  We calculate the emission of protoplanetary disks threaded by a poloidal
magnetic field and irradiated by the central star. The radial structure of
these disks was studied by Shu and collaborators and the vertical structure was
studied by Lizano and collaborators. We consider disks around low mass
protostars, T Tauri stars, and FU Ori stars with different mass-to-flux ratios
$\lambda_{\rm sys}$. We calculate the spectral energy distribution and the
antenna temperature profiles at 1 mm and 7 mm convolved with the ALMA and VLA
beams. We find that disks with weaker magnetization (high values of
$\lambda_{\rm sys}$) emit more than disks with stronger magnetization (low
values of $\lambda_{\rm sys}$). This happens because the former are denser,
hotter and have larger aspect ratios, receiving more irradiation from the
central star. The level of magnetization also affects the optical depth at
millimeter wavelengths, being larger for disks with high $\lambda_{\rm sys}$.
In general, disks around low mass protostars and T Tauri stars are optically
thin at 7 mm while disks around FU Ori are optically thick. A qualitative
comparison of the emission of these magnetized disks, including heating by an
external envelope, with the observed millimeter antenna temperature profiles of
HL Tau indicates that large cm grains are required to increase the optical
depth and reproduce the observed 7 mm emission at large radii.
