2
61291004L2-5, Issue 2
61291004L2-5B
C A U T I O N !
SUBJECT TO ELECTROSTATIC DAMAGE
OR DECREASE IN RELIABILITY.
HANDLING PRECAUTIONS REQUIRED.
Application
In a typical application the TRDDB can be used to
provide test access at the DS0 level for DDS circuits
served from a single CO (
Figure 2
). By using
TRDDB channel units in this configuration instead of
other dataport channel units, valuable port space on
1/0 DCS devices can be saved.
TRDDB channel units can be used to deliver
multipoint DDS circuits connected to MJUs in
ADTRAN GPC shelves or D4/SLC-96 channel banks
(
Figure 3
). The TRDDB can also be used in
applications where an IXC T1 is back-hauled to a
metallic SMAS point in a local DDS serving CO
(
Figure 4
).
NOTE
The TRDDB must be used with an appropriate
TROCU-R unit.
2. INSTALLATION
After unpacking the unit inspect it for damage. If
damage is noted file a claim with the carrier, then
contact ADTRAN. See
Warranty and Customer
Service
.
• Protected Loopback prevents false latching
loopback at 64 kbps
• Alternating Mux-Out-of-Sync/Abnormal Station
trouble code during loss of loop synchronization
• Utilization in D4 channel bank and SLC-96
remote terminal applications
• NEAR and FAR logic level Bantam test access
• Loop Quality Monitor and latching loopback
Description
The ADTRAN D4 TRDDB is a 2-wire Total Reach
DDS functional replacement for the following
ADTRAN 4-wire OCU part numbers:
• 1104004L3
D4OCBRD2AA
• 1104004L4
D4OCBRE2AA
• 1105004L1
D4OCBSD2AA
• 1105004L2
D4OCBSE2AA
• 1105018L1
D4OCBTD2AA
The TRDDB delivers data at rates up to 64 kbps using
a single copper pair. Used in combination with the
TROCU-R termination unit, the TRDDB can
accommodate extended loop lengths, eliminating the
need for DDS repeaters. The TRDDB span powers the
remote TROCU-R located at the customer premises.
The TROCU-R converts the 2-wire signal to the
traditional 4-wire Alternate Mark Inversion (AMI)
signal for presentation to the customer.
The ADTRAN TRDDB occupies a single channel
position in the WECO
®
compatible D4 channel bank,
GPC shelf, or AT&T
®
SLC-96 terminal. It provides
the interface between a DS0 signal and the 2-wire
metallic loop extending to the customer premises. The
TRDDB will interoperate with another TRDDB, OCU
DDB, DS0 DP, MJU, or 1/0 DCS and can be located
in an end office, hub office, or intermediate office.
Figure 2. DS0 Level Test Access for DDS Customers with Two End Points Served from Same
CO.
DSU/
CSU
DSU/
CSU
2-wire
Loop
2-wire
Loop
Test
Head
GPC, D4,
or
SLC96
DS0
TRDDB
TRDDB
DS0
50 kft
50 kft
Customer Premises
TR
OCU-R
TR
OCU-R
CO
