Cisco Cisco 1 GHz GainStar Node Installationsanleitung
Low or Degraded Forward RF Signal
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Low or Degraded Forward RF Signal
The forward RF signal can be measured at the –20 dB RF test point on the mainboard
forward output test points.
forward output test points.
Low or Degraded Forward RF Signal Troubleshooting Table
Before you begin troubleshooting for a low or degraded forward RF signal, verify
that the GainStar Mini Node is receiving the proper forward optical input signal
from the forward transmitter.
Important: You cannot balance the GainStar Mini Node without the proper forward
optical input signal.
Make sure you have configured the mainboard according to the specifications in the
design print and that the node has warmed up for approximately one hour.
Make sure you are using the proper tilt reference when setting the levels. An 862
MHz or 1 GHz design balanced at 550 MHz requires a corrected tilt reference to
compensate for the difference in carrier levels between 550 MHz and 862 MHz or
1 GHz. The tilt reference at 550 MHz is lower than the tilt reference at 862 MHz or 1
GHz. Refer to Technical Information for more information.
that the GainStar Mini Node is receiving the proper forward optical input signal
from the forward transmitter.
Important: You cannot balance the GainStar Mini Node without the proper forward
optical input signal.
Make sure you have configured the mainboard according to the specifications in the
design print and that the node has warmed up for approximately one hour.
Make sure you are using the proper tilt reference when setting the levels. An 862
MHz or 1 GHz design balanced at 550 MHz requires a corrected tilt reference to
compensate for the difference in carrier levels between 550 MHz and 862 MHz or
1 GHz. The tilt reference at 550 MHz is lower than the tilt reference at 862 MHz or 1
GHz. Refer to Technical Information for more information.
Possible Cause
Solution
The forward RF signal is normal at the
forward input test point, but it is weak or
degraded at one or both of the forward
output test point.
forward input test point, but it is weak or
degraded at one or both of the forward
output test point.
Verify that all the proper accessories,
pads, EQs, and signal directors are
firmly installed in the correct locations.
Verify that the factory installed
accessories are firmly installed in the
correct locations.
Note: Verifying the factory installations
involves removing the mainboard
cover. Reinstall the mainboard cover
properly.
Replace the mainboard.
pads, EQs, and signal directors are
firmly installed in the correct locations.
Verify that the factory installed
accessories are firmly installed in the
correct locations.
Note: Verifying the factory installations
involves removing the mainboard
cover. Reinstall the mainboard cover
properly.
Replace the mainboard.