As a newly licensed Ham Radio Operator, I was ready to move beyond a handheld radio and be able to extend my range. Since most of the Technician Class License privileges are in the 2M / 70 CM bands, a base station in that range made the most sense to get started. There is a lot of DIY tradition in the Ham Radio community and having a 3D printer made some of the construction easier.
The bottom is a mount for a 3/4′ PVC pipe and the top pieces (4) are used to steady the radiator and support the ground elements. The MKII version of the ground plane was not published when I put this together but I think I would not have needed the base cap.
The element are brass welding rod from Harbor Freight Tools. Using the calculator link below, I worked out the main radiator is cut to 19.5′ and I over sized the ground elements to 20′. All elements are soldered to a SO-239 chassis connector and then painted. Once the paint dried, I applied a thick coat of silicon sealant to waterproof the antenna.
I have the PVC attached to a 20″ section of fencing top rail as a mast and all connected together with LMR-400 coax. Performance with this has really impressed me in that I am able to get a good signal into the repeaters in my area which is a 22 to 30 mile line of sight trip. Full quieting even.
Resources:
Antenna Calculator – http://www.buxcomm.com/ground_plane_calculator.htm
3D Printer Patterns:
- 1/4 Wave Ground Plane Antenna Mk I – https://www.thingiverse.com/thing:2780322
- 1/4 Wave Ground Plane Antenna Mk II – https://www.thingiverse.com/thing:2854880
- Mount for low-cost 2m ground plane antenna – https://www.thingiverse.com/thing:670821