I've seen 2 M J-pole antennas mounted "upside down" on a offset mount
near the top of a tower. Since the J-pole is essentially a 1/2 wave
vertical, end fed, the radiation would be the same in either
orientation providing there was no radiation from the feedline. The
J-pole is easy to construct, have made several over the years.
73, Stew...
>
>
> Jonathan,
>
> If memory serves me correctly, some of the higher end commercial
antenna
> manufacturers state that the vertical radiation pattern is designed
for a
> specific orientation of the antenna. Inverting the antenna may
cause a
> downward tilt of this pattern, lowering the angle of radiation below
the
> horizon, which may limit your range. However, this probably
wouldn't matter
> much at your typical amateur tower height, but something you may
want to
> look into just for grins.
>
> 73 de Bill, K9RZ
>
>
> -----Original Message-----
> From: Jonathan Kaplan <jonk@jskent.com>
> To: Towertalk@contesting.com <Towertalk@contesting.com>
To: <towertalk@contesting.com>
> Date: Wednesday, February 24, 1999 10:52 AM
> Subject: [TowerTalk] Verticals upside down on a tower?
>
>
> >
> >In planning a tower for my site, The idea came up to mount
> >my 2m verticals on side mounts. The question I have is when
> >I do mount a vertical on the tower, can I mount the antenna
> >upside down so that it hangs down from the side mount instead
> >sitting on top of the mount? That way I could avoid having a 2m
> >vertical interfere with rotation of HF antennas above it. FYI, the
> >tower is a USTower HDX-555.
> >
> >Thanks & 73
> >Jonathan KO6XS
> >
> >
> >
> >--
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> >
> >
>
>
> --
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>
>
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