CTC Union ETU-01A User Manual

Chapter 5. Loop Back and BERT Testing
96
November 2001
E1 line remote analog loop back
E1 line remote analog loop back is performed by sending a loop
back code to the remote unit. The remote unit then connects its E1
link receive signal to the output of the transmit path, before the
Channel Service Unit (CSU). This loop back test checks the
performance of the local ETU-01A, the remote ETU-01A and
the connections between them, as shown in Figured 5-4.
Figure 5-4. E1 link remote analog loop back
note:
The remote loop back codes, also referred to as data link messages, for the
ETU-01A utilize the 4 spare Sa bits within the framing timeslot (TS0).
Therefore, any remote loop back functions, including remote analog loop
back (LLB) and remote payload loop back (PLB) are only available when
running in framed mode (PCM30 or PCM31). Unframed mode does not
support any remote loop back functions.
DTE
DSU
E1
CSU
LOCAL ETU-01A
DTE
DSU
CSU
REMOTE ETU-01A

CTC Union ETU-01A Specifications

General

Brand	CTC Union
Model	ETU-01A
Category	Control Unit
Language	English