150-231-165-01, Revision 01
Overview
HLU-231 List 6E
September 22, 1998
1
O
VERVIEW
The PairGain
®
HiGain
®
HLU-231 List 6E is the Central Office (CO) side of a repeaterless, T1 transmission
system. When used in conjunction with a remote unit or HRU, the system provides 1.544 Mbps transmission on
two unconditioned copper pairs over the full Carrier Service Area (CSA) range. This line unit can be used in
applications with or without HDUs.
The CSA includes loops up to 12,000 feet of 24 AWG or 9,000 feet of 26 AWG wire, including bridged taps. The
HiGain system uses HDSL transmission technology as recommended by Bellcore TA-TSY-001210. The HiGain
system complies with GR-63 CORE, TR-TSY-000499 and GR1089 CORE.
F
EATURES
•
Selectable DSX-1 Pre-equalizer
•
Front Panel HDSL S/N Margin Display
•
Selectable Loopback activation codes
•
RS-232 maintenance port
•
Front-panel user option setup
•
Front Panel DS1 splitting & bridging access
•
Lightning and power cross protection on HDSL interfaces
•
784 kbps full-duplex 2B1Q HDSL Transmission on two pairs
•
Front panel status indicating LED
•
Automatic front-panel display blanking
•
Margin threshold alarm
•
HAIS & SAIS options
•
Easy default setting of user options
•
New T1 transceiver chip
•
Circuit ID option
A
PPLICATIONS
HiGain systems provide a cost-effective, easy-to-deploy method for delivering T1 High Capacity Digital Service
(HCDS) over metallic pairs.
•
The service is deployed over two unconditioned, non-loaded copper pairs, yet it demonstrates a quality that
is competitive with fiber optics.
•
Conventional, in-line, T1 repeaters are not required.
•
Cable pair conditioning, pair separation and bridged tap removal are not required.
Each loop has no more than 35 dB of loss at 196 kHz, with driving and terminating impedances of 135
Ω
.
provides a “loss” guide for the various cable gauges at 196 kHz and 135
Ω
. The table applies to the HDSL cable
pairs between the HLU, HRU, and HDU modules. In the absence of specific insertion loss measurement data, add
3 dB for each bridged tap and 1 dB for each cable gauge change.