Dte And Loop Test (Ll) - ADTRAN DSU 5600 User Manual

Chapter 3. Test Modes

DTE and Loop Test (LL)

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The DTE and Loop test is initiated at the local DSU 5600 and
allows independent testing of the separate sections of the DSU
5600. First, it allows the local DTE interface to be tested with data
from the terminal or test equipment. Second, it allows the loop
interface section of the local DSU 5600 to be tested from the
remote site over the actual communications circuit. Testing from
the remote end of the circuit is done with test data generated by
the remote DSU or terminal type test equipment.
The DTE and Loop test splits the DSU 5600 into separate DTE
and Loop interface sections and then loops the transmit data of
each interface back to its respective receive data. A block dia-
gram illustrating the loopback points and the signal paths for
this test is shown in Figure 3-3.
To initiate the DTE and Loop test, perform the following steps:
1. Press Select three times to turn On both the DTE and Loop
test indicators.
2. Press Test while these test indicators are On. The DTE and
Loop LEDs Flash during initialization of the test and turn On
solid once the test is in progress.
To terminate this test, press Test.
DSU 5600 User Manual 61200.078L1-1