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. 09, 1994
Filed:
Sep. 19, 1991
Applicant:
Inventor:
Bruce E Hofer, Portland, OR (US);
Assignee:
Audio Presicion, Beaverton, OR (US);
Attorney:
Primary Examiner:
Int. Cl.
CPC ...
G01R / ; G01R / ;
U.S. Cl.
CPC ...
324115 ; 3241581 ; 324 731 ; 3241 / ;
Abstract
An ac mains test apparatus and method. An audio frequency signal measurement instrument is provided with a circuit for testing the ac mains to which the instrument is connected. The ac mains is internally connected to a coupler which presents an attenuated portion of the ac mains to the low level input of the instrument. A switch is provided for selectively connecting the input either to an audio signal to be measured or to the ac mains portion. The coupler both attenuates the ac mains for input to the instrument and isolates the relatively high ac mains voltage from the low level input.