A few comparisons, for your interest, anecdotal stuff:
1. Telrex made a 4-el 20 on 36' boom. W4QAW (who I acquired one from) and
others I've heard talk about this one say it worked well but the front to
back wasn't too good. I think I recall hearing this is true of
half-wavelength-boom antennas. But...poor front to back can be advantageous
in some situations -- e.g. Europe is to the front, from W3, and W5 is to the
back from W3. (hihi). It can be difficult to keep a CQ frequency quiet!
2. Telrex also made a 5-el 20 on a 36' boom. K4FJ, for one (who I acquired
one from) said he never thought it worked very well.
3. Telrex made a 5-el on 46' boom. W0YVA, who I acquired one from, thought
it was the best 20M antenna Telrex made.
4. Telrex made a 6-el on 46' boom that was probably their most common
"larger" 20M antenna. Arguably, it would have worked just as well, or
better, with only 5 elements (and would have been lighter weight and less
windload. Telrex antennas are unnecessarily big and heavy, especially
compared to newer computer-mechanically-designed ones with the rapid taper
lighter weight elements, ala Force 12, Bencher Skyhawk, etc. A bunch of
extra elements that don't "buy you" anything, on a Telrex, add to it
substantially.)
5. Years ago W3LPL, as one "sage" on antennas (particularly around these
parts), standardized on 48' booms for his homebrew antennas not just for 20
but for other bands too, because boom stock comes in 24' lengths, and
because 48', he felt, was "long enough," and was a good mechanical choice
given "the point of diminishing returns" that is out there "somewhere." He
had gone to 56' on 20M one time and decided the extra mechanical challenges
weren't worth it, so he scaled that on back to 48'. He puts 5 elements on
his 48' booms, a design he computer modeled -- which is available on the
K1TTT site, by the way, along with others.
FYI, similarly, on 15M he puts 6 elements on 48', on 10M he puts 7
elements on 48'
and 3 elements on 40M on 48'. I always keep these in mind as my
benchmark for
number of elements per X length of boom is sensible for these bands.
73 - Rich, KE3Q
----- Original Message -----
From: <EL34GUY@aol.com>
To: <towertalk@contesting.com>
Sent: Saturday, October 09, 2004 12:58 PM
Subject: [TowerTalk] Wilson 5 element 20 meter monobander
> Hello,
>
> Does anyone have any experience with the large 3 inch 40ft boom Wison
> monobander for 20 meters? Im wondering how well it works and if it was
> reoptimized
> and what the new spacings might be? 73
>
> Mark
> W0NCL
> _______________________________________________
>
> 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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