Section 150-319-251
Revision 01
Page 2
A. PRODUCT OVERVIEW
1. DESCRIPTION AND FEATURES
1.01
PairGain's HiGain Line Units Model ELU-
319, Lists 5 and 6 (Figure 1), are the Public
Exchange side of a repeaterless G.703 transmission
system. When used with an ERU-412 HiGain
Remote Unit (ERU), the system provides 2.048
Mbps transmission on two unconditioned copper
pairs. The HiGain system uses HDSL (High-bit-rate
Digital Subscriber Line) transmission technology as
recommended by Bellcore TA-TSY-001210. HiGain
complies with TR-TSY-000063 (Network Equipment
Building System (NEBS) Generic Equipment
requirements) and TR-TSY-000499 (Transport
System Generic Requirements–TSGR) common
requirements.
1.02
Revision History of this practice.
Revision 01—July 6, 1995
a) Initial release.
b) This initial release is supported by
software version 1.3.
1.03
The ELU-319 is compatible with the
PairGain 22-slot HMS-318 shelf and the
associated G.703 HiGain connector panel HCP-322.
1.04
ELU-319 Product Family:
•
List 5: 75-ohm G.703 Impedance
•
List 6: 120-ohm G.703 Impedance
1.05
ELU-319 Issue 1 features:
•
-130V dc line power for
ERU-412 or EDU-451
•
Four-digit front panel display for HDSL
signal/noise (S/N) margin configuration and
alarms
•
RS-232 maintenance port
•
Non-volatile configuration memory
•
Front panel splitting and bridging access to
G.703 interface
•
Lightning and power cross protection on
HDSL interfaces
•
1040 kbps full-duplex two-bits one-
quaternary (2B1Q) HDSL transmission on
each of two pairs
•
Front panel status-indicating light-emitting
diode (LED) indicator
•
On / Off front-panel display power cycling
•
G.703 Loss of Signal (LOS) detector (125
consecutive zeros)
•
Margin threshold alarm
•
Single step default setting
•
Circuit ID option
•
Improved tolerance to cable noise
•
Supports EDU-451 doubler
2. APPLICATIONS
2.01
The HiGain System provides a cost-
effective, easy to deploy method for
delivering G.703 High Capacity Digital Service
(HCDS) over metallic pairs. The fiber-like quality
service is deployed over two unconditioned, non-
loaded copper pairs. Conventional span repeaters
are not required. Cable pair conditioning, pair
separation and bridged tap removal, are also not
required.
2.02
The HiGain system operates with any
number of other G.703, Plain Old Telephone
System (POTS), digital or analog data service or
other HiGain Systems sharing the same cable
binder group. HiGain provides a means of quickly
deploying service in advance of fiber-optic
transmission systems. By using HiGain G.703, you
can connect service within a few days or even a few
hours. You can install fiber optic systems at a
leisurely pace and cut-over from HiGain when the
time allows. You can then easily remove the HiGain
and utilize it elsewhere.
2.03
Table 1 provides a guide for the loss of
various cable gauges at the HDSL line rate
of 260 kHz and 135 ohms. The table applies to the
HDSL cable pairs between the ELU and the EDU-
451 as well as between the EDU-451 and a second
EDU-451 or the ERU-412. Add 3 dB for each
bridged tap and 1 dB for each cable gauge change.
TABLE 1. HDSL CABLE LOSS
Cable Gauge
Loss @ 260
kHz(db/km)
Ohms per km
26/0.4mm
13.94
272
24/0.51mm
10.47
171
22/0.61mm
8.14
105
19/0.91mm
5.74
52
