I extracted this topic from the other thread on the Model 238.
How does bad weather affect openwire compared to its effect on window line?
Lots of opinions, lots of myths.
Bob Allison (WB1CGM) and Joel Hallas (W1ZR) tested this to find out.
Their results are reported in the November 2009 issue of QST on page 66.
See: http://www.dj0ip.de/spiderbeam-1/spiderpole/pole-base-mount/ and then
select "W1ZR" as author and "2009" as year.
Unfortunately you have to be a member of ARRL to download this and it is
copyrighted, otherwise I would post the download on my web.
Summary, for 95 ft. of feedline (the length they tested), the change is
negligible in both.
It is ever so slightly worse with window line, but less than 0.2dB.
NEGLIGIBLE!
The real difference is, true openwire changes it impedance only slightly
when wet, whereas the window line changes more and generally requires
re-tuning the matchbox.
One word of caution, which should be obvious: Neither are suitable for
running along the ground, whether wet or dry!
Being an operwire fanatic, I personally found this to be one of the most
useful articles ever published in QST.
73
Rick, DJ0IP
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