ADTRAN Total Access 1500 Total Reach DDS-DP, Руководство по установке и обслуживанию

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Testing
61180105L1-5C 11
Testing
The TR DDS ‐ DP is equipped with logic level bantam test access jacks that permit testing in
both directions using a portable test set. Latching DS0 and CSU loopback sequences and alter ‐
nating CSU loopback sequences are supported.
Alternating loopbacks do not operate when the 64 kbps data rate is selected. Choose NEAR to
test toward the customer loop; choose FAR to test toward the T ‐ carrier. In the FAR direction, a
DS0 loopback sequence will loop the unit directly across the T ‐ carrier system. In the NEAR
direction, a DS0 loopback sequence will loop the unit directly connected to the portable test
set.
NOTE
If 64 kbps is selected, the unit will only respond to latching loopback
sequences. Alternating sequences are not valid at this rate.