On Wed, Aug 1, 2012 at 9:10 AM, Tom W8JI <w8ji@w8ji.com> wrote:
> I think the first step is explaining and verifying how a conductor can be a
> counterpoise without having external fields.
This is a non-issue, Tom.
It stems from what I meant when I said "cancel fields".
Apparently some considerable number, even the majority, think this
phrase means cancel fields entirely. To others this means
cancellation is taking place at some level. The latter has until now
been my usage of the phrase. I come by it honestly because I have had
many conversations using it this way without confusion or requests for
clarification. I can however think of an email exchange in recent
months where that may have been the crux, but I did not figure that
out at the time. I figured it out after all of yesterday's complaints
about how that can't be a counterpoise. And I see how it would radiate
into the discourse.
But I have no emotional need to defend it, nor have I any interest in
engaging in a linguistic debate which might be as juicy and fun to
linguists, as a good chess game is to others. Nor have I any interest
in "converting" anyone to one side or another. I will happily adjust
my usage.
** I sincerely apologize to anyone whom I may have misled by my terminology. **
>From now on, I will use adjectives and adverbs to qualify "cancel" in
the future, something that would be understood by someone of either
usage. I have no dog in any fight about which is right. Just another
example of the impreciseness of language and the demonic difficulty of
writing technical text that explains everything to everybody. So from
now on you will see:
a) "completely cancel" meaning 100% or close enough to cancellation
that it makes more sense to consider it cancelled than not.
b) "partially cancel" meaning some degree of cancellation, and
probably that what isn't cancelled requires reckoning.
c) "cancel to the degree possible", or "cancel to a high degree" where
partially cancel does not communicate the gist of it.
If one looks at the body of my comment (multiple posts over a period)
you will find many posts where I describe the outcome of the FCP,
footprint-wise, current-wise and field-wise, as corresponding to a
pair of opposing 1/16 wave raised radials, except with a useable feed
Z. This clearly has some radiation. It clearly is creating a field
beneath, and therefore inducing current in the dirt.
The FCP radiates at -30 dBi according to NEC4. That's really low for
an antenna element. But, it DOES radiate.
According to NEC4, using area integration of field squared data from
the counterpoises only, excluding the vertical radiator, the FCP only
has 8.2% of the power loss in the dirt as a pair of 1/4 wave raised
radials. But it IS a field and current, therefore power loss. The
graphical representation of this difference is graphed in figure 2,
page 22 of the article:
http://www.w0uce.net/Olinger_FCP_article_as_published_in_NCJ.pdf
The article was written last February and March.
Colloquially, "doesn't radiate" is how you would characterize a dipole
that came in at -30 dBi. Of course in other situations, -30 dB means
the thing is broken because you are looking for -100 dB. So I will try
to absent my discourse here of colloquialisms, but that is starting to
take the fun out of it. I would ask people to remember that my time
and effort on these issues is part of my hobby, and I am trying to
have some fun too. I am not submitting work to the PhD committee.
73, Guy
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UR RST IS ... ... ..9 QSB QSB - hw? BK
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