Hi Tom:
A very useful post. Let me comment and ask further questions.
> It is very important to place the first insulator as close to the tower
> as possible (3-4 ft) because the tower connects the guys, forming
> a continuous "element" right under your Yagi(s) equal to the distance
> from insulator, through the tower, and back to another insulator.
QSL...I was planning on putting the first insulator 2-3 feet out
from the leg.
> I like to space my insulators 3 - 12 - 12 - 27, or 40, or 58 ft.
Please explain....I got the 3-12-12 part, but after that, you
go 27-40-58?
> If you want to avoid resonances on ALL bands, including the WARC's
> you need to break up your guys every 12 ft or use PHILYSTRAN, at
> least close to the tower, followed by steel guys near the ground to
> prevent damage from fire, abrasion, or cutting.
I don't particularly care about the WARCS...the focus of this effort is
contesting. The chart shows the 40 and 58 foot lengths doing harm
on 12 meters. It seems the 27.5 foot length is *real* close to causing
damage on 20 meters....certainly something to be avoided.
Do you think I will run into trouble using only 58 foot lengths?
Also, phillystran would be fine if the tower were not in the forest.
I have tried to cut down as few trees as possible when placing the tower,
because it was a condition of my variance and my landlord (my wife :-)).
Hence, the abrasion to phillystran is a real concern to me.
73, J.P.
--
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J.P. Kleinhaus, W2XX (fdba AA2DU)
E-mail: w2xx@cloud9.net
As we say in the software business: "You are hosed."
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