Nortel Networks 553-3001-211 manual Trunk circuit features, Trunk unit functions

Page 622 of 894 NT8D15 E&M Trunk card

Trunk circuit features

Trunk unit functions

The functions provided by each unit on the E&M trunk card include 2-wire signaling, 4-wire signaling, and paging operation as follows:

•2-wire, E&M Type I signaling (see Figure 141 on page 623) with:

—near-end seizure and outpulsing with M lead

—ground detection with E lead

—voice transmission through tip and ring for transmit and receive

•4-wire, E&M Type I and II signaling (see Figure 142 on page 624),

2-way dial repeating with:

—echo suppression for Type I signaling

—switchable 7 dB and 16 dB pads for carrier interface

—voice transmission and reception through two separate paths

—Type I signaling through E&M leads

—Type II signaling with near-end seizure by SB/M leads and far-end detection by E/SG lead

•4-wire, DX signaling (see Figure 143 on page 625)

•paging trunk operation (see Figure 144 on page 626) with support access by low-resistance path at the PG/A1 leads

Note: Paging end-to-end signaling is not supported.

553-3001-211 Standard 2.00 September 2004