Hi Bob!
Earlier this year I took two new XM-240s and converted them to the W6NL
Moxon design. They are installed at 185 ft and 120 feet on TIC Ring Rotors
and can be fed alone, both in phase or both out of phase. They replaced a
CushCraft 402CD at 140 feet.
Their performance has been spectacular. We used them during both weekends of
the CQWW contest. The front to back is much better than the 402CD and their
VSWR performance is less than 1.3:1 from 7 to 7.3 MHz.
The modifications are not hard, but do take some effort. I am feeding them
with W0IYH chokes.
You can see a picture of them on the tower on the front page of my web site,
upper right side.
73!
Tim K3LR
http://www.k3lr.com
K3LR DX Cluster - Telnet to dx.k3lr.com
-----Original Message-----
From: towertalk-bounces@contesting.com
[mailto:towertalk-bounces@contesting.com] On Behalf Of Bob Selbrede, K6ZZ
Sent: Friday, December 07, 2007 8:26 AM
To: towertalk@contesting.com
Subject: [TowerTalk] XM-240 to Moxon 240
I'm suprised there hasn't been much chatter on TT from folks
converting their stock 402-CD or XM-240 over to the Moxon
design published by W6NL. I wonder how many of them have
been built and are in the air being used today? The mod
concept has been around for several years and it seems
straightforward. The benefits of the conversion appear to
be significant (improved Gain, F/B, 7.0-7.3 SWR under 1.5:1,
no coils, no interaction with stacked tribanders, etc).
Seems like a great mod to do.
I have a new XM-240 assembled and ready to install and I'm
giving thought to modifying it before installing it. Has
anyone had bad experiences with this mod?
Bob K6ZZ
----- Original Message Follows -----
From: "Bill Parry" <bparry@rgv.rr.com>
To: <towertalk@contesting.com>
Subject: Re: [TowerTalk] Cushcraft 40-2CD skywalker
Date: Fri, 7 Dec 2007 07:34:53 -0600
> FYI. I just replaced all four coils on the elements on my
> XM240 (lightning) and the replacement cost for the new
> coils from Cushcraft is $50 apiece. The replacement parts
> seem to be readily available.
>
> Bill, W5VX
>
> -----Original Message-----
> From: towertalk-bounces@contesting.com
> [mailto:towertalk-bounces@contesting.com] On Behalf Of
> Dick Green WC1M Sent: Thursday, December 06, 2007 1:46 PM
> To: 'Roger Cooke'; towertalk@contesting.com
> Subject: Re: [TowerTalk] Cushcraft 40-2CD skywalker
>
> Roger,
>
> The primary mod is to strengthen the boom and elements.
>
> Try this link: http://www.qsl.net/k7vc/402cd.html. It's an
> article by Dave Leeson, W6QHS, on strengthening the
> 40-2CD. It's pretty extensive. I believe there's another
> article detailing a subset of Dave's modifications that
> appeared in the ARRL's National Contest Journal, but
> offhand I don't know the date or author. My 40-2CD, which
> I also purchased second-hand, was quite old (#5 or #6 off
> the production line) and the elements had drooped
> significantly. I replaced the tubing in and near the
> center of each element, and reinforced it per the article
> in NCJ.
>
> You should check the coils and their screws to make sure
> they're in good condition. Replacements can be ordered
> from Cushcraft or you can fabricate your own.
>
> 73, Dick WC1M
>
> > -----Original Message-----
> > From: Roger Cooke [mailto:g3ldi@yahoo.co.uk]
> > Sent: Thursday, December 06, 2007 9:54 AM
> > To: towertalk@contesting.com
> > Subject: [TowerTalk] Cushcraft 40-2CD skywalker
> >
> > Hi.
> >
> > I have just obtained a second hand one of these and I
> > think I have missed
> > out on some mails regarding this antenna. Are there any
> > mods to do before
> > putting it up? I am not sure what condition it is in as
> > it has been stored for
> > a number of years, but it should not have suffered too
> > much.
> > Any comments or suggestions appreciated. I am thinking
> > of using a Pro-Sis-Tel P-61 rotor as it is not too
> > heavy.
> >
> > 73 de Roger, G3LDI
> >
> >
> > Regards from Roger, G3LDI
> > Swardeston, Norfolk.
> >
> >
> > ---------------------------------
> > Sent from Yahoo! - the World's favourite mail.
>
> _______________________________________________
>
>
>
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>
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