I have never used EZNEC. I put up the most aluminum I can as high as I can
afford and work everything I can hear. I do believe in lots of radials for
verticals and ran some of mine down into the near by lake.
I put up all I can and dont worry about fine details like if it is 5 or 7
degrees. It is nice folks make all these plans, but ............
73, Charly
On Fri, Aug 14, 2015 at 11:35 PM, alannottage--- via CQ-Contest <
cq-contest@contesting.com> wrote:
>
>
>
>
> I don't have a scientific calculator to hand Mike, but those '200 ft hills
> are what 18 degs? 100' is 9degs? The latter is going to be fine for EU on
> the high bands in good times, but if you're really talking verts on the
> beach, then that whole saltwater scenario is what is going to count. The
> Fresnel zone will be out to 10 wavelengths at least so 1000 feet is going
> to be fine down to 30 metres (10Mhz). On 40m, that's likely to be a little
> less than ideal, but the improved ground conductivity in the very near
> field will likely begin to play into your hands at that frequency and in
> particular below as Ed says. Some of those places in VE1 that you describe
> are up creeks and might be just brackish rather than pure seawater at the
> 'beach' of course. Good luck!
>
>
> Al G0XBV
>
>
>
> -----Original Message-----
> From: Jim Brown <k9yc@audiosystemsgroup.com>
> To: cq-contest <cq-contest@contesting.com>
> Sent: Thu, 13 Aug 2015 18:09
> Subject: Re: [CQ-Contest] Verticals on the beach (AGAIN)
>
>
> The best place to study this is in the early chapters of the ON4UN book,
> where
> he talks about situations like this.
>
> Someone suggested HFTA. HFTA applies
> ONLY to horizontally polarized
> antennas.
>
> David is right -- NEC does allow
> two ground models. It would be tricky
> though -- the key here is the sea water
> ending in the range of 1,000 ft.
> So the model would have to start with sea
> water out to 1,000 ft, then
> shift to land for the second media. That would
> yield an overly
> optimistic view of ground losses, but would take the limited
> sea water
> into account.
>
> 73, Jim K9YC
>
> On Wed,8/12/2015 7:33 PM, David
> Gilbert wrote:
> >
> >
> > I don't remember for sure off the top of my head, but I
> think that
> > EZNEC+ has the capability of specifying two different areas of
> ground
> > conductivity surrounding the antenna. You could rather easily see
> the
> > impact of the nearby salt water if I'm correct.
> >
> > Dave
> AB7E
> >
> >
> >
> > On 8/12/2015 1:19 PM, Mike Smith VE9AA wrote:
> >> As we
> continue to look for land around the Maritimes for a small weekend
> >> cottage
> we occasionally come upon a location that has shorefront on
> >> saltwater, which
> really is not completely open water all the way to
> >> EU or
> >> USA, so it's
> not ideal. The south coasts of VO1, VY2, VE9 and VE1
> >> all kinda
> >> point
> S/SE
> >>
> >>
> >> I have found a couple with a clear shot to the Caribbean or
> Africa,
> >> but with
> >> so few contest stations there, it's really not very
> important, except
> >> perhaps for that rare LP to JA...
> >>
> >>
> >> A few spots
> have open salt water towards EU of around 1000', before
> >> it hits
> >> land
> again (opposite side of the harbour) then gently sloping up past
> >> that.
> >>
> (0-100/200 feet)
> >>
> >>
> >> So my question is really, does 1000' of salt water
> make any
> >> difference at
> >> all, or not enough to make any difference and
> the 200' hills on the
> >> other
> >> side of the harbour would be more hindrance
> than the salt water would be
> >> helping?
> >>
> >>
> >> There must be stations all
> over the world with a short salt water
> >> takeoff
> >> who could
> comment?
> >>
> >>
> >> Has anyone done any A/B comparisons or proof at
> all?
> >>
> >>
> >> I have read N6LF's and K2KW's and most related stuff on the
> Internet,
> >> but it
> >> generally references DXpeditions in the Pacific or
> Caribbean with
> >> completely
> >> open water as far as the eye can see. I am
> just wanting to know about a
> >> 1000' salt water runway, then low land
> again.
> >>
> >>
> >> Thanks,
> >>
> >>
> >> Mike
> VE9AA/VE1TTT/VO1TTT/VO2DX
> >>
> >>
> >> Mike, Coreen & Corey
> >>
> >> Keswick
> Ridge, NB
> >>
> >>
> >> _______________________________________________
> >>
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> >> CQ-Contest@contesting.com
> >>
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> >>
> >
> >
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> >
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> >
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--
Charly, HS0ZCW
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