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The feasibility of selectively recording the line transitions of paramagnetic species using Fourier transform spectroscopy has been demonstrated recently [1]. Essentially the fringe variation producing the interferogram signal is not due to the path difference modulation but to the spectral shift of the lines of interest. In the particular case of paramagnetic species this shift is obtained by applying a magnetic field to the sample. The technique is widely known in laser spectroscopy as `Laser Magnetic Resonance'. In both FTS and LMR spectroscopies it requires high resolution capabilities. This paper reports low resolution Zeeman modulation absorption spectra of NO recorded with a Fourier transform interferometer. Only the lines corresponding to transitions between the $\Omega =3/2$ levels are detected. The observed phenomena is essentially understood as due to the variation of the equivalent width of the lines with their splitting by the magnetic field. The absorption process must be in the non linear domain. When this condition is fulfilled, this lineshift modulation has the advantage of being accessible to low resolution techniques. It is likely usable for convenient concentration measurements. Because low resolution runs may be rapidly performed, it may also clearly save time when for instance, the functioning of a source producing unstable species is monitored by a Fourier transform spectrometer.