PairGain HIGAIN HRU-412, Руководство пользователя

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150-412-107-03, Revision 03 Appendix A - Specifications
HRU-412 List 7 November 19, 1999 21
I
NSERTION
L
OSS
The general guideline for HiGain system usage is that each loop has less than
35 dB of loss at 196 kHz, with 135
driving and terminating impedances.
Table 1 provides a guide for the loss over various cable gauges at 196 kHz
and 135
. The table applies to the HDSL cable pairs between the HiGain line
unit and the HiGain remote unit. Without specific loop insertion loss data, add
3 dB for each bridged tap and 1 dB for each cable gauge change.
The DC cable resistance determines the simplex powering resistance path of
the loops. The maximum allowable resistance for a HiGain system is 800
over two HDSL simplex loops. For example, where 12 kft AWG 24 equals
34.08 dB (insertion loss), resistance is at 622
and well below the 800
limit.
Table 4. HDSL Loss Over Cables
Cable Gauge
Loss at 196 kHz
(db/kft)
per kft
26/0.4mm 3.88 83
24/0.51mm 2.84 52
22/0.61mm 2.18 32
19/0.91mm 1.54 16