Nortel Networks NN43001-301 - Manual (Page 259)

Hardware description 259
essentially replaces the D-channel circuit on the NTAK79 PRI card. (The
NTAK79 PRI card does not support the NTBK51 Downloadable D-channel
handler daughterboard.)
A second difference between the NTAK79 and NTBK50 2.0 Mb PRI cards
is that the NTAK79 has an onboard clock controller while the NTBK50
supports the NTAK20 clock controller daughterboard.
Note: If the NTAK93 D-channel daughterboard is attached to the
NTBK50 PRI card instead of the NTBK51 Downloadable D-channel
daughterboard, the NTBK50 PRI card functions in the same manner
as the NTAK79 PRI card.
NTAK79 2.0 Mb PRI circuit card
The 2.0 Mb Primary Rate Interface card provides the physical interface for
the digital E-1 carrier on the system. The card includes an onboard clock
controller and onboard D-channel handler. It is installed in slots 1-9 in the
main cabinet. On IP Expansion cabinets, it is installed in slots 11-19, 21-29,
31-39, 41-49 of the first, second, third, and fourth expansion cabinets,
respectively.
For information on the NTAK79 faceplate LEDs, refer to ISDN Primary Rate
Interface Maintenance (NN43001-717).
NTBK50 2.0 Mb PRI circuit card
The 2.0 Mb Primary Rate Interface card provides the physical interface for
the digital E-1 carrier on the system. The card is installed in slots 1-9 in the
main cabinet or Media Gateway. On IP Expansion cabinets, it is installed
in slots 11-19, 21-29, 31-39, 41-49 of the first, second, third, and fourth
expansion cabinets, respectively.
ATTENTION
IMPORTANT!
Each Media Gateway that has a digital trunk must have a clock controller set to
an external reference clock.
Note: Clocking slips can occur between Media Gateway systems that
are clocked from different COs, if the COs are not synchronized. The
slips can degrade voice quality.
The NTBK50 supports the following clock controller and D-channel handler
daughterboards:
• NTAK20 clock controller daughterboard
• NTAK93 D-channel handler daughterboard, or NTBK51 Downloadable
D-channel daughterboard.
Nortel Communication Server 1000
ISDN Primary Rate Interface Installation and Commissioning
NN43001-301 02.03 Standard
Release 5.5 7 December 2007
Copyright © 2003-2007, Nortel Networks
.