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TROUBLESHOOTING
NO RASTER
CHECK +B
at D807 cathode
Normal Abnormal
Check Open
Is the voltage at pin37
FUSE of AC line
& 12 of IC501 8V?
No
OK Check /replace
Yes Check the in/out Fuse,DB801,IC801
of IC841
Check pin40 Check the voltage
No of C806
of IC501(H-out) 0V
No
Check &replace
Yes 254~380V Check /replace
IC501
Check u-COM DB801,R811
Check Q741 pin15 low?
Check the voltage
No collector waveform of pin4
Check &replace No
Yes
IC501
Check /replace
Check T401 Q802 Check /replace
& each pin voltage
D806,IC803,R809
No
Check &replace Yes
IC501
Is the voltage at pin37
& 12 of IC501 8V?
NO TELETEXT
Check the
voltage of IC701 pin19
OK 0V
Check Check 5V Supply
CVBS signal Line of IC701
at IC701 pin9 & P701
OK
OK Check
IC701& IICBus Line
Not OK
Check / Replace
Q701, X701, & IC501
- 1 -
NO RASTER / SOUND OK
Check the
Heater voltage of CPT
(6 - 6.5Vrms)
OK Not OK
Check Check Check the
HV, Screen voltage of Ik Current of Heater pulse of FBT
CPT IC501, pin18 T701
Not OK OK Not OK OK Not OK
Check/Replace Check
Check
CPT Board FR704, FR901
FBT T701
Components P302, & P902
Check
Check
IC501, ZD904
FBT T701
P501, & P902
NO SOUND / PICTURE OK
Select correct
system in MENU
Check the waveform
of Q651 collector
Check / replace
Q651
Check the voltage Check the waveform
of IC101(logic) of pin3 of IC202
Check / replace
Q653,654 Check demodulated
signal of pin15
Check demodulated
of input pin of IC601 or 602
Check the Vcc
of IC601/602
- 2 -
NO PICTURE / NO SONUD
Is any OSD displayed?
No
Yes
OK Check IC01 pin30,31,32 Check receiving system in MENU
(R,G,B) & excute Auto-program.
Not OK
Check IC01 pin9,10 Does the Auto-program Yes
(V-Sync, H-Sync) operate properly.
Check IC01 pin36,37
(XLC, EXLC) Not OK
& IC01
Store in manual-program MENU
Check Not OK Check 5V, 33V & IIC Bus Line
5V, 33V & of TUNER
IIC Bus Line
OK
Go to
Not OK Is the CVBS signal OK.
Check / Replace NO SOUND /
( IC501 pin6 )
TUNER, IC501 PICTURE OK
OK
Check Not OK
Check R,G,B signal
CVBS singal Line at IC501 pin19,20,21
& IC501
OK
Check / Replace
CPT Board component
- 3 -