An efficient dipole, placed at a minimum of 1/2 Wl from ground can have
some transmitting gain on 40m when compared to a single element
efficient vertical, may be...
The calssical inverted V dipole or a dipole that's significantly below
the half WL from ground is surely not so efficient, and by several dBs
if compared to either the previous antennas.
Some actual test we made placing an High Gain dipole on the top of a
23m tower showed practically no gain for the dipole compared to a
system of 4 vertical sloping wire dipoles (rad + 3 parasitic ref).
The sloping system instead beaten all the times the h-dipole for
reception and rejection of unwanted high angle signals where the dipole
always showed to be really a pain in the neck, wherever you turn it.
I did also a comparison with a full size 40m horizontal dipole, abt.
1/2 WL from ground, and a full size 40m GP with 36 radials, roof
mounted (quarterwave from ground) and found no differences (when not a
gain for the GP).
At least in my opinion, I think some people is often too easily
assuming datas by deduction and gives too much importance to
transmission where it should be given some care to the "two way"
perspective.
Finally, I stay on my own that having chance to reach half WL from
ground is a big waste to use dipole and not an antenna with directivity
and secondary that on 40m I often received into a vertical a DX that
was instead masked by QRM in the dipole.
73,
Mauri I4JMY
> > A practical dipole has a clear transmitting advantage on 40 in most
> > cases, while a practical Inverted L or vertical has the clear
> > transmitting advantage on *40 meters and high...*in most cases.
>
>
> Weird. It should have said
>
> A practical dipole has a clear transmitting advantage on 40 in most
> cases because it is easy to make high in terms of the operating
> wavelength, while a practical Inverted L or vertical has the clear
> transmitting advantage on 80 and 160 meters, where a dipole is
> unlikely to be high enough to have a useful low angle field strength.
>
> Also it should have added a comment about N6RK, who I believe has
> made some twenty meter over-the-air comparisons between verticals and
> dipoles. Rick?
>
> 73, Tom W8JI
> W8JI@contesting.com
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