Cisco Cisco 862 MHz GainStar Amplifier Guide De Montage
Troubleshooting
42
Low or Degraded Forward RF Signal
The forward RF signal can be measured at the GainStar Line Extender module
forward input and forward output main test point.
forward input and forward output main test point.
Low or Degraded Forward RF Signal Troubleshooting Table
Before you begin troubleshooting for a low or degraded forward RF signal, verify
that the GainStar Line Extender is receiving the proper forward RF input signal from
the upstream amplifier.
that the GainStar Line Extender is receiving the proper forward RF input signal from
the upstream amplifier.
Important: You cannot balance the GainStar Line Extender without the proper forward RF
input signal.
Make sure you have configured the GainStar Line Extender module according to the
specifications in the design print, and the GainStar Line Extender has warmed up for
approximately one hour.
input signal.
Make sure you have configured the GainStar Line Extender module according to the
specifications in the design print, and the GainStar Line Extender has warmed up for
approximately one hour.
Make sure you are using the proper tilt reference when setting levels. An 1 GHz
design balanced at 550 MHz requires a corrected tilt reference to compensate for the
difference in carrier levels between 550 MHz and 1 GHz. The tilt reference at 550
MHz is lower than the tilt reference at 1 GHz. Refer to the tilt charts in Technical
Information for more information.
design balanced at 550 MHz requires a corrected tilt reference to compensate for the
difference in carrier levels between 550 MHz and 1 GHz. The tilt reference at 550
MHz is lower than the tilt reference at 1 GHz. Refer to the tilt charts in Technical
Information for more information.
Possible Cause
Solution
The forward RF signal is weak or
degraded at the forward input test point.
degraded at the forward input test point.
Verify that the line extender is receiving
the proper forward RF input signal from
the upstream amplifier.
Important: You cannot balance the line
extender without the proper forward RF
input signal.
the proper forward RF input signal from
the upstream amplifier.
Important: You cannot balance the line
extender without the proper forward RF
input signal.
The forward RF signal is normal at the
forward input test point, but it is weak or
degraded at the forward output test
point.
forward input test point, but it is weak or
degraded at the forward output test
point.
Verify that all the proper accessories,
pads, EQs, and signal directors (if
applicable) are firmly installed in the
correct locations.
Verify that the factory installed
accessories are firmly installed in the
correct locations.
Replace the RF mainboard.
pads, EQs, and signal directors (if
applicable) are firmly installed in the
correct locations.
Verify that the factory installed
accessories are firmly installed in the
correct locations.
Replace the RF mainboard.