You need to be careful here. I had my 40-2CD down
last fall for some minor repairs. I had previously
done the W6NL/W6QHS mods but had not redrilled the
loading coil connections and decided to do this while
the antenna was down. All four loading coil
assemblies looked fine and the original shrink wrap
was in good condition. I was very suprised when I cut
the shrink back on the first coil to discover that the
steel self-tap screw was badly rusted and that
corrosion was evident at the coil-to-tubing
connection. I cleaned everything, drilled and
installed stainless hardware with penetrox as per the
mod. In all, I found three of the four loading coils
to be in the same condition. The last one was in
perfect condition like the day it was made (bright and
shiny)! There was no visable difference in the
hardware used or in the construction in the four
coils. Go figure! Bottom line is that you may not be
able to tell the condition of these connections by
looking at the outside of the assembly.
73, Stew K3ND
SNIP
> I found that the redrilling of the coil connection
> screw is necessary only
> if the factory shrink-wrap is incomplete, as it was
> on one of my
> 40-2CDs. However, on my other one, all I did was
> obtain some large diameter
> 3M shrink-wrap and add that shrink-wrap on top of
> the
> factory shrink-wrap to ensure that the entire
> coil/screw unit was totally
> covered. Then, I heated the shrink-wrap so that it
> shrunk tight to the
> aluminum tubing.
>
> I tune all my antennas to CW and suffer any
> degradation on SSB. (We
> contesters who love CW tend to do that). If you
> tune
> an antenna for SSB, you more than "suffer" on CW,
> the physics doesn't work
> that way! ;-)
>
> Check out the design of a competitive contest
> antenna system:
> www.erols.com/n3rr
>
> Bill, N3RR
>
>
>
> ----- Original Message -----
> From: <n4kg@juno.com>
> To: <TOWERTALK@contesting.com>;
> <qcs0041@lexcominc.net>
> Sent: Wednesday, April 18, 2001 6:16 AM
> Subject: Re: [TowerTalk] Opinions please--re: 40-2CD
> compared to XM-240
>
>
> > You need to read the W6QHS (now W6NL)
> > article in QST on refurbishing the 402CD.
>
> >
> > QHS also recommended removing the self tapping
> screws
> > in the loading coils and replacing them with
> Stainless Steel
> > screws with nuts and lock washers. I did not do
> this but
> > I know several people have reported problems with
> the original
> > screws.
>
> > K7LXC recommends tuning the elements somewhere
> between
> > the CW and MID settings for slightly better
> bandwidth / performance
> > on SSB.
>
>
>
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>
> -----
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