A turnstile antenna element and balun for use in a phased array are described. The antenna includes a plurality of stacked bowtie radiators. Each stacked bowtie radiator includes a driven conductor and a passive conductor separated by a dielectric. The balun includes a central member having dielectric slabs symmetrically disposed on external surfaces thereof. At least one end of the balun is provided having a shape such that conductors on the dielectric slabs of the balun can be coupled to the driven radiator conductors.