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We report the application of polarization quantum beat spectroscopy (QBS) to probe the hyperfine structure of single $NO2$ molecular eigenstates in the region $2.5cm-1$ below dissociation threshold $(D0=25128.57cm-1)$. The hyperfine interaction is substantially weaker than that found at energies below $22000cm-1$, but is similar on average to that observed $50-100cm-1$ below threshold. The ratio of $J=3/2$ to $J=1/2$ levels is much larger than that expected on the basis of complete rovibronic mixing, but is consistent with a previous study.