5 turn Helical FPV antenna (5.8 GHz)

There are several good 5.8 GHz helical antennas available already, but I wanted one that offered full protection for the wire, was compact and easy to print and did not require using glue for assembly. My design consists of two items that are held together with a single screw. It can simply not get any simpler.

I have also made a 7 turn version of the antenna. That one may be found here: http://www.thingiverse.com/thing:2144979

There are both left and right hand polarized versions of the former and the wire holder. Make sure to print the version you need.

The antenna is inspired by Dave855's designs. I have used his former and parts of his wire holders mixed into my version.

Build Instructions

• The reflector is only a template. Print it and use it to produce a reflector out of PCB material or copper. If you use a PCB, the copper surface must be turned forward, i.e. be the side that the wire holder is mounted to.
• Insert the antenna connector in the out-most hole of the reflector and cut the wire 5-6 mm above the surface.
• Fan out the outer isolation of the antenna wire and solder it to the reflector. There is a picture of this step in the process to make it easy to see what I mean.
• Paint or lacquer the reflector to make it fingerprint proof. This step is purely esthetical and may be skipped.
• Print the holder and the former.
• Use the wire former to create a wire spiral.
• Thread the wire on the holder and cut it to length in place.
• Use an M3 screw and nut to fasten the holder to the reflector.
• The last step is soldering the main wire and the antenna center wire together. To achieve the best results possible the connection to the antenna wire is very important. The main wire should be in parallel with the reflector board for the last 4 mm of it´s length. This section of the wire should be located 2 mm from the surface of the reflector (thanks to Dave855 for the information)