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O'Reilly's Antenna Shootout
nickynicky9doors writes: "From Rob Flickenger O'Reilly Network's Systems Administrator :
'Gregory Rehm hosted an Antenna Battle Royale between a Lucent popsicle stick, a couple of Pringles Cans, our Coffee Can, a Hunt's Tomato Sauce can, and a 40oz can of 'Big Chunk' beef stew. Who was the winner?'" Let's just say it doesn't come loaded with saddle-shaped styro-chips.
the lucent popsicle is nothing more than a 5/8ths wave antenna.. signals not at the horizon will suffer (up.down)
The pringles can is nothing more than a basic beam.. 1 driven element and 1 reflector (the metal bottom) it is not acting like a waveguide because the "metallic substance" is not electrically conductive (in my tests... if people in other parts of the country would test theirs? it would be interesting.)
The metal cans are a type of waveguide... more of a feedhorn design.. they would be awesome pointing at the focal of a dish. if you were to put a 45Deg cone around the opening you would further increase the gain of the can.
The best thing to do is modify a existing 2.4ghz feedhorn or antenna. you'll find them on Primestar dishes and KU band old sattelite dishes. they need a bit of tweaking (filing on the stub) but work best and the little aluminum concentrator on the old sattelite dish types ( the set of concentric rings around the feedhorn opening) will give another 2-3db not in gain but in selectivity and rejection of off axis signals. (better noise floor)
Do not look at laser with remaining good eye.
Second, people have done the Primestar dish thing before and report 22db gain with it, not 30-50.
Third, according to the ARRL antenna handbook, the 200" optical receiving antenna known as "Mt. Palomar" has 148db gain. Frankly, I don't think anyone's satellite dish compares to this (or could, at microwave frequencies)
Remember, 100db gain means 10 million watts of effective radiated power for every milliwatt of input power.
Antennas with over 30db of gain simply are not that common.