13cm S-Band Helical Antenna

13cm S-Band Helical antenna

Since the antenna has to go on the satellite mast, and there is not much room for a dish, I decided to start off with a Helical antenna.
I have build several in the past, and took the design from VE2ZAZ
Back in 2005-2007 I had good experience with this helical design, so I did not hessitate and started to build one again.
Only with some more Turns, to be precise 34 turns.. (That is what you max get from a roll of 5m 6mm2 wire from the store 🙂
Theoretical gain of 19dBI
After building this helical, I have set it up for testing, and the SWR was good enough 1/1.3 on 2400MHz 🙂 so no tuning needed further here..
I have made a drawing of my antenna, please refer to VE2ZAZ’s design for specific dimensions..

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Some detailed pics of building the Antenna..
First I started to make the Reflector plate with the N Connector
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A Detailed shot of the dielectricum of the N-Connector, That is cutoff at approx 1,2mm above the Reflector surface.
As you can read on the website of VE2ZAZ the coupling Tab needs to start off at this point..

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All mounting is done with Stainless steel hardware! Never using anything other!
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Drilling/Milling the standoff mounting points.. note that the standoffs start off from the inside.
13cmhelical1Detailed picture of the standoff mounting hole.
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These cabinet handles are perfect material for making standoffs!, they are 10mm in diameter.
Tip for dutch hams, buy them at Praxis, they have 4 in the bag for a good price 😉
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Detailed shot of the finalzed standoff, note the hole!, the wire is 2.9mm the hole is drilled at 3.5mm..
This because the wire is bend in a radius, so drilling it with 3mm will not fit!13cmhelical8The helical is wound on a 40mm PVC pipe.. when done and stretched out to the correct spacings, the diameter will just perfectly shrink down to the desired diameter 😉13cmhelical6
Detailed shot of the helical wound thru a standoff
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Detailed shot of the finalzed standoff, note the hole!, the wire is 2.9mm the hole is drilled at 3.5mm..
This because the wire is bend in a radius, so drilling it with 3mm will not fit!13cmhelical8The helical is wound on a 40mm PVC pipe.. when done and stretched out to the correct spacings, the diameter will just perfectly shrink down to the desired diameter 😉13cmhelical6
Detailed shot of the helical wound thru a standoff
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Detailed shot of the helical and coupling tab that is going to be soldered to the N-Connector
13cmhelical10Detailed shot of the helical and coupling tab that is going to be soldered to the N-Connector13cmhelical11
Voila a 13cm Helical for S-Band use 🙂
Tip!, Spray paint the antenna with an Acryllic blanc paint, this for protecting the copper helical.13cmhelical9