beautypg.com

Off = d-channel, Ds-1 carrier interface, Transmitter – Nortel Networks 1000 User Manual

Page 974

background image

974

NTRB21 DTI/PRI/DCH TMDI card

receive clock output

transmit clock output

The bit rate of the receive and transmit clocks can vary slightly from each
other. This is determined by the transmit and receive carrier clocks.

Feature selection through software configuration for the D-channel
includes:

56 kbps

64 kbps clear

64 kbps inverted (64 Kbps restricted)

DCHI can be enabled and disabled independent of the PRI card, as long
as the PRI card is inserted in its cabinet slot. The D-channel data link
cannot be established unless the PRI loop is enabled.

On the NTRB21 use switch 1, position 1 to select either the D-channel
feature or the DPNSS feature, as follows:

OFF = D-channel

The ON setting for DPNSS (U.K.) is not supported at this time.

DS-1 Carrier interface

Transmitter

The transmitter takes the binary data (dual unipolar) from the PCM
transceiver and produces bipolar pulses for transmission to the external
digital facility. The Digital Signal – Level 1 (DS-1) transmit equalizer
enables the cabling distance to be extended from the card to the Digital
Signal Cross-connect – Level 1 (DSX-1), or LD-1. Equalizers are switch
selectable through dip-switches. The settings are shown in

Table 409

"NTRB21 switch settings" (page 974)

.

Table 409
NTRB21 switch settings

Switch Setting

Distance to Digital

Cross-Connect

1

DCH F/W

2

(LEN 0)

3

(LEN 1)

4

(LEN 2)

0 - 133 feet

Off

Off

Off

On

133 - 266 feet

Off

On

On

Off

266 - 399 feet

Off

Off

On

Off

399 - 533 feet

Off

On

Off

Off

533 - 655 feet

Off

Off

Off

Off

Nortel Communication Server 1000

Circuit Card Reference

NN43001-311

02.06

Standard

27 August 2008

Copyright © 2003-2008 Nortel Networks

.