas (a-d).
Deflection yoke positioning
corrects these areas.
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