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:
Jun. 07, 1977
Filed:
Dec. 22, 1975
Applicant:
Inventors:
Andrew Ernest Brennemann, Ossining, NY (US);
Suk Suet Soo, Ossining, NY (US);
Assignee:
International Business Machines Corporation, Armonk, NY (US);
Attorney:
Primary Examiner:
Int. Cl.
CPC ...
H04M / ;
U.S. Cl.
CPC ...
179 / ; 179 / ;
Abstract
This invention relates to apparatus for automatically connecting computer terminals and the like to telephone lines and further includes means for automatically analyzing telephone line call progress signals indicative of line status. The apparatus includes a band pass filter, variable gain amplifier, AM detector, a wave shaper, a signal cadence detector and means responsive to said cadence detector for indicating line status.