I agree with you but I am in the process of optimizing a 205BA, which, as
you know, has a 34 foot boom. I can get better numbers by making it a 4
element than leaving it as a 5 element, and boy, can I get better than the
original 205BA numbers using YO 6.5. BTW, can you tell me what differences
are there between 6.5 and 7.0? I have not been able to find a copy of 7.0
and I can only make my 6.5 work on an old computer that I keep around simply
for running YO.
Bob
----- Original Message -----
From: "Bill Tippett" <btippett@alum.mit.edu>
To: <towertalk@contesting.com>
Sent: Tuesday, March 06, 2007 8:40 PM
Subject: [TowerTalk] Stacking 204BA's
> W6TR:
> >Now, if you did away with the dual driven element
> and make it into a 4 director antenna it would really play.
>
> >I was trying to say was that I found that I
> could get more performance out of my KLM by eliminating
> the dual driven element in favor of a single driven element
>
> Bob we have a different definition of "really
> play". Gain is primarily a function of boom length.
> Changing the feed system has little to do with that. The OWA design
> uses 2 elements for broad-banding even
> though only one is driven whereas KLM uses two actively
> driven elements. The net result is that gain will
> be very similar if both antenna styles are optimized
> in a program like YO using identical input parameters
> (boom length, bandwidth, parameter weightings, etc.)
> Before the days of NEC modeling, I remember Telrex
> advertised their 6 element 20 on a 46 foot boom having
> *significantly* (i.e. dB...not tenths of a dB) more gain
> than a 5 element 20 on the same boom. Now we know that
> is simply not true. The only way to get significantly
> more gain in a properly optimized antenna is by using
> a longer boom.
>
>
> 73, Bill W4ZV
>
>
>
>
>
>
> _______________________________________________
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