Quote:
Originally Posted by Tim58hsv
I doubt it would be any better than one of those single bow tie antennas that you snap onto a tv's rabbit ears. The only advantage to the shoe box design would be the reflector but I suspect the single bow tie would still be better.
Either way, it seems like a lot of work for such little pay off.
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Well he is trying to show I think it's really that simple to make an antenna. There are flaws in his design if you want to look at it that way, but I didn't take that as his point.
If you want his design picked apart, first he didn't measure the two halves of the dipoles. So some duplicating has to rely on having the same size box.
Next a dipole is close to 75 ohms, not exact but close enough for a receive antenna, but worse is a simple dipole is a balance antenna and rg6 is unbalanced feed line. This causes currents on the shield of the coax, that then act as an antenna, adding or subtracting from the signal received by the dipole. In a nutshell you can more the coax around and change the signal if it's weak, and no feed line should do that.
Third, just like the element lengths, the distance to the reflector will greatly affect the antenna pattern, gain on given channel.
All that negative stuff said, I bet with the reflector making it more directional, for some people it will give better signal quality than their bowtie or loop.
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Improvements?
Put a bow tie or look in place of the dipole, as they are 300 ohm unbalanced and can be feed into coax via a common TV balun.
Guess what if you put a loop in front of it? You basically have a ClearStream1. So why do they cost so much? Need I explain marketing scams?
Another thing would be to make a folded dipole and put it in front of the reflector.
I think for off the shelf stuff, a Radio Shack bowtie, with the balun attached as close as possible would work best. What the best reflector difference would be, I don't know.
But it shows how simple antennas can be, even if they are not perfect.
DIY Shoe Box Antenna?
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