An E-Band (60-90 GHz) chirped-pulse Fourier transform millimeter-wave spectrometer has been constructed for eventual kinetics and dynamics studies. The performance of the spectrometer is demonstrated with the molecule nitroxyl (HNO). Using the new spectrometer and by passing isotopically labelled methyl nitrite (CH3ONO) through a pyrolysis nozzle, the spectra of minor isotopologues of HNO have been obtained. The observations on the isotopologues identified here, (HNO)-N-15, (HNO)-O-18, and (DNO)-N-15, have been combined with the earlier isotopic observations, HNO and DNO, to create a global 4,11 HNO geometry that approximates an equilibrium structure. The results are compared to high-level ab initio calculations. (C) 2017 Published by Elsevier B.V.