Directv Tp- Demux /Modem Circuit - LG LSS-3200A Service Manual

7. DIRECTV TP- Demux /Modem CIRCUIT

1. If satellite channel setup is failed and "No Signal" is displayed (First check QPSK part)
START
YES
The IC 3.3V power is supplied
normally?
YES
The IC 2.5V power is supplied
normally?
YES
The clock #1 operates normally?
YES
The clock #2 operates normally?
YES
The reset signal operates normally?
YES
The clock #3 operates normally?
YES
The CAM Board clock operates
normally?
YES
END
NO
Check IC800(E9) voltage : 2.5V
NO
Check IC800(E7) voltage : 3.3V
NO
Check IC800(W18) clock waveform
: See FIG. 01
NO
Check IC800(B10) clock waveform
: See FIG. 02
NO
Check IC800(Y19) voltage : 3.3V
NO
Check X800(3) clock waveform
: See FIG. 03
NO
Check CN800(9) clock waveform
: See FIG. 04
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