NT8D14 Universal Trunk card Page 591 of 894

Recorded announcement trunk operation

Note: Refer to “Multi-Channel RAN modes” on page 593 for 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 135 on page 592 shows a typical connection from a single announcement machine channel to unit 0 on a universal trunk card.

Circuit Card Description and Installation

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Image 591
Nortel Networks 553-3001-211 manual Recorded announcement trunk operation, Recorded announcement machines