Cisco Prisma II, Инструкция по установке и эксплуатации

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Chapter 1 Module Introduction
4 78-4015908-01 Rev F
The dual reverse receiver contains two separate optoelectronic receivers. Optical
input is through two optical connectors mounted on the front of the module. The RF
output is through two connectors on the rear of the module.
In the reverse receiver, each optical input signal is separately detected by a
photodiode and converted to an electrical signal before being sent to an RF amplifier.
Each amplified RF signal then goes to its respective output connector on the rear of
the module.
Each RF output can be attenuated by as much as 26.25 dB, relative to no attenuation,
in 0.75 dB increments. The actual RF output levels of the dual reverse receiver,
attenuated by 20 dB, can be monitored at two -20 dB test points on the front panel.
An optical AGC feature can be used to regulate each RF output level. With this
feature disabled, each receiver RF output level will change by 2 dB for every 1 dB
change in its optical input level. When enabled, optical AGC automatically adjusts
RF output attenuation to maintain the RF output level at a set value (within limits)
despite changes in optical input level.
When the receiver module is placed in Single operating mode, both receiver
channels in the module will continue to operate even if the optical input level falls
below the major alarm threshold.
When the receiver module is placed in Independent operating mode, each receiver
channel in the module can be independently configured for Master or Slave
redundant operation. This eliminates the need for additional interface hardware to
configure redundancy relationships, and if multiple chassis are used, requires only
that the chassis be connected to the same ICIM domain.
RF output attenuation, optical AGC, redundancy, and other operating parameters of
the reverse receiver can be controlled by an ICIM2 or ICIM2-XD, LCI software,
TNCS or ROSA software, CLI commands, or the ICIM Web Interface.
Receiver Optical Input
The optical inputs are standard SC/APC connectors.
Laser Warning
WARNING:
Avoid damage to your eyes! Do not look into any optical connector while the
system is active. Even if the unit is off, there may still be hazardous optical
levels present.