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.
Patent No.:
Date of Patent:
Jul. 30, 1985
Filed:
Feb. 04, 1983
Applicant:
Inventors:
Magdy H Keriakos, Kanata, CA;
Stanley D Rosenbaum, Ottawa, CA;
Assignee:
Northern Telecom Limited, Montreal, CA;
Attorney:
Primary Examiner:
Assistant Examiner:
Int. Cl.
CPC ...
H04B / ;
U.S. Cl.
CPC ...
1791 / ; 179 77 ; 333216 ; 333217 ;
Abstract
Communication lines for example telephone loop circuits are typically terminated with line feed circuits such that d.c. and a.c. terminating impedances are dissimilar. The line feed circuit includes tip and ring feed resistors of similar ohmic values for supplying the communication line with energizing current. An a.c. terminating impedance of greater ohmic value than the d.c. terminating resistance is provided by a negative impedance circuit which is a.c. coupled across the communication line, in shunt with the feed resistors.