Viavi OneExpert CATV 630, Extended Quick Start Manual

Page: 103 / 183

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Testing Next Codeword Pointer (NCP)
 Don’t disregard OFDM performance at high end or low end. Roll off of
either could impair a CM's ability to correctly receive NCP or CWs.
THINGS TO CHECK:
Lock status:
locked
Uncorrectable CWE :
none
The NCP tells the modem which CW are present and
in which profile to find each CW (CWE analysis), it is
CRITICAL for proper data communication
NCP’s start at HIGH
frequencies and
populate
down
Codewords start at
LOW frequencies and
populate UP