CTC Union ETU-01A, Installation And Operation Manual

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Chapter 1. Introduction
6
November 2001
The
ETU-01A
features V.54 loop back capabilities for
performing local analog loop back and remote digital loop back as
well as progressive BERT testing. The operator at either end of the
line may test both the
ETU-01A
and the line in the remote digital
loop back mode. The loop back is controlled by local LCD
display setting, serial console, optional SNMP or by the DTE
interface for V.35, RS-232 and RS-530.
When loop back is selected from the LCD menu system, the
unit generates one of fourteen different test patterns, according to
ITU, for direct end-to-end integrity testing. The Error indicator
flashes for each bit error detected.
Multiple clock source selection provides maximum flexibility
in connecting both the E1 and user data interface. The E1 link may
be clocked from the recovered receive clock, from the user data
port or from the internal oscillator.
1.3 System Timing Considerations
The ETU-01A has the flexibility to meet the timing
requirements of various system configurations. The timing mode for
the E1 link and the user channel is selected through the LCD menu
system, a serial console or via optional SNMP management.