QFH 137MHz Antenna

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This antenna serves as a foundation for constructing a 137 MHz NOAA satellite reception system using the structure of a quadrifilar helicoidal design. Calculations were completed utilizing Mr. John Coppens' online QFH antenna calculator: http://www.jcoppens.com/ant/qfh/calc.en.php Additions Made in April 2015: A photograph taken today demonstrates successful antenna reception with the antenna, featuring the SDR RTL2832U dongle as its only interface. Instructions for Building this Antenna This structure cannot be printed all at once; instead, divide it into eight distinct parts: QFH137mhz_V2_cut1 - cut8 provided for convenience. Print each part sequentially in order (cut1 to cut8), taking care that the first piece serves as the top component of the finished structure. Gathering Pieces: Print and cut all the pieces. I recommend gluing each layer starting from the top portion. I have used epoxy, however a good contact will suffice. Final Preparation: * Insert a wire for both layers on the center cylinder in part 7. The next step is to insert a 75 Ohm coaxial TV cable within the center of the structure due to its similarity with standard TV antennas. Assembly Process For added precision and performance, I drilled two holes into cut1 where the wire can be securely anchored to the base (choke balun). Assembling the Wire Loop Insert copper wires into these slots to establish a pattern resembling the pictures I've attached. Complete one loop at a time by drilling the opposing arm and moving in an upward motion. When finished, you should see both patterns connected from top to bottom of the antenna. Completing Construction: You now need to attach your wire connections with the remaining ends that remain sticking outwards to ensure smooth flow of data during transmissions or when communicating back from a signal station or any such device installed within this particular setup described herein. Assembly Please review our other sections as we have created additional images, providing clarity about certain tasks mentioned here. Also: Check http://www.gregorystrike.com for even more pictures!