> For example, did you know that if you use an elevated resonant
counterpoise the radials all radiate substantial
> signal in the nearfield area? Did you know the more radials you use the
less problem that is? Or did you think
> that with a "balanced layout" the radials don't radiate?
I want the radials to radiate. I kinda liken each element as a half wave
dipole with one end of the dipole in the form of a big fan. The worst I can
say about what I am doing is that I always have felt that I hear better than
I transmit - but then one morning when I had my 80m cq beacon running I was
spotted in Hungary with the comment 'no ears'. Oops.
> Knowing the radials all act like antennas can help us plan a system
better. I'd never install other feedlines or
> antennas parallel and close to a system using a few radials, knowing that.
I'd never bring a radial near a
> telephone line or TV antenna feedline. If I thought the radials was
"perfect", I might make a mistake and do that.
I am fortunate in that both of my 4 squares are in the clear. The radials
and feed points are above surrounding objects. No tall trees in the Arizona
desert to worry about.
> Did you know that you lose field strength with elevated systems if you
don't use a choke or current balun to
> isolate the system from earth? I don't see many people isolate feedlines
from the feedpoint of small radial
> systems, yet it can be as much as a dB or so change!
Somehow I confused the feed lines (plural) statement with the impedance
transformer/phasing lines that feed each element. I do have current baluns
at the feed point to the Comtek phasing boxes, which does as you say.
> Like the comments before none of this says "don't use them".
> It just points out the quirks of using a sparse radial system of any type
and things you have to watch for.
> If you look at:
> http://www.w8ji.com/verticals_and_baluns.htm and
> you'll see how important it is to isolate feedlines even on groundplanes
with four radials.
I use baluns on all of my antennas - just because. I think the balun gives
me a more symetrical radiation pattern.
> I hear people constantly saying with four radials 1/4 wave or higher off
the ground the radials are "perfect", and
> I've even heard people say "two radials are actually enough, they only
used four on a groundplane because it looks
> Some antennas are even sold using end-fed radiators without any radials!
I like the comment "My antenna is flat across the band." My four dummy
loads are also flat across the band. And then there is the "I can work
everything I can hear". But can you hear everything that can hear you?
Note my previous comment re the Hungarian station?
> At some point someone has to learn how the stuff really works in order to
make good decisions, even if they are
> decisions on where and how to compromise.
There is something we learn with modelling software - all antennas are
compromises. Makes me a strong advocate of rolling my own so I can control
where the compromises are made. Many times I have had friends of mine look
at my antennas and make the comment "I would rather purchase a commercially
made antenna that works". I love it.
> 73 Tom
de Paul, W8AEF
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