Nortel Networks 1000 - Manual (Page 541)

Operation 541
Figure 162
Two-way, loop DR, TIE trunk call connection sequence - incoming call from far-end PBX
In an incoming call configuration, the far-end initiates a call by placing
a low-resistance loop across the tip and ring leads. See
Figure 171
"Two-way, loop DR, tie trunk call states - incoming call from far-end PBX"
(page 551)
and Figure 172 "Two-way, loop DR, tie trunk call connection
sequence - incoming call from far-end PBX" (page 552) on. This causes
a current to flow through the battery feed resistors in the trunk circuit.
Address signaling is then applied by the far-end in the form of DTMF tones
Nortel Communication Server 1000
Circuit Card Reference
NN43001-311 02.06 Standard
27 August 2008
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