Specifications

Installation and Operation Manual Chapter 6 Troubleshooting and Diagnostics
FCD-E1LC Ver. 1.0 Testing the Unit 6-17
The test and loopback functions are described in the following sections. The test
functions are identified by the command used to activate the corresponding
test/loopback function. For clarity, the figures used to illustrate the signal paths
while a loopback or test is activated show only two user ports: one data channel
and the (optional) sublink.
Main Link Tests and Loopbacks
Main Link Local Analog Loopback (LP LOC ANA ML)
This loopback is performed by connecting the main link transmit signal to the
input of the receive path within the LIU section of the main link interface, as
shown in
Figure 6-1.
Local FCD-E1LC
Processor
"1"
Main
Link
Data
Channel
User's
Equipment
Sub
Link
User's
Equipment
Figure 6-1. Main Link Local Analog Loopback
The test signal is provided by the equipment connected to the local user ports:
each one must receive its own transmission.
Before activating this loopback on an FCD-E1LC with Ethernet interface,
disconnect the LAN cable from the rear panel Ethernet interface.
During the loopback, the local FCD-E1LC sends an unframed “all-ones” signal to
the remote FCD-E1LC.
This test fully checks the local FCD-E1LC operation and the connections to the
local user’s equipment.
Main Link Remote Analog Loopback (LP REM ANA ML)
The main link remote analog loopback is a locally performed analog loopback
towards the remote equipment. The loopback connects, at the local FCD-E1LC,
the regenerated receive signal to the transmit input of the main link interface
within the LIU section of the main link interface, as shown in
Figure 6-2.
The test signal is provided by the user's equipment connected to the ports of the
remote FCD-E1LC: each one must receive its own transmission.
This test checks the connections to the remote user’s equipment, all the circuits
of the remote FCD-E1LC, the main link interface functions of the remote and local
FCD-E1LC, and the transmission plant connecting the two FCD-E1LC.
Note