  AA Dor is an eclipsing, close, post common-envelope binary (PCEB). We present
a detailed spectral analysis of its sdOB primary star based on observations
obtained with the Far Ultraviolet Spectroscopic Explorer (FUSE). Due to a
strong contamination by interstellar absorption, we had to model both, the
stellar spectrum as well as the interstellar line absorption in order to
reproduce the FUV observation well and to determine the photospheric parameters
precisely.
