Bill,
As the original post said, the measurements were in wavelengths. So
you have to first convert your boom length to wavelengths. Take the
square root of that and then convert back to feet.
It is problematic with triband beams. It also indicates the problem
in obtaining a decent spacing for 3 bands. In reality, it will be a
compromise. There are many articles on stacking of tribanders. At
least one is in the ARRL antenna handbook.
73 de Brian/K3KO
Bill Coleman wrote:
>
> On 7/28/01 9:15 AM, alsopb at alsopb@gloryroad.net wrote:
>
> >I queries WX0B about the rule of thumb regarding "optimum" stacking
> >height.
> >
> >Here was his response:
> >***********************************
> >For HF antennas over ground, W2PV did the math correctly and the
> >formula is SQ rt of boom length is the widest stacking distance you
> >should use on a yagi. The results are in boom lengths just as you
> >state.
>
> I'm sorry, I hate to quibble with the experts, but this doesn't seem
> reasonable.
>
> If I stack two A3S antennas, with a 14 foot boom, that's 3.7 feet? That
> seems unreasonably close.
>
> Or did he mean 3.7*14 feet, which would be 52 feet?
>
> So,
>
> widest = boom length * ( boom length ^ 0.5 )
>
> ?
>
> Bill Coleman, AA4LR, PP-ASEL Mail: aa4lr@arrl.net
> Quote: "Not within a thousand years will man ever fly!"
> -- Wilbur Wright, 1901
>
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