An antenna is disclosed for use in emitting the signals in times of conflict to overcome jamming. The antenna comprises a reflector having a focal point and a central support shaft extending axially from the reflector on bore through the focal point. First and second selectable, multi-turn axial mode helical antenna elements are disposed on-bore on the central support shaft, spaced linear from each other, and wound to have the same polarity. One of the helical antenna elements is disposed at the focal point, and the other helical antenna element is disposed at a defocused position to broaden a transmit energy beam and area of regard.