LoRa Ground Plane Antenna 868MHz

thingiverse

# LoRa Ground Plane Antenna 868MHz This design is inspired by [dedehai's](https://www.thingiverse.com/dedehai) simulations for his [LoRa antenna jig](https://www.thingiverse.com/thing:2849393). The antenna was tested bridging 1.5km passing some forest and one building. I am happy about comments of distance tests. Best return loss ratio measured with the VNA was 1:1.02. The antenna has an inward stub as a mounting aid. # Materials - 1.3mm thick copper wire (can also be thicker) like standard power cable - Copper tape with electrically adhesive backside ([like this](https://www.amazon.de/gp/product/B01I1XNY1E)) - SMA-KY socket [like this](https://a.aliexpress.com/_uxARIR) # Drilling The markers on the top help you drilling a hole for the SMA-KY mount. Start with 2mm, increase to 5 and finally use 6.5mm. Drill in "inverse" rotation so that you melt the PETG. This reduces splinting the material. # Adding Radials The radials are made from copper tape with a conductive adhesive backside. I cut them 1cm wide and 9cm long. Use the markers on the top and the bottom of your print to place the stripes with better accuracy. See that some of the copper covers the hole drilled before. Finally use a knife to cut a cross into the area where the socket will be placed. # Placing the socket Solder a 10cm long copper wire to the feeding line of the socket. If you have no tuning equipment like a spectrum or vector network analyzer, you may try a 86mm long copper wire instead. But be aware that then your antenna will not work with optimal efficiency. Place the socket into the hole and screw it tight from the backside. Assure yourself that the radials and the socket are in good contact. When fine, you may add some glue to prevent losening. # Tune Tune the antenna by cutting small pieces off the 10cm copper wire radiator.