[TowerTalk] Optimum Stacking Distance

[Maurizio Panicara]

If my memory doesn't fail, the stacking distance by boomlenght was something
grown many years ago in the VHF/UHF to roughly approach a maximal stacking
gain with the smallest spacing in case of very long boom yagis.
The maximal yagi gain with several WL booms was assumed as strictly related,
or converging nearly as a linear function, to the antenna boomlenght.
The next assumption was that gain determines the "capture area" of an
antenna and if the two "areas" doesn't overlap, then the aimed 3 dB gain is
already achieved.
Sometimes a certain amount of distance reduction from max gain was accepted
as a little price to pay in order to obtain a cleaner pattern.
All the above was rough and isn't any more acceptable but anyway has little
to do with HF stacking where ground shape and heights from ground play a
consistent role setting the free space gain meaningless.
A wider coverage of vertical angles and a clean pattern are generally the
goals to be achieved on short waves antennas stacking.
The best solution for each individual location and preferences (and array)
is almost peculiar and unique.

73,
Mauri I4JMY



----- Original Message -----
From: "Tom Rauch" <w8ji@akorn.net>
To: "Robert Shohet" <kq2m@mags.net>; <towertalk@contesting.com>; "Bill
Hider" <n3rr@erols.com>
Sent: Friday, July 27, 2001 11:16 PM
Subject: RE: [TowerTalk] Optimum Stacking Distance



>
> So you see, stacking distance has absolutely nothing to do with
> boom length! Optimum stacking distance is a function of how
> narrow the original pattern is....or where the minor lobes are that
> you want to get rid of.
>

> Rules of thumb do not work.
>

> Stacking distance relates only to how wide the individual antenna
> patterns are (over earth), and if you want high gain or good side
> lobe suppression (you can't normally get both). The narrower each
> antennas pattern, the wider stacking distance becomes. It has
> nothing at all to do with boom length.
> 73, Tom W8JI
> W8JI@contesting.com
>




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