In urban areas, I've always found quite higher reception of man-made
noise on verticals, for what ever reason. And unless the vertical is
over an extended flat copper roof (block of same height row houses),
practically speaking there's 3 db gone at those touted low angles
right off the bat, to loss from ground absorption and clutter in most
situations.
And even IF verticals were better for 1000 miles and out, for those
who can only have a single 40m antenna for practical reasons, there
are a lot of QSO circumstances wanting a contact in a vertical's
pronounced skip zone.
Anecdotal material around here finds owners quite pleased with 40
rotatable dipoles. Now that I think of it, can't point to anyone who
took one down in favor of a vertical. Often find it installed off 90
degrees instead of a 40 2 element that was trashing 15 meters on a
co-mounted tribander.
And I simply do NOT agree with the 100 times better, or even just
better, except in extreme conditions when ONLY the very lowest angle
is coming in. I've never found a vertical to compete with a dipole at
height on 40. The single exception would be right at the edge of salt
water, but only in the directions over water.
On 160, and to some degree on 80, this reverses, as W8JI has proven
(has compared a 160 dipole at height (!!) with a properly
ground-screened full size vertical), but that is a different issue.
Something else not well understood going on.
Further, 70 feet or so up on 40 has very little high angle reception,
if that is what one wants to do.
Leave your vertical up when you put up your C4S (if that's what you
get). Let us know how it works out.
73, Guy.
----- Original Message -----
From: <i4jmy@iol.it>
To: <k2av@contesting.com>
Cc: <bruceosterberg@msn.com>; <Towertalk@contesting.com>
Sent: Monday, July 08, 2002 9:20 AM
Subject: Re: [Towertalk] F12 C4S
> Transmitting is not everything and a dipole has a low rejection of
> unwanted signals from high angles, it's F/S is quite objectionable
to
> be considered directivity at medium high elevations.
> If this were not enough I didn't find any gain by a dipole (half WL
> from ground or more) over a quarter wave vertical, on 40m, beyond
1000
> miles hops.
> Here in south europe, more than sometimes a vertical is quieter and
> reduces broadcasting signals so allowing more reception of NA
signals
> above 7.1 MHz.
> Surely, instead of an horizontal dipole I'd go for something with
> directivity, like a two element yagi or a set of switchable sloping
> dipoles/verticals.
> The extra gain over a simple dipole or a vertical will be the
marginal
> issue, while reception is hundred times better.
>
> 73,
> Mauri I4JMY
>
> > If you care about 40 meters, the C4S will walk all over the
vertical.
> > 52 is a wee bit low, but it is still high enough to outperform any
> > single vertical. BTW, the F12 linear loaded stuff is very
sensitive to
> > metallic guy wires in the vicinity. If this is a self-standing or
low
> > support crankup, you will do fine.
> >
> > 73, Guy.
> >
> >
> > ----- Original Message -----
> > From: "Bruce Osterberg" <bruceosterberg@msn.com>
> > To: <Towertalk@contesting.com>
> > Sent: Sunday, July 07, 2002 5:51 PM
> > Subject: [Towertalk] F12 C4S
> >
> >
> > >
> > > Good Afternoon:
> > >
> > > Well if you only had one tower and wanted a 4 band system would
you
> > go with
> > > this antenna if your tower could handle it? I would like to put
a
> > > tri-bander at 52 feet on a Crank up tower, and was thinking
about
> > one that
> > > had a 40 meter dipole as one of the elements.
> > >
> > > After Reading Steve Morris and H. Ward Silver, K7LXC, N0AX,
> > tribander report
> > > I know They likesd the C3, C4, combo. ( even though c4 was not
> > tested), but
> > > would I get any benefit on the 40 meter dipole, or should I
stick to
> > the
> > > elevated 1/4 wave vertical at 20 feet with eight sloping 1/4
wave
> > radials?
> > >
> > > If I did not get this antenna I would get the C31XR.
> > >
> > > 73 Bruce N9BX
>
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