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. 28, 1995
Filed:
Jan. 29, 1993
Applicant:
Inventor:
Ziyad H Doany, Austin, TX (US);
Assignee:
Primary Examiner:
Assistant Examiner:
Int. Cl.
CPC ...
G01V / ;
U.S. Cl.
CPC ...
324326 ; 324 67 ; 324233 ; 324243 ;
Abstract
An apparatus for locating obscured conduits, such as buried cables, employs a novel signal processing technique to increase the sensitivity of the apparatus, particularly in congested areas. The cable locating apparatus is similar to prior art dual-peak detection devices which compare signals from two parallel induction coils, but a phase shift is introduced into one of the signals prior to the comparison. This phase shift serves to minimize the effects of side minima in the response curve of prior art dual-peak devices. This effect is enhanced by adding a gain mismatch to the two detected signals. The locator preferably operates with analog signals to reduce expense.