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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 low-cost, easy-to-build Quadrifilar Helix (QFH) antenna for weather satellite reception using uPVC plumbing pipe and RG-58U coaxial cable. Unlike traditional designs requiring copper pipe and plumbing skills, this approach enables construction with basic tools and minimal technical expertise. The antenna's shorter, wider proportions favor higher elevation angles, reducing interference from horizon-level pager transmitters. Electrical connections are simplified at the antenna's apex, with the coaxial cable forming the radiating elements. Testing demonstrated consistent signal strength throughout satellite passes, proving effective weather satellite reception is achievable without precision engineering to sub-millimeter tolerances.

This version of the 135MHz quadrifilar 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.

The purpose of this page is to provide information and links about Quadrifilar Helix Antennas. It's the best antenna to use for APT satellite reception

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

This is an antenna that author just built. Was intend for receiving the AO-27 downlink (at 436.800 +/- doppler). It is built with right hand circular polarization, and the gain is supposed to be in the neighborhood of 3 DB.

Article about quadrifilar helix antennas, electrical and physical characteristics, difference between quadrifilar and conventional helix antenna

A Quadrifilar Helix Antenna for 137 MHz By George Goodroe, KF4CPJ

A page dedicated to the Quadrifilar Helical Antennas, with projects, pictures and antenna plans by OH2GVB

How to build a QFH (Quadrifilar Helix Antenna) to download images from weather satellites. A complete tutorial on assembling QFH antenna at home with simple and common tools

The Quadrifilar Helical antenna provides circular polarization and complete hemispherical reception, which is precisely what is needed to receive the polar orbiting weather satellites, and as a 2 meter antenna it will receive horizontal, vertical and clockwise circular polarization.

This version of the 137MHz quadrifilar antenna for APT reception is an adaptation from Bill Sykes and Bob Cobey Taming the QFH which appeared in the March 1997 RIG magazine. This article contains detailed 3D pictures and models and detailed pictures.

This project details the construction of a compact, circularly polarized Quadrifilar Helix Antenna (QHA) designed for 146 MHz operation. The antenna features a 1/2λ1/2λ helical design with a 2.6:1 aspect ratio, providing 4.5 dB gain and a spheroid radiation pattern. It is ground plane independent and compatible with both vertical and horizontal polarizations, making it ideal for terrestrial and space communications. The design includes step-by-step instructions for building the antenna using readily available materials like aluminum rods, PVC pipes, and RG-58 coaxial cable. The antenna's performance has been validated through comparisons with commercial omnidirectional antennas, showing superior results.

This page provides information and links about Quadrifilar Helix Antennas, the best antenna for APT satellite reception. It explains the basic design and configuration of QHA, including the research and developments that have been made over the years. The page offers insights into the radiation patterns and benefits of using QHA for APT ground stations, with examples of polar diagrams. If you are interested in learning more about QHA and its applications, this page is a valuable resource.