How to Remove Colour Patch in the TV set
Color Patch on TV Screen
Color Patch
Repair Guide
COLOR PATCH ON CRT SCREEN
 COLOR PATCH LOCATION ON CRT SCREEN
SAMTEL
COLOR PATCH ON CRT SCREEN
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COLOR PATCH ON CRT SCREEN
WHY COLOR PATCH ?
1. MISLANDIND AT CORNERS ( ONE COLOR ENTER INTO ANOTHER COLOR )
 NO PROPER CORRECTION OF LANDING AT CORNERS IN CRT
 DIRECTIONAL EFFECTS
2. MISLANDIND & CHANGE IN LANDING AT CORNERS
( ONE COLOR ENTER INTO ANOTHER COLOR )
 DUE TO EXTERNAL UNDESIRED MAGNETISM
RECEIVER INTERIORS





LEAKAGE FLUX OF FBT, POWE TRANSFORMER ETC.
LEAKAGE FLUX OF RESTRICTED CURRENT OF ADG COIL
LEAKAGE FLUX OF SPEAKERS
BY MAGNETIZING OF CHASSIS AND OTHER SHEET METAL
INTERNAL DEGAUSING AMP TURN ( AT )
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COLOR PATCH ON CRT SCREEN
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RECEIVER EXTERIORS




EFFECT BY GROUND MAGNETISM AND STEEL STRUCTURE
LEAKAGE FLUX FROM HIGH VOLTAGE TRANSMISSION CABLE( AC FREQUENCY )
EXTERNAL SPEAKERS
OTHER FACTORS
3. MISLANDIND & ONE SIDE SHIFTED LANDING AT
AT LEFT AND RIGHT POINT
 DUE TO POOR YAMMING AND UNBALANCED LANDING AT LEFT
AND RIGHT POSITION IN CRT
 MAJOR CHANGE IN GROUND MAGNETISM ( VERTICAL )
4. MISLANDIND DUE TO DOMING EFFECT AT LEFT
AND RIGHT POSITION OF CRT
 POOR LANDING / YAMMING AT DOMING POINTS ( L / R )
 BRIGHT PICTURE ( MORE LUMINANCE ) FOR A LONG TIME
COLOR PATCH ON CRT SCREEN
SAMTEL
COLOR PATCH REPAIR
1. MISLANDIND AT CORNERS
( ONE COLOR ENTER INTO ANOTHER COLOR )
2. MISLANDIND & CHANGE IN LANDING AT CORNERS
( ONE COLOR ENTER INTO ANOTHER COLOR )




EXTERNALLY DEGAUSS THE CRT FACE / SET
CONFIRM THE PATCH & LOCATION
ATTACH RUBBER MAGNET TO FUNNEL AT PATCH CORER
COVER RUBBER MAGNET COMPLETELY WITH ACETATE TAPE
( IF POSSIBLE )
COLOR PATCH ON CRT SCREEN
SAMTEL
COLOR PATCH REPAIR
COLOR PATCH ON CRT SCREEN
COLOR PATCH REPAIR
RECEIVER INTERIORS





LEAKAGE FLUX OF FBT, POWE TRANSFORMER ETC.
LEAKAGE FLUX OF RESTRICTED CURRENT OF ADG COIL
LEAKAGE FLUX OF SPEAKERS
BY MAGNETIZING OF CHASSIS AND OTHER SHEET METAL
INTERNAL DEGAUSING ( AT ), PTC, RESISTANCE, SHAPE ETC
V IMP
RECEIVER EXTERIORS
 EFFECT BY GROUND MAGNETISM AND STEEL STRUCTURE
 LEAKAGE FLUX FROM HIGH VOLTAGE TRANSMISSION CABLE
( AC FREQUENCY )
 EXTERNAL SPEAKERS
 OTHER FACTORS
SAMTEL
COLOR PATCH ON CRT SCREEN
SAMTEL
COLOR PATCH REPAIR
3. MISLANDIND & ONE SIDE SHIFTED LANDING AT
AT LEFT AND RIGHT POINT
 SLIDING ( OPENING AND CLOSING ) OF 2 POLE TO ENSURE
 BALANCED LANDING / NO PATCH AT LEFT AND RIGHT
COLOR PATCH ON CRT SCREEN
COLOR PATCH REPAIR
 SLIDING ( OPENING AND CLOSING ) OF 2 POLE TO ENSURE
 BALANCED LANDING / NO PATCH AT LEFT AND RIGHT
SAMTEL
COLOR PATCH ON CRT SCREEN
COLOR PATCH REPAIR
4. MISLANDIND DUE TO DOMING EFFECT AT LEFT
AND RIGHT POSITION OF CRT
 POOR LANDING / YAMMING AT DOMING POINTS ( L / R )
 o BRIGHT PICTURE ( MORE LUMINANCE ) FOR A LONG TIME
 USE 2 POLE BY
SLIDING TO COMPROMISE
BEST LANDING AT L / R AND
AT DOMING POINTS
 IF REQUIRED MOVE DY BACK
AND ENSURE BEST LANDING AT
L / R AND AT DOMING POINTS
SAMTEL
How to Remove Colour Patch in the TV set
Color Patch on TV Screen
Steps : 1). Check the set condition after using external degaussing coil as per below process:
2). If Patch removed properly, then check the internal degaussing of set as per below process
& if not then do as per the process in next slide:
a). Create the patch in the ON set either by degaussing coil or by rotating the set as below:
b). Switch OFF the set in patch condition for 10 mins from mains supply
c). Switch ON the set & check whether patch removed or not.
d). If patch removed that means Internal degaussing in set is OK.
e). But if patch is still available that means internal degaussing (either D.Coil, PTC or relay circuit) is faulty
& main reason of Patch in the set
3). Open the set & check the PTC & D.Coil Resistance by multimeter as below:
PTC Resistance : 9, 14 or 18 ohm in OK condition as per specs otherwise faulty
Degaussing Coil Resistance : 13 ohm in OK condition as per specs otherwise faulty
4). In case of any of above faulty, replace the same otherwise check relay circuit
Check Switching Transistor in the path of 12V to relay & relay signal from MICON
5). Replace the faulty part either switching transistor or relay to correct the internal degaussing in set
Color Patch on TV Screen
How to Remove Colour Patch in the TV set
Color Patch
Steps :
1). If problem remains in the set, even after using external
degaussing coil as shown in picture
2). apply purity magnets to back side of CPT on DY
(Note: Magnets to apply with back side of same where
patch occurs) as below:
Purity Magnet
Magnet Part Code :
1100003636
3). Patch will get removed in the set, do external degaussing
again to verify the patch in the set
Set condition after using
magnet in the set
Purity
Magnet
Magnet Part
Code :
1100003636
Convergence Poles Info
4 Pole:-It is used
to adjust Vertical
& horizontal RED
& BLEU Lines
individually
- Identification
on Pole is “4”
2 Pole:-It is used
to adjust purity
for purity lending
(Not required in
field)
-Identification on
Pole is “P”
6 Pole:-It is used to adjust
Vertical & horizontal RED &
BLEU Lines at a same time
-Identification on Pole is “6”
6 Pole