Andrew Williamson wrote:
>
> In message <33000DDF.89F@westky.com>, Bud <k4isv@westky.com> writes
>
> >I submit the following as "general rules" I have observed in working
> >with stacked yagis. To be sure, there are exceptions and no one antenna
> >is BEST. The following assume properly installed, tuned, phased, spaced
> >etc... :
>
> >6) swr of a properly phased stack is lowest when in the same direction
> >and highest when 180 deg. apart
>
> Hi guys (and gals),
>
> A quick query on Bud's point number 6. Just how much does the SWR vary
> when rotating the top antenna relative to the bottom one. Hopefully in
> the next 12 months we will be stacking yagis at GI0KOW (top one
> rotatable only) and was wondering about this. The phasing will probably
> be done with Dunestar boxes. My ETO 91B isn't to keen on any SWR over
> about 1.5:1, so would the SWR fluctuation when rotating be a problem?
>
> Not sure if the number of elements would make any difference, but we
> will be stacking 6's on 10 and 15M, and 4's on 20M.
I had a top rotary 10 meter beam at 85' and a NW lower fixed at 45' and a
NE fixed at 40' I did not even notice the SWR variance when I rotated
the top beam. This arrangement worked VERY well. I am looking forward
to many stacks at my new QTH.
Chuck, KE5FI
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