See figure 136 on – Nortel Networks Circuit Card User Manual
Page 601
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NT8D14 Universal Trunk card
Page 601 of 906
Circuit Card
Description and Installation
Figure 136
Two-way, loop OAID, TIE trunk call states – outgoing call to far-end PBX
System (near) end
Near end
originates
Far end
disconnect
Near end
disconnect
Idle
Near end
disconnects
first
Far end
answers
553-AAA1147
Far end
disconnects
first
Ground on tip,
battery on ring
Battery on tip,
ground on ring
Low-resistance loop
High-resistance loop
Far end
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