qfh antenna

137 MHZ QHF Quadrafilar APT Antenna - This version of the 135mHz quadrafilar antenna for APT reception is an adaptation from Bill Sykes and Bob Cobey's article Taming the QFH which appeared in the March 1997 RIG magazine.

Quadrifilar helicoidal calculator - Calculate design for a quadrifilar helicoidal antenna

QFH antenna for weather satellite band - This article describes how to make a quadrifilar helix (QFH) antenna easily, from inexpensive materials: uPVC plumbing pipe and RG-58U co-axial cable

A quadrifilar helix weather satellite receiving antenna - This article describes how to make a quadrifilar helix (QFH) antenna easily, from inexpensive materials: uPVC plumbing pipe and RG-58U co-axial cable.

Quadrifilar helicoidal antenna - Design your own quadrifilar helix, the site even generates a drilling pattern in a PDF file. Several different construction methods are shown.