Nortel Circuit Card Installation Manual page 603

Recorded announcement trunk operation
Note: Refer to "Multi-Channel RAN modes" on
information on Multi-Channel RAN modes, which are not linked to a
RAN machine or a given trunk.
When configured for Recorded Announcement (RAN) operation, a trunk unit
is connected to a customer-provided recorded announcement machine.
Announcement machines must be compatible with RAN trunks. Use the
manufacturer's instructions to set up the Announcement machines.
Each trunk unit provides the following for operation with RAN equipment:
• pulse start, level start, or continuous operation modes
• selectable termination of tip and ring leads into 600 or 900 ohms for
interface with a low-impedance (2 or 4 ohms) source
• connection of up to 24 trunk units to a single announcement machine
channel
Recorded announcement machines
Recorded announcement machines store prerecorded voice messages that are
played back to the trunk units to which they are connected. Most
commercially available announcement machines store recordings digitally,
although some drum and tape units are still in service.
An announcement machine can provide one or more channels and each
channel may be prerecorded with a different message. Some announcement
machines also provide a Special Information Tone (SIT) capability. These
tones are inserted at the beginning of intercept messages such as "Your call
cannot be completed as dialed. Please check the number and try again."
Figure 138 on
announcement machine channel to unit 0 on a universal trunk card.
NT8D14 Universal Trunk card
page 604 shows a typical connection from a single
page 605
Circuit Card Description and Installation
Page 603 of 906
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