Cisco Cisco 1 GHz GainStar Node 安装指南
Low RF Output
OL-31947-02
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Low RF Output
Use the steps in the following table to troubleshoot low RF output of the GainStar
Mini Node.
Mini Node.
Low RF Output Troubleshooting Table
Possible Cause
Solution
Low RF input at the transmitter.
Verify that the RF input to the transmitter
is correct.
Check the amplifiers preceding the
transmitter for proper inputs and
outputs.
is correct.
Check the amplifiers preceding the
transmitter for proper inputs and
outputs.
Defective or improperly spliced
optical coupler (between the headend
transmitter and the node).
optical coupler (between the headend
transmitter and the node).
Replace or re-splice the coupler.
Make sure all the unused fiber pigtails
are terminated.
Make sure all the unused fiber pigtails
are terminated.
Unterminated leg of the optical
coupler.
coupler.
Make sure all the unused fiber pigtails
are terminated.
are terminated.
Low optical input to the node. The
typical optical input level should be
-4 to +2 dBm. Refer to the system
design print for the proper level.
typical optical input level should be
-4 to +2 dBm. Refer to the system
design print for the proper level.
Clean the connectors if they are
contaminated. Refer to Cleaning Optical
Connectors.
contaminated. Refer to Cleaning Optical
Connectors.
Inspect fiber routing that might be
wrapped too tightly.
Check the transmitter for the proper
optical output.
Check the link loss.
Replace any scratched connectors.
wrapped too tightly.
Check the transmitter for the proper
optical output.
Check the link loss.
Replace any scratched connectors.
Failure in the optical receiver.
Replace the GainStar Mini Node. Use the
output test point of the optical receiver to
verify the output levels.
output test point of the optical receiver to
verify the output levels.