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Trunk circuit features
Signaling and control
553-3011-100
Standard 14.00
NT8D15 E&M Trunk Card
The following features in addition to those previously listed are provided by
each circuit:
•
Two-wire E & M type I signaling (Non-ESN)
— Near-end seizure and outpulsing with M lead
— Ground detection with E lead
— Voice transmission through Tip and Ring for transmit and receive
•
Four-wire E & M signaling type I and II, two-way dial repeating (ESN
and Non-ESN)
— echo suppression for type I
— Switchable seven dB and 16 dB for carrier interface for ESN
applications
— Transmit and receive of voice through two separate paths
•
Type I signaling through E & M leads
— Type II signaling
– Near-end seizure with MA/MB leads
– Far-end detection with EA/EB leads
•
Paging trunk loop OAID operation
— Support access by low resistance path at the PA/PB lead.
— All call zone paging is not supported.
•
Two to four-wire conversion of the transmission path
The signaling and control portion of the trunk card works with the CPU to
operate the card hardware. The card receives messages from the CPU over a
signaling channel in the DS30X loop and returns status information to the
CPU over the same channel. The signaling and control portion of the card
provides the means for analog loop terminations to establish, supervise and
take down call connections.
January 2002