AN UPDATED LIST OF RADIO FLUX-DENSITY CALIBRATORS

We present new flux densities in the range 0.7 cm less-than-or-equal-t o lambda less-than-or-equal-to 21 cm for the radio sources in the cali brator list of Baars et al. (1977). Most of these sources show signifi cant variability on the time scale of a decade, with the notable excep tion of 3C286 and 3C295. We use these sources to link our relative mea surements to the absolute scale of Baars et al.; for the other sources we present updated spectra. We assess the suitability of the individu al sources for use as flux density calibrators.