Wednesday, November 10, 2021

 3D printed Collinear ant for 2m & 70cm (APRS & LoRa)








I am playing with the LoRa APRS for some time. It is quite a funny what a DX you can have with a few mW of RF power. I had some X30 and X50 antennas and I was thinking about something more powerful. Collinear antennas are a good choice and when my friend did drawing of dipole holders for me, I could just simply printed it. Building of antenna was a question of one Sunday. There is simly drawing. 
There are STL files for 2m and 70cm version. It is designed for 30mm main pipe and dipoles are made from 10mm (2m) and 8mm (70cm) Al Pipe.

There are dimensions of the dipoles. Final SWR was under 1:1,1 at 145 MHz and 1:1,2 at 434 MHz:


And examle of instalation at OK2ZAW-17 solar powered DiGi in the Eagle Mountains 1100m asl.



2 comments:

  1. Hi, have a question - what is the element length, i mean aluminium pipe for 144 dipole?

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  2. rougly 2 x 50cm dipole is 1/2wl, little shorter, WL is little over 2m so I got mine @ 49.8cm and works fine.

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