Cisco Cisco Explorer Set-top Software Version 2.1 User Guide
Subscribers Are Seeing a Black Screen on a Digital Channel
749244 Rev G
199
Access the following
diagnostic screen.
diagnostic screen.
Evaluate the
following field.
following field.
What value do I want to see?
CURRENT QAM
S/N
QAM-64—28 dBmV to 34 dBmV
desired range
desired range
(minimum 25 dBmV)
QAM-256—32 dBmV to 34 dBmV
desired range (minimum 39 dBmV)
desired range (minimum 39 dBmV)
Note: If the S/N value is not within
the desired range, check the QAM
and the RF signal levels.
the desired range, check the QAM
and the RF signal levels.
CURRENT QAM
Corr Bytes
Uncor Blks
Corr Bytes and Uncor Blks
should be static—if the values
are incrementing rapidly, the QAM
could be sending bad blocks of
data. Check the RF signal levels
coming out of the QAM and the
DHCT connection.
should be static—if the values
are incrementing rapidly, the QAM
could be sending bad blocks of
data. Check the RF signal levels
coming out of the QAM and the
DHCT connection.
CURRENT FDC
Freq
FDC frequency—should match
the frequency on the QPSK
the frequency on the QPSK
Note: If the FDC frequency does
not match that of the QPSK, check
the RF signal levels and the signal
quality for noise.
not match that of the QPSK, check
the RF signal levels and the signal
quality for noise.