The Four-Square was developed in the 1980's by Fred Collins, W1FC and Dana Atchley, W1CF (SK), and in conjunction with Steve Davis, K1PEK, formed ColAtchCo. Fred and Dana jointly developed the hybrid for proper phasing. ColAtchCo offered complete systems, including verticals, radial wire, control cable and phasing lines. In the late 1980's, Comtek took Mr. Collins' hybrid further by adding a second toroid, to replace the 180 degree coax and phase correction coax cables. The only coax required are four (4) electrical quarter wave foam 75 ohm and the 50 or 75 ohm line from the transmitter. A Four-Square consists of four verticals spaced one quarter (1/4w) wavelength apart (feedpoints quarter wave apart for 1/2 wave dipole arrays) with the hybrid mounted in the center of the array. The directivity is across the diagonals, selectable in four directions. Many of the top contest stations are employing 4-Square antennas on 160 Meters and 80 Meters, where directional rotary arrays become impractical. The antenna provides up to 5 dB forward gain and 20 to 30 dB front to side / front to back differences. Comtek reports that 40 and 20 Meter 4-Squares are also prevalent. Quarter Wave Verticals have been made with Rohn tower sections, irrigation pipe, push up poles, commercial antennas, and even wire drops from high towers. Most vertical structures require guying. This web site shows an alternative method for building a self supported vertical, free from guy wires, that survives the typical winds experienced in Florida, yet can be easily lowered in the event of impending hurricanes. This antenna is probably not suitable for situations where icing occurs, as the fiberglass will not support icing and remain "vertical".
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