  We report on a recent global VLBI experiment in which we study the scatter
broadening of pulsars in the spatial and time domain simultaneously. Depending
on the distribution of scattering screen(s), geometry predicts that the less
spatially broadened parts of the signal arrive earlier than the more broadened
parts. This means that over one pulse period the size of the scattering disk
should grow from pointlike to the maximum size. An equivalent description is
that the pulse profile shows less temporal broadening on the longer baselines.
This contribution presents first results that are consistent with the expected
expanding rings. We also briefly discuss how the autocorrelations can be used
for amplitude calibration. This requires a thorough investigation of the
digitisation and the sampler statistics and is not fully solved yet.
