ADTRAN 1200218L1, User Manual

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Chapter 6. Diagnostics
61200663L1-1 OSU 300 User Manual 6-5
Figure 6-5. Payload Loopback Test
Payload BERT
This selection performs a bit error rate test on the selected port.
This test is non-intrusive to the other three ports. Only one BERT
test may be performed at a time. This test is normally performed
from the remote and local ends simultaneously to determine
whether the errors are coming from the transmit or the receive
direction (see Figure 6-6).
Figure 6-6. Payload BERT Test
DTE Loopback
This test is used to verify proper operation of the link between the
OSU 300 and the terminal equipment. During this test, all data sent
by the terminal equipment is looped back to the terminal
DTE
MUX
OSU 300
BERT OUT
BERT IN
DTE
MUX
OSU 300