Poor C/N Performance - Cisco GS7000 Troubleshooting Manual

Poor C/N Performance

Note
1
2
Note • Assumes 2.5% OMI/CH or 20% composite.
• Assumes 1310 nm wavelength / Add one dB for 1550.
• Assumes 0dB attenuator switch setting unless noted, if otherwise subtract attenuator value from reading.
• Assumes -4dB optical input, if otherwise add or subtract 2dB RF for each 1dB optical input.
Poor C/N Performance
Follow this troubleshooting flowchart. Also see the notes following the chart.
Troubleshooting
4
Description
For standard receiver
If the green LED is Off, it is outside optical
input range. Green (On) indicates that light is
present and the optical input value is higher than
-10 dBm.
The recommended RF output level at the output
of the receiver module is 27 dBmV (+7.0 dBmV
as measured at the -20 dB RF test point). This
setup is recommended to achieve the best
possible performance.
For low input receiver
If the green LED is Off, it is outside optical
input range. Green (On) indicates that light is
present and the optical input value is higher than
-14 dBm.
The recommended RF output level at the output
of the receiver module is 27 dBmV (+7.0 dBmV
as measured at the -20 dB RF test point). This
setup is recommended to achieve the best
possible performance with 8 dB setting.
Troubleshooting