So, I was annoyed that my Yagi antenna was enclosed in a plastic-tube, which lets it roll around and fall off the table occasionally, but without its enclosure the elements hooked in anywhere. So I wondered, since the material (I assume it's PVC) is radio-transparent anyways: Couldn't the antenna be enclosed in other shapes as well - as long as they are radio-transparent?
Note: The antenna I'm talking about is just a simple 19 Element (17 Directors) Yagi antenna for 2.442 GHz home Wi-Fi.
Basically my questions are:
- Is it ok to completely enclose the elements themselves - or do they have to have air (or any free space) around them?
- Is the boom required to be at the center?
- Does the boom actually have any effect when it's radio-transparent and non-conductive anyways?
- Would it affect the Antennas performance, if there were two (non conductive) booms, holding the elements with their edges?
I just wondered about this, because I remembered my physics teacher telling us (decades ago), when frequencies are involved, things vibrate/oscillate. A tight enclosure might hinder this eventually.
I have drawn (sorry for my rather poor paint-skills) two designs, which I would like to try out.
This first design would enclose all elements in pockets, to prevent them from moving and possibly even corrosion if it's airtight.
This ladder-type design was just an idea to save some PLA material first, with just the benefits of saving space and preventing the elements from hooking in anywhere.
I know one could probably simply slide the original Yagi inside some sort of flat plastic sleeve - keeping its boom, and keeping the elements "free". But such projects simply trigger me ^^ - and the antenna that I bought is manufactured rather... "creative"... so I'd like to rebuild this whole thing anyways.