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:
Jan. 31, 1978
Filed:
Dec. 16, 1976
Applicant:
Inventors:
David Quon Lee, Chicago, IL (US);
Richard Michael Rovnyak, Schaumburg, IL (US);
Assignee:
GTE Automatic Electric Laboratories Incorporated, Northlake, IL (US);
Attorney:
Primary Examiner:
Int. Cl.
CPC ...
H04M / ;
U.S. Cl.
CPC ...
179 / ; 179 / ;
Abstract
A circuit for electrically preconditioning a telephone line and switching an associated ringing generator on and off at the instant of opportune circuit conditions to eliminate circuit transients. The line circuit is switched by means of a relay so that an equipotential charge exists on either side of the switching contacts at closure and with zero current through the contacts at opening to eliminate suppression devices.