At 01:01 PM 7/29/2006, john@kk9a.com wrote:
>The original question (
>http://lists.contesting.com/archives//html/Towertalk/2006-07/msg00834.html )
>inquired if the angle of radiation could be changed by adjusting the element
>lengths of 3 element SteppIR. Turning the antenna (even with an azimuth
>rotator) won't change the angle of radiation.
yes, but changing the relative lengths of the elements (which is what the
SteppIR is all about) *can* change the vertical pattern: by changing the
relative phases of the element currents to change from a end-fire to
something with two lobes above and below horizontal.
>John KK9A
>
>
>From: "Tom Osborne" Date: Sat, 29 Jul 2006 10:20:37 -0700
>
>I guess I don't understand why someone would want to do all this to shift
>the pattern of the antenna in a different direction. Why not just rotate it
>in the direction you want the pattern to go? I don't think there is any way
>to make it have more gain. 73
>Tom W7WHY
>
>Jim, W6RMK wrote:
> >I like the "squishy water balloon of constant volume" analogy for
> > antenna patterns. You can poke and prod it into a bizarre shape, >but the
> > overall power remains the same.
> >
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