A dish made out of aluminum foil

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Today I did not have anything special to do and so had some time. Because I happen to have a Satlook Micro available for testing, I thought for myself "let's try that urban myth": Will a simple aluminum foil, shaped with a ball, work as an emergency satellite dish?

I used the following material:

• Digidish 33cm with a Technisat LNB Single Universal
• Smart Titanium Edition Single Universal 0.2dB
• Satlook Micro
• one roll of aluminum foil as usually used in the kitchen
• a football

First trial: I covered about 30% of the football with two sheets of aluminum foil, in order to shape the foil.

I used the DigiDish to find the position of Astra 19.2E and then tried to obtain a signal above noise-level with the foil and the Smart-LNB. The result: nothing.

I spend a further hour or so and came to the conclusion, that half a sphere made out of aluminum foil won't work for sure.

The I tried to shape the foil using the DigiDish. With that I finally got some signal on the Satlook, but that was not enough to get a lock on a digital transponder.

Again, I spend an hour testing without success.

Then I had the idea of getting back to the roots and use an analog receiver!

Setup: Analog receiver, LNB connected directly to the receiver and a Casio Mini LCD TV.

Refreshed the shape of the foil on the DigiDish and pointed again to Astra.

Unbelievable: I got a picture!!!

After some further trials, it became obvious that it is indeed possible to build a satellite dish out of simple plain aluminum foil. To receive ZDF on Astra 19.2 I had used only a very rudimental shaped 30cm x 30cm piece of foil, which was full of wrinkles. Because the foil was very thin, it was difficult to maintain it's shape. Even so getting a picture was beyond my wildest dreams.

Interesting was the fact, that I laid the foil against the window (on the outside, of course) and when I slowly moved the LNB, I could receive ZDF again, even though the foil was not pointing in the right direction. This means that multifeed would be possible.

Conclusion:

• Aluminum foil will reflect the electromagnetic waves of satellite communications.
• Due to the relatively big wavelength, the foil does not need to be smooth.
• It is possible to receive Astra 19.2E with almost anything...
• It was a fun afternoon!

If you want to build an aluminum dish yourself, you only need to do this (I actually refined the technique):

• fold the foil into two layers for increased thickness and robustness
• fold the borders of the foil for even more robustness
• and now the ultimate trick: place the foil on some carpet and roll a ball (must have a smooth surface) over that foil a few times, in a spiral from the inside to the outside
• you will get a foil with a parabolic shape

Lean this foil onto something with the same elevation as you would use a regular dish and search Astra!

It will work for sure.

It is interesting to see, with how much power modern satellites are actually broadcasting.

I have used an analog receiver, because I did not have a spectrum analyzer. The Satlook Micro is a nice equipment for regular dish alignment, but was not an ideal tool for this experiment. I did mount a support with my daughter's Lego pieces and managed to get digital transponders, as well.

Here are a few pictures: