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TROUBLESHOOTING GUIDE
1 . NO POWER


NO POWER




CHECK NO TROUBLE IN
P901 OK? POWER CORD




CHECK NO TROUBLE IN
FUSE F901
FUSE OK?




CHECK NO TROUBLE IN
D901 (DCV)? D901


DCV = 140 336V


TROUBLE IN
CHECK NO IC901(STR6707)
IC901 OK? R912, R913




CHECK NO TROUBLE IN
Q901, Q902 Q901, Q902, D903
OK?




CHECK CHECK TROUBLE IN
NO
SMPS TRANSFORMER SMPS SECONDARY
Q905
SECONDARY
OK? B+ LINE SHORT
CIRCUIT
NO



TROUBLE IN TROUBLE IN
PRIMARY OTHER Q904, Q905, Q909
COMPONENTS



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2. NO CHARACTER


NO CHARACTER




CHECK NO REFER
SCREEN CONTROL
NO RASTER
CLOCKWISE




CHECK TROUBLE IN
NO
IC301 PIN #4,6,9 R/G/B SIGNAL,
SIGNAL LEVEL SIGNAL CABLE




TROUBLE IN
CHECK IC301
NO
IC301 PIN #17,20,26
CLAMP (PIN 14)
SIGNAL LEVEL
IC301 12V VOLTAGE




CHECK NO TROUBLE IN
IC302 PIN #3,4,10 Q308, Q309, Q310, Q311,
SIGNAL D310, D311, D312




CHECK NO TROUBLE IN
CATHODE VIDEO PERIPHERAL CIRCUIT
LEVEL OF CRT PWB




TROUBLE IN
CONNECTOR ASS'Y
(MAIN P702 & P703-VIDEO P302)



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3. NO RASTER

NO RASTER




CHECK NO
VOLTAGE(CRT TROUBLE IN
HEATER) 6.3V 6.3V LINE




CHECK NO
REFER TROUBLE IN
IC701(#4/#14) H/V SYNC.
H/V SYNC.




CHECK NO
TROUBLE IN
IC701(#6/#15) H/V IC701
OUTPUT




TROUBLE IN
CHECK NO IC501,IC502,Q501,
T702 (PIN#2) VOLTAGE Q502,Q503, Q504,
63V (at H-Freq. Q505,Q506 or
31.5kHz.) DEFLECTION YOKE




CHECK Q713 NO
TROUBLE IN
COLLECTOR ABOUT
Q713, D706, D705
1050Vp-p




CHECK G1 NO TROUBLE IN
VOLTAGE ABOUT Q202, Q203, Q204,
-10 10V Q205, Q206, Q207
0 0.4V
CHECK
IC804 PIN#20

TROUBLE IN 2 5V REFER TROUBLE IN
G2 VOLTAGE
H/VSYNC.

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4. TROUBLE IN H.V SYNC



TROUBLE IN
HOR. OR VER. SYNC




CHECK
CONNECTOR P302 NO TROUBLE IN
(#1,2) , P703(#3,4) SIGNAL CABLE
SIGNAL




CHECK
IC804 (pin #11,12) NO TROUBLE IN
H/V SYNC. H/V SYNC LINE
SIGNAL




CHECK CHECK
NO NO TROUBLE IN
IC804 (pin #22,23) IC804 (pin #1, 17)
H/V SYNC. VOLTAGE 5V LINE
SIGNAL 5V ?




3 5V CHECK Yes
CHECK TROUBLE IN
IC804 (pin #20) IC804 (pin #4) Freq. IC804
VOLTAGE 3.58MHz


0 0.4 V NO



TROUBLE IN TROUBLE IN
IC802, IC805, Q801 X801, C808, C809




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