CTC Union ETU01-Plus, User Manual

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Chapter 4. Test & Diagnostics
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Chapter 4. Test & Diagnostics
4.1 General
This chapter contains procedures for performing system diagnostic tests.
4.2 Loop Back Tests
The loop back test buttons (Loc dig loopbk, Loc ana loopbk and Rem loopbk) and
the LED indicators built into the ETU01-Plus allow for rapid checking of the data
terminal, ETU01-Plus and the E1 line. Before testing the operation of the data system
equipment and their line circuits, ensure that all units are turned on and are
configured correctly. Note: DIP SW6-8 must be set ON to enable the front panel
push-button switches.
4.3 Bit Error Rate Tester
When depressing the Pattern push-button switch, the Bit Error Rate Tester (BERT)
can be activated in any diagnostics test in which the test pattern transmitted is
received by another ETU01-Plus (see Figure 4.1). When used opposite another
ETU01-Plus, either with the Pattern push-button switch depressed or with an external
BERT transmitting the same pattern (V.52 511-bit), the complete link can be tested. If
errors are encountered, the Error indicator LED will blink (for intermittent errors) or
remain on continuously (for continuous errors).
In this example, both units at the ends of the E1 link have their pattern generators
enabled.
Figure 4.1 BERT operation
ETU-01 ETU-01
Pattern
Tester
Tester
Pattern
Pattern
Generator
Generator
Pattern
Pattern
Depressed
Pattern
Depressed
External
BERT
511
RCV
XMT
E1
Link
ETU01-Plus
ETU01-Plus