I originally had the EF 240 at 80 ft. It performed pretty darned well with
a 230 - 250khz bandwidth as advertised. Its very lightweight but its
fragile. I beefed up some of its weak points that needed service after 3 or
4 years. For the money, it was the best bang for the buck and I did well
with it. I took it down after about 5 years and put it into due south
service at 50 ft. Its now on the ground because that tower was taken down.
Now that I am higher power, I use a 2 el Delta loop in the trees and that
works adequately.
I now have a M2 3 el 40M3L. Its definitely physically better built although
it has one linear loading flaw mechanically that I have since upgraded on
all elements. It has much better front to back than the 2 el Force 12 and
"holds a frequency better". I am happy with the upgrade.
To me the ONLY reason to got to the 48ft dual driven element 40M beams is
the bandwidth. I don't think the extra dB or so is materially better than
the 40M3L but the BW is only 200khz and it rolls off SHARPLY at the edges.
I have it pushed down towards CW, so I see it start rolling off around 7180.
Given the concentration of SSB from 7200 and down, I am okay with the
compromise. I can reduce power and answer anyone right up to 7290 if
needed. I am sure its barely a rotary dipole up there.
If it was me, in Brazil, already owning a 402CD, I would be tempted to buy a
longer boom and adding a 3rd element and re-optimizing for a 3el. A brand
new 3 el shipped from the states is going to be a BIG expense and won't be
much better than a modified 402CD for an extra element.
Ed N1UR
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