5
64291043SAALL-5E
Section 64291043SAALL-5, Issue 5
If three or more rate LEDs are illuminated during
Total Reach DDS train-up, then the circuit is
considered to be within Total Reach DDS deployment
guidelines. See
Figure 7
for a translation of the
signal meter loss ranges in dB. If the loop loss
indicates a marginal loop for Total Reach DDS
deployment, then a more precise loop loss
measurement can be made with the appropriate test
equipment.
Table 4. Latching Loopback Sequences
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4. TESTING
Loopback Testing
Loopback tests can be performed from the Central
Office (CO) to verify proper loop and Total Reach
DDS-R operation. The Total Reach DDS-R provides
a network loopback in response to a CSU latching or
non-latching loopback command. The Total Reach
DDS-R also provides an NIE latching loopback at all
rates. Repeater loopback operation functions in
accordance with TR-TSY-000476. See
Table 4
for
latching loopback sequence. The Total Reach DDS-R
supports testing of the 2-wire loop from the remote
end when the TROCU DP is performing a
bidirectional OCU loopback.
Figure 7. Signal Loss Indication
SC
64
56
19.2
9.6
4.8
2.4
0-10
10-20
20-30
30-40
40-50
50-56
>56
LED
SIGNAL LOSS
(dB)
Signal le
v
e
l
Signal level indicated during synchronization
