User's Manual

Installation Guide
23 of 27
Power level is too high Power level is too low Signal is not present
Install one or more 10 dB
(AX3155-ECF-10) or 20
dB (Ax3155-ECF-20) low
pass attenuators between
the power inserter and the
cable modem.
If more than 30 dB of
attenuation is required,
reduce the hub’s
downstream power setting.
Verify the CPE alignment.
Verify the hub’s
downstream power setting.
Reduce/remove the low pass
attenuation.
Reduce the cable and RF
hardware loss between CPE
and cable modem or add bi-
directional amplification.
Verify that the range and
Fresnel Zone clearance are
within specifications.
Verity that the CPE Adaptor
and DC inserter are
installed properly
Verify the DC power level
at the input to CPE is
between 15 and 24 VDC.
Verify the coaxial cable
connections.
Verify that the range and
Fresnel Zone clearance are
within specifications.
Verify cable modem output signal at CPE
Using a spectrum analyzer or digital signal level meter, verify that the channel power into
the CPE is between +5 and +20dBmV for optimal performance and at a minimum
between 0 and +25 dBmV. If it is too high or too low, adjust the Upstream Attenuation
setting on the Arcwave MIB screen a proportionate amount.