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. 22, 1980
Filed:
Jul. 18, 1978
Applicant:
Inventors:
Stephen E Kerman, Merrick, NY (US);
Fumikazu Hamatani, Kawasakishi, JP;
Fumio Tsutsumi, Tkasakishi, JP;
Yuji Tanaka, Kawasakishi, JP;
Assignees:
Nippon Tsu Shin Kogyo K.K., Kawasaki, JP;
TIE/Communications, Inc., Stamford, CT (US);
Attorney:
Primary Examiner:
Assistant Examiner:
Int. Cl.
CPC ...
H04M / ;
U.S. Cl.
CPC ...
179 / ; 179 / ; 179 / ;
Abstract
The disclosure is directed to a calling circuit which controls the connection of two different audio signal sources to a single audio signal transmission path for broadcasting the audio signals over a telephone set loudpseaker as well as controlling the energization of indicators in the telephone set and at the main control circuit. Only four conductors are used to connect the telephone set with the main control circuit, two of which are power supply conductors which may supply other circuits as well.