Use of lattice line to feed dipole
On Sat, 23 Sep 2006 15:23:07 -0400, Mike Coslo
wrote:
John, N9JG wrote:
The author used a wetting agent.
"Cecil Moore" wrote in message
m...
John, N9JG wrote:
An excellent article. It appears to indicate that at 7 MHz a feed line
made from 100' of Wireman 554 window line would have a loss of about 2 db
when the line is wet. When the line is dry, the loss is insignificant.
I've often wondered how someone "wets" a vertical feedline
without using soap.
So is the lesson that Ladder line sucks, or is it that we shouldn't
wash our ladder line with soap and water? 8^)
Some suggest coating the ladder line with various forms of waxes, eg
silicon car polish for various reasons, including minimising the
change to the line characteristics with precipitation.
I don't know if there is reliable evidence as to the efficacy of these
measures, and what compounds are to be preferred. I see it discussed
on eham, but that doesn't necessarily mean it is bunk!
I don't know that it is fair to say that "Ladder line sucks", but it
is well known that it is adversely affected by moisture. Ladder line
is not so good wet or dry as to disregard its losses in all situations
(ie in general).
Like everything, it has its limitations, and with knowledge we can use
it effectively within those limitations.
Owen
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