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:
Sep. 03, 1996
Filed:
Jul. 10, 1995
Spectrospin AG, , CH;
Abstract
A method for tuning of the probe head impedance (Z.sub.x) of an NMR receiver coil having a receiver circuit for an NMR signal with which, by means of an RF tuning signal (3), the probe head impedance (Z.sub.x) is tuned via a first reference signal produced with real reference resistance (R.sub.0) at one location M2 within the receiver circuit is characterized in that a reference impedance (Z.sub.0) is matched at an arbitrary location in the path of the RF tuning signal (3) in the receiver circuit (10; 11) in such a fashion that a second reference signal corresponding to the first reference signal at location M2 occurs at location M2 and that subsequently, the probe head impedance (Z.sub.x) is tuned to the second reference signal at location M2. In this fashion, in the path of the NMR signal at the input to the preamplifier, the number of necessary diodes, RF chokes and other components, which can lead to signal losses, is minimized. Furthermore, in the path of the NMR signal at the input to the preamplifier during normal operating conditions, all diodes which are located here are in a non-conducting state and there are no diodes in series with the path of the NMR signal.