[Antennas] Fluid Motion Antennas

2002年6月27日 11:09:56 -0700

I read somewhere (maybe Fluid Motion's web page) that the element
spacing was not critical on these antennas because it can be overcome
by the fact that the elements are always the proper length no matter
what the frequency. The article went on to say that it WAS critical
on multiband trapped beams because there was no one good spacing for
the elements that was good for all bands but what do I know? If the
specs that are quoted are accurate, I would say that the performance
will be pretty good. I currently have a 27 year old TH3-MK3 and I am
seriously considering replacing it with the 2 element SteppIR but 800ドル
is a lot of money for a 2-element beam so I am having a difficult time
making up my mind. Besides the specs, they have some nice features
especially having the controller interfaced to the rig so that it
automatically tunes as the VFO is changed. I would be using it on a
IC-756PRO and a Elecraft K2 but I am not sure if the controller
supports the K2. Thank you for your thoughts and would really like to
hear from anyone who has tried the 2-element beam.
John
K7SVV
K2 #2569
----- Original Message -----
From: <[email protected]>
To: <[email protected]>; <[email protected]>
Sent: Thursday, June 27, 2002 10:28 AM
Subject: Re: [Antennas] Fluid Motion Antennas
> I think George is totally correct.
>> The antenna design is interesting and we hope you'll keep us
informed on how
> it works out.
>> One comment, there was a chap (a W6-??) back in the 1960's that did
something
> similar with his own design. He varied the element lengths all over
the place
> and as long as the directors were shorter and the reflector was
longer than
> the DE, it was pretty hard to screw the gain up to any degree. The F
to B and
> bandwidth / SWR varied quite a bit of course. But the one thing that
really
> changed the gain significantly was just adding more boom length.
I've done
> the same thing with a FS meter and confirmed his results with
changing fixed
> tuned elements. But adding more boom made all the difference.
>> It would interesting too if the Fluid Motion antenna had a way
(probably
> beyond the cost limits) to vary element spacing as well as element
length.
> From what I know of the antenna, you have 3 elements spaced out on a
boom
> with no way to move them closer together or farther apart to
optimize the
> bands (20M-6M) it covers. If it did, you could then you could really
change
> all the parameters.
>> Brian
> - - -
>> Your moderator for this list is:
> Larry Wilson KE1HZ [email protected]
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