Somewhere in the NCJ archives you can search for my prototype "2 element W6RTT
40M Droopy"....no loading coils...about 5 bucks in cost. It worked great on
top of a 54' Tristao crank-up tower. It was built with wire and yard sticks
(not for windy areas, but can be beefed up with better selection of supports).
The yardsticks were used as spacers at each end of a 24' Hy-Gain 204BA boom.
Bamboo sticks were stuffed at the reflector tips and front director tips. 1/2
wave #16 insulated wire was strung using this spreader arrangement in a driven
element/director setup. The left over wire drooping down the element tips was
kept from getting tangled by adding a fishing tackle lead weight. It had great
forward gain (approx 5.5 db). SWR was just like you would expect a full size 2
element beam to be. I used it in one SS contest, then took it down. It even
worked on 15M
How's that for a tribander? Great fun. Been thinking about doing it again....
----- Original Message -----
From: <K3BU@aol.com>
To: <Towertalk@contesting.com>
Sent: Tuesday, April 20, 2004 7:05 PM
Subject: Re: [TowerTalk] Short Dipole for 40M
> In a message dated 4/20/04 8:08:45 PM Eastern Daylight Time, k3bz@arrl.net
> writes:
> >>If anyone has time to look, there's a design at
> http://www.flashwebhost.com/circuit/shortant.php
> I'd appreciate opinions and comments.<<
>
> The worst case of shortening the efficiency of antenna by center loading it.
>
> The best is Moxon Rectangle, next best hats at the ends of elements, next
> best loading coils about 2/3 out from the center of elements, next loading
> stubs.
>
> See argument about current in loading coils at www.K3BU.us under articles.
> You should try to get max current carrying portion of the radiator as long as
> possible and not to "shrink" it by coils.
> Moxon besides shortening the antenna, by critical coupling via bent elements
> provides best pattern and F/B for 2 el. antenna.
>
> Yuri, K3BU.us
> _______________________________________________
>
> See: http://www.mscomputer.com for "Self Supporting Towers", "Wireless
> Weather Stations", and lot's more. Call Toll Free, 1-800-333-9041 with any
> questions and ask for Sherman, W2FLA.
>
> _______________________________________________
> TowerTalk mailing list
> TowerTalk@contesting.com
> http://lists.contesting.com/mailman/listinfo/towertalk
>
_______________________________________________
See: http://www.mscomputer.com for "Self Supporting Towers", "Wireless Weather
Stations", and lot's more. Call Toll Free, 1-800-333-9041 with any questions
and ask for Sherman, W2FLA.
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