I think it depends on what the "extra" element is doing. If it's close to
the DE as in WA3FET's OWA designs (used by K3LR and others), as I heard 'FET
and 'LR note in the Dayton Antenna Forum talk on their 4-el 40, the "first
director" is really a part of the DE, as they described it, more of a
"parasitic driven element..." you end up with kind of a "log cell" feed of 2
elements, though they're not hardwired together as they would be in a
traditional log cell.
I totally accept your argument, and K3LR's note that in this situation a
4-element really should be considered to be a 3-element.
With the older even-element-spacing designs like the Telrex and others, I
think the front to back, bandwidth, or other improvements are a little more
illusive.
73 - Rich, KE3Q
----- Original Message -----
From: "Mel" <mel.martin@axare.mail.net>
To: <towertalk@contesting.com>
Sent: Sunday, October 10, 2004 11:13 AM
Subject: Re: [TowerTalk] Wilson 5 element 20 meter monobander
> >5 elements on 40 ft boom is one element to many for that boom length.
>
> I hear this all the time... Yes 48' is better but with 5 el on 40 you can
> get much better bandwidth performance than with 4 elements on the same
> boom
> length. I think this misconception comes from the idea that you can get as
> much gain on a 40' boom with 4 elements vs 5 elements. But with 5 elements
> you can get better F/B and gain over a much broader freqency range.
> Typically, best configuration is with a close spaced first director like
> the
> OWA antennas.
>
> _______________________________________________
>
> 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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