User Manual

Installation Guide
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Problem Solution
the following checks:
• Verify that the “Select Downstream
Power” setting is correct for the
downstream modulation and
wireless range.
• Change “Downstream Air
Frequency” to a different channel
to rule out interference.
• Verify that the range and Fresnel
Zone clearance are within
specifications.
Does not detect and lock on to the US
channel
Using the customer cable modem’s
diagnostic interface, verify that the cable
modem is sending on the correct upstream
RF channel:
If it is sending on the correct RF channel
but can’t lock on, reduce the Upstream
Attenuation setting at the Hub.
If it does not send on the correct channel,
and Cable Interface Control and Automatic
Frequency Set are enabled, verify that the
Hub ECM and the subscriber cable modem
are assigned to the same upstream
frequency and that both are excluded from
an upstream load balancing group.
If it does not send on the correct channel,
go to the Hub and verify the following:
Using the -U/S Tap port on the Hub, verify
the Hub is receiving a wireless signal from
the CPE.
• If there is a signal present, adjust
the “Upstream Attenuation” setting
at Hub until the cable modem locks
on the US channel.
• If there is not a si
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