> >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
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