Atsc/ Qam Front- End Troubleshooting Flow - LG LST-3100A Service Manual

5. ATSC/ QAM Front- End Troubleshooting Flow

START
YES
Is Power supplied normally?
YES
Is RF signal detected?
(using Spectrum Analyzer)
YES
Check IC203's output signals of
DATA( Fig. 01 ) (AR200,AR201),
packet valid signal( Fig. 02 )(AR202
or the pin 27 of IC203) and Byte
clock(the pin 30 of CN2301)
( Fig. 03 )
YES
Check Error flag LED. (LD200)
OFF: normal, ON: Error
YES
END
FIG. 01
Check the power lines referring
the circuit diagram
Change channel with DTV signal
Check the status of connection on PCB.
Check the NIM Tuner(IC203) and
peripheral parts
FIG. 02
3-31
FIG. 03