Re: 122 GHz


Rob, M0DTS
 

I've played with some 3d printed lenses and they work well.
Thet were not designed to any specification just similar shape to the ones found in the flann horns apart from one side is flat.
This shows a small test one giving significant gain at 134GHz, about 13dB if i remember correctly.

A similar one made with 120mm diameter showed over 30dB gain and i used this for some tests on a 10km path successfully.

It's printed with 100% infill so warping occured during print making it difficult.
The fresnel lenses i tried  to print warped too much so i did not get far with that.
Material used was ABS, PLA material was very poor in comparison.

I did plan on making a large version using multiple segments but have not got around to it yet.

No doubt quicker to machine it from solid... my manual parabola turning skills on the lathe are not upto scratch though!

Rob

On Sat, 28 Sep 2019, 18:01 Andy G4JNT, <andy.g4jnt@...> wrote:
What are the options for a 3D printed dielectric lens ?



Virus-free. www.avg.com

On Sat, 28 Sep 2019 at 17:58, Barry Chambers <b.chambers@...> wrote:

Food for thought here but surface finish may be the problem

https://www.hackster.io/abraxas3d/3d-printed-cassegrain-antenna-for-122-ghz-amateur-radio-9ff4d2

-- 

73

Barry, G8AGN

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