The spectroscopic orbits and other parameters of the symbiotic binary FN Sgr

We present an analysis of optical and near infrared spectra of the eclipsing symbiotic system FN Sgr. In particular, we have determined for the first time spectroscopic orbits based of the radial velocity curves for both components. A set of blue absorption lines resembling an A-F type star is present in all our spectra. They seem to be associated with the hot component but the best orbital fitting corresponds to a larger eccentricity. We have also studied spectral changes and photometric variations in function of both the hot component activity and the orbital motion.