We calculate free-free emission at centimeter wavelengths from jets from Young Stellar Objects (YSOs). We use the x-wind model which is heated and ionized by several physical mechanisms, being of primary importance ionization by x-rays and heating by dissipation of mechanical energy (Shang et al. 2002). With stellar parameters, mass-loss rates, and x-ray luminosities characteristic of Class 0 or Class I YSOs, we recover realistic radio spectral indices and radio maps. In particular, the 3.6 cm flux in models with mass loss rates similar to 10(-6)M(circle dot)/yr are comparable to existing observations of radio jets at 0".1 resolution. Lower mass-loss rates characteristic of Class II YSOs with revealed optical jets generally produce radio jets that are too weak to be detected at current sensitivity levels. We discuss the implications of these comparisons for theoretical models of the YSO outflow phenomenon.
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