On Tue, Mar 23, 2010 at 10:12 AM, Jeff Wilson <jjw5257@yahoo.ca> wrote:
> I think I read somewhere that twisting the ladderline to minimize wind
> loading would impair the radiation efficiency.
> Would this be a problem with the top-loaded vertical (shorted ladderline
> feed) or with the Zepp operation on 80m and down?
450 window line usage at NY4A with the anti-wind twisting seems to be
completely normal. Just note in passing that 450 ohm line usually is
not 450, having measured 440 through 410 (with or without twist).
Will also note that long runs of 450 window line without the twist get
torn up very quickly, for us anyway rendering any impedance issues
moot.
The vertical run of 450 window line used as a 160 vertical radiator
has broken many times from wind twist stress, regardless of the twist.
Howie has recently replaced the 450 window line with a 300 ohm
transmitting grade window line. Less of a drag in the wind. We'll
see.
73, Guy.
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UR RST IS ... ... ..9 QSB QSB - hw? BK
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