All this field day antenna talk has me wondering... In multi setups, I know
distance helps, but is it true that keeping the antenna parallel also helps?
We are considering going from three stations this year to 4 so that is going to
complicate our antenna setup. We typically have run two band fan dipoles.
Sent from my iPhone
> On Apr 14, 2015, at 2:38 PM, Rick - DJ0IP / NJ0IP <Rick@DJ0IP.de> wrote:
>
> Ralph,
>
> I really liked your post.
> I don't quite follow your bit about being against 450 Ohm feedline but the
> rest of your post was indeed impressive. Maybe you know something I don't
> know..
>
> Long low band antennas, used on the high bands, regardless of how good the
> SWR looks, are a waste. Less is better. A short dipole with maximum 6m (19
> ft.) per side is the longest the dipole should be. Otherwise the two major
> lobes will break up into several smaller lobes with multiple peaks and
> nulls. Not good.
>
> 20 ft. per side is borderline. I'm not sure. I would make it just 19 ft.
> per side to be on the safe side.
>
> I don't have a lot of experience with FD in USA. I have won outright, FD in
> Europe several times.
>
> Here in Europe, one of the best FD antennas one can have is a lazy loop (for
> 80m).
> This is basically a horizontal loop, 84 meters (21 meters per side), mounted
> about 30 to 40 ft. high. It is fed with 300 or 450 Ohm openwire and matched
> with a Johnson Viking matchbox (or Annecke). It may also be matched with
> other solutions.
>
> Ralph's statement about using an "L" or "T" matchbox is correct, though
> using a "Symmetrical L" such as Palstars BT-1500 or a "Symmetrical T" such
> as MFJ's MFJ-976 do work very good. The Link-Coupling of the JV Matchbox
> (or the Annecke, it's German successor) gives you about 20dB more of common
> mode impedance which is a great benefit. It is often quieter than the other
> technologies.
>
> There are some ways of using lesser matchboxes but for now I support what
> Ralph said.
>
> Categorically rejecting an OCFD is like shooting yourself in the foot.
> I would suggest you aren't up to date on the latest OCFD technology.
> Your information you have is probably sound, based on what we knew 15 years
> ago, but simply no longer true. (Not you Ralph, that bit was for the
> original OM that started the thread).
>
> Ralph's post was super.
>
> 73 - Rick, DJ0IP
> (Nr. Frankfurt am Main)
>
>
> -----Original Message-----
> From: TenTec [mailto:tentec-bounces@contesting.com] On Behalf Of Ralph
> Matheny K8RYU
> Sent: Tuesday, April 14, 2015 6:08 PM
> To: Discussion of Ten-Tec Equipment
> Subject: Re: [TenTec] Field day antennas
>
>
>
> In my experience the 80M antenna on the higher bands will be a dud. If you
> must, use a loop rather than an dipole, and feed the loop with 300 (NOT 450)
> line via a true balanced link-coupled tuner, like the Johnson Matchbox of
> 60's fame. Both 80M antennas have just too many nulls on the higher bands.
> T or L network tuners with "baluns"
> at the input or output have not impressed me in this service, but that may
> be a personal prejudice.
>
> I think a short dipole for the higher bands is worth the trouble, say about
> 20 feet on a side, again with 300 ohm feed line.
>
> I stay away from the 450 stuff because one can end up with some VERY low or
> high Z at the tuner, and since the bands are harmonic related if it's good
> on one it will be bad on another to a much greater extent. If I could get
> 150 ohm open wire, I'd use it!
>
> One man's opinion.
>
> de K8RYU
>
>
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