An Improved Cw Nmr Broad-line Spectrometer Forweak Signal Detection
نویسنده
چکیده
In the article there is described a frequency-sweep nuclear magnetic resonance (NMR) spectrometer when a static magnetic field runs at a fixed value. The repetitive frequency-sweep of oscillator is realized by a variable frequency divider in the feedback loop of the second-order Phase Locked Loop. The largest advantage of this system for the CW NMR spectrometer is a good possibility of repetitive passages over resonance in case when NMR signal is very weak and the S/N ratio increase is necessary. The experimental results show that this system with the low-noise NMR oscillator is very useful for th et detection of the broadline NMR signals.
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