Dino, have you gone past comparing the two
owner's manuals and actually tried this yet?
In comparing the 40-2CD and the XM240, CC
uses the same loading coil assembly (LCA) and
also shows very similar distances from boom to
the loading coil(s) ... 160" is what you want for
the W6NL redesign per page 2 of the PDF.
I note the inner spec 40-2CD reflector to be 160" and
the 40-2CD driven element to be 161" <most likely due
to the construction of the 40-2CD center insulator?>.
As the sections being replaced/extended are 7/8"
diameter<in the XM240 AND the 40-2CD> I
don't understand the concern from that point out
if you use the new tubing lengths/sizes in the text for
the extensions and the tee loading elements?
<Yes, there may be slight taper concerns due to
the slight differences in the inner element sections,
exactly how much really? I don't know this piece
yet. As both stock designs, taking the differences in
the end tips into consideration, worked as designed
in a stock 40m setup, this may not be a significant
factor at all> <Calling K4SAV, any input here?>
So, yes, the end tips <past the LCA> are different
lengths as are the tubing sizes ... and as the W6NL
redesign uses modified XM240 tips specs <and NOT
the 40-2CD stock ends> ... I don't see where that
difference matters anymore if you simply use material
based on the W6NL/XM240 spec'd end pieces. QSL?
Dave, W6NL, even has a footnote on page 2 on this
saying they don't have to be the original CC parts ...
Mechanically, the 40-2CD elements/boom needs
some beefing, and that's not news, several articles
over the years have provided the details for that part
via W6NL and N4KG. W9RE used to offer a "kit".
The XM240 reflector is not grounded, but I recall
W6NL stating it could be grounded, so that issue
goes away as the 40-2CD IS grounded stock.
I am not so convinced of the "EVERYTHING"
statement ... please enlighten me! B-) B-) B-)
Exactly what else needs to changed?
Thanks es 73 de Billy, AA4NU
----- Original Message -----
From: "Dino Darling" <dino@k6rix.com>
Sent: Tuesday, March 18, 2008 12:15 AM
Subject: Re: [TowerTalk] Full Size Moxon is Up
>Not without some upgrades to the 40-2CD. As pointed out on this
>reflector a couple of months back, AA6PW and I sat down with BOTH
>manuals side by side, and the XM model is a bit more robust than the
>original CD. The tubing diameter is smaller which would require
>re-stepping the elements and beefing up...EVERYTHING.
>
>But to answer your question; YES, it can be done.
>
>Dino
>
>At 06:50 PM 3/17/2008, Dick Green WC1M wrote:
>
>>Can this mod be done to a 40-2CD?
>>
>>73, Dick WC1M
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