A method of manufacturing a microwave ablation device, the method including applying a balun short circumferentially about an outer conductor of a coaxial feedline and applying a dielectric material circumferentially about the outer conductor of the coaxial feedline and in contact with the balun short to form a balun. The method further including extending a temperature sensor along the coaxial feedline such that the sensor contacts the balun short, securing the temperature sensor to the coaxial feedline with a first heat shrink material, and securing the dielectric material, balun short, and temperature sensor in contact with each other and to the coaxial feedline using a second heat shrink material.