Nortel Circuit Card 311 Reference page 597

Figure 156
Loop start call connection sequence - outgoing call to CO/FX/WATS
Ground start operation
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.
Copyright © 2003-2008, Nortel Networks
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Nortel Communication Server 1000
Circuit Card Reference
NN43001-311 01.04 Standard
Release 5.0 23 May 2008
Operation 597