Page 494 of 544 NTBK50 2.0 Mb PRI card
553-3011-100 Standard 14.00 January 2002
Overview
The NTBK50 card provides a 2Mb PRI interface and is installed in the main
and IP expansion cabinets. The NTBK50 supports the NTAK20 clock
controller daughterboard and either the NTAK93 D-Channel interface or the
NTBK51 Downloadable D-Channel handler. The NTAK93 DCHI
daughterboard provides identical performance to the on-board NTAK79
DCHI. The NTBK51 DDCH daughterboard provides support for protocols
based on the MSDL platform.
Functional description
NTBK50 provides the following features and functions:
• recovery of the 2.048 kbps data by the CEPT receiver, at signal levels
which have been attenuated by up to 10 dB
• control of CEPT line density using HDB3 which provides 64 kbps clear
channel
• performance monitoring of the receive carrier by means of Bipolar
Violations (BPV), Slips, CRC-4 (CRC), and Frame Bit Errors (FBER)
• monitoring of receive carrier alarms including AIS, LOS, and RAI
• transmission of remote alarm when instructed
• slip-buffering receive messages
• support of National and International bits in time slot 0
• clock controller daughterboard
• D-channel interface daughterboard
• Downloadable D-channel handler daughterboard
• 32 software-selectable Tx and Rx Pad values
• conversion of PCM commanding Laws (A-A, u-u, A-u, u-A)
• Card-LAN for maintenance communications
Physical description
The NTBK50 uses a standard IPE-sized (9.5" by 12.5"), multilayer printed
circuit board. The faceplate is 7/8" wide and contains seven LEDs.