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. 16, 1981
Filed:
Mar. 26, 1979
Michael C Cowpland, Ottawa, CA;
Patrick R Beirne, Stittsville, CA;
Mitel Corporation, Kanata, CA;
Abstract
A multifrequency dialing tone to 2/8 decoding circuit which does not require individual filters for distinguishing individual tone frequencies. The circuit converts the period of each of the received multifrequency signals to individual voltage amplitudes which corresponds thereto, then compares the voltage amplitudes with a predetermined plurality of voltage ranges. Correspondence of a voltage amplitude level with one of the ranges causes production of an output signal, signifying the presence of a particular acceptable multifrequency tone. Individual correspondence signals operate latches which apply signals to decode leads which carry the decoded output signal.