Hello to all; I don't know anything about the XM-240
but I can give my experience w/ the 40-2CD. I have
one mounted at 137' on top of a Rohn 45G tower. I
made the Dave Leeson mods, using aluminum tubing
that I bought from Texas Towers.
I did not use any sheet metal screws in the construction.
Where I needed fasteners to hold the inner pieces in
place, I used 10-32 hex head stainless steel screws w/
internal lockwashers under the heads (I drilled & tapped
the material to accommodate these fasteners). I did not
bother with the traps; they appeared to be in good con-
dition, so I figured that I'd "leave well enough alone."
I got rid of the boom "struts" and employ 3/32" galvan-
ized aircraft cable as overhead boom supports (like my
TH7 uses). I think that's about it, as far as the physical
construction details are concerned.
My 40-2CD receives a heck of a lot of wind at 137' &
seems to be holding up just fine. I used the "CW setting"
for element lengths, etc., as I operate abt 99-1/2% CW.
For what I consider to be a "small, light-weight antenna,"
the 40-2CD is a VERY GOOD performer. With the
settings that I used, the antenna is usable only in the CW
portion of the band. I don't know anything about adjust-
ing it to some "mid-setting."
To give an idea of how well the antenna performs (on CW),
in the most recent CQWW CW contest I was in, I oper-
ated w/ only 100 watts and worked EVERYTHING that
I was able to hear; usually on the 1st or 2nd call. On some
of the larger pile-ups, I made a notation of them & came
back to them later, when the pile-ups died down some-
what and was then able to work the stns vy easily.
I put this antenna up, as a "temporary" antenna; eventually,
it will be replaced with a home-built copy of a Telrex
40M346, which was Telrex's 40 meter yagi w/ 3 full-
size elements (nearly full size) on a 46' long boom. I'm
guessing that when the 40M346 copy is all done, it will
weigh somewhere around 215 pounds - considerably
heavier & larger than the 40-2CD that is now up! But
the Telrex copy will be broad-banded enough to usable
over the entire 40 meter band. Anyway, that's my plans!
73 de Brad @ Radio Free Roscoe (IL)
----- Original Message -----
From: "M K Miller" <qcs0041@lexcominc.net>
To: <towertalk@contesting.com>
Sent: Tuesday, April 17, 2001 3:14 PM
Subject: [TowerTalk] Opinions please--re: 40-2CD compared to XM-240
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