Fred,
I did some crude models of the SteppIR 4 Element Yagi. The assumptions are
that these are the TYPICAL compromise settings they program into the
design. You can take that any way you like. All beams are a compromise of
VSWR versus gain versus F/B. Take you choice.
Here are my modeled figures:
20 meters: 9.5 dBi with 18 dB F/B
15Meters: 10.2 dBi with 32 dB F/B
10 meters: 10.31 dBi with 10 dB F/B
Numbers are probably in the ball park. Considering all the variables and
non-optimum boom lengths on some bands, it's not a bad compromise.
73,
Joe, W1JR
At 02:28 PM 5/20/2003 -0700, Fred Roberts wrote:
>Larry-
>
>Most of what I think I know about Yagi design came from spending time
>with the K6STI's Yagi Optimizer design program. Clearly, any design is
>always a tug-of-war between front-to-back, forward gain and SWR. I
>realize the Steppir optimizes SWR vs. frequency, but I wonder what the
>design parameters are for front-to-back and forward gain.
>
>Has anyone thought much about this ... or asked?
>
>73-
>Fred, W6TKV
>
>Larry L Lindblom wrote:
> >
> > They had one in the flea market raised up in the air on a lift. It
> > looked FB, but it wasn't hooked up to a rig which leaves the question of
> > how it performs a ??? For the price it better be a real killer!
> >
> > 73 W0ETC
> > On Sun, 18 May 2003 12:23:02 -0400 Ed Kucharski <k3dne@adelphia.net>
> > writes:
> > > I didn't get to go to Dayton this year...I was wondering if the
> > > FluidMotion
> > > folks had the new 4 element SteppIR antenna on display and if so,
> > > what did
> > > y'all think?
> > > 73,
> > > Ed K3DNE
> > >
> > >
> > > _______________________________________________
> > >
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> >
> > See: http://www.mscomputer.com for "Self Supporting Towers", "Wireless
> Weather Stations", and lot's more. Call Toll Free, 1-800-333-9041 with
> any questions and ask for Sherman, W2FLA.
> >
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>_______________________________________________
>
>See: http://www.mscomputer.com for "Self Supporting Towers", "Wireless
>Weather Stations", and lot's more. Call Toll Free, 1-800-333-9041 with
>any questions and ask for Sherman, W2FLA.
>
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