Cisco Model GS7000 4-Port Node 1 GHz with 42 54 Split Guia Da Instalação
Poor Distortion Performance
OL-29643-02
161
Notes
These notes apply to the previous troubleshooting flowchart.
Note Description
1
Recommended RF input levels are:
Headend transmitter module: 14 dBmV
Note: Based on 79-channel loading. The input will increase as the
channel loading decreases.
channel loading decreases.
2
For standard receiver
For low input receiver
The range for optical light input
level is -10 to +3 dBm which
converts to 0.1 to 2.0 V DC. The
optimum operating range is -3
dBm to +3 dBm which converts to
0.5 to 2.0 V DC. Levels higher than
+3 dBm can cause the photo diode
to generate distortions, which add
to the distortion performance of
the link, effectively degrading the
distortion performance.
level is -10 to +3 dBm which
converts to 0.1 to 2.0 V DC. The
optimum operating range is -3
dBm to +3 dBm which converts to
0.5 to 2.0 V DC. Levels higher than
+3 dBm can cause the photo diode
to generate distortions, which add
to the distortion performance of
the link, effectively degrading the
distortion performance.
The range for optical light input
level is -10 to -1 dBm which
converts to 0.1 to 0.8 V DC. The
optimum operating range is -6
dBm to -1 dBm which converts to
0.25 to 0.8 V DC. Levels higher
than -1 dBm can cause the photo
diode to generate distortions,
which add to the distortion
performance of the link, effectively
degrading the distortion
performance.
level is -10 to -1 dBm which
converts to 0.1 to 0.8 V DC. The
optimum operating range is -6
dBm to -1 dBm which converts to
0.25 to 0.8 V DC. Levels higher
than -1 dBm can cause the photo
diode to generate distortions,
which add to the distortion
performance of the link, effectively
degrading the distortion
performance.
3
Attenuate the light to simulate the amount of light that should be at the
GS7000 Node and rerun the distortion performance. If the distortion
performance improves, there is too much light. An inline optical
attenuator or a coupler with a higher loss can reduce the light, or the
laser may have to be replaced with a lower launch power.
GS7000 Node and rerun the distortion performance. If the distortion
performance improves, there is too much light. An inline optical
attenuator or a coupler with a higher loss can reduce the light, or the
laser may have to be replaced with a lower launch power.