Cisco GainMaker Optoelectronic Node 1GHz with 65 86 MHz Split インストールガイド
Chapter 3 Balancing and Setup
Proceed to To Complete Reverse Path Balancing (on page 80).
To Complete Reverse Path Balancing
Complete the following steps to finish the amplifier setup.
1 Monitor the tilt of the signals being received at the headend or hub reverse
1 Monitor the tilt of the signals being received at the headend or hub reverse
optical receiver RF output test point.
Note:
Note:
The tilt is the difference in signal level between the highest and lowest
frequencies in the reverse passband, or between the highest and lowest
frequency CW test signals.
Most systems prefer to have minimal reverse tilt (flat levels) at the headend.
To minimize tilt, change the value of the amplifier reverse output equalizer.
2 Monitor the amplitude (level) of the signals being received at the headend or hub
reverse optical receiver RF output testpoint.
a Compare the received level to the reference level desired.
b If using a sweep system that is x dB below standard CW carrier levels, be
a Compare the received level to the reference level desired.
b If using a sweep system that is x dB below standard CW carrier levels, be
sure to consider that the receive level should also be x dB below the CW
reference level.
c To adjust the receive level to make it match the desired reference level, alter
the value of the amplifier reverse output pad. Each 1 dB increase in pad value
should result in a corresponding 1 dB decrease in receive level, and each 1 dB
decrease in pad value should give a 1 dB increase in receive level.
3 Once the proper receive level and tilt of the test signals have been achieved,
properly close the amplifier housing and repeat the process at the next reverse
amplifier in the downstream cascade.
Important:
Reinstall design print value reverse input pads for any port whose input pad
may have been temporarily replaced with a 0 dB value pad for reverse path
balancing purposes.
Work outward from the node, and outward from each external split in the
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