More Helical Madness

It occurred to me that one should be able to ship a usable antenna in say, a mailer at media mail rates. Why not? Just cut down on the bulk. And, in the process, make it interesting with some educational elements.

So, how do we turn 4 sheets of paper, some foil, some cardboard, some copper tape and Scotch tape, into something useful?

Pretty easy.

  1. Some taping
  2. Some cutting
  3. Enjoy



The feedpoint/match with 1/4 turn at ~1mm above the groundplane:

and the pre-angled ~51 degree elevation base for my latitude

and it can all fit into a media rate mailer

and it works fine as a indoor window antenna.

Another permutation might be to slap the foil onto the Outernet box top and go from there…

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@k5ted

now THAT is what Im talking about!!! Absolutely fantastic job and great illustration and inspiration!!
Thank you for this post!
I wonder how hard it would be to transfer that design and “Pre-print” the paper with guides for the tape?

Beautiful @k5ted.

Is that RSSI - SNR without the preamp? I am guessing that it is. The overall length looks shorter than yours @ki4its.

-Cecil
AA5CE

That’s with preamp. It’s about 2-3dB better than the patch, indoors, behind screen, glass and blinds.

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Well done . This is exactly what we need. Plus these are excellent photos very clear.

Easy to do. That one is built from a photocopy set of the originals I drew on 24# paper. It has all the markers and guides. Photocopies are generally within 1mm or so and are adequate. I have the template in a pdf if you want it

This is really inspiring. How difficult is it to point?

not all all.

@k5ted
I would love these plans. Heck, I would love for you to upload them for all!! I assume from the pictures that this is 5 turns at the center frequency?

Mind if I throw a challenge at you? How about making a patch out of aluminum foil and Styrofoam?

Here are the dimensions that I confirmed with Adam 9A4QV

170mm x 170mm ground plane
98mm x 98mm element
***21mm diagonol cuts; 21mm is the distance from the corner, so 98-21 mm
25mm–connection point of element and ground plane
7mm spacing between element and ground plane

@Syed

LOL you are reading my mind.

lol… that was already my weekend project. I have some packing foam that is EPP foam. Not sure how it will act, but worth a try

4 turns

I will point out,though, that best case, this will underperform the Outernet patch mainly because Adam’s design is two elements, which makes for a very broad pattern with little gain. Great for high power sats maybe not great for this application. Happily, adding the director element should be simple.

What about adding two more directors?

will have to look at patch antenna theory to see if that will work

Some things to mull over…

Stacked Microstrip Antenna with High Performances

Generally a microstrip antenna has a narrow-band and low gain of 6-7dBi.
By stacking a parasitic patch as shown in figure 5, the wide-band or high gain characteristic is obtained.
the characteristics are depend on the element distance hp.

Fig.5 Stacked Microstrip Antenna

The behavior mechanism of the stacked antenna is synthetically clarified for the first time by investigating the results calculated by using FDTD method.
The stacked microstrip antenna has particular characteristics that are a high gain or a wide bandwidth.
When the size of parasitic patch is nearly equal to the fed patch and the distance between the fed patch and the parasitic patch is about0.1 wavelength, the bandwidth is increased.
When that distance is about a half wavelength, the gain enhancement is obtained.
These characteristics have been reported individually with limited range, so far.

a three-element stacked microstrip antenna with a wide bandwidth and a high gain is successfully proposed.
The three-element stacked microstrip antenna is composed of a fed patch and two parasitic patches.
The parasitic patch close to the fed patch increases the impedance bandwidth, and the other parasitic patch located in half a wavelength from the fed patch enhances the gain.

Fig.6 3-Element Stacked Microstrip Antenna with Wide-Band and High-Gain Performances
http://www.ceng.ec.saga-u.ac.jp/mwel2012/research/msa-e.html

Paper helix signal is good this morning, just sitting in the window… Valid packets look good after being up all night.

Here’s the link for the templates. Let me know if you have success with it. The copper tape is not essential, and you can use very thin wire instead, #26 or less to maintain the roll tightness. Use some glue or double sided sticky tape around the center of the cardboard to keep the foil from lifting with the weight of the tube, or instead, put the foil on the backside of the cardboard.

The copper tape I used is from Hobby Lobby, with the store coupon it was $4.19 for 36 yards. That’s enough for over 30 antennas. I used the .56 size. WalMart has it too, apparently.

Maybe I missed where you have it, but what are the dimensions of your ground plane?

I uploaded all the instructions and templates to Outernet. Hopeful it will appear soon.

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