[TowerTalk] OWA Inventor?

[Jim Lux]

http://www.naic.edu/~angel/kp4ao/ham/owa.html

describes the underlying concept from W3FET -> use a fat element as the 
driven element: fatter elements have increased bandwidth, but have 
higher feedpoint impedance.  But in a Yagi, the feedpoint impedance is 
low (because of the coupling to the other elements, mostly.. it's sort 
of a "parallel resistor" thing)

So, if you used a fat driven element, you get the combination of wider 
bandwidth AND a feedpoint impedance that is closer to 50 ohms.

It's well known that putting another element close (<0.1 lambda) to a 
dipole is electrically very similar to a fat element, and there you have it.




On 12/12/13 10:19 PM, Jim Thomson wrote:
> Date: Thu, 12 Dec 2013 15:33:08 -0600
> From: Kelly Taylor <ve4xt at mymts.net>
> To: Steve Sacco NN4X <nn4x at embarqmail.com>, <towertalk at contesting.com>
> Subject: Re: [TowerTalk] OWA Inventor?
>
>
> ##  The OWA  doesn’t use TWO driven elements.  That was a KLM concept.
> The OWA only uses ONE driven element... with the 1st director closed spaced.
> I bought YO  4.0 when it 1st came out.....and it would not allow you to space any
> two elements any closer than .09 wavelength.  Thus there was no way to arrive at the
> OWA design.  Ditto  with.... yagimax that came out aprx the same time.
>
> ##  The late VE7WJ, Henry Thel,  once gave a talk about the importance of using close
> spacing between the single DE..and the 1st director.  That was back in the late 70s.
> N6BT came out with OWA, direct 50 ohm fed monobanders for 20-15-10-6m
> I think in the early 90s.   Dunno who cooked up the original design, or which software
> they used, but the concept works superb.  The OWA design has also been used on hb 5-el,
> 20m monoband yagis , with great success.
>
> ##  The F12 OWA, direct 50 ohm fed yagis  are killer ants.
>
> Jim   VE7RF
>
>
>
>
>
> Virtually every reference on Google searches to the Optimized Wideband
> Antenna refers to WA3FET as the inventor. None refers to N6BT. Most also
> co-credit K3LR for the OWA.
>
> You might be able to outfox some Google search results, but not every single
> one.
>
> N6BT's contribution, which I don't mean to disparage, is a system to couple
> multiple driven elements parasitically to eliminate traps in multi-band
> antennas. He referred to them as multi-monoband arrays, since most of the
> F12 antennas use discrete elements for each band of operation rather than
> using traps to multipurpose elements.
>
> The OWA, if I recall correctly, was around before Force12 was even a gleam
> in N6BT's eyes. And, again IIRC, the OWA is a monoband antenna that uses TWO
> driven elements and specific element spacing to provide consistent gain,
> matching and F/B over a greater portion of a particular band than typical.
>
> 73, kelly
> ve4xt
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