Ok, let me try the simple Executive summary:
Taking a length of window-line fresh off the drum, and dowsing it with
UK (midlands) rain water I see an small increase in attenuation at the
top of the HF band that would not be discernible unless you had a 250ft
run or longer. At the same time there is a shift in Velocity Factor that
*would* be noticeable in a doublet/window-line application because of
the impedance transformation it introduces. Those results seem to be
entirely consistent with the ARRL results.
If I introduce a wetting agent like Wes Stewart did, I see a large
increase in loss which is of the same order as he observed. It's unclear
to me whether that's because it produces much more complete "wetting",
or whether it's due to something in the agent itself. If the latter,
it's obviously a very artificial condition.
Interestingly the ARRL experiment also included window-line that had
been outside for some time; it performed about the same as the new stuff!
Like most experiments you can always find more to do: what about waxing
the line; what's the effect of snow & ice as opposed to rain; etc etc.
For now, I'm content that the discrepancy between Stewart's results and
the ARRL results can be explained .... at least to my satisfaction :)
I may well leave the experimental line in place and try it again if we
get some more sever whether conditions in the winter.
Steve G3TXQ
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