F/B,Gain and SWR are easily measurable. Obviously, since F/B and Gain don't
both occur with the same element lengths and spacing, there is always a
compromise, however there is an even bigger compromise when trying to use
the same element spacing over multiple bands. The most noticeable effect
will be reduced F/B as the reflector is electrically further away from the
driven element as you go higher in frequency. Gain is less effected and
apparently the 22 ohm impedance is maintained by the element length
settings. The SteppIR is an excellent multiband antenna, however I am sure
a properly designed monobander with the same boom length that would have
better F/B and Gain on at least some of the bands that this antenna covers.
----- Original Message -----
From: "Jim Lux" <jimlux@earthlink.net>
To: <john@kk9a.com>; <TOWERTALK@contesting.com>
Cc: <dezrat@copper.net>
Sent: Sunday, May 13, 2007 1:49 PM
Subject: Re: [TowerTalk] C31XR versus SteppIR
At 10:38 AM 5/13/2007, john@kk9a.com wrote:
>Joe responded (actually shouted) this statement after I stated the
>following
>last Friday night when comparing the subject antennas: "The SteppIR, has
>no
>element interaction problems because the element lengths are adjustable,
>however the spacing is not adjustable and not optimum", Since no limits
>were defined, I understood his comment to mean that within the frequency
>range of the SteppIR, the element spacing is irreverent. If this is
>incorrect, then Joe, W4TV, is actually agreeing with me, that the element
>spacing of the SteppIR is not optimum on all bands.
>
>John KK9A
What's optimum?
Is the deviation from whatever definition of "optimum" is chosen
actually a significant (or even measureable) difference?
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