I don't want to get in the middle of this, but I just ran EZNEC models
comparing the 4-el SteppIR and Force-12 EF-420 on 20m at 96'. The SteppIR
boom is 32'; the EF-420 boom is 30' (and presumably optimized.) Results:
4-el SteppIR Force-12 EF420
Elevation at max gain: 10 degrees 10 degrees
Forward gain: 14.36 dBi 14.29 dBi
Front/Back: 18.12 dBi 17.35 dBi
Front/Side: 18.12 dBi 17.35 dBi
Beamwidth: 60 degrees 60 degrees
It would be hard to tell the difference between these two antennas. I have
both installed, but the EF-420 is only at 72' on a tower that doesn't have
as good terrain as the tower on which the SteppIR is mounted. The SteppIR
consistently outperforms the EF-420, usually by as much as 5 dB. I attribute
that entirely to the difference in height and terrain.
I have not done models for 15m and 10m because I don't have data for any
4-el antennas for those bands. But I have compared the 4-el SteppIR with a
Force-12 515 (5-el on 15m, 24' boom) and a Force-12 616 (6-el on 10m, 24'
boom.) The gain figures are nearly identical, but the F/B on the SteppIRs is
lower, especially on 10m (a well-known characteristic of the SteppIR design,
resulting from inability to place the elements optimally on all three
bands.) The gain being comparable suggests that optimized 4-el monobanders
for 15m and 10m would outperform the SteppIR. But I don't know by how much.
73, Dick WC1M
> -----Original Message-----
> From: Bob Maser [mailto:bmaser@tampabay.rr.com]
> Sent: Friday, June 29, 2007 12:00 PM
> To: Joe Subich, W4TV; 'Carl Smidt'; towertalk@contesting.com;
> SteppIR@yahoogroups.com
> Subject: Re: [TowerTalk] SteppIR
>
> Joe, have you been smoking weed again? It's affecting your brain.
> Your
> logic makes no sense at all. A 4 element on a 34 foot boom at the same
> height and optimized with YO or some other optimization program will
> outperform the SteppIR if both antennas are reasonably close by. You
> sound
> like someone trying to justify spending all that money. Better you
> should
> light some candles and pray that the element drive motors stand up.
>
> Bob W6TR
> ----- Original Message -----
> From: "Joe Subich, W4TV" <w4tv@subich.com>
> To: "'Bob Maser'" <bmaser@tampabay.rr.com>; "'Carl Smidt'"
> <xveoneov@primus.ca>; <towertalk@contesting.com>;
> <SteppIR@yahoogroups.com>
> Sent: Friday, June 29, 2007 10:30 AM
> Subject: RE: [TowerTalk] SteppIR
>
>
> >
> > Bob,
> >
> >> For any specific band most monoband antennas will stomp a SteppIR,
> >> assuming that the boom length is the same or longer than the
> SteppIR.
> >
> > That's complete nonsense unless you are comparing something like a
> > 60 foot boom monobander. YO shows a 1 dB advantage for the 4 element
> > over the 205CA because the 205CA gives up gain to maintain usable SWR
> > across the entire band. The N6BV optimized design (BV205) is about
> .5 dB
> > below the SteppIR.
> >
> > It takes a much larger monobander (6 el 60 foot on 20, 6 el 48 foot
> > on 15 and 7 el 48 foot on 10) to achieve at least 1 dB more gain than
> > the SteppIR. Sure, one could put up a set of WA3FET (K3LR) OWA
> antennas
> > for each band but not on one tower.
> >
> > 73,
> >
> > ... Joe, W4TV
> >
> >
> >
> >
> >
> >> -----Original Message-----
> >> From: towertalk-bounces@contesting.com
> >> [mailto:towertalk-bounces@contesting.com] On Behalf Of Bob Maser
> >> Sent: Friday, June 29, 2007 8:50 AM
> >> To: Carl Smidt; Richard J. Fiero II W5TFW;
> >> towertalk@contesting.com; SteppIR@yahoogroups.com
> >> Subject: Re: [TowerTalk] SteppIR
> >>
> >>
> >> Carl, your bragging doesn't make any sense at all. For any
> >> specific band
> >> most monoband antennas will stomp a SteppIR, assuming that
> >> the boom length
> >> is the same or longer than the SteppIR. For band hopping
> >> convenience, I
> >> would agree with you that the SteppIR antenna is better than most
> >> tribanders. All of this bickering back and forth has become
> >> tedious at
> >> best.
> >>
> >> Bob W6TR
>
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