  We report the results of a pilot multiwavelength survey in the radio
continuum (X, Ka and Q bands, i.e., from 3.6 cm to 7 mm) carried out with the
EVLA in order to confirm the presence of very large dust grains in dusty disks
and torii around the central stars in a small sample of post-AGB objects, as
inferred from millimeter and sub-millimeter observations. Supporting mm-wave
observations were also obtained with CARMA towards three of our sources. Our
EVLA survey has resulted in a robust detection of our most prominent submm
emission source, the pre-planetary nebula IRAS 22036+5306, in all three bands,
and the disk-prominent post-AGB object, RV Tau, in one band. The observed
fluxes are consistent with optically-thin free-free emission, and since they
are insignificant compared to their submm/mm fluxes, we conclude that the
latter must come from substantial masses of cool, large (mm-sized) grains. We
find that the power-law emissivity in the cm-to-submm range for the large
grains in IRAS22036 is nu^{beta}, with beta=1-1.3. Furthermore, the value of
beta in the 3 to 0.85 mm range for the three disk-prominent post-AGB sources
(beta < or = 0.4) is significantly lower than that of IRAS22036, suggesting
that the grains in post-AGB objects with circumbinary disks are likely larger
than those in the dusty waists of pre-planetary nebulae.
