The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.

The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.

Date of Patent:
Jun. 16, 1998

Filed:

Oct. 17, 1996
Applicant:
Inventors:

David Jeffrey Westergaard, Calgary, CA;

Robert Barrie Turnbull, Calgary, CA;

Timothy Augustus Kuechler, Calgary, CA;

Aaron James Bobick, Calgary, CA;

Assignee:

Northern Telecom Limited, Montreal, CA;

Attorney:
Primary Examiner:
Assistant Examiner:
Int. Cl.
CPC ...
H04M / ;
U.S. Cl.
CPC ...
379413 ; 379142 ; 379215 ; 379258 ; 379399 ;
Abstract

A circuit for use with a SCWID adjunct to remove A.C. in-band signaling tones from the voice path to a telephone apparatus serially connected to the adjunct. The A.C. signal component is carried on top of the D.C. voltage used to power the telephone. The circuit includes means to monitor the D.C. voltage level and to pass this voltage substantially unchanged to the telephone. The A.C. signal in the form of a FSK tone, received from the central office, is used by the adjunct to provide a subscriber with call feature information such as the identity of a calling party while the telephone is off-hook.


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