> There is an optional fixed 6 meter director available for the SteppIR
> that is suppose to greatly improves the F/B ratio:
>
> http://www.steppir.com/
>
> Look under the "products" tab for the "6 meter passive element kit".
> The list price is $79.95, but you could probably make your own easily
> enough (it looks like nothing more than a piece of tubing and a U-bolt).
> Of course assuming this is a director, you probably lose the ability to
> do instant 180 deg switching on 6 meters with this installed.
>
> 73 de Mike, W4EF....
>
Roger that, Mike. But modeling indicates less than 15 dB F/B as
best achievable on 10m, and about 12 dB on 12m; don't think the extra 6m
element will help those, although possibly it does. Anybody have any real
data? -WB2WIK/6
> .................................................
>
> ----- Original Message -----
> From: "Steve Katz" <stevek@jmr.com>
> To: "'Mark Beckwith'" <mark@concertart.com>; <towertalk@contesting.com>
> Sent: Friday, September 13, 2002 3:39 PM
> Subject: RE: [Towertalk] Need Antenna Advice!
>
>
> >
> >
> >
> > > >The StepIR is an optimized 3L beam AT
> > > >ALL FREQUENCIES.
> > >
> > > That depends on how you define the word "optimized," eh? I don't call
> > > fixed
> > > element locations on the boom optimized on more than one band.
> > >
> > > Mark, N5OT
> > >
> > [Steve Katz] Mark, I have to agree. Unless this antenna defies all
> > the modeling programs, using a 16' boom and fixed element locations
> provided
> > in the SteppIR manual, and modeling using NEC, if I adjust the element
> > lengths in 1" increments indefinitely, to try every combination of
> element
> > lengths there is from 10" to 432" per element using (N+1...) algorithms,
> I
> > cannot come up with any combination that provides more than about 6dB
> F/B
> on
> > six meters, for example. The original claims for F/B on "all bands" is
> > "20-50 dB, depending on frequency" for the 3L model, but I can't use any
> > modeling integers that indicate that, at any element lengths or any
> height
> > above ground. If the inventor/manufacturer can provide us with some new
> > data on this matter, I'd love to receive it! Better still, I'd like to
> > know what the exact element lengths are to provide max F/B on each band,
> > based on the 16' boom length and fixed element spacing. Then I can
> scale
> it
> > 1:10 and stick the model in our RF anechoic chamber here at the lab, and
> > take actual (empirical) data. I'll be happy to provide the test report
> in
> > this forum, if I can get the data to make the model. -WB2WIK/6
> >
> >
> > > _______________________________________________
> > > Self Supporting Towers, Wireless Weather Stations, see web site:
> > > http://www.mscomputer.com
> > > Call 888-333-9041 to place your order, mention you saw this ad and
> take
> an
> > > additional 5 percent off
> > > any weather station price.
> > > _______________________________________________
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> > > Towertalk@contesting.com
> > > http://lists.contesting.com/mailman/listinfo/towertalk
> > _______________________________________________
> > Self Supporting Towers, Wireless Weather Stations, see web site:
> http://www.mscomputer.com
> > Call 888-333-9041 to place your order, mention you saw this ad and take
> an
> additional 5 percent off
> > any weather station price.
> > _______________________________________________
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> > Towertalk@contesting.com
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> >
>
>
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