MWC 560: jets or optically thick expanding envelope?

Results of high- and low-resolution spectral and UBV photometric observations of MWC 560 during 1990 January-October are presented. Strong variations in the star brightness compared with previously published observations are discussed. The presence of flickering activity from the U-band monitoring observations is also noted. The most remarkable features in the spectra obtained during 1990 January-April are the strong violet-shifted Balmer absorption components with velocities of up to ∼ -6000 km/s visible up to about H 20 -H 21