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:
Aug. 29, 1978
Filed:
Jul. 20, 1977
Applicant:
Inventor:
Joe F Guess, Cedar Rapids, IA (US);
Assignee:
Conrac Corporation, Stamford, CT (US);
Attorney:
Primary Examiner:
Assistant Examiner:
Int. Cl.
CPC ...
H04M / ;
U.S. Cl.
CPC ...
179 / ; 179 / ; 3311 / ;
Abstract
Communication units for hand-held use, combining a microphone for voice communication with means for generating at least two code frequencies for signaling, are made more compact and economical by dual capability of a single amplifying circuit in oscillating mode for tone generation and in substantially linear mode for amplifying the microphone output.