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:
Oct. 20, 1987
Filed:
Apr. 30, 1986
Applicant:
Inventors:
Reginald A Willard, Middlesex, GB;
William S Percival, London, GB;
Assignee:
National Research Development Corporation, London, GB;
Attorney:
Primary Examiner:
Assistant Examiner:
Int. Cl.
CPC ...
G01R / ;
U.S. Cl.
CPC ...
324322 ; 324303 ; 307262 ; 307555 ; 328223 ;
Abstract
Nuclear magnetic resonance is excited in surrounding fluids by pulsing a first winding which with a capacitor forms a resonant circuit. In order to observe signals induced by NMR in the first winding between pulses, the pulses are attenuated by connecting resistors across a second winding inductively coupled to the first winding. Connection of the resistors is made when required by forward biasing two MOSFETs connected 'back to back' to reduce transients when the MOSFETs cease conduction. A switching pulse for the MOSFETs which has a steep rising edge and an exponential trailing edge has been found advantageous.