Hi Guy
Thanks for your detailed reply. I am building a two-phase vertical for 80
meters, 1/4wave separated. Untill now I usee 1 single vertical with around
50 or 60 radials and I have noticed that towards East the dipole works way
better than the Vertical (maybe because towards NA I have a down slope
cliff untill the ocean and towards EU/AS I have about 100m high montain).
I got several replies dead it's not worth the effort to put the two dipoles
phased, so I guesd I will skip it and try to compare the 2 elem vert with
dipole towards EU/AS
Thanks to everyone for the suggestions.
73s Filipe Lopes CT1ILT aka CR6K
Sent from my Huawei Mate 8
Em 10/10/2016 10:38 p.m., "Guy Olinger K2AV" <k2av.guy@gmail.com> escreveu:
> If that were not enough, W8JI famously had a 160 dipole up 270 feet doing
> A/B tests vs. his verticals, this for over a year I think. In the end, he
> heard better signals on the dipole just a handful of times. Most of the
> time the verticals were significantly better.
>
> 160 is on the vertical polarization side of a dotted line somewhere between
> 160 and 80 meters where there is some poorly defined and poorly understood
> modal shift, heavily favoring vertical for non-NVIS paths on 160.
>
> For some, an inverted vee is a possibility where other physical
> configurations are just not possible. If that is what you can do, it sure
> beats not being on the band :>)
>
> Phasing two of them will get you 2-3 db over just one of them. But probably
> the two will get beaten by an *efficient* inverted L over an *efficient*
> counterpoise, because the L will smoke any inverted vee at low angles, and
> is on the correct side of whatever the modal shift is.
>
> The emphasized "efficient" modifier twice in the last sentence is very much
> intentional.
>
> On 160 it is very easy to lose energy to induced current in the ground, or
> miscellaneous dielectric loss. If your reason for choosing an inverted vee
> is not because of physical site restraints, then it is very likely that
> prior vertical attempts were diminished, possibly severely diminished, by
> losses avoidable with various techniques.
>
> The big loss advantage of an inverted vee is that 1) there is no lossy
> counterpoise and 2) the RF current max is way in the air. There are ways to
> invoke those advantages with vertically polarized antennas. An inverted L
> out in the clear over an FCP is a good one, but only one over some several
> vertical alternatives.
>
> 73, Guy K2AV
>
> On Mon, Oct 10, 2016 at 9:25 AM, Herbert Schoenbohm <
> herbert.schoenbohm@gmail.com> wrote:
>
> > Probably not worth the effort as any dipoles less than 250 feet high are
> > serious cloud warmers.
> >
> >
> >
> > On 10/10/2016 9:21 AM, Filipe Lopes wrote:
> >
> >> Hi guys
> >>
> >> We are rebuilding our station and I was thinking about putting up 2
> >> dipoles
> >> 1/8 wavelength apart.
> >>
> >> Has anyone ever tried to phase them for example with Christman method?
> >>
> >> Thanks
> >> Filipe Lopes CT1ILT aka CR6K
> >>
> >> Sent from my Huawei Mate 8
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