250 GHz observations of Be stars

New 250 GHz flux density measurements with the 30 m telescope at Pico Velet a are presented for 23 Be stars. We suggest that the radio spectral index i s typically close to 1.4 for these stars. We present in a discusssion of ow n and literature data some evidence that in few cases slow variations with a time scale of about a year occur. Both evidence is compatible with the id ea that there is no stellar activity type radio emission of Be stars but a maybe slightly modulated quiescent radiation of the outer parts of selfsimi lar circumstellar disks. An immediate improvement of existing models is not possible.