Mail*Link(r) SMTP More yagi stacking
You raise some good questions..... I would appreciate you putting out a
compendium of responses. Here's the situation. I have read articles in the
older mags where tests were made....yagis were moved together until they were
inches apart with no ill effect.
Also, what about a "tri-band" yagi....we have multiple yagis VERY CLOSELY
stacked...on the same boom!..... And Wilson (and others) used to make duo
banders which were basically two individual yagis on the same boom. I would
assume that in these situations, if there was any interaction between bands,
this was allowed for when setting final dimensions. After all, the mfgr's
have the ant test ranges..right?
My guess (and only a guess) is that the only way the ant's affect each other
is if the stacking were to put individual elements of the two antennas too
close together so there was a de-tuning affect on an individual element, hence
degrading the ant performance. That of course begs the question as to how
close is too close.....
John's idea of actually measuring the effect would be ideal....although a lot
of work. Surely there is something in print regarding past experiences.
73 es GL, Chuck
WA0ROI
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