The 40-2CD presents a reasonable match on 17M (<2:1 SWR)
and seems to work as an effective rotary dipole on that band.
The SWR on 12M is higher but can be tuned with most antenna
tuners. I know many people who use this as their primary 17M
antenna and a few who also use it on 12M. It should be possible
to add a close spaced 12M parasleeve driven element if you want
to achieve low 12M SWR without a tuner.
It would be a simple matter to add 12 and 17 meter reflectors
(or a trapped reflector a la A3WS) to achieve 2 effective elements
on each band. The fact that there are no elements in front of the
driven element means that there will be NO destructive interference
as experienced with 3 or more elements on lower bands. These
additional elements for the WARC bands will NOT affect 40M
operation.
I have often thought such an option would make an interesting
product enhancement for Cushcraft.
73 / GL, Tom N4KG
.....................................
On Tue, 30 Jun 1998 19:08:47 -0400 "DavidC" <davidc@bit-net.com> writes:
>
>Over the past week several folks have told me that the 40-2CD tunes up
>nicely and runs real well on 12 and 17, and that according to an
>MFJ-259
>shows a good swr and impedance on 6m (multiple wavelengths I guess!).
>
>I would greatly value reports of actual experiences with this antenna
>on
>these non-design frequencies as I move closer to finalizing my antenna
>plans.
>
>These are all secondary bands for me and if this beam will handle them
>I
>will be able to settle on it as adequate for those bands and return my
>focus to maximizing 10-15-20.
>
>This is a wonderful reflector, made so by all herein who love the
>hobby and
>enjoy the sharing of knowledge and experience! Thanks & 73, DavidC
>AA1FA
>
>
>--
>FAQ on WWW: http://www.contesting.com/towertalkfaq.html
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>Administrative requests: towertalk-REQUEST@contesting.com
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>
>
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