Tom, I started with the taper schedule in Jims original paper and it was
augmented by another that appeared in one of the contest journals, probably
YCCC.
Later on and after it was up for several years I confirmed with YO; right on
the money. That may have actually been the schedule built in to YO.
Im not familiar with this OWA but Ive built several 6M and up yagis using
the close coupled directors as described in the ARRL Antenna Book designs by
K1FO and elsewhere for about 20 years. Nothing secret about it. YO handled
it very well when I took a 6 el Cushcraft 6M Boomer and added 2 more
elements. Superb pattern (I need it due to local noise sources) and
bandwidth. Duplicated the performance with many other commercial 6M yagis
that I modified.
YO tells you how close to theroetical maximum gain, based on boom length,
your design comes. It also gives a graphical display of current distribution
on the fly which is very beneficial when moving elements around.
Carl
KM1H
Carl
KM1H
----- Original Message -----
From: "Tom Rauch" <w8ji@contesting.com>
To: "jeremy-ca" <km1h@jeremy.mv.com>; <towertalk@contesting.com>
Sent: Friday, June 01, 2007 10:45 PM
Subject: Re: [TowerTalk] Yagiis
>
>> Sounds like a Hi Gain, they always liked to add extra
>> elements.
>> I built PV 4el on 10/15/20 in 1983. They performed right
>> by the published curves and I used a (compensated) severe
>> taper on 20M. BTW, its a 40' boom on 20M.
>
> What I plan on doing Carl is actually adjusting the antenna
> for maximum gain with real measurements. A real antenna in
> the real world.
> Then I will copy it.
>
> My models seem to have problems with element taper, so I
> have no other option.
>
> 73 Tom
>
>
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