Nortel Networks Circuit Card 311 - Manual (Page 587)

Operation 587
Figure 147
Loop start call states - incoming call from CO/FX/WATS
The alerting signal into the Meridian 1 is 20 Hz (nominal) ringing sent by
the CO. When an incoming call is answered, ringing is tripped when the
Meridian 1 places a low-resistance dc loop across the tip and ring leads
toward the CO. See
Figure 153 "Loop start call states - incoming call from
CO/FX/WATS" (page 594) and Figure 154 "Loop start call connection
sequence - incoming call from CO/FX/WATS" (page 595) .
The alerting signal into the CS 1000 is 20 Hz (nominal) ringing sent by
the CO. When an incoming call is answered, ringing is tripped when the
CS 1000 places a low-resistance dc loop across the tip and ring leads
toward the CO. See
Figure 149 "Loop start call states - incoming call" (page
589) and Figure 150 "Loop start call connection sequence - incoming call"
(page 590) .
Nortel Communication Server 1000
Circuit Card Reference
NN43001-311 01.04 Standard
Release 5.0 23 May 2008
Copyright © 2003-2008, Nortel Networks
.