Cisco GS7000, Инструкция по установке и эксплуатации

Страница: 121 / 254

Reverse Path Setup Procedure
101
Reverse Path Setup Procedure
Introduction
This procedure describes how to perform the reverse path setup. Perform this
procedure only if your 1.2 GHz GS7000 Node has an active reverse path.
Optical Transmitter Setup Procedure
Perform the following steps to set up the proper level into the reverse path optical
transmitters.
1 Open the housing according to Opening and Closing the Housing (on page 122).
2 Verify the level of the input reverse RF signals at the RF test points located near
the main ports of the RF amp module. Nominal level is +17 dBmV per channel.
Install the appropriate value input pad at the REV PORT IN PAD location to
attenuate the signal to the desired level for the reverse path of the node.
3 With the input to the node port set to 17 dBmV per channel, a 4 dB transmitter
input attenuator pad should be installed on the optical interface board (just
above the transmitter module) to achieve 13 dBmV level into the optical
transmitter (-7 dBmV at the transmitter -20 dB test point). This RF input level
into the high gain reverse transmitter will achieve an optical modulation index
(OMI) of 10%.
4 Repeat steps 2 and 3 for each RF port carrying a reverse path signal.
5 Use an optical power meter to measure the transmitter optical output power.
(1330 nm or 1550 nm)