An additional note: I just found out that the loading coils on this
antenna are not wound on solid rods like I had thought, they are wound
on tubes. So a leak anywhere in the element can send water throughout
the whole element. But that makes it even more important that the
antenna be sealed against water or provide a way to drain it. Water
accumulation inside the loading coil can make the performance go to crap
in a hurry. Probably the reason I was having trouble with the initial
SWR check.
So any suggestions are appreciated. Also would like some opinions on
using Noalox on joints. While this antenna is still on the ground, any
other suggestions for correcting common problems would also be
appreciated, such as the end segment problem, W4ZW contributed, thanks Jon.
Jerry, K4SAV
K4SAV wrote:
>For the past eight weeks, my XM240 has been sitting in my back yard on
>concrete blocks, awaiting the arrival of my 4 element SteppIR. Today I
>removed a couple of the elements and found a lot of water inside. (Much
>more than can be accounted for by condensation.) Then I noticed that
>there are no weep holes on this antenna anywhere, and the element ends
>have rubber caps. I inspected the elements for a possible hole to let
>water enter. I found that the loading-hat-cross was mounted by two holes
>drilled through the elements. That looked like the best spot for water
>to enter. I packed duct seal around the screws.
>
>There was also water in the element sections, closer to the boom. This
>section was blocked from the end section by the solid fiberglass rod
>that the loading coil was on. I don’t know how water got in this
>section. Maybe it’s coming in around where the sections are telescoped
>together and clamped with hose clamps, although the fit looks tight and
>there are no obvious holes.
>
>I am beginning to wish I had used Noalox on the areas where elements are
>telescoped together and clamped. The manufacturer didn’t say to do this,
>but it sounds like a good idea to me. Can any of you think of any reason
>why this is not a good idea? What do other antenna manufacturers
>recommend? It’s a lot easier to do this while the antenna is still
>sitting on the ground.
>
>It won’t bet the first time I have violated the prime directive with
>this antenna, I used Noalox on the bolts when the manufacturer said to
>use liquid soap. Soap just seemed too water soluble to me for this
>application.
>
>Jerry, K4SAV
>
>_______________________________________________
>
>See: http://www.mscomputer.com for "Self Supporting Towers", "Wireless
>Weather Stations", and lot's more. Call Toll Free, 1-800-333-9041 with any
>questions and ask for Sherman, W2FLA.
>
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>
>
>
_______________________________________________
See: http://www.mscomputer.com for "Self Supporting Towers", "Wireless Weather
Stations", and lot's more. Call Toll Free, 1-800-333-9041 with any questions
and ask for Sherman, W2FLA.
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