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:
Nov. 30, 1982
Filed:
May. 05, 1980
Applicant:
Inventors:
Edward G Johnson, Woodbridge, GB;
Adrian J Morgan, Framlingham, GB;
Assignee:
The Post Office, London, GB;
Attorney:
Primary Examiner:
Int. Cl.
CPC ...
H04R / ; H04R / ;
U.S. Cl.
CPC ...
1791 / ; 179 / ; 307400 ;
Abstract
An electroacoustic transducer for a microphone comprises an electret wherein an additional capacitance substantially greater than the capacitance normally inherent in the electret is connected in parallel with the electret. The additional capacitance may be of the order of 10 times greater than the capacitance normally inherent in the electret and may be produced inherently in the transducer or by a separate component connected to the transducer.