Machalski and Engels (1994) have drawn attention to the recent outburst in the extragalactic radio source 1308+328. We observed it with VLBI at 2.3 and 8.4 GHz in February 1995, using the EVN, and including antennas at Seshan, Kashima, Hartebeesthoek and Ny-Alesund, all of which provided long baselines. During these observations we switched every few minutes between 1308+328 and the nearby compact source 1308+326, 14 arcmin away. This allowed us to determine a precise relative separation between these sources at both frequencies using phase referencing techniques, and provided a useful comparison between source sizes. We found that the target source, 1308+328, is considerably more compact than the reference source 1308+326, the latter being resolved (correlated flux decreased by 50 %) at 8.4 GHz at 250 million wavelengths. In contrast, 1308+328 appears completely unresolved at this resolution (Fig 1), corresponding to a source size < 0.5 mas.