Cisco GainMaker Optoelectronic Node 1GHz with 65 86 MHz Split Installation Guide
Balancing the Reverse Path
level specified by the calculation above, but the difference between the actual
output level and the level calculated above must be known. If the generator
output is x dB higher (or lower) than the level calculated, then the reference
(desired) level received at the headend or hub should also be x dB higher (or
lower) than the original headend reference level.
The station reverse input pad values are selected during the reverse system
design and are based on the need to minimize variations in return path losses for
the various reverse inputs. Do not permanently alter the values of the reverse
input pads without consulting a system designer.
In the GainMaker node, the reverse input comes after the reverse injection point
in the reverse path. Temporarily replacing the design value reverse input pad on
the port being balanced with a 0 dB pad allows the reverse injection level and the
receive levels at the monitoring end to remain constant from amplifier to
amplifier and from port to port.
An alternative to this method is to expect a receive level that is x dB lower than
An alternative to this method is to expect a receive level that is x dB lower than
normal, where x is the value of the reverse input pad on the port being balanced,
which you noted earlier in the reverse path balancing procedure.
Insert the appropriate signal amplitude into the reverse injection point. Refer to the
following illustration.
Proceed to To Complete Reverse Path Balancing (on page 81).
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:
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