Functional Description
700-712-100-01, Revision 01
14
May 10, 1999
UTU-712 and ETU-762 List 1
On-Board Power Supply Modules
•
The UTU-712 line unit has an on-board DC-to-DC power supply module.
•
The ETU-762 desktop unit has an on-board AC-to-DC power supply module.
•
A shelf-mounted UTU-712 receives power from a local source of -36 Vdc to -72 Vdc or from the EAC-830
In-Shelf Power Supply.
•
An enclosure mounted UTU-712 receives power from a local source of -36 Vdc to -72 Vdc or from the
enclosure’s built-in AC-to-DC power supply (when provided).
•
The ETU-762 receives power from its on-board AC-to-DC power supply.
S
INGLE
-P
AIR
R
ATE
S
ELECTABLE
A
PPLICATIONS
Applications for single-pair rate selectable HDSL are those that require transport of voice and data at various rates
over various distances on a e of wire. Depending on line noise and the HDSL rate selected, spans of up to 8.5 km
(5.3 miles)
can be deployed without the use of doublers. The HDSL line rate depends on the number of time slots
selected. The UTU-712 and ETU-762 each have 12 time slots with a bandwidth of from 64 kbps to 768 kbps
(1 to 12 time slots selected). Each time slot represents a 64 kbps increment of the available bandwidth.
shows a single-pair video-conferencing application using a 384 kbps HDSL payload rate (6 time slots
selected). Customer data is input at the remote serial port and transported over the HDSL loop at 384 kbps to the
exchange office, a distance of up to 4.7 km from the customer site.
Figure 8.
Single-Pair Rate Selectable HDSL Video Conferencing Application
Single-pair rate selectable HDSL units can also be used with Frame Relay networks.
shows such an
application where the remote unit is connected to a Frame Relay Access Device (FRAD) and the local unit is
connected to a Frame Relay switch. The HDSL rate is set at 256 kbps (4 timeslots) for a reach of up to 5.1 km.
Figure 9.
Single-Pair Rate Selectable HDSL Frame Relay Application
The single-pair rate selectable HDSL units (local and remote) must be locally powered.
