Nortel Networks Circuit Card 311 - Manual (Page 598)

598 NT8D14 Universal Trunk card
Ground start operation is configured in software and implemented through
software download messages. In the idle state, the tip conductor from the
CO is open and a high-resistance negative battery is present on the ring
lead.
Ground start operation is configured in software and implemented through
software download messages. In the idle state, the tip conductor from the
CO is open and a high-resistance negative battery is present on the ring
lead.
Ground start operation is configured in software and implemented through
software download messages. In an idle state, the tip conductor from the
CO is open and a high resistance negative battery is present on the tip
of the trunk.
Incoming calls
In an incoming call, after ground is detected on the tip, the universal trunk
card scans for a ringing detection signal before presenting the call to an
attendant and tripping the ringing. When the attendant answers, a low
resistance is placed across the tip and ring conductors, which trips CO
ringing and establishes a speech path. See
Figure 157 "Ground start call
states - incoming call from CO/FX/WATS" (page 599) and Figure 158
"Ground start call connection sequence - incoming call from CO/FX/WATS"
(page 600)
.
In an incoming call, after ground is detected on the tip, the universal trunk
card scans for a ringing detection signal before presenting the call to an
attendant and tripping the ringing. When the attendant answers, a low
resistance is placed across the tip and ring conductors, which trips CO
ringing and establishes a speech path.
See Figure 161 "Ground start call states - incoming call from CO/FX/WATS"
(page 604) and Figure 162 "Ground start call connection sequence -
incoming call from CO/FX/WATS" (page 606) .
In an incoming call, after ground is detected on the tip, the universal trunk
card scans for a ringing detection signal before presenting the call to an
attendant and tripping the ringing. When the attendant answers, a low
resistance is placed across the tip and ring conductors, which trips CO
ringing and establishes a speech path. See
Figure 159 "Ground start
call states - incoming call" (page 601) and Figure 160 "Ground start call
connection sequence - incoming call" (page 602) .
Nortel Communication Server 1000
Circuit Card Reference
NN43001-311 01.04 Standard
Release 5.0 23 May 2008
Copyright © 2003-2008, Nortel Networks
.