  We present preliminary results of a campaign undertaken with different radio
interferometers to observe a sample of the most variable unidentified EGRET
sources. We expect to detect which of the possible counterparts of the
gamma-ray sources (any of the radio emitters in the field) varies in time with
similar timescales as the gamma-ray variation. If the gamma-rays are produced
in a jet-like source, as we have modelled theoretically, synchrotron emission
is also expected at radio wavelengths. Such radio emission should appear
variable in time and correlated with the gamma-ray variability.
