A reflector antenna includes a feed configured to always point during operation in a direction that opposes ingress of water into the feed, and a reflector having a truncated spherical reflecting surface, wherein a relative orientation of the reflector and the feed is adjustable. Another reflector antenna includes a feed configured to always point during operation in a direction that opposes ingress of water into the feed, and a reflector spaced apart from the feed by a focal length at least as great as a diameter of the reflector. Another reflector antenna includes a feed and a reflector having a truncated spherical reflecting surface, wherein the reflector is spaced apart from the feed by a focal length at least as great as a diameter of the reflector.