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Rotational spectra of the FeCO and FeNO radicals produced by UV laser photolysis in the vibrational excited states were measured in the millimeter-wave region with the conventional absorption cell at room temperature. The rotational transitions of the FeCO radical in the ground and $\nu 2$ states have been observed by millimeter-wave spectroscopy}, 106, 6820-6824 (1997)}, and the $\nu 1$ fundamental band and hot band from $\nu 2$ state also have been studied by infrared diode laser spectroscopy. In the present work, the rotational transitions ($J$ = 33 - 32 $\sim$ 37 - 36 ) in the $\nu 3$ state of the $X3\Sigma -$ state were observed to split into 3 components due to the spin-rotation and spin-spin interactions. Molecular constants including rotational constant and centrifugal distortion constant were determined by a least squares fitting. The equilibrium rotational constant $Be$ was calculated to be 4373.405(72) MHz from the vibration rotation constant $\alpha 3$ = 20.2051(42) MHz, and previously reported $\alpha 1$ and $\alpha 2$. The bond length between Fe and C, calculated to be 1.725 ${\rm \AA} $ assuming $rCO$= 1.159 $\backslash AA$, agrees well with the {\it ab initio} result, $rFeC=1.722$ \AA}. The 2$\nu 2$ state split into 9 substates due to the vibronic interaction, and the rotational transitions in the $P=0$ component were observed. The rotational transitions of the FeNO radical in the ground and $\nu 2$ states}, and the $\nu 1$ band have been observed in the millimeter-wave and infrared region, respectively. The rotational transitions ($J$ = 28.5 - 27.5 $\sim$ 32.5 - 31.5 ) in the 2$\nu 2$ state of the $X2\Delta i$ state were observed in the present study. The 2$\nu 2$ state ($\Omega =5/2$) splits into 3 substates, $2\Gamma P=9/2,2\Delta P=5/2$ and $2\Sigma P=1/2$, due to the vibronic interaction. The absorption lines in the $2\Sigma P=1/2$ state split into two components because of the $p$-type doubling. The transition in the $\nu 3$ state is now under survey to determine the constant $\alpha 3$ and the equilibrium rotational constant.