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Table 390 impedance matching switch selection, Table 391 impedance matching switch selection, Table 392 impedance matching switch selection – Nortel Networks Circuit Card 311 User Manual

Page 939

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Architecture

939

Table 390
Impedance matching switch selection

Cable

On

Off

75 ohms

S2

S1

120 ohms

S1

S2

Note: The ON position for all the switches is towards the bottom of the
card. This is indicated by a white dot printed on the board next to the
bottom left corner of each individual switch.

The line interface provides for the use of either 75ohm coaxial or 120ohm
twisted pair cable. The impedance is selected by a switch, as shown in the
settings table below.

Table 391
Impedance matching switch selection

Cable

On

Off

75 Ohm

S2

S1

120 Ohm

S1

S2

Note: The ON position for all the switches is towards the bottom of the
card. This is indicated by a white dot printed on the board adjacent to
the bottom left corner of each individual switch.

The line interface provides for the use of either 75 ohms coaxial or 120
ohms twisted pair cable. The impedance is selected by a switch, as shown
in

Table 392 "Impedance matching switch selection" (page 939)

.

Table 392
Impedance matching switch selection

Cable

On

Off

75 ohms

S2

S1

120 ohms

S1

S2

Note: The ON position for all the switches is towards the bottom of the
card. This is indicated by a white dot printed on the board next to the
bottom left corner of each individual switch.

Carrier grounding

The NTAK79 card provides the capability of selectively grounding the shield
of the Tx and/or Rx pairs of the carrier. Closing (down) the on-board switch
applies FGND to the appropriate carrier cable shield. The switch settings are
shown in

Table 393 "Carrier shield grounding switch settings" (page 940)

.

Nortel Communication Server 1000

Circuit Card Reference

NN43001-311

01.04

Standard

Release 5.0

23 May 2008

Copyright © 2003-2008, Nortel Networks

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