You could be forgiven
for being skeptical of an antenna like the Antennas Directv Clearstream 2
. After all, it doesn't look like any other antenna you've ever seen before. Yeah, there's a metal grid in the back, but the front is... black plastic. Everyone knows plastic can't be used for an antenna, right? And what is that black plastic "8" thing on the front anyway?
The secret is simple. The "8" thing is the antenna, but its metal bits are encased in a sexy plastic enclosure that's completely transparent to radio waves. The back part, the grid if you will, is called a "reflector" and it makes the antenna work twice as well by bouncing the signal to the back of the antenna so both front and back surfaces work together. It doesn't have to be solid because of a special quality of radio waves... they can't pass through holes of a certain size. If you know what size that is (and specific frequencies are tied to different sizes) then you don't need to waste a lot of material. That makes antennas like the Clearstream 2 light and effective.
A design like this, with a reflector and an x-shaped, 8-shaped, or bowtie-shaped item in front, is very effective for UHF frequencies. (Most stations broadcast on UHF, but some still use VHF. If you need to pick up VHF frequencies, you'll need a different type of antenna.) There are many different designs but the basic idea is the same.