Quote:
Originally Posted by MartaJobs
Actually there is a common misconception with respect to RF and/or DC grounding, and its relationship to a ground plane.
The best way to think about vehicle ground planes is simply this; it is the metal mass under that antenna that counts, not what's along side. The second part is, the more metal mass the better.
Also you can make contacts with the lossiest of antennas, as any Outbacker or ATAS owner can attest to. However, if you want consistent communications, then you need a decent amount of metal mass under the antenna.
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Interesting idea, but no. The mass doesn't matter at all. What matters is the
surface area of the metal under the antenna.
Not even that, really; it is the effective reflecting area (and its location) that matters. There can be holes in it, for example, which would reduce the actual surface area; but if the holes are small compared to the wavelength of the signal we're interested in, they won't reduce the effective reflecting area. That's why a copper screen is as good as a copper sheet.
Either the screen or the sheet can be ever so thin, though, as long as it's thick enough so that the surface resistivity is limited primarily by
skin effect, which is pretty thin (thousandths of an inch) at HF.
Hardware cloth -- even chicken wire -- works pretty well, too, but isn't massive at all. The mass of metal is totally irrelevant.