Results of variability observations of the southern extragalactic radi
o sources PKS 1610 - 771, PKS 1830 - 211 and the inner region of Centa
urus A (Cen A) at 1.42 GHz are presented. Different light curves with
temporal resolutions of similar to 30 minutes, 1 day and 1 month were
obtained for each source. Significant variability was detected in PKS
1610 - 771 and Cen A. The implications of these results are discussed.