The rubber ducky antenna (or rubber duck aerial) is an electrically short monopole antenna that functions somewhat like a base-loaded whip antenna. It consists of a springy wire in the shape of a narrow helix, sealed in a rubber or plastic jacket to protect the antenna. Rubber ducky antenna is a form of normal-mode helical antenna.
Electrically short antennas like the rubber ducky are used in portable handheld radio equipment at VHF and UHF frequencies in place of a quarter wavelength whip antenna, which is inconveniently long and cumbersome at these frequencies. Many years after its invention in 1958, the rubber ducky antenna became the antenna of choice for many portable radio devices, including walkie-talkies and other portable transceivers, scanners and other devices where safety and robustness take precedence over antenna capabilities.
Two rumors link the naming of the antenna with the Kennedy family. In the early 1960s the rubber ducky became the antenna of choice for personal walkie-talkie transceivers used by police and security services, including the U.S. Secret Service, which guards the President of the United States. According to one rumor, the young Caroline Kennedy, daughter of President John F. Kennedy, named the flexible device when she pointed at one on an agent's transceiver and said, "rubber ducky". On the other hand, Dr. Thomas A. Clark, a senior scientist with NASA, claims to have named it after listening to one of Vaughn Meader's comedies about the Kennedy family.