I recently A/B'ed two 40m antennas that were
very similar to your existing and proposed
antennas. One was an inverted vee at 60
feet (apex height) with a 90 degree apex
angle, and the other was an inverted vee
at 30 feet (apex height) with a 120 degree
apex angle. On "DX" signals (basically
more than 1000 miles away), the two dipoles
were interchangeable to within the resolution
of flipping a switch back and forth and
looking at received signal strength on the
S-meter. For close in signals, the 30 foot
high antenna was 3 to 6 dB better because of
the NVIS mode. I also A/B'ed a ground mounted
vertical to these vee's and found that it
was equal to them or slightly better on DX,
but was a total dog for stuff within a few
hundred miles since it has a null at high
angles (no surprise).
Rick Karlquist N6RK
richard@karlquist.com
www.n6rk.com
www.karlquist.com
> -----Original Message-----
> From: towertalk-admin@contesting.com
> [mailto:towertalk-admin@contesting.com]On Behalf Of Robert Webb
> Sent: Friday, June 21, 2002 11:03 AM
> To: towertalk@contesting.com
> Subject: [Towertalk] 40M Dipole Height.
>
>
> Hello everyone, a quickie for you. I have a 60ft tower with
> a 1/4 wave 40m
> coax fed dipole attached at the 55ft point. Due to land
> restrictions, the
> two ends slope down sharply and the two ends are appx 40ft
> apart at their
> lowest point. Would my radiated signal improve if i
> lowered the feedpont,
> therefore increasing the angle of the slope or is it better
> to keep the
> feedpoint as high as possible. I just cannot work out or
> see in my mind
> which would be the best option. Hope it all makes sense,
> and thanks for
> youre time 73s
> Robert Webb
> G0URR
>
>
>
>
>
>
>
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