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TROUBLE SHOOTING GUIDE

1 . NO POWER Circuits Checked:
Power input
Protection Circuit
NO POWER Secondary B+ line short
DPM Circuit



TROUBLE IN
CHECK NO POWER CORD or
AC SOCKET? AC SOCKET SOLDER




CHECK NO TROUBLE IN FUSE
FUSE OK? F901, 3.15A/250V




CHECK NO TROUBLE IN
C904 (DCV)? D901 or R903


DCV = 140~370V



CHECK NO TROUBLE IN
IC901 OK? IC901(STR5717)




CHECK NO TROUBLE IN
Q921, Q922, Q921, Q922, R999
R999




CHECK TROUBLE IN
SMPS TRANSFORMER NO SMPS SECONDARY
SECONDARY B+ LINE SHORT
CIRCUIT




TROUBLE IN
PRIMARY OTHER
COMPONENTS

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2. NO CHARACTER


Circuits Checked:
Video Circuit and its related
circuits.
NO CHARACTER




CHECK TROUBLE IN
NO
IC301 PIN 2, 4, 6 R/G/B SIGNAL,
SIGNAL LEVEL SIGNAL CABLE




CHECK
NO TROUBLE IN
IC201 PIN 16, 28
IC301 OR PIN 9, 10
SIGNAL LEVEL
CLAMP PULSE




CHECK NO TROUBLE IN
Q301 ~ Q309 Q301 ~ Q309




CHECK TROUBLE IN
NO
CATHODE VIDEO PERIPHERAL CIRCUIT
LEVEL OF CPT PCB




TROUBLE IN
VIDEO OUTPUT CLAMP
CIRCUIT (Q310)




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3. NO RASTER
Circuits Checked:
High voltage generating
NO RASTER circuit.




CHECK NO TROUBLE IN
SIGNAL CABLE SIGNAL CABLE




CHECK TROUBLE IN
NO
IC701 PIN 1 VOLTAGE 12V LINE, IC202, IC701,
ABOUT 12V Q910




CHECK
IC701 PIN 3
HOR. SQUARE PULSE NO TROUBLE IN
(FREQUENCY ABOUT IC701
31.5KHz/35KHz/
38KHz/48KHz)




CHECK
FBT PIN 2 B+ NO TROUBLE IN
31.5KHz=93V Q901 Q905
48KHz=150V




CHECK TROUBLE IN
Q706 COLLECTOR Q706, C719, C718, D708, D709,
NO
FLYBACK PULSE FBT, DEFLECTION YOKE,
VOLTAGE ABOUT FBT B+ LINE
1100Vp-p AT 31KHz Q905, Q911, Q914, IC202




CHECK
CDT HEATER NO TROUBLE IN
VOLTAGE ABOUT 6.3V LINE
6.3V




TROUBLE IN
G2 VOLTAGE

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4. TROUBLE IN H.V SYNC
Circuits Checked:
H.V-sync input circuit
Mode Control Circuit(IC201)
TROUBLE IN H.V-Deflection IC(IC601,701)
HOR. OR VER. SYNC Sync input circuit.




CHECK
NO TROUBLE IN
CONNECTOR
P201 PIN 2, 4 SIGNAL CABLE
SIGNAL




CHECK NO TROUBLE IN
IC701 PIN 9, 10
IC202, Q401, Q402
SYNC?




TROUBLE IN
IC701 OR OTHER
COMPONENTS




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5. TROUBLE IN DPM



SUSPEND/STAND-BY/OFF MODE
LED NO AMBER




CHECK
IC202 PIN 16 NO TROUBLE IN
ABOUT IC202
0V




CHECK
IC202 PIN 17 ABOUT NO TROUBLE IN
5V AT OFF IC202
MODE ONLY




CHECK NO TROUBLE IN
12V, 6.3V LINE IC202, Q910, Q919




TROUBLE IN
LD901




CHECK INPUT WATTAGE
OFF MODE < 8W
SUSPEND < 15W
STAND BY < 15W




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