The half-square antenna is a simple 2-element wire phased array. It has modest gain and can be particulary useful on 80 and 160m. Even though the half-square has been with us for a long time, there are still a lot of practical details that are not widely known. These two articles on the half-square antenna give practical details and ways to broadband operation on 80m. half-square antennas for the low bands, 585 kb, Antenna Compendium 5 and broadband half-square for 80 m, 88 kb, Antenna Compendium 5.