John,
I wouldn't recommend elevated mounting of the Challenger DX. As I've stated
before, if you had one on hand, and lifted it off the ground, you'd know
pretty quickly why this isn't recommended. It's top heavy, catches a lot of
wind, and really needs a strong, substantial base, or the base will be the
weak link that renders the antenna scrap aluminum in the yard below.
However, just for clarification, the three 25' wires attached like radials
to the base of the Challenger are not a counterpoise. They are
bottom-loading to achieve resonance on 40/80 meters, and do nothing at all
on the higher bands. The Challenger is not a base-fed vertical, it's
center-fed, with linear loading on most bands as well as bottom loading on
40, and top and bottom loading on 80. I've disconnected the wires
completely and noted zero impact on 20-15-10m, but a rather dramatic impact
on 40/80 (like a resonance shift, completely out of the band).
WB2WIK/6
"If everything seems under control, you're just not going fast enough." -
Mario Andretti
> -----Original Message-----
> From: John von Gonten [SMTP:n5bsd@arrl.net]
> Sent: Sunday, October 06, 2002 1:59 PM
> To: towertalk@contesting.com
> Subject: [Towertalk] GAO Challenger DX
>
> I am looking at starting my station with a GAP Challenger DX Antennae.
> I will have to mount this at least 10ft off the ground to keep it out of
> harms way, too many accident prone people around here. :)
>
> Does anyone have suggestions on the performance and use of counterpoise
> when elevated for this antennae?? And how well do they work for DXing
> and contesting? I am trying to find more real world data on this, my
> budget and lot prevent me from getting to elaborate with my antennas
> currently.
>
> I have had a few people tel me they are strictly ground mount and even
> the GAP tech support people have no ideas on how the counterpoise would
> work in an elevated situation.
>
> Any and help will be greatly appreciated.
> --
> 73
>
> ------------------------------------------------------------------------
> | John von Gonten - N5BSD | ERROR 406: file corrupt:
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