Probe head for an NMR spectrometer

A probe head for an NMR spectrometer that provides enhanced signal to noise ratio in NMR measurements. The probe head uses at least a first waveguide to irradiate an NMR sample with an excitation wave and to conduct the emitted sample signal to the preamplifier and subsequent electronic signal processing equipment. The electrical conducting elements of the waveguide are constructed and operated under conditions such that the conductors operate in the regime defined by the anomalous skin effect and preferably in the regime defined by the extreme anomalous skin effect. The reduction in electrical resistance afforded by such construction and operation enables a reduction signal-to-noise ratio in the NMR signal detected by the probe. The invention includes in the preliminary detection circuit means for temporarily matching it with its characteristic impedance.