Nortel Networks Circuit Card - Manual (Page 826)

Page 826 of 906 NTRB21 DTI/PRI/DCH TMDI card
553-3001-211 Standard 3.00 August 2005
To provide CEMUX communication with the card, changes are also required
to create an I/O entry for the card.
You can install this card in slots 1 through 4 in the MG 1000S. The card is not
supported in the MG 1000S Expansion. Up to four digital trunks are
supported in each MG 1000S.
Note 1: For CISPR B group cabinets, the active Clock Controller
(NTAK20) can only occupy slots 1-3. For FCC and/or CISPR A group
cabinets, this limitation does not exist - the Clock Controller can occupy
any available slot 1-9.
Note 2: On non-ECM system cabinets, the NTAK20 may be placed in
slots 1-9. On cabinets NTAK11Dx and NTAK11Fx, the active NTAK20
must be placed in slots 1-3 (slots 4-10 may not be used).
Physical description
The NTRB21 card uses a standard 9.5" by 12.5" multi-layer printed circuit
board with buried power and ground layers.The clock controller
daughterboard is fastened by standoffs and connectors.
The NTRB21 card has seven faceplate LEDs. The first five LEDs are
associated with the NTRB21 card. The remaining two LEDs are associated
with the clock controller and DCHI daughterboards. See Figure 176.
IMPORTANT!
Each MG 1000S that has a digital trunk must have a clock controller
clocked to an external reference clock.