Sylvan:
Reread the footnote again and look at the context in which it is
invoked. It is only for the triangular tower section if they are round
instead of flat plates. Antennas and rotators fall under the catagory of
Tower accessories. then if greater than 2" in diameter the coefficient
is 0.8. If 2" or less then the coefficient is 1.0
Hank / KR7X
Sylvan Katz wrote:
>
> Eugene
>
> Your posting is extremely interesting. I have two questions:
>
> > However, I have since read three of Dick K5IU's various papers
> > (available through ARRL's QEX/Communications Quarterly) in which he cites
>
> (1) Are these available on the web?
>
> > Another point: The nonsense of multiplying the area of a Yagi
> element
> > by 0.67 or 0.6 or anything less than unity (1) to account for its shape is
>
> (2) Why does footnote 8 in the UBC Table 16-H --Pressure Coefficients (C q )
> states "Factors for cylindrical elements are two-thirds of those for flat or
> angular elements"
>
> You note is timely as I am diligently working on a mast design for some
> Force 12 antennas.
>
> .. sylvan
>
> ----------------
> Sylvan Katz
> VE5ZX & G0TZX
> Saskatoon, SK
>
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List Sponsor: Are you thinking about installing a tower this summer? Call us
for information on our fabulous Trylon Titan self-supporting towers - up to
96-feet for less than $2000! at 888-833-3104 <A
HREF="http://www.ChampionRadio.com";>
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