Mike, NO6X, inquired about 2 element 40 meter beams. The comments that follow
relate to 3 element compact 40 meter beams that basically share the same
concerns as the 2 element versions.
I have a KLM 3 element 40M beam with linear loading. Since I put it up in
1991, it has been up and down the tower at least 5 times for repairs. The
problems that I had were all with the linear loading sections which tend to
develop bad connections both at the connection points to the main elements and
also at the shorting straps.I've incorporated a lot of improvements over the
years, but finally I "gave up" when two of the three Lexon element to boom
insulators broke and elements bent at the largest diameter tubing next to the
insulator. The beam is inoperative now, and very sad to see only the director
and half of the driven element in the air - the rest fell from the tower after
storm damage last winter. I could probably fix this remaining problem by
installing Phyllistran element guys - including small diameter boom extensions
for attaching the outermost guys for the director and the reflector.
Lacking time and patience to bother with the KLM any more, I plan to scrap it,
and would like to replace it with a "factory ready" beam of similar compact
dimensions. I've looked at the M2 and almost bought one. I found out about
problems in the linear loading sections of the M2 40M beams too. In my
correspondence with them, they pointed out some excellent improvements that
they have just recently made. It may be (I hope) that these improvements have
completely solved the problems that M2 had. Time will tell, and if this beam
proves to be mechanically reliable, I will very likely purchase one in the
future.
Regarding the Cushcraft, from all I've read and heard, the improvements in
Dave Leeson's book result in a very reliable antenna. I would like to hear
more about this from others. Unfortunately, Cushcraft has yet to market a
heavy duty "Leesonized" version of this antenna. There is most probably a
large market for such an antenna, and hopefully, they will decide to offer
heavy duty, reliable versions, of their already successful antenna.
I have no experience or comments to offer about the Force 12 antennas.
I've recently found out about a remarkable new concept in compact low
frequency Yagi design by Rod, W7CY. In some correspondence with him, he's
indicated that he can make a 40M version of his publicized 75/80 meter yagis
which he is calling the "CapYagi" (registered trademark). Again, my
hesitation about this antenna, for the moment, is only regarding my desire to
purchase a time proven design - one that will stay up with virtually no
maintenance. I suggest examining the excellent material from Rod at:
http://www.ulio.com/ants.html
73,
Riki, 4X4NJ
Mike wrote:
> OK the decision is getting nearer as what to do for antennas, as my TH7
> stacks wont work. I have decided to go with a big tribander of some sort.
> however Now we come to the 2el. 40 meter beam.
> ANyone have pro's and con's to the following antennas:
>
> Cushcraft
> M2
> Force 12 (EF-240X)
> KLM
>
> OK well that I think sums them up, If you have another please let me know.
> I would prefer to stay away from the CC due to the traps, and the Customer
> service I have recieved in the past, but I will listen to any remarks.
>
> Thanks Mike...NO6X
>
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