Double Cross Dipole Connectors

thingiverse

These are the joints for a double cross dipole antenna to receive circularly polarized radio waves. I use it in particular to receive from NOAA weather satellites as they pass overhead. The antenna elements themselves are 5/8 inch copper tubing, and they're attached to the antenna holders using 3/8 inch copper couplers. these couplers have a crimp near the end so that the friction fit the elements really tightly, so the bottom elements don't just fall out. The couplers have the coax soldered directly to them, and the connection diagram can be seen in the source PDF. The antenna holders are attached to the antenna hub using PVC pipe that is stiffened with a wooden dowel the same size as the inside diameter. then a hole is drilled into both ends at 30°, so that the elements are held at that angle. then a screw and bolt is used at each connection. here's the PDF that I followed for my build: https://www.qsl.net/l/lu7did/docs/NOAA/DoubleCross_137Mhz%20AntennaMARTES.pdf just as a note, the picture's orientation gets screwed up in thingiverse's image viewer, so if you care about the orientation of the parts, enlarge the image then click view original.