Cisco GS7000 Installation And Operation Manual page 50

Chapter 2 Theory of Operation
1x4 Redundant Forward Configuration Modules Description
The 1x4 Redundant Forward Configuration Module is used when the 1.2 GHz
GS7000 Node is configured with two optical receivers routed to all four outputs of
the amplifiers in a redundant configuration. Receiver 1 is the primary receiver and
Receiver 2 is the backup. The active receiver is selected with a digital signal from the
status monitor/local control module.
The following diagram shows how this module functions.
1x4 Redundant Forward Configuration Modules with Forward RF
Injection Description
The 1x4 Redundant Forward Configuration Modules with forward RF injection are
similar to the 1x4 Redundant Forward Configuration Modules, but are used with the
Forward Local Injection (FLI) Module. The FLI Module routes an RF signal from an
external source to the Forward Configuration Module which is then coupled with
other inputs from an optical receiver.
The following diagram shows how this module functions.
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