150-451-104-02, Revision 02
Functional Description
HDU-451 List 4
September 18, 1998
3
Figure 1.
HiGain Installation with Two Doublers.
F
UNCTIONAL
D
ESCRIPTION
HiGain utilizes PairGain’s Two-Binary, One-Quaternary (2B1Q) HDSL
transceiver systems to establish two full-duplex 784 kbps data channels (total
of 1.568 Mbps) between the HLU and a remotely mounted HRU. Each
HDU-451 increases the total span of the CSA by approximately 12,000 feet
(24 AWG) or 9,000 feet (26 AWG).
A block diagram of the HDU-451 is shown in
. The
HDU-451 power supply uses the 100 to 200 Vdc power feed voltage received
on the simplex pairs to p5V and -5 Vdc required by the HDU-451
circuitry. The power feed is passed to the HDSL output, via the Output Span
Voltage Control relay, to power one other HiGain module, either a second
HDU or the remote HRU.
The maximum power dissipation of the HDU-451 is 6 watts.
O
UTSIDE
E
NCLOSURE
D
EPLOYMENT
R
ULES
Take care when deploying the HDU-451 in sealed multislot outside
enclosures, such as the PairGain 3-slot HRE-423 or 4-slot HRE-454
enclosures. To avoid excessive heat build up, follow the deployment rules
shown in
NID
SMJK
HRU-412
LIST 7*
HDSL
Doubler
2
HDU-451
HDSL
Doubler
1
HDU-451
HDSL
SPAN 1
SPAN 2
SPAN 3
Central
Office
HLU-231
(List 6D/3D)
HLU-319
(List 2/3)
DSX
9,000' 26 AWG
12,000' 24 AWG
9,000' 26 AWG
12,000' 24 AWG
-22.5 dB Max.
9,000' 26 AWG or 12,000' 24 AWG (without Doubler)
9,000' 26 AWG
12,000' 24 AWG
*Two Doubler application requires the locally powered HRU-412, List 7.
Any HRU-412 can be used for single Doubler applications.