If any of you know how to simulate patch antennas on EzNEC could you drop me a note I can run simulations.
-Cecil
brilliant!!
And now, the next installment of, âWhat Can I make From Cardboard And Foil?â
And tape, and a premade pigtail with SMA adapter, I had lying aroundâŚ
No foam separator. Just cardboard.
And, a twist⌠This one was fabricated using information from the internet. No actual physical measurements of the subject model. I know from the Internet that the antenna is 12cm side, and that the spacing between elements is 7mm. There is a photo out there that shows the antenna with a ruler next to it.
So, using that picture and Paint.net ruler function, was able to surmise that the center element is about 85mm, and the parasitic is about 80mm. I went with that.
Here it isâŚ
âdrivenâ element and parasitic
finished product
and the performance just sitting in the windowsill:
Not super impressive, but proves that it is possible to make a useable Outernet antenna with a 12cm square stack of cardboard and foil and some sort of feedline.
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That is absolutely fantastic @k5ted !!!
see revised results. It is not spectacular, but it is just looking out a window, not particularly aimed well.
This is bananas!
quad being put together as we speak
Sorry, quad paper helix
Geez I am enjoying this!! The cardboard & foil patch is just crazy!!
I love the âsuck it & seeâ attitude that you have @k5ted 
Good Onya
Many centuries ago when I was playing ATV on 70cm I kept coming up with weird ideas for antennas ( and other things) but when I mentioned it the the experts in the club, they would tell me why it wouldnât work, often with a nice physics lesson thrown in for freeâŚ
Once I decided to just make the bloody things anyway, and realised that sometimes things work & sometimes they donât, my life became much mire interesting
So by all means do the maths, but I have built Antennas that should not work, but do anyway.
Keep up the âhackerâ spirit there Ted!
Everyone knew itâs impossible! Then came a man who didnât know this and made it happen!
Keep up the HAM spirit! 
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ATV⌠That was fun. I still have a PC Electronics transmitter and Mirage N26 amplifier in a box somewhere. Have thought about firing up the old analog system as a UHF video beacon though.
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@k5ted
In Australia it was originally 426Mlz
I had so much fun with the old ATV⌠we even took a transmitter up in a light aircraft to get a distance record
I built a transmitter in a matchbox (well it needed a PA , but it was still a transmitter!!) That would have been about 1981-82
LOL!
you guys must read this than:
http://www.rtl-sdr.com/transmitting-datv-with-a-raspberry-pi/
(proper filter not made yetâŚso far from EMC compliantâŚ)
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very cool indeed @zoltan : )
I have not played with any digital ATV at all⌠Maybe I should have a play!
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Thatâs s cool! Last time I was on ATV was using a 7038 vidicon that had been burned in on on a bank security camera so all my video showed the bank vault lightsđ
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It was always a bit of fun to see what was burnt into second hand vidicom tubes
Helical Update TimeâŚ
I picked up something on the web about using parasitics on the helical. A few variations on the theme, most interestingly this idea of close spacing the parasitic.
So, I tried it by doing a mashup of my two helical designs⌠This is the original cardboard, foil, and wire helical with an added parasitic of just the tube and tape from the paper helical design.
Using it for SafetyNet and Aero. The addition of the parasitic brought the indoor signal up considerably, 2dB or more, which was what it took to get reliable STD-C NCS decoding.
Note that the elements are lined up, not spaced apart. The parasitic wind starts 1.5 turns up from the feedpoint and stops a half turn after the driven wire element. Here it is in position receiving Inmarsat in the corner of my shack
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very cool! 
is there any theory how the parasitic help to get better SNR?