Hi All,
I guarantee the 20m and 15m driven elements touch on a C31RX-H.
I was getting big jumps in swr on both the bands with just one insulator per
side in the OEM stated position. The only solution was to add two more
insulators near the tips of the 15m driver. The swr problem was occurring at
wind speeds of 50-60mph so if you get those speeds and expect to be able to
use your C31 ask for and fit two insulators per side.
73 Clive GM3POI
----- Original Message -----
From: "Pete Smith" <n4zr@contesting.com>
To: <towertalk@contesting.com>
Sent: Tuesday, May 15, 2001 5:01 PM
Subject: Re: [TowerTalk] Force 12 C3 spacers
> At 09:52 AM 5/15/01 -0400, Jerry Keller wrote:
> >This is not the first report of some F12 antennas needing spacers to
avoid
> >wind-whipping problems. I've heard of this before, from a fellow who took
> >his down. He reportedly asked F12 about this, was told they haven't had a
> >problem, but then was sent some spacers to alleviate the problem. The
> >conclusion he drew was that if the F12 had no problems with this, how
come
> >they had spacers on hand to resolve the problem? I hadn't thought much
about
> >this with only the one report, but now there's several....I had been
> >considering this antenna up until now. I am following this thread with
great
> >interest.
>
> Jerry, I have 2 C-3Es, at 22 and 30 meters above ground, in a wind
> environment similar to yours, I suspect. Peak wind at this QTH so far has
> been around 75 mph in gusts. The elements in the driven cell, like all
> the elements, "surf" a lot in the wind, but I have never seen anything
that
> suggested they were touching. At most, what I see is some SWR fluctuation
> when operating on 15 -- but it is small, perhaps .1-.2 at most.
>
> Could it be that Force 12 produced the spacers to meet the desires of
> users, rather than because they believed there really was a problem?
>
> 73, Pete N4ZR
> Contesting is!
>
>
>
>
>
> List Sponsor: Champion Radio Products - We'll be at the Dayton Hamvention
> with all of our safety equipment and other products. Stop by booth #559
and
> say hi.
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>
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List Sponsor: Champion Radio Products - We'll be at the Dayton Hamvention
with all of our safety equipment and other products. Stop by booth #559 and
say hi.
<A HREF="http://www.championradio.com";>www.ChampionRadio.com</A>
-----
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