04791660 is referenced by 38 patents and cites 10 patents.

There is disclosed a call announcement circuit integrated into the switching network of a PBX switching system such that the announcement board resides in one of the port slots and has direct access to the internal system buses. The circuit can handle many separate announcements each stored at a selectable compression ratio. Each such announcement can be recorded or played in any of the time slots under processor control. This configuration allows tradeoffs between storage capacity and compression ratio (i.e., speech clarity) and also allows messages to be played on any line or to any station via the communication bus and the selected time slot.

Title
Variable data compression announcement circuit
Application Number
6/901003
Publication Number
4791660
Application Date
August 27, 1986
Publication Date
December 13, 1988
Inventor
Thomas L Smith
Lincroft
NJ, US
Enzo Paterno
Staten Island
NY, US
Kevin J Oye
Red Bank
NJ, US
Agent
David R Padnes
David H Tannenbaum
Assignee
AT&T Information Systems
NJ, US
American Telephone and Telegraph Company
NY, US
IPC
H04M 3/50
H04J 3/02
G10L 3/02
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