Page392 of 544 NT8D15E&M TrunkCard
553-3011-100 Standard14.00 January 2002
Trunk circuit features
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
Signaling and control
The signaling and control portion of the trunk card works with the CPU to
operate the card hardware . The card receives mes sages from the CPU ove r a
signaling channel in th e DS30X loop and return s status information to th e
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.